ECUADOR - Guagua Pichincha volcano

September 14th , 2011

No recent events occured since past year. Last news : As of the 14 th of September 2010, IG reported that no significative change between 6-12 September period. Seismic network continues to record important number of events related to fracture of rock to the interior of the volcano, nevertheless did not register any type of additional anomaly. As of the 17th of April 2010, IG reported that there no change, both the seismic activity and fumarole emission remained at a low level. Previous significative information : as of the 20th of February 2009, IG reported that the seismic stations Geophysical Institute have registered for days back a slight increase of the internal activity of volcano Guagua Pichincha. In previous days 4 phreatic explosions of moderate size have been registered. These explosions happen due to an increase of the internal steam pressure, possibly related to the increase of precipitations observed in the zone of volcano. Therefore the Geophysical Institute recommends that it is not allowed to descend to the interior of the crater since the phreatic explosions could be repeated and the people could take the rock hit, other materials and/or rarefaction waves that are generated by these events. These phreatic explosions they happen generally at times of much rainfall, this is the reason why these explosions not necessarily are indicative of a substantial increase of the activity of volcano Guagua Pichincha. The Geophysical Institute in its preprecautionary eagerness of the security of the people maintains a monitoring permanent of the state of this and other volcanos of the country and will inform opportunely into any change that these can present/display. The activity of the volcano shows a slight increase in its seismic activity with respect to the previous months. 40 volcano-tectonic (VT) earthquakes have been registered, which are related to the fracturing of rocks to the interior of the complex between the 14th and the 18th of February. These earthquakes are of small magnitude, which is the reason why they have not been perceived by the population. It is possible to indicate that during the 2007, an average of 4.2 VT earthquakes per day was had. Also in this time interval 6 events of long period (LP) per day were registered when the average in the 2008 was of 0.3. LP events are related to resonances of cracks full of flowed inside the volcano. In addition it is important to mention the presence of explosions of moderate magnitude, related to the phreatic activity. The 16th of February the guardian of the refuge of the volcano perceived an increase in the scent to sulphur in the high part of the crater. Guagua Pichincha rises immediately W of Quito, Ecuador's capital city. The broad volcanic massif is cut by a large horseshoe-shaped summit caldera, ~6 km in diameter and 600 m deep, that was breached to the W during a slope failure ~50,000 years ago. - Information : I G Quito

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ECUADOR - Tungurahua volcano

January 26th, 2012

IG reported that during 17-22 January low-level seismic activity was detected at Tungurahua and cloud cover mostly prevented observations. On 17 and 20 January steam plumes rose 500 m above the crater. Muddy water in the Achupashal and Pirámide drainages on the NW flanks was noted on 20 January, and a lahar traveled down the Pampas drainage on 21 January. Seismic activity slightly increased during 23-24 January.
IG reported a new episode of activity and increased seismicity from Tungurahua during 11-17 January. On 12 January ashfall was reported in Manzano (8 km SW), Cahuají (8 km SW), and Choglontus (13 km WSW). A lahar descended the Achupashal drainage, carrying blocks up to 1 m in diameter, and caused the road to Baños (9 km N) to be closed. Cloud cover prevented observations of the crater. On 13 January ash-and-gas emissions were observed, and ash plumes rose as high as 7 km (23,000 ft) a.s.l. and drifted W. Ash-fall was reported in Palitahua (6 km SSW) and roaring noises were heard in Cusúa (8 km NW) and Manzano. On 14 January ash emissions rose 500 m above the crater and drifted WSW; ashfall was reported in Choglontus,
Palitahua, and Manzano. Clouds obscured views on 15 January; however ashfall was reported in Palitahua and Manzano. Lahars descended drainages in Juive (NW) and Pondoa (N), carrying blocks 10-20 cm in diameter.
IG reported a decrease in activity from Tungurahua during 4-10 January. On 4 January steam plumes rose as high as 500 m above the crater and drifted W. Additional steam plumes observed on 8 January also drifted W.
IG reported moderate seismic activity at Tungurahua during 28 December-3 January. On 31 December small steam emissions were observed, and on 3 January a gas-and-steam plume rose 200 m above the crater. Ash-fall from last week's explosions accumulated to a depth of 2-4 mm in villages to the SW. IG reported that increased seismicity from Tungurahua was detected during 21-27 December. On 22 December ash plumes rose 500 m above the crater and drifted 2 km W. Ashfall was reported in Baños, Vazcún, and Manzano. One explosion at 0850 generated two small pyroclastic flows that descended the Achupashal and Hacienda drainages. Gas-and-ash plumes rose 4 km a.s.l. and drifted NE. On 23 December ash and gas emissions continued and at night Strombolian activity was observed with blocks rising 500 m above the crater. Ashfall was reported in Cahuají, Manzano, and Choglontus. On 24 December roaring noises were heard and ashfall in Cahuají, Manzano, and Choglontus was reported. An ash plume rose 500 m above the crater and drifted W and SW with ashfall reported in Manzano. IG reported a decrease in activity from Tungurahua during 14-20 December. On 15 December steam plumes rose as high as 300 m above the crater and drifted W. Additional steam plumes observed on 17 December also drifted W. IG reported that during 7-8 December activity continued at Tungurahua and roaring noises and sounds resembling "cannon shots" were heard. Ash plumes rose to altitudes of 1.5-4.0 km (4,920-16,400 ft) drifting W and NE on 7 December, and W and SW on 8 December. Ashfall was reported in communities to the W, NE, and SW. On 8 December ashfall was reported in Choglontús (SW), Chacauco, Manzano (8 km SW), Bilbao (8 km W), and Pillate (8 km W). Crater incandescence was observed on 10 December, but activity decreased during 10-11 December. Based on pilot and satellite observations, the Washington VAAC reported that during 7-8 December ash plumes from Tungurahua rose to altitudes of 7.0-7.9 km (23,000 -26,000 ft) a.s.l. and drifted 18.5-24.0 km S and SW. As of the 5th of December, the eruptive activity remained at high level. The eruptive plume is still important and ashfalls occurs on the villages located to the West part of the volcano. Yesterday, several pyroclastic flows went down and travelled about 1000 m distance on the flank of the voclano. As of the 28th of November, IGEPN reported that increased seismicity from Tungurahua was detected at 1540 on 27 November, and at 1650 the seismic network recorded four volcano-tectonic earthquakes. Two small explosions at 1701 and 1705 were followed by a large explosion at 1718. Pyroclastic flows descended the Achupashal, Chotanpamba, and Mandur drainages on the NW and W flanks. Two more large explosions were detected at 1731 and 1735. Incandescent blocks traveled 1 km down the flanks, and roaring noises and sounds resembling"cannon shots" were reported. Ashfall was reported in Manzano (8 km SW), Bilbao (8 km W), and Pillate (8 km W), ash and tephra fell in Cotaló (8 km NW), and tephra fell in Cusúa (8 km NW). At 1905 a pyroclastic flow descended the S and SW flanks. Tungurahua is a steep-sided stratovolcano or a conical volcano composed of many layers of hardened lava, tephra, and volcanic ash and is located near Ecuador's fourth largest city of Ambato, some 140 km south of the capital Quito. Tungurahua - Live webcam

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ECUADOR - Reventador volcano

January 8th, 2012

IG reported that staff conducting fieldwork at Reventador during 6-7 January observed constant emissions of gas-and-steam rising about 300 m above the crater and drifting WNW. The emissions originated from a growing
lava dome that was a few tens of meters above the crater rim and almost filled the base. The IG reported that scientists conducting an overflight of Reventador on 14 July 2011 noted that the lava dome at the top of the 2008 cone continued to grow, filling the crater. The dome had reached the same height as the highest part of the crater rim, formed during 2002. Intense fumarolic activity produced continuous plumes. The dome was thought to have formed during 2011, growing at a rapid rate and producing high temperatures. IG also noted that seismicity had increased starting in May but was more pronounced during the previous few weeks. During 3-9 August cloud cover prevented observations of the lava dome, but the seismic network detected long-period and explosion-type earthquakes.Previously,based on a pilot observation, the Washington VAAC reported that on 4 January an ash plume from Reventador rose to an altitude of 5.2 km (17,000 ft) a.s.l. Cloud cover prevented clear satellite observations of the volcano. A subsequent report stated that IG noted low seismicity, no reports of ashfall, and that satellite imagery showed no ash emissions. Based on a pilot observation, the Washington VAAC reported that on 2 November an ash plume from Reventador rose to an altitude of 4.6 km (15,000 ft) a.s.l. Cloud cover prevented clear satellite observations of the volcano. Based on analyses of satellite imagery and information from IG, the Washington VAAC reported that on 6 October a small ash cloud from Reventador drifted NE. IG also reported that a steam plume rose 1 km above the crater on that same day. As of the 1st of October, IG reported that the volcan maintains a superficial seismic of moderate level, same the previous day. Activity was characterized by a moderate explosion accompanied with frequent tremor, and 7 events (LP), 12 tremor episodes , 10 episodes of harmonic tremor, 2 volcano-tectonic events. As of the 28th of September, IG reported three pulses of activity occured on the morning of 27 September: a pulse of harmonic tremor from 07:05 to 08:43 ( local times), an episode of tremor for 30 minutes from 09:07 with higher amplitude than the first pulse, and which was associated with a grey plume of water vapour with a small amount of ash that rose 400-500 metres above the summit; and a third pulse which began at 09:49 and lasted for 17 minutes and produced a grey plume of water vapour with moderate ash content, which reached higher than 1 km above the summit. As of the 24th of September, IG reported that seismic activity remained low. Today morning weather was clear and it was possible to observe emission of water steam. There were registered 9 events of long period (LP), 4 explosions, 2 episodes of tremor , 3 episodes of tremor harmonic and 2 volcano-tectonic events (VT). The Washington VAAC reported that on 9 September an ash plume from Reventador at an altitude of 5.5 km (18,000 ft) a.s.l. was observed by a pilot. The Washington VAAC reported that on 30 August an ash plume was observed near Reventador by a pilot. Ash was not seen in satellite imagery. Reventador is the most frequently active of a chain of Ecuadorian volcanoes in the Cordillera Real, well E of the principal volcanic axis. It is a forested stratovolcano that rises above the remote jungles of the western Amazon basin. A 3-km-wide caldera breached to the E was formed by edifice collapse and is partially filled by a young, unvegetated stratovolcano that rises about 1,300 m above the caldera floor. Reventador has been the source of numerous lava flows as well as explosive eruptions that were visible from Quito in historical time. Frequent lahars in this region of heavy rainfall have constructed a debris plain on the eastern floor of the caldera. (GVN/GVP)

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MONTSERRAT - Soufriere Hills volcano - West-Indies

January 27th, 2012

Reports for the period from 30th of September 2011 to 27th of January 2012- Activity at the Soufrière Hills Volcano remains at a low level. Three volcano-tectonic earthquakes were recorded by the seismic network this week from 20th to 27th of January.The average sulphur dioxide measurement over seven days this week was 343 tonnes per day with a maximum of 531 and a minimum of 247 tonnes per day. Clear weather allowed good views of the lava dome on several days this week and no changes were identified. Spots of incandescence on the lava dome, similar to those observed in recent months, were seen at night this week. A small lahar occurred on the western side of the volcano in the early hours of 27 January. One rockfall and eleven volcano-tectonic earthquakes were recorded by the seismic network this week from 13th to 20th of January. Nine of these VTs occurred in 11 minutes on 17 January. The average sulphur dioxide measurement over seven days this week was 263 tons per day with a maximum of 334 and a minimum of 164 tons per day. No significant changes in the lava dome were observed this week. One rockfall and two volcano-tectonic earthquakes were recorded by the seismic network this week from 6th to 13th of January.The average sulphur dioxide measurement over seven days this week was 340 tons per day with a maximum of 493 and a minimum of 194 tons per day. Partial glimpses of the lava dome this week showed no significant changes. Activity at the Soufrière Hills Volcano remained at a low level from 30th of December to 6th of January. The seismic network recorded one rockfall and three volcano-tectonic earthquakes this week. The average sulphur dioxide measurement over seven days this week was 325 tons per day with a maximum of 468 and a minimum of 238 tons per day. Cloudy weather prevented any views of the lava dome this week. The seismic network recorded three rockfalls and two volcano-tectonic earthquakes this week from 23rd to 30th of December. The average sulphur dioxide measurement over six days this week was 334 tons per day with a maximum of 526 and a minimum of 216 tons per day. Cloudy weather prevented good views of the lava dome this week. Despite the low level of activity, pyroclastic flows can still occur without any warning. Lahars (mudflows) also remain a hazard. Tracks across the Belham valley are frequently destroyed or heavily modified by lahars, therefore caution should be exercised crossing the valley during and after rainfall. The seismic network recorded two volcano-tectonic earthquakes and one long-period earthquake this week from 16th to 23rd of December. The average sulphur dioxide measurement over five days this week was 589 tons per day with a maximum of 1204 and a minimum of 257 tons per day. During the first half of the week, there was excellent visibility of the dome which showed no changes. Despite the low level of activity, pyroclastic flows can still occur without any warning. Lahars (mudflows) also remain a hazard. Tracks across the Belham valley are frequently destroyed or heavily modified by lahars, therefore caution should be exercised crossing the valley during and after rainfall. Activity at the Soufrière Hills Volcano remained at low level from 9th to 16th of December.The seismic network recorded five rockfalls and ten volcano-tectonic (VT) events this week. Seven of these VTs occurred over ten minutes on 14 December. The average sulphur dioxide measurement over four days this week was 742 tons per day with a maximum of 1782 and a minimum of 248 tons per day. Multiple lahars (mudflows) occurred on the southern and western sides of the volcano on 10 December associated with heavy rainfall during a thunderstorm. The seismic network recorded fourteen volcano-tectonic (VT) events previous week. Ten of these VTs occurred over 3 minutes on 6 December. The average sulphur dioxide measurement over seven days this week was 644 tons per day with a maximum of 947 and a minimum of 289 tons per day. Observations from the helicopter this week showed no fresh rockfall deposits or changes to the lava dome. Despite the low level of activity, pyroclastic flows can still occur without any warning. Lahars (mudflows) also remain a hazard. Tracks across the Belham valley are frequently destroyed or heavily modified by lahars, therefore caution should be exercised crossing the valley during and after rainfall. The seismic network recorded two rockfalls and eight volcano-tectonic (VT) events this week from 25th of November to 2nd of December. Four of these VTs occurred in one minute during the early hours of 1 December. The average sulphur dioxide measurement over seven days this week was 576 tons per day with a maximum of 657 and a minimum of 365 tons per day. Partial clear views of the dome showed no fresh rockfall deposits. Large lahars (mudflows) occurred on the southern and western side of the volcano in the early hours of 27 November. The seismic network recorded six rockfalls and six volcano-tectonic (VT) events this week from 18th to 25th of November. The average sulphur dioxide measurement over seven days this week was 527 tons per day with a maximum of 1948 and a minimum of 216 tons per day. The lower value is an underestimate owing to only one operational spectrometer earlier in the week. It is of note that 1948 tons per day is the highest daily sulphur dioxide value since September 2009. Partial clear views of the dome showed fresh rockfall deposits on the southwest side of the dome above Gingoes Ghaut and on the eastern side above the Tar River valley. Measurements made at Trants on the northeastern side of the volcano this week show that the 11 February 2010 pyroclastic flow deposits are now at temperature of 125 o C at 3.2 m depth. Despite the low level of activity, pyroclastic flows can still occur without any warning. Lahars (mudflows) also remain a hazard and caution should be exercised crossing the Belham valley during rainfall. The seismic network recorded four rockfalls and twelve volcano-tectonic (VT) events this week from 11th to 18th of November. Six of these VTs occurred in a small swarm on the morning of 18 November. The average sulphur dioxide measurement over six days this week was 257 tons per day with a maximum of 407 and a minimum of 186 tons per day. Partial clear views of the dome showed no changes in morphology. The seismic network recorded three rockfalls and six volcano-tectonic events the previous week from 4th to 11th of November.The average sulphur dioxide measurement over six days this week was 360 tons per day with a maximum of 645 and a minimum of 250 tons per day. Clear views of the dome showed no changes in morphology and no fresh rockfall deposits were identified. There was a moderate sized lahar in the Belham valley on 9 November associated with an intense thunderstorm. Caution should be exercised crossing the Belham valley during periods of heavy rain. Activity at the Soufrière Hills Volcano is still at a low level.The seismic network recorded one hybrid and six volcano-tectonic events this week from 28th of october to 4th of November.The average sulphur dioxide measurement over five days this week was 304 tons per day with a maximum of 328 and a minimum of 276 tons per day. Clear views of the dome showed no changes in morphology and there were no fresh rockfall deposits identified. Despite the low level of activity, pyroclastic flows can still occur without any warning. As of 4 November the Hazard Level is 2. There is daytime access (8:00am to 4:00pm) to Zone C. Maritime zone W remains daytime transit only (boats may sail through the zone but must not stop). The seismic network recorded ten rockfall, twelve volcano-tectonic, one hybrid and three long period events the past week from 21st to 28th of October. The average sulphur dioxide measurement over six days this week was 433 tons per day with a maximum of 614 and a minimum of 243 tons per day. Brief partial views of the dome showed no changes in morphology and there were no fresh rockfall deposits identified. The seismic network recorded one rockfall and two volcano-tectonic events this week from 14th to 21st of October.The average sulphur dioxide measurement over five days this week was 486 tons per day with a maximum of 716 and a minimum of 263 tons per day. There were no clear views of the dome this week. The seismic network recorded two rockfalls and seven volcano-tectonic events and one hybrid this week 7th to 14th of October. The average sulphur dioxide measurement over five days this week was 422 tons per day with a maximum of 657 and a minimum of 289 tons per day. There were no clear views of the dome this week. Intense rainfall generated small lahars on the western flanks of the volcano on the morning of 11 October. The seismic network recorded two rockfalls and twelve volcano-tectonic events this week from 30th of September to 7th of October. : Montserrat Volcano Observatory - View latest NOAA satellite image of Montserrat ( every 30 mn)
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MEXICO - Popocatepetl volcano

February 2nd, 2012

CENAPRED reported that during 25-31 January steam-and-gas emissions rose from Popocatépetl; some of the emissions contained moderate amounts of ash on 25 and 29 January. On 25 January an ash plume rose 3 km above the crater and drifted NE. Crater incandescence was observed at night on 29 and 31 January.
CENAPRED reported that during 18-24 January steam-and-gas emissions rose from Popocatépetl, that occasionally contained small amounts of ash during 19-22 January. On 19 January a plume rose 2.5 km above the crater and drifted NE. Crater incandescence was observed at night during 19-21 January. CENAPRED reported that during 11-17 January steam-and-gas emissions rose from Popocatépetl; the plumes contained small amounts of ash during 13-17 January. Crater incandescence was observed at night during 16-17 January. CENAPRED reported that during 4-10 January steam-and-gas emissions rose from Popocatépetl; the plumes contained small amounts of ash during 4-5 January and 8-10 January. On 5 January two explosions generated incandescence in the crater. CENAPRED reported that during 28 December-3 January steam-and-gas emissions rose from Popocatépetl and a gas plume rose to an altitude of 1 km on 28 December. Two small landslides were recorded inside the crater on 2 January. During 2-3 January gas plumes rose to an altitudes of 600-700 m above the crater and drifted NE. CENAPRED reported that during 21-27 December steam-and-gas emissions rose from Popocatépetl; the plumes contained small amounts of ash during 22-24 December. On 21 December a bluish gas plume was observed and during 22-23 December ash plumes rose 0.9-1 km above the crater. Crater incandescence was observed at night during 26-27 December. CENAPRED reported that during 14-20 December steam-and-gas emissions rose from Popocatépetl. Those emissions occasionally contained small amounts of ash on 14, 15, and 20 December. On 15 December an ash plume rose 1.2 km above the crater and drifted NE. During 18-19 December crater incandescence was observed early in the morning. An ash plume rose 900 m above the crater on 20 December CENAPRED reported that during 7-13 December steam-and-gas emissions rose from Popocatépetl and occasionally contained small amounts of ash. On 7 December ashfall was reported in San Pedro (13.5 km NW). Crater incandescence was observed during 9-11 December and on 9 December incandescence ballistic fragments were observed on the upper slopes of the cone. Based on reports from CENEPRED and the Mexico City MWO, the Washington VAAC reported an ash plume that drifted 12.9 km W on 7 December. CENAPRED reported that during 30 November-6 December steam-and-gas emissions rose from Popocatépetl and crater incandescence was observed during most nights and early mornings. Steam-and-gas emissions occasionally contained small amounts of ash on 30 November and 5 December. Based on information from the Mexico City MWO, the Washington VAAC reported that an ash plume rose to an altitude of 6.7 km (22,000 ft) a.s.l. and drifted NE on 5 December. That same day satellite imagery showed that the ash plume had dissipated CENAPRED reported that during 22-28 November steam-and-gas emissions rose from Popocatépetl and crater incandescence was observed during most nights and early mornings. Steam-and-gas emissions occasionally contained small amounts of ash on 29 November. During 16-20 November CENAPRED reported steam-and-gas emissions from Popocatépetl. A series of emissions was detected on 18 November; clouds prevented ground observations and no ashfall was reported. Based on information from the Mexico City MWO however, the Washington VAAC reported that an ash plume rose to an altitude of 7.6 km (25,000 ft) a.s.l. and drifted SW that same day. Satellite imagery showed another ash plume drifting E at an approximate altitude of 9.1 km (30,000 ft) a.s.l. CENAPRED noted that at 1201 on 20 November an explosion produced an ash plume that rose approximately 2 km above the crater and drifted N. The explosion was heard in Amecameca (19 km NW). (Video) Steam-and-gas plumes rose from the crater during 21-22 November. CENAPRED reported that during 19-23 October steam-and-gas emissions rose from Popocatépetl. Emissions during 23-25 October occasionally contained small amounts of ash. During 21-25 September CENAPRED reported steam-and-gas emissions from Popocatépetl. An explosion on 26 September ejected incandescent fragments and produced an ash plume that rose 2.5 km above the crater. Following the explosion, a series of 11 gas-and-steam plumes containing small amounts of ash rose from the crater. During 30-31 August there were 111 plumes of gas, steam, and some ash detected by the network, in addition to periods of harmonic tremor. Signals from detectors near drainages possibly indicated lahars. During 1-4 September the monitoring network registered 4-12 instances daily of emissions of gas, steam, and some ash. Periods of tremor continued to be detected. As of 30th of August at 11:00 h CENAPRED reported tha twas an increase in the activity of the volcano Popocatepetl. This has involved a greater number of low-intensity exhalations accompanied by steam, gas and small amounts of ash. The most important were presented today at 11:29 and 14:11 with an approximate height of 1 km and the winds moved west-northwest. It has been reported ashfall in the towns of cold San Pedro Nexapa and Amecameca, State of Mexico. At the time of this report remains with exhalations of steam and gas. This activity is probably from the table, ie the infiltration of water caused by recent rains in the area. As reported, this activity is within the scenarios consistent moderate exhalations, some with ash emissions, sporadic bursts of low to moderate probability of emission of incandescent fragments within walking distance of the crater and incandescent light in the crater of observable volcano at night. The activity described above does not, for the moment, a change in the volcanic alert level, so keeping the yellow light phase 2, as well as restricting access within a radius of 12 km is allowed only Xalitzintla controlled traffic between Santiago, Puebla, Paso de Cortes and San Pedro Nexapa, State of Mexico. It maintains a constant monitoring of the volcano to detect any change in behavior that could indicate a higher risk status. CENAPRED reported that late on 9 August an ash plume from Popocatépetl rose 1 km above the crater and drifted W. During 11-12 August steam-and-gas emissions occasionally contained small amounts of ash. previous news from CENAPRED reported that during 31 May-1 June steam-and-gas emissions from Popocatépetl occasionally contained small amounts of ash. At 0637 on 3 June an ash plume rose 3 km above the crater following seismic tremor. The lower-altitude portion of the plume drifted W (towards the state of Morelos) and the higher-altitude portion of the plume drifted ENE (over Puebla, 40 km E). Within a few hours ashfall was reported in the Morelos state, municipalities of Tetela del Volcán (20 km SW), Zacualpan (31 km SW), Jonacatepec (43 km SW), and Axochiapan (60 km SSW). At 2112 high-frequency, low-amplitude tremor was detected that was followed by an ash plume at 2116 that rose 1 km above the crater and drifted W. By 2130 activity had returned to normal levels. On 4 June an ash plume rose 1 km above the crater and drifted SSW at lower altitudes and NE at higher altitudes. CENAPRED reported that on 30 May an ash plume from Popocatépetl rose 800 m above the crater and drifted E. Volcano Popocatépetl, 5426 m high is located at 70 km SE of Mexico City. The glacier-clad stratovolcano contains a steep-walled, 250-450 m deep crater. Three major plinian eruptions, the most recent of which took place about 800 AD, have occurred from Popocatépetl since the mid Holocene, accompanied by pyroclastic flows and voluminous lahars that swept basins below the volcano. Frequent historical eruptions, have occurred since precolumbian time. Information from CENAPRED - Live cam of Popocatepetl -

MEXICO - Colima volcano

January 14th, 2011

According to news articles from 11 and 12 January 2011, although incandescent landslides from Colima's lava dome had increased during the last days of 2010 into early 2011, the activity was still considered to be within normal parameters. Landslides occurred on the W, S, and N flanks, producing "dust plumes" observed from multiple municipalities. The lava dome that began growing in February 2007 was about 60 m high and had a volume of 2.6 million cubic meters. PREVIOUS 2010 NEWS - Based on analyses of satellite imagery and information from the Mexico City MWO, the Washington VAAC reported that on 7 November an ash plume from Colima rose to an altitude of 6.7 km (22,000 ft) a.s.l. and drifted 19 km SW. Based on analysis of satellite imagery, the Washington VAAC reported that an ash cloud from Colima drifted W on 28 October 2010. The Colima volcanic complex is the most prominent volcanic centre of the western Mexican Volcanic Belt. It consists of two southward-younging volcanoes, Nevado de Colima (the 4320 m high point of the complex) on the north and the 3850-m-high historically active Volcán de Colima at the south. Frequent historical eruptions date back to the 16th century. Occasional major explosive eruptions (most recently in 1913) have destroyed the summit and left a deep, steep-sided crater that was slowly refilled and then overtopped by lava dome growth. Colima's web video camera - Colima data base

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GUATEMALA - Fuego volcano

January 26th, 2012

INSIVUMEH reported that during 18-19 and 23-24 January explosions from Fuego generated ash plumes that rose 200-700 m above the crater; the plumes drifted 8-15 km S, SW, and W. During 18-19 January incandescent material rose as high as 100 m above the crater and at night on 23 January incandescent explosions were observed. Block avalanches descended the S flanks. INSIVUMEH reported that during 11-13 and on 16 January explosions from Fuego generated ash plumes that rose 400-1,000 m above the crater; the plumes drifted 10-15 km in multiple directions. Explosions generated shock waves and rumbling sounds that were detected to the SW, and windows and roofs vibrated in nearby villages. Avalanches traveled SW into the Ceniza drainage and on the W, S, and SW flanks. At night on 13 and 16 January incandescence emanated from the crater. INSIVUMEH reported that on 6 and 10 January weak explosions from Fuego generated ash plumes that rose 300-600 m above the crater and drifted 10 km WNW and 15 km SW, respectively. Rumbling noises were detected several kilometers away. Incandescence emanated from the crater at night and avalanches descended the S, SW, and SE flanks. Based on information from satellite observations and INSIVUMEH, the Washington VAAC reported that an ash plume drifted SE and later dispersed on 3 January. INSIVUMEH reported that during 29 December-3 January explosions from Fuego generated ash plumes that rose 400-800 m above the crater; the plumes usually drifted SSW and WSW, but on 30 December they drifted 10 km E and NW. During the week explosions generated shock waves and rumbling sounds that were detected 10 km away. House windows and roofs vibrated in nearby villages. Incandescence emanated from the crater at night, and avalanches traveled SW into the Taniluyá and Ceniza drainages, and S in the Santa Teresa drainage during 29 December-2 January. On 3 January the wind lifted ash to an altitude of 500 m. Based on information from satellite observations, the Washington VAAC reported that a possible ash plume drifted SE on 3 January. That same day, information from INSIVUMEH and satellite imagery indicated small emissions that rose to an altitude of 4.9 km (16,000 ft) a.s.l and drifted SE. Fuego, one of Central America's most active volcanoes, is one of three large stratovolcanoes overlooking Guatemala's former capital, Antigua. Frequent vigorous historical eruptions have been recorded since 1524 and have produced major ashfalls, along with occasional pyroclastic flows and lava flows. The last major explosive eruption from Fuego took place in 1974, producing spectacular pyroclastic flows visible from Antigua. From (INSIVUMEH)

GUATEMALA - Santa Maria - Santiaguito

February 2nd, 2012

INSIVUMEH reported that active lava flows on the S and SE flanks of Santa María's Santiaguito lava-dome complex generated block avalanches on 27 and 30 January. Moderate explosions generated ash plumes that rose 700 m above the complex and drifted SW and S. Strong winds caused re-suspended ash to rise 1 km high and drift several kilometers W and S. Ashfall was reported in Monte Claro (S) and Palajunoj (SW) on 27 January. INSIVUMEH reported that active lava flows on the SE flanks of Santa María's Santiaguito lava-dome complex generated block avalanches during 18-19 and 23 January. On 19 and 23 January explosions generated ash plumes that rose 400-800 m above the complex. On 19 January ashfall was reported in communities of La Florida (5 km S), Palajunoj (SW flank), and San Marcos (46 km NW). Crater incandescence was observed at night on 23 January. INSIVUMEH reported that during 11-12 and on 16 January explosions from Santa María's Santiaguito lava-dome complex generated ash plumes that rose 600-800 m above the complex and drifted SW. Lava flows on 16 January on the SE and SW flanks generated block avalanches and rumbling noises. (scientific blog about Santiaguito). INSIVUMEH reported that on 6 and 10 January explosions Santa María's Santiaguito lava-dome complex generated ash plumes that rose 600 m above the complex and drifted N and W, respectively. Crater incandescence was observed at night and active lava flows on the SE and SW flanks generated block avalanches. Based on analyses of satellite imagery, the Washington VAAC reported that an ash plume drifted 18.5 km E of the Mexico border. INSIVUMEH reported that on 9 December plumes from Santa María's Santiaguito lava-dome complex rose 300 m above the crater and drifted SW and explosions generated rumbling noises. On 13 December block avalanche activity increased on the S flank and created pyroclastic flows that were deposited into the San Isidro drainage. INSIVUMEH reported that during 24-25 November block avalanches originated from the crater at Santa María's Santiaguito lava-dome complex as well as from lava flows. Ash plumes rose 500 m above the crater and drifted SW. During 28-29 November explosions generated shock waves and rumbling noises, as well as ash plumes that rose 700 m above the crater and drifted W. Incandescence was observed at night from Caliente dome and avalanches from lava flows descended the S and NE flanks. INSIVUMEH reported that during 1-2 November explosions from Santa María's Santiaguito lava-dome complex generated ash plumes that rose 600-1,000 m above the complex and drifted S and SW, causing ashfall in villages downwind. The explosions were heard in areas 12 km to the S and SW. Lava flows on the SE and S flanks generated block avalanches. During 3-4 and 7-8 November explosions produced ash plumes that rose 500-800 m above the complex and drifted SW and W. Explosions and rumbling were heard in areas to the S and SW. Lava flows on the SE flank continued to generate block avalanches. Based on analyses of satellite imagery, the Washington VAAC reported that during 5-6 November possible ash plumes drifted 18-28 km SE and a thermal anomaly over the volcano was detected. On 8 November a possible ash plume drifted 45 km SW, coincident with an enhanced thermal anomaly. The massive dacitic Santiaguito lava-dome complex has been growing at the base of the 1902 crater since 1922. Compound dome growth at Santa Maria has occurred episodically from four westward-younging vents, the most recent of which is Caliente. Dome growth has been accompanied by almost continuous minor explosions, with periodic lava extrusion, larger explosions, pyroclastic flows, and lahars

GUATEMALA - Pacaya volcano

January 26th, 2011

INSIVUMEH reported on 20 January that a blue plume rose from the base of the NW flank of Pacaya's MacKenney cone. The Pacaya National Park authority was advised to not allow tourists near the area with the new plume. During 21-24 January fumarolic activity in the crater had variable intensity.INSIVUMEH reported that during 5-6 January steam-and-gas plumes, white and blue in color, rose 200 m above Pacaya's MacKenney cone. Seismic activity was consistent with gas emissions.On 8, 13, and 14 December, INSIVUMEH reported that gas-and-steam plumes rose from Pacaya's MacKenney cone and drifted SE, SW, and S, respectively. During 21-22 and 26 October, INSIVUMEH reported Strombolian explosions originating from Pacaya's MacKenney crater, although the explosions were not visually observed. INSIVUMEH reported that during 2 and 4-5 October steam-and-gas plumes rose from Pacaya's MacKenney cone and drifted S. As of the 24th of September, INSIVUMEH reported that activity continues without changes in the eruptive features, only with white fumarole consisted principally from water steam to 100 meters on the crater, moving in south direction. Pacaya is a complex basaltic volcano constructed just outside the southern topographic rim of the 14 x 16 km Pleistocene Amatitlán caldera. During the past several decades, activity at Pacaya has consisted of frequent strombolian eruptions with intermittent lava flow extrusion that has partially filled in the caldera moat and armored the flanks of MacKenney cone, punctuated by occasional larger explosive eruptions that partially destroy the summit of the cone.

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COSTA RICA - Arenal volcano

August 2nd , 2011

OVSICORI-UNA reported that occasionally during early mornings in July web-camera images showed a plume rising from Arenal that drifted SE and S. Scientists that conducted fieldwork during 29-30 July 2011 observed plumes rising from the last cone that formed in the NE part of Crater C. PAST YEAR NEWS :OVSICORI-UNA reported that during November 2010, activity originating from Arenal's Crater C was at a low level and consisted of gas emissions, sporadic Strombolian eruptions, and occasional avalanches. Residents to the N, W, and S observed a decrease in gas emissions and nighttime incandescence from the crater. Acid rain and small amounts of ejected pyroclastic material affected the NE, E, and SE flanks. Crater D produced only fumarolic activity. Previously, OVSICORI-UNA reported that during September, activity originating from Arenal's Crater C was at a low level and consisted of gas emissions, sporadic Strombolian eruptions, and occasional avalanches. Residents to the N observed material ejected from Strombolian explosions descending the N flank. Acid rain and small amounts of ejected pyroclastic material affected the NE, E, and SE flanks. Crater D produced only fumarolic activity. The 1657-m-high andesitic volcano towers above the eastern shores of Lake Arenal, which has been enlarged by a hydroelectric project. Arenal lies along a volcanic chain that has migrated to the NW from the late-Pleistocene Los Perdidos lava domes through the Pleistocene-to-Holocene Chato volcano, which contains a 500-m-wide, lake-filled summit crater. The earliest known eruptions of Arenal took place about 7000 years ago, and it was active concurrently with Cerro Chato until the activity of Chato ended about 3500 years ago. Growth of Arenal has been characterised by periodic major explosive eruptions at several-hundred-year intervals and periods of lava effusion that armor the cone. Arenal's most recent eruptive period began with a major explosive eruption in 1968. Continuous explosive activity accompanied by slow lava effusion and the occasional emission of pyroclastic flows has occurred since then from vents at the summit and on the upper western flank. New webcam

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COSTA RICA- Poas Volcano

December 18th, 2011

OVSICORI-UNA reported that fieldwork at Poás on 16 December showed new geyser activity from a vent on the N flank of the lava dome that formed in 2011. A water-and-mud fountain rose 5-6 m high, flowed into the lake, and built a terrace along the S shore. Gas-and-steam plumes rose from the lava dome.OVSICORI-UNA reported that during October fumarolic activity at Poás continued with bluish gas plumes rising from the lava dome; plumes rose more than 1 km and were reported by residents in Valle Central. Towards the end of the month, the fumarolic activity as well as incandescence from the lava dome decreased. The new craters at the N base of the dome united into a crater that was 25 m long and 7-10 m wide. Phreatic activity continued to occur from Laguna Caliente, the summit lake. The lake was 55 degrees Celsius, and the level had risen 22 cm between 14 September and 27 October. As of the 2nd of September, OVSICORI reported that Since mid-July 2011, incandescence is visible during the day on the “Dome” of Poás volcano, Costa Rica, which has not happened since 1981. This observation is the most spectacular illustration of a change of activity that started several months before. Comparing data from seismic, deformation, geochemical and field measurements to the volcanic phase that occurred between 1980 and 1989, we propose two interpretations: 1) the intrusion of a fresh batch of magma although we find no evidence in the data at hand, and 2) a change in the hydrothermal plumbing system that deviated the flux from the lake to the“Dome”. Depending on the precipitation rates in the following months, possible consequences of this change of activity could be the disappearance of the lake and the enhancement of the sub-aerial emission of gases and particles into the atmosphere with a strong impact on the surrounding environment. The complete report is available here and A video illustration is available here . As of the 29th of July, OVSICORI-UNA reported that a subtle, semicircular scar (observed few months ago) progressed rapidly to a a sharp scarp on the south shore of the hot-acidic lake of Poas Volcano. Such sudden change is accompanied with incandescence at the middle steep wall of the dome neighboring the lake (near 670ºC). The 60m wide, 2.5m cliff shows degassing and geyser type activity on the west end, next to the steaming lake. Such horseshoe shapes were observed after phreatic eruptions in the early months of 2006. More details (photos and map) in this Spanish field report Previously, according to a news article, a team of geologists and volcanologists from the Universidad de Costa Rica (UCR) visited Poás on 25 May 2011 and observed 18 phreatic eruptions from Laguna Caliente (the summit lake) in a three-hour period. OVSICORI-UNA reported that during April sporadic phreatic eruptions occurred from the central part of Laguna Caliente, a summit lake of Poás. Gas plumes rose a few meters to several tens of meters above the lake surface. Solid dark material ejected from the lake fell back into it, causing small surges. The temperature of the lava dome was 560 degrees Celsius at accessible areas. Bluish fumarolic plumes rose from the dome; a gas plume rose 1 km and drifted NE, E, and SE. A small phreatic explosion occured on 2nd of February 2011 from the Crater lake producing a little mud column to about 6 meter high. OVSICORI report in spanish. Before, during, and after the eruption a concentric area of the lake surface about 15 m in diameter was disturbed by a convecting cell. Bubbles of gas rose from the agitated area and upwelling sediments were observed. Previously OVSICORI-UNA reported that during November several phreatic eruptions from the central part of Laguna Caliente, a summit lake of Poás, ejected material that fell back into the lake, occasionally producing small waves. Dark-colored gas plumes rose a few meters to several tens of meters above the lake surface. The temperature of the lava dome was 630 degrees Celsius at accessible areas. Fumarolic plumes from the dome rose 1 km and drifted W and SW. Some foliage on the SW flank, about 3.5 km from the crater, showed signs of damage from gases.OVSICORI-UNA reported that during September several phreatic eruptions from the central part of Laguna Caliente, a summit lake of Poás, ejected material that fell back into the lake. Gas plumes rose a few meters to several tens of meters above the water surface. The temperature of the lava dome was 810 degrees Celsius at accessible areas. As of the 23rd of February, OVSICORI-UNA reported that a new phreatic explosion occured on 23rd of February at 11: 33 AM (local time). Slight ashfalls occured on Southwest and Southeast flanks of the volcano. No precursor signal was recorded. As of the 28th of December, the Observatorio Vulcanológico y Sismológico de Costa Rica (OVSICORI-UNA) reported that on the 25th of December a phreatic eruption from Laguna Caliente, a summit lake of Poás, was seen by visitors standing at a viewpoint to the S of the crater. Lake water mixed with sediment and blocks was ejected 550-600 m above Laguna Caliente and fell in the vicinity of the lake, within the crater. The amount of steam emitted from lava-dome fumaroles, at the S edge of the lake, increased subsequent to the eruption. According to a local paper, a phreatic explosion occured on Friday morning, 18 September. This explosive event projected water and sediment to a height of about 300 meter above the surface of the crater lake. It is the northern of the volcano's two summmit crater lakes named Lago Caliente, which is the site of frequent phreatic eruptions; the most recent, a smaller event, was in January.The paper also mentions that scientists visiting the summit of the voclano have found burning sulphur on the north wall of the crater lake, the first time this phenomenon has been seen since 1994. Recent high temperatures and low rainfall have reduced the water volume in the highly acidic lake, and degassing from the crater has intensified with the gas plume of bright yellow' in certain areas and reaching 400 metres in height when measured on 16 September. Poás, one of the most active volcanoes of Costa Rica, contains three craters along a N-S line. The frequently visited multi-hued summit crater lakes of the basaltic-to-dacitic volcano, which is one of Costa Rica's most prominent natural landmarks, are easily accessible by vehicle from the nearby capital city of San José. A N-S-trending fissure cutting the 2,708-m-high complex stratovolcano extends to the lower northern flank, where it has produced the Congo stratovolcano and several lake-filled maars. The southernmost of the two summit crater lakes, Botos, is cold and clear and last erupted about 7,500 years ago. The more prominent geothermally heated northern lake, Laguna Caliente, is one of the world's most acidic natural lakes, with a pH of near zero.

COSTA RICA - Turrialba volcano

January 20th, 2012

During the evening of 18 January scientists observed gas emissions and ejection of tephra from the vent.
They also observed reddish flames from combusting gas, estimated to be about 700 degrees Celsius. Residents reported a dark ash cloud and ashfall in La Central (4 km SW). An OVSICORI-UNA pilot observed an ash plume that rose to altitudes of 4.3-6.1 km (14,000-20,000 ft) a.s.l. OVSICORI-UNA reported that on 11 January local people around Turrialba heard several instances of rumbling. On 12 January an eruption occurred from a fissure on the SE flank of the main crater, in an area called La Quemada. An ash plume rose 500 m above the crater and drifted NNW, rising to an altitude of 4 km (13,000 ft) a.s.l. Later that day residents reported: a dark plume from La Quemada and a white vapor plume that rose from the fumarolic vent formed in the main crater on 5 January 2010. According to a news article, the Turriabla National Park closed on 12 January and the National Emergency Commission (CNE) raised the Alert Level from Green to Yellow in the communities of La Central (34 km SW), Santa Cruz (7 km SE), and around the perimeter of the crater. Towns of Jiménez (21 km N), Oreamuno (45 km SW), Alvarado (38 km SW), and Cartago (25 km SW) remained at Alert Level Green. Previously, fieldwork on Turrialba Volcano (Costa Rica) showed a newly formed crater lake in the active west crater. OVSICORI-UNA staff reported since February 2011 an accelerated sealing process at the bottom of west crater due to frequent rock and mudslides. Sustained rains started in may provoking that water body to stay in the basin. The (70x70m), 1m deep, light green lake shows minor bubbling in the SW and NE shores due to preexistent gas outputs. Rock cracking can be heard from the other side of the crater due to the contact of hot fumarole outlets (above 370ºC) with the lower parts of the west walls. As of the 24th of January, OVSICORI reported that settlers living at the base of Turrialba volcano reported fine fallout on Friday, 14, 2011 (around 3pm, 21GMT). Due to thick cloudiness, rain and wind fieldwork was postponed. A visit, by OVSICORI staff, to the summit and surroundings (Tuesday 18th) showed rockslides from both sides of the vent opened exactly one year ago, when several phreatic eruptions took place. A singular hanging horizontal cave (lateral explosion vent ?) was formed and produced a small terrace topped with debris. Such material eventually will fall in the main vent to produce similar ejections. An elongated strip of fallout material, 2-5cms thick, (all preexistent) was observed up to 200m SW of the vent. Very fine material was sampled some 3kms SW along the lowland pastures that surround the volcano.PREVIOUSLY : the Washington VAAC reported that on 15 August 2010 ash emissions from Turrialba were seen through an OVSICORI-UNA web camera, about 600 m E of the active crater. Satellite imagery showed an approximately 10-km-wide ash plume drifting 15 km W. PREVIOUSLY : Based on web camera views of Turrialba, the Washington VAAC reported that on 24 July a plume of steam, gas, and ash drifted W. Over the next three hours the plume became more diffuse and steam-rich.As of the 20th of May, OVSICORI-UNA reported that during April a majority of the gases emitted from Turrialba originated from the vent that opened in January, producing plumes that rose 2 km. Gas was emitted from other areas including from fissures SW of the W crater and from multiple vents and fissures in the main crater. Gas plumes mainly drifted NW, W, and SW, coincident with areas that had the most vegetation impact from the plumes. As of the 18th of May, OVSICORI-UNA reported that during April a majority of the gases emitted from Turrialba originated from the vent that opened in January, producing plumes that rose 2 km. Gas was emitted from other areas including from fissures SW of the W crater and from multiple vents and fissures in the main crater. Gas plumes mainly drifted NW, W, and SW, coincident with areas that had the most vegetation impact from the plumes. OVSICORI-UNA reported that scientists visited Turrialba at night on 7 March. A gas plume, commonly seen drifting with prevailing winds, was seen that night rising 1.5 km above the crater and drifting NW. Noises from the crater were described as sounding like a jet engine and rumblings. A vent, formed in January, emitted gas at temperatures between 300 and 320 degrees Celsius. Small blocks 3-12 cm in diameter and different colors dominated the surface around the vent. Lithics ejected 30-50 m away from the vent measured 170 degrees Celsius. Incandescence seen at night originated from the vent which ejected reddish-colored tephra. As of the 3rd of february, OVSICORI reported that Turrialba, which erupted on a small scale at the beginning of January, has returned to a state of passive degassing similar to that which pertained before the eruption.However, volcanologists have warned that although activity has declined low intensity earthquakes continue, the volcano remains active and people should not be complacent. The comision Nacionale de emergency (CNE) has revised the alert level currently applied to the area surrounding the volcano, with Yellow Alert now applying to a 2 km radius zone around the volcano and Green Alert to areas beyond that limit. Previously, on 20 January 2010 an overflight of Turrialba took place which reported a revitalization of the column of gas and steam with suspended particles. A photography of the activity was taken during this overflight. A sustained emission was reported on that day, with a thick, dark plume from the summit moving WNW, the strong wind preventing the plume from rising much above the altitude of the volcano. Some light ashfall was reported in areas near the volcano. Although the transport and distribution of volcanic particles (old ash) is a new occurrence for this eruptive period of Turrialba volcano, notes the report, the minimal quantity carried this morning could be the first of much more in the near future as material eroded from the internal walls of the active conduit is carried up into the plume. After the first round of phreatic eruptions during 5-6 January from Turrialba volcano OVSICORI published the following field report : "A visit to the field on jan 6th shed light about what happened between the night of Monday 5th and early hours of Wednesday 6th. At least two vents (between 20 and 30m wide) opened along the inner walls of W crater, to eject an unestimated volume of preexistent fine particles. A narrow plume (8x40 km) of sediments moved SW up to 40 kms reaching a small portion of the populated Central Valley where most Costarricans live. Thickness of deposits vary from few mm (near the summit) to a fine sheet after some 15 km away from the volcano. Granulometry of particles vary from 1mm, in the proximal area to micras, in the distal areas. No juvenile material was found in the described deposits, on the contrary its color, shape and general aspect coincide with the openings in the upper summit. Strong degassing accompanied of fractionated material is intermittently expelled from the new vents as we write this report. Although the tremor signal decreased, compared to two preceding days, energy is enough to produce columns of several hundreds of meters above the summit. Fortunately nobody was hurt during the initial explosions and most of settlers, 3 kms around the volcano, got evacuated. Damage to crops, machinery and infrastructure has not been assessed although it is believed that it may increase if emissions persist." A low-amplitude tremor continued until 16:58 on 8 January; since that time the tremor has ended and the volcano has returned to the same LP type earthquakes that were recorded before 4 January, and now activity at the volcano has returned to the levels of before the phreatic eruption. Previously, as of the 5th of January OVSICORI reported that at 14:48 local time an inhabitant of the La Central area located to the south-west of Turrialba volcano reported hearing a strong eruption of Turrialba, much later people living near the volcano reported ashfall. Also, officials of the Parque Nacional Volcán Irazú reported the presence of ash in vehicles parked in the car park inside the national park. Additionally, residents of Turrialba, Tres Ríos and owners of properties on the slopes of Turrialba volcano reported ashfall. From mid-December 2009 until 4 January 2010, LP-type earthquakes (low frequency) had been predominantly registered, with a significant decrease of volcanic tremor. On 4 January 2010 there was a significant increase in volcanic tremor, both in duration of registration and in the amplitude of the signal. Coinciding with the increase in the recording of tremor there was a significant decrease in LP-type earthquakes. In the early hours of Wednesday 6 January an OVSICORI-UNA team will go to the area to make observations and collect data and information to carry out relevant studies. A green (preventative) alert was issued by the authorities for the area around Turrialba, and about 20 people were evacued from the volcano's slopes. Previously, a s of the 2nd of September, according to OVSICORI scientists, the volcano was showing again an increase in degazing activity. Turrialba, the easternmost of Costa Rica's Holocene volcanoes, is a large vegetated basaltic-to-dacitic stratovolcano located across a broad saddle NE of Irazú volcano overlooking the city of Cartago. The massive 3340-m-high Turrialba is exceeded in height only by Irazú, covers an area of 500 sq km, and is one of Costa Rica's most voluminous volcanoes. Three well-defined craters occur at the upper SW end of a broad 800 x 2200 m wide summit depression that is breached to the NE. Most activity at Turrialba originated from the summit vent complex, but two pyroclastic cones are located on the SW flank. Five major explosive eruptions have occurred at Turrialba during the past 3500 years. Turrialba has been quiescent since a series of explosive eruptions during the 19th century that were sometimes accompanied by pyroclastic flows. Fumarolic activity continues at the central and SW summit craters.INFORMATION from OVSICORI - SVE Volcanic fieldtrip on group request.

COSTA RICA - Rincon de la Vieja volcano

September 29th, 2011

Over the last 6 weeks Rincón de la Vieja Volcano has produced phreatic eruptions from its active crater, filled with an acidic and hot mixed lake. A well-documented event on 16 September ejected sediment that covered sections of the upper N walls. Some of the material was washed down the flanks and caused changes in water quality along the main creeks and major rivers up to 18 km away from the source. The death of several fish species was noted the next day and sediment deposits 10-15 cm deep were sampled 2 km N of the active crater. Scientists conducting fieldwork during 27-29 September observed that the hot lake was convecting and grayish in color due to the suspended sediments. Preliminary deformation and temperature measurements did not indicate any significant changes. OVSICORI Spanish report. Rincon de la Vieja, a composite stratovolcano in Northwestern Costa Rica forms a NW-trending ridge consisting of several eruptive centers that have coalesced through time. Elevations of the individual cones range from 1670 to 1920 meters and nine craters are readily identified by their topographic expression. Numerous phreatic eruptions have occurred since 1851 (as recently as November, 1995), all from the Active Crater. The last major eruption involving juvenile magma occurred at ~3,500 ybp, producing the Rio Blanco tephra deposit. Ash, pumice, and lithics ejected during this eruption were deposited in a highly asymmetrical dispersal pattern WSW of the Active Crater, indicating strong easterly prevailing tradewinds at the time of the eruption. Historical descriptions of the summit crater morphology suggest that conditions there have changed little over the past century.
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NICARAGUA - Telica volcano

May 25th, 2011

As of the 24th of May INETER reported that explosive activity was still continuing, Yesterday, 23rd of May, 8 explosions were recorded. Temperature in the summit crater increased to about 500°C. The seismicity remains shallow between 0,5 and 1 km depth. During 20-21 May activity decreased. An observer reported four
strong explosions and gas-and-tephra plumes that rose 500-700 m high. As of the 19th of May, INETER reported that explosive activity was continuing over the last few days, producing small ash plumes that reaching about 1000 m above the summit crater. along with a number of explosions that were heard across the region. Combine this with increased of the seismicity and steam and ash plume. The microseismic activity increased from the explosion occured on 18th of May at 1.50 p.m, with a 6 mn of duration accompanied by a eruption plume reaching 2,6 km high. During the past 18 h, INETER recorded 15 moderate explosions accomapnied by gas, ash and vapor and sometime with lightning. INETER reported that this activity is not really exceptional, but new fumaroles appeared on the North flank and additional monitoring equipment will be moved to the volcano soon. Evacuations of the nearby villages have not been ordered, and 12 people who live especially close to Telica were moved. As of the 13th of March, INETER reported that at about 12 pm a serie of explosions started from the summit crater accompanied with emission of gas and ash. The evEnt was recorded by the seismic station located around the volcano. From the month of April, seismicity increased with magnitude range from 0.1 to 3.3 on Richter scale , and accompanied with mild explosions. Maximum amplitude of the explosions reached 380 units RSAM. The civil defence reported that people of La Quemada, Los Patos and Palo de Lapa observed an eruptive column with red gas colour and felt earthquakes during the past days. Telica, one of Nicaragua's most active volcanoes, has erupted frequently since the beginning of the Spanish era. The Telica volcano group consists of several interlocking cones and vents with a general NW alignment. Sixteenth-century eruptions were reported at symmetrical Santa Clara volcano at the SW end of the Telica group. However, its eroded and breached crater has been covered by forests throughout historical time, and these eruptions may have originated from Telica, whose upper slopes in contrast are unvegetated. The steep-sided cone of 1061-m-high Telica is truncated by a 700-m-wide double crater; the southern crater, the source of recent eruptions, is 120 m deep. El Liston, immediately SE of Telica, has several nested craters. The fumaroles and boiling mudpots of Hervideros de San Jacinto, SE of Telica, form a prominent geothermal area frequented by tourists, and geothermal exploration has occurred nearby (GVN/GVP)

NICARAGUA - San Cristobal volcano

August 22nd, 2011

The Washington VAAC reported that on 21 August emissions of gas and light ash from San Cristóbal were possibly detected in satellite imagery drifting 35 km WNW. Ash was not detected in subsequent images.
As of the 7th of January, the Washington VAAC reported that a new eruptive gas plume rose yesterday (2:15 PM TU) above the volcano. As of the 17th of december, INETER reported that gas and ash emission continued associated with high seismicity. Previously, as of the 16th of December, Washington VAAC already reported another notable gas and ash emission. Based on analyses of satellite imagery, the Washington VAAC reported that on 20 August an ash plume from San Cristóbal drifted over 35 km N. As of the 2nd of July, INETER reported that explosions occured on Friday afternoon, 2 July 2010: two explosions from the summit crater at about 13:05 and 13:10 ejected pyroclastic material, including rocks with a diameter of up to ten metres, which caused fires in nearby grasslands. A mushroom cloud of ash was produced by the second explosion, and light ashfall occurred in villages NW of the volcano. No damage or injuries were reported. An emergency plan was activated for the areas around the volcano, but there were no further signs of activity over the weekend. The Instituto Nicaragüense de Estudios Territoriales (INETER) described Friday's activity as ‘normal degassing.The San Cristóbal volcanic complex, consisting of five principal volcanic edifices, forms the NW end of the Marrabios Range. The symmetrical 1745-m-high youngest cone, named San Cristóbal (also known as El Viejo), is Nicaragua's highest volcano and is capped by a 500 x 600 m wide crater. El Chonco, with several flank lava domes, is located 4 km to the west of San Cristóbal; it and the eroded Moyotepe volcano, 4 km to the NE of San Cristóbal, are of Pleistocene age. Volcán Casita, containing an elongated summit crater, lies immediately east of San Cristóbal and was the site of a catastrophic landslide and lahar in 1998. The Plio-Pleistocene La Pelona caldera is located at the eastern end of the San Cristóbal complex. Historical eruptions from San Cristóbal, consisting of small-to-moderate explosive activity, have been reported since the 16th century. Some other 16th-century eruptions attributed to Casita volcano are uncertain and may pertain to other Marrabios Range volcanoes.San Cristobal's last such activity occurred three years ago. GVN/GVP - NOTE : a SVE fieldtrip in Nicaragua is still planned for end November 2011 - registration open

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El SALVADOR - San Miguel volcano

March 30th, 2011

Servicio Nacional de Estudios Territoriales (SNET) reported that during a survey of the San Miguel crater on 9 and 16 March observers noted pulses of gas rising 200 m from the crater. On 12 March the number and amplitude of earthquakes increased. RSAM values rose the next day to 121 units per day on average, up from normal values around 50 units per day. RSAM values continued to fluctuate during the next few days and reached as high as 319 units on 19 March, 414 units on 20 March, and 234 on 21 March. On 18 and 20
March, local residents felt vibrations and heard minor rumbling. Observations on 25 March indicated that gas plumes rose 100 m from the crater. On 28 March SNET noted that seismicity had gradually decreased
during the previous few days, and was as low as 80 RSAM units on 27 March. Access to areas within a 2-km-radius remained restricted. The symmetrical cone of San Miguel volcano, one of the most active in El Salvador, rises from near sea level to form one of the country's most prominent landmarks. A broad, deep crater that has been frequently modified by historical eruptions (recorded since the early 16th century) caps the truncated summit of the towering volcano, which is also known locally as Chaparrastique. Radial fissures on the flanks of the basaltic volcano have fed a series of fresh lava flows, including several erupted during the 17th-19th centuries that reached beyond the base of the volcano on the N, W, and SE sides. The SE-flank lava flows are the largest and form broad sparsely vegetated lava fields.
GVN - (SNET)

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COLOMBIA - Galeras volcano

January 12th, 2012

INGEOMINAS reported that low-level activity continued at Galeras during 4-10 January, with steam rising from the main crater and two craters to the N and SW (Paisita and Chavas, respectively). The Alert Level remained at III (Yellow; "changes in the behavior of volcanic activity"). INGEOMINAS reported that activity continued at Galeras during 28 December-3 January, with steam rising from the main crater and two craters to the N and SW (Paisita and Chavas, respectively). A web camera showed gas emissions on 28, 30, and 31 December and on 1 January. The Alert Level remains at III (Yellow; "changes in the behavior of volcanic activity"). INGEOMINAS reported that activity continued at Galeras during 21-27 December, with steam rising from the main crater and two craters to the N and SW (Paisita and Chavas, respectively). The Alert Level remains at III (Yellow; "changes in the behavior of volcanic activity"). INGEOMINAS reported that activity continued at Galeras during 14-20 December, with steam rising from the main crater and two craters to the N and SW (Paisita and Chavas, respectively). The Alert Level remains at III (Yellow; "changes in the behavior of volcanic activity"). INGEOMINAS reported that activity continued at Galeras during 7-13 December, with steam rising from the main crater and two craters to the N and SW (Paisita and Chavas, respectively). On 9 and 11 December earthquakes of M 2.3 and 2.5, felt by local residents, occurred near the crater at a depth of 1.5 km. The Alert Level remains at III (Yellow; "changes in the behavior of volcanic activity"). INGEOMINAS reported that observations of Galeras during an overflight on 29 November revealed thermal anomalies in the main crater. During an overflight on 6 December scientists observed that gas emissions rose from the main crater and two craters to the N and SW (Paisita and Chavas, respectively), and had increased in comparison to the previous week. Thermal anomalies were also detected in the main crater. INGEOMINAS raised the Alert Level to III (Yellow; "changes in the behavior of volcanic activity”) on 6 December.INGEOMINAS reported that during 15-22 November steam from Galeras rose from the main crater, two craters to the N and SW (Paisita and Chavas, respectively), and a crack on the N flank of the active cone. Seismicity was at low levels, although some earthquakes were characterized as"tornillo-type." During 23-24 November the seismic network detected an emerging seismic pattern of "tornillo-type" earthquakes similar to patterns detected prior to past eruptions. Gas emissions also decreased. INGEOMINAS raised the Alert Level to II (Orange; "probable eruption in term of days or weeks") on 24 November. Previously, INGEOMINAS reported that on 31 March and 1 April emissions from Galeras were characterized by gas-and-steam plumes with low ash content. On 1 April a M 2.3 earthquake occurred 3 km E of the crater at a depth of 6 km and was felt by nearby residents. During an overflight on 2 April scientists noted a sulfur gas odor and observed that gas emissions rose from multiple areas of the active cone. Galeras, a stratovolcano with a large breached caldera located immediately west of the city of Pasto, is one of Colombia's most frequently active volcanoes. Webcam image

COLOMBIA - Nevado del Huila volcano

November 18th, 2010

According to the Washington VAAC, INGEOMINAS reported a seismic event from Nevado del Huila on 11 November consistent with a potential ash emission. A possible ash plume detected in satellite imagery drifted 25 km WSW. A subsequent notice stated that seismicity returned to background levels and the plume was no longer visible. INGEOMINAS reported that during 10-16 November whitish-colored gas plumes seen through the Tafxnú and Maravillas (12 km SE) web cameras rose 2 km above the crater. The Alert Level had been
lowered to III (Yellow; "changes in the behavior of volcanic activity") on 12 October, and remained at that level during the reporting period. Previously,the Popayán Volcano Observatory (INGEOMINAS) reported that during 29 September-5 October gas plumes from Nevado del Huila, observed with the Tafxnú and Maravillas web cameras, rose 2.5 km above the summit. Incandescence from the extruding lava dome and collapsing material was also noted. Based on a SIGMET issued from the Bogota MWO, the Washington VAAC reported that on 1 October an ash plume rose to an altitude of 7.6 km (25,000 ft) a.s.l. Later that day, a 10-km-wide gas-and-ash plume was seen in satellite imagery drifting about 30 km S. The Alert Level remained at II (Orange; "probable eruption in term of days or weeks The Popayán Volcano Observatory (INGEOMINAS) reported increased activity from Nevado del Huila on 8 and 9 September. Pulses of tremor were associated with periodic emissions of gas, ash, and incandescent material observed with the Tafxnú and Maravillas web cameras. During 8-14 September plumes of steam and occasionally ash rose as high as 2 km above the summit. The Alert Level was raised to II (Orange; “probable eruption in term of days or weeks According to the Washington VAAC, the Popayán Volcano Observatory (INGEOMINAS) received several reports from towns W of Nevado del Huila that indicated ash emissions on 30 August. Ash was not seen in satellite imagery, although extensive clouds were present in the area. A thermal anomaly was detected, however. INGEOMINAS reported that a pulse of tremor was detected, associated with an ash emission seen in the web camera at Tafxnú. Ashfall was later confirmed in Toribio, 27 km W. Nevado del Huila, the highest active volcano in Colombia, is an elongated N-S-trending volcanic chain mantled by a glacier icecap. The andesitic-dacitic volcano (5635 m) was constructed within a 10-km-wide caldera. Only a single 16th-century explosive eruption is recorded in historical time from this little known volcano. Webcam

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PERU - Ubinas volcano

June 18th, 2009

Based on SIGMET notices and analysis of satellite imagery, the Buenos Aires VAAC reported that during 11 and 13-15 June eruptions from Ubinas produced ash plumes that rose to altitudes of 5.5-7.9 km
(18,000-26,000 ft) a.s.l. Plumes drifted NE, E, and SE. Ash was not identified on satellite imagery on 13 June Based on analysis of satellite imagery, the Buenos Aires VAAC reported that on 5 June plumes from Ubinas rose to altitudes of 6.1-6.7 km (20,000-22,000 ft) a.s.l. and drifted W and S. A pilot reported that
an ash plume rose to an altitude of 7.9 km (26,000 ft) a.s.l. and drifted SW. On 6 and 9 June, plumes seen on satellite imagery rose to altitudes of 6.1-7.6 km (20,000-25,000 ft) a.s.l. and drifted S and NE, respectively. On 29 and 31 May eruptions from Ubinas produced ash plumes that rose to altitudes of 5.5-6.7 km (18,000-22,000 ft) a.s.l. and drifted NE and SW. Ash was not detected on satellite imagery on 31 May. INGEMMET reported on 1 June a bluish gas plume with some ash content. On 2 June, an explosion was detected and gas-and-ash plumes that rose 0.9-1.5 km drifted E. Ubinas in the northernmost of three young volcanoes located along a regional structural lineament about 50 km behind the main volcanic front of Peru. The upper slopes of the stratovolcano, composed primarily of Pleistocene andesitic lava flows, steepen to nearly 45 degrees. The steep-walled, 150-m-deep summit caldera contains an ash cone with a 500-m-wide funnel-shaped vent that is 200 m deep. Debris-avalanche deposits from the collapse of the SE flank of Ubinas extend 10 km from the volcano. Holocene lava flows are visible on the volcano's flanks, but historical activity, documented since the 16th century, has consisted of intermittent minor explosive eruptions.

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CHILE - Cordon Caulle-Puyehue volcano complex

February 2nd, 2012

Based on seismicity detected during 25-31 January OVDAS-SERNAGEOMIN reported that the eruption from the Cordón Caulle rift zone, part of the Puyehue-Cordón Caulle volcanic complex, continued at a low level. During 25-28 January plumes observed with a web camera rose 2-4 km above the crater and satellite images showed ash plumes drifting 90-320 km S and SE. During 29-31 January clouds prevented views. The Alert Level remained at Red. Based on seismicity detected during 18-23 January OVDAS-SERNAGEOMIN reported that the eruption from the Cordón Caulle rift zone, part of the Puyehue-Cordón Caulle volcanic complex, continued at a low level.(new Nasa satellite image). On 18, 20, and 22-23 January plumes observed with a web camera rose 2.5-7 km above the crater and satellite images showed ash plumes drifting 25-110 km NE, E, SE, and W. The Alert Level remained at Red. Based on seismicity during 11-16 January OVDAS-SERNAGEOMIN reported that the eruption from the Cordón Caulle rift zone, part of the Puyehue-Cordón Caulle volcanic complex, continued at a low level. Plumes observed with a web camera during the week rose 1-4 km above the crater, and satellite images showed ash plumes drifting 60-300 km N, NE, and SE. The Alert Level remained at Red. According to a news article, an airport cancelled all flights in and out of Bariloche, Patagonia, on 16 January because of ash plumes. An airport in Melbourne, Australia, was also forced to close due to ash from these eruptions.Based on seismicity during 6-8 January OVDAS-SERNAGEOMIN reported that the eruption from the Cordón Caulle rift zone, part of the Puyehue-Cordón Caulle volcanic complex, continued at a low level. Plumes observed with a web camera rose 2 km above the crater on 6 January. Satellite images showed ash plumes drifting 50 km S on 6 January and 300-450 km SE during 8-9 January. Clouds prevented views on the other days. The Alert Level remained at Red. Based on seismicity during 28 December-3 January, OVDAS-SERNAGEOMIN reported that the eruption from the Cordón Caulle rift zone, part of the Puyehue-Cordón Caulle volcanic complex, continued at a low level. Small incandescent explosions were observed at night during 28 December-3 January. Plumes observed with a web camera during the week rose 1-5 km above the crater. Satellite images showed ash plumes drifting 20-80 km N, NNE, NE, and SE during 28 December-3 January, dispersing ash to distances of 100-260 km. On 28 December ash fell as far away Argentina, up to 580 km SE. The Alert Level remained at Red. Based on seismicity during 21-26 December, OVDAS-SERNAGEOMIN reported that the eruption from the Cordón Caulle rift zone, part of the Puyehue-Cordón Caulle volcanic complex, continued at a low level. Small incandescent explosions were observed at night during 21-24 December. Plumes observed with a web camera during 22-23 December rose 1-2.5 km above the crater and 5 km above the crater on 26 December. Satellite images showed ash plumes drifting 20-250 km E, SE, SW, NW, and NNE during 21-26 December. Ash spread 140 km NW and 200 km NNW on 23 December, ash scattered 55 km SE on 25 December, and 100 km N and 200 km ESE on 26 December. The Alert Level remained at Red. Based on seismicity during 14-20 December, OVDAS-SERNAGEOMIN reported that the eruption from the Cordón Caulle rift zone, part of the Puyehue-Cordón Caulle volcanic complex, continued at a low level. Plumes observed with the web camera during 14-15 December rose 2.4-2.5 km above the crater and plumes were identified in satellite imagery drifting 30-50 km SE, S, and NE during 14-18. Satellite images showed ash plumes drifting 40-270 km SE, S, and NE during 14-18 December. The Alert Level remained at Red. Based on seismicity during 7-13 December, OVDAS-SERNAGEOMIN reported that the eruption from the Cordón Caulle rift zone, part of the Puyehue-Cordón Caulle volcanic complex, continued at a low level. Plumes observed with the web camera during 8-9 December rose 3.0-3.5 km above the crater and plumes were identified in satellite imagery drifting 90 km SE on 8 December and 250 km ENE on 9 December. Cloud cover prevented web camera and satellite observations during 10-13 December, but ashfall was reported to the E during 10-11 December. The Alert Level remained at Red. Based on seismicity during 30 November-6 December, OVDAS-SERNAGEOMIN reported that the eruption from the Cordón Caulle rift zone, part of the Puyehue-Cordón Caulle volcanic complex, continued at a low level. During 1-3 and 5 December plumes observed with the web camera rose 1.5-3 km above the crater. On 1 December satellite imagery showed an ash plume drifting 90 km SSE with sparse ashfall to the W and NW and dissipated 100 km to the SE. During the night the crater was incandescent. Satellite imagery showed an ash plume drifting E and SE and reaching the Atlantic Ocean on 2 December. Cloud cover prevented satellite observations during 3-4 December. On 5 December satellite imagery showed a plume drifting 100 km NW. The Alert Level remained at Red. Based on seismicity during 23-28 November, OVDAS-SERNAGEOMIN reported that the eruption from the Cordón Caulle rift zone, part of the Puyehue-Cordón Caulle volcanic complex, continued at a low level. Cloud cover prevented web camera views during 24-25 November, but satellite imagery showed a discontinuous ash plume drifting E and reaching the Atlantic Ocean on 24 November, and a fan-shaped ash plume spreading NE to SE on 25 November. Plumes observed with the web camera during 26-27 November rose 2.3-2.5 km above the crater. According to a news article, flights out of Uruguay were disrupted or cancelled on 26 November due to ash plumes. A plume observed in satellite imagery drifted 300 km E on 28 November. The Alert Level remained at Red.Based on seismicity during 16-20 November, OVDAS-SERNAGEOMIN reported that the eruption from the Cordón Caulle rift zone, part of the Puyehue-Cordón Caulle volcanic complex, continued at a low level. Cloud cover prevented web camera views on 16 November, but satellite imagery showed an ash plume drifting 100 km SW and sparse ashfall to the E. During 18-20 November plumes observed with the web camera rose 2.5-3 km above the crater. Satellite imagery showed ash clouds drifting E and SE on 18 November and an ash plume drifting 250 km SE on 19 November. During the night on 20 November the crater was incandescent. Cloud cover prevented observations on 21 November. The Alert Level remained at Red. Based on seismicity during 9-13 November, OVDAS-SERNAGEOMIN reported that the eruption from the Cordón Caulle rift zone, part of the Puyehue-Cordón Caulle volcanic complex, continued at a low level. During 9-10 November clouds prevented observations with an area web camera, but on 9 November satellite imagery showed an ash plume that drifted and dissipated to the E. During 11-12 November mostly gray plumes observed with the web camera rose 4-7 km above the crater. During the night the crater was incandescent and small explosions were observed. Satellite imagery showed ash plumes drifting 90 km NE on 11 November and 400 km SE on 12 November. Ash fell in areas on the border of Chile and Argentina at Paso Samore on 12 November. Cloud cover prevented web camera views on 13 November, but satellite imagery showed a plume drifting 250 km NE. A gray plume rose 6.5 km above the crater on 14 November. That same day a plume identified in satellite imagery drifted 200 km NW and ash clouds drifted from the SE to the NE. The Alert Level remained at Red. Based on seismicity during 3-8 November, OVDAS-SERNAGEOMIN reported that the eruption from the Cordón Caulle rift zone, part of the Puyehue-Cordón Caulle volcanic complex, continued at a low level. During 3-6 November plumes observed with an area web camera rose 5 km above the crater, and satellite imagery showed active plumes drifting 30-120 km N, NE, E, and SE. Ash plumes dispersed as far as 300 km NE and SE. Area cameras showed a plume rising 2 km above the crater on 7 November. Cloud cover prevented observations of the plume with the area camera the next day and from satellite during 7-8 November. The Alert Level remained at Red. On 30 October seismicity possibly indicated minor lava effusion. A mostly white plume rose 7.5 km above the crater and ash plumes observed in satellite imagery drifted 350 km NW and N. Ashfall was reported in Río Bueno (80 km WNW). Small incandescent explosions were observed at night during 30-31 October. A mostly white plume rose as high as 6.5 km above the crater on 31 October and ash plumes observed in satellite imagery drifted 270 km S and SSW. On 1 November satellite imagery showed an ash plume that drifted 300 km SE. The Alert Level remained at Red. Based on seismicity during 19-25 October, OVDAS-SERNAGEOMIN reported that the eruption from the Cordón Caulle rift zone, part of the Puyehue-Cordón Caulle volcanic complex, mostly continued at a low level. Seismicity did increase during the last few days of the reporting period. Plumes visible with an area web camera rose no higher than 2 km above the crater during 19-20 October. A small plume visible in satellite imagery on 19 October drifted 50 km E and a diffuse ash plume drifted 150 km NE and SE. On 20 October a small plume drifted 70 km E. At night on 22 October incandescence emanated from the crater, possibly from active lava flows reported during the previous few days. At 0311 an explosion generated a plume that rose 4.5 km above the crater as well as increased incandescence from the crater. An ash plume observed in satellite imagery drifted 120 km W and NW, and a diffuse ash plume drifted 250 km NE and SE. During the day a white plume rose 3 km above the crater. Satellite imagery showed a plume that drifted 125 km NE, then dissipated NE and SE. On 24 October, a plume rose 6 km above the crater. Satellite imagery showed a plume drifting 125 km NE and a diffuse ash plume drifting 280 km in the same direction. The next day white plumes did not rise higher than 7.5 km above the crater and satellite imagery showed a Based on seismicity during 11-12 October, OVDAS-SERNAGEOMIN reported that the eruption from the Cordón Caulle rift zone, part of the Puyehue-Cordón Caulle volcanic complex, continued at a low level. Plumes visible with an area web camera rose no higher than 4 km above the crater during 11-12 October. On 17 October a white plume rose 4.5 km above the crater and a diffuse ash plume observed in satellite imagery drifted 30 km SE. The next day, a white plume rose 3 km above the crater. Satellite imagery showed a plume drifting 50 km NE, and then later a diffuse ash plume drifting 200 km NE and SE. The Alert Level remained at Red. Based on seismicity during 5-10 October, OVDAS-SERNAGEOMIN reported that the eruption from the Cordón Caulle rift zone, part of the Puyehue-Cordón Caulle volcanic complex, continued at a low level. Plumes visible with an area web camera rose no higher than 4 km above the crater during 5-7 October and were observed in satellite imagery drifting 30-60 km SE, SW, and N. On 9 October a white plume observed with the camera rose 4 km above the crater. Satellite imagery that day showed a widely dispersed ash plume drifting E. On 10 October a plume that was mostly white, but occasionally gray, rose 3.5 km above the crater. The Alert Level remained at Red. Based on seismicity during 28 September- 4 October, OVDAS-SERNAGEOMIN reported that the eruption from the Cordón Caulle rift zone, part of the Puyehue-Cordón Caulle volcanic complex, continued at a low level. Plumes visible in satellite images drifted 30-300 km NW, NE, E, and SE during 28 September-3 October. Plumes were also observed with an area camera to rise as high as 4 km during 30 September-4 October. The Alert Level remained at Red. Based on seismicity during 21-26 September, OVDAS-SERNAGEOMIN reported that the eruption from the Cordón Caulle rift zone, part of the Puyehue-Cordón Caulle volcanic complex, continued at a low level. Plumes observed by an area camera rose 3-5 km above the crater during 21-23 and 25 September and were visible in satellite images drifted 30-300 km NE, E, and SE during 21-26 September. The Alert Level remained at Red. Based on seismicity during 14-16 and 18-20 September, OVDAS-SERNAGEOMIN reported that the eruption from the Cordón Caulle rift zone, part of the Puyehue-Cordón Caulle volcanic complex, continued at a low level. Although cloudy weather mostly prevented observations of the vent, a plume was observed in satellite imagery drifting 60 km E on 14 September, and the next day, a plume observed by an area camera rose 4 km above the crater and drifted SE. Plumes observed in satellite imagery drifted 40-70 km N and NW during 18-20 September. Plumes observed during 19-20 September by an area camera rose 3-4 km above the crater. According to a news article, on 17 September the first commercial plane landed at the airport in Bariloche, about 60 km SE, since the airport had closed on 4 June. Private planes had been occasionally using the airport since mid-July. The Alert Level remained at Red. Based on seismicity during 7-13 September, OVDAS-SERNAGEOMIN reported that the eruption from the Cordón Caulle rift zone, part of the Puyehue-Cordón Caulle volcanic complex, continued at a low level. Although cloudy weather mostly prevented observations of the vent, plumes detected in satellite imagery during 7-8, 10, and 12 September drifted 10-60 km NE, E, and SE. A plume observed by an area camera on 12 September rose less than 1 km above the crater. The next day a plume rose less than 4 km above the crater and was observed in satellite imagery drifting 35 km NE. The Alert Level remained at Red. Based on seismicity during 31 August-5 September, OVDAS-SERNAGEOMIN reported that the eruption from the Cordón Caulle rift zone, part of the Puyehue-Cordón Caulle volcanic complex, continued at a low level. Although cloudy weather mostly prevented satellite and camera observations of the vent, plumes detected in satellite imagery during 31 August-1 September drifted SE and SW. A plume observed by an area camera on 1 September rose 1 km above the crater. On 3 and 5 September plumes observed in satellite imagery drifted 30-80 km SE and E. The Alert Level remained at Red. Based on seismicity during 24-25 August, OVDAS-SERNAGEOMIN reported that the eruption from the Cordón Caulle rift zone, part of the Puyehue-Cordón Caulle volcanic complex, continued at a low level. A predominantly white plume observed by an area camera rose 1 km above the crater. The seismic network detected four explosions that caused the plume to turn gray. Ashfall was reported in Temuco. The Alert Level remained at Red. During 16-23 August, OVDAS-SERNAGEOMIN reported that seismic activity indicated the eruption from the Cordón Caulle rift zone, part of the Puyehue-Cordón Caulle volcanic complex, continued at a low level. Cloudy weather mostly prevented satellite and camera observations of the eruption during 16-17 August, however a mostly white plume was observed by an area camera rising 2 km above the crater on 16 August. A plume that was sometimes gray rose 2.5 km above the crater on 18 August. A plume observed in satellite imagery that same day drifted 200 km NW. A period of harmonic tremor that lasted about 25 minutes may have indicated lava emission. Incandescence was observed at night during 18-19 August. On 19 August a camera recorded a mostly white plume that rose 2 km above the crater. Satellite imagery showed a plume drifting 270 km NW. During an overflight, conducted by ONEMI in collaboration with the Air Force, scientists observed a white plume rising 1.4 km that was dark gray for the first few meters above the vent. Solidified lava filled up a depression around Cordón Caulle; no active lava flows were noted. On 20 August a plume that was mostly white rose 2.5 km above the crater. Two explosive events caused the plume to rise 4 km and contain a higher concentration of ash. Satellite imagery showed a plume drifting 200 km WNW on 20 August, and 500 km SE and NW on 21 August. A white plume that rose 2 km above the crater was observed on 22 August. Satellite imagery showed a very diffuse plume drifting E. The Alert Level remained at Red. During 10-14 August, OVDAS-SERNAGEOMIN reported that the eruption continued from the Cordón Caulle rift zone, part of the Puyehue-Cordón Caulle volcanic complex. Cloud cover prevented video camera observations during 10-12 August and satellite observations during 10-11 August. A diffuse plume detected in satellite imagery on 12 August drifted 150 km E. On 14 August a gray plume recorded by the camera rose 2 km above the crater, and satellite imagery showed a plume drifting 100-150 km E and SE. The Alert Level remained at Red, indicating that ashfall and lahars remain a hazard. During 3-8 August, OVDAS-SERNAGEOMIN reported that the eruption continued from the Cordón Caulle rift zone, part of the Puyehue-Cordón Caulle volcanic complex. During 3-4 August a video camera recorded plumes rising 2 km above the crater. Satellite imagery showed plumes drifting 1,000 km NE on 3 August and 700 km SE on 4 August. Cloud cover prevented video camera and satellite observations on 5 August. The next day cloud cover again prevented camera observations, though satellite imagery detected a plume that drifted 250 km E then SE. Plumes that were mostly white rose no higher than 2.5 km above the crater during 7-8 August. Satellite imagery on 7 August detected plumes that drifted 100-200 km SE. The Alert Level remained at Red. During 25 July-1 August, OVDAS-SERNAGEOMIN reported that the eruption from the Cordón Caulle rift zone, part of the Puyehue-Cordón Caulle volcanic complex, continued and seismicity indicated that the lava flow remained active. Cloud cover prevented observations by a video camera on 25 July, though satellite imagery detected a plume that drifted 200 km SE. On 26 July the camera recorded a plume that rose 2 km above the crater and incandescence up to 500 m above the crater was observed at night. Satellite imagery showed a plume drifting 100 km SE. Cloud cover again prevented camera observations during 27-28 July, but on 28 July a 150-km-long plume was observed in satellite imagery drifting SE. During 29-31 July plumes rose 2-5 km above the crater and satellite imagery showed plumes drifting 80-400 km SW, N, and NE. Incandescence was observed up to 300 m above the crater at night during 29-30 July. Cloud cover prevented observations on 1 August. The Alert Level remained at Red. OVDAS-SERNAGEOMIN reported that on 12 and 14 July cameras installed around the Puyehue-Cordón Caulle volcanic complex recorded eruption plumes that rose no higher than 2 km above the Cordón Caulle rift zone and drifted E; weather prevented observations of the plume on 13 July. Seismic activity declined significantly. On 15 July satellite imagery showed a plume drifting 80 km E and seismic signals indicated that lava started to flow again. The effusion rate increased on 16 July, however weather again prevented observations. A light gray plume on 17 July rose 2 km above the crater and was observed in satellite imagery drifting 240 km E. According to a news article, the first plane landed at the airport in Bariloche, about 100 km E, since the airport had closed on 4 June. On 18 July a gray plume rose 5 km above the crater and drifted 150 km NW. Incandescent material observed at night was ejected 500 m above the crater and lava flows continued to be active. The Alert Level remained at Red. OVDAS-SERNAGEOMIN reported that during 6-8 July cameras installed around the Puyehue-Cordón Caulle volcanic complex recorded eruption plumes that rose no higher than 2 km above the Cordón Caulle rift zone and drifted N and NE. On 6 July satellite imagery indicated that the plume drifted 75 km NE. During 7-8 July explosions recorded by the seismic network corresponded to increases in the plume height and, on 7 July, caused windows in Riñinahue to vibrate. According to news articles, numerous flights in and around Argentina and Uruguay were cancelled on 8 July and some airports had remained closed. On 9 July seismicity indicated that lava flows had ceased. During 9-11 July weather conditions prevented views of the eruption plume by cameras installed around the volcano. Based on analysis of satellite imagery, the Buenos Aires VAAC stated on 9 July that, although ash plumes rose to an altitude of 3 km (10,000 ft), activity was weakening. Ash was again detected by satellite during periods of clear weather the next day. The Alert Level remained at Red. As of the 1st of July, SERNAGEOMIN reported that seismicity is still recorded and probably the effusive is slighly continuing. The eruptive plume is still rose above the volcano, but with less ash content. General activity seems decreased but Red aler remained. As of the 29th of June, SERNAGEOMIN reported that eruptive activity is still continuing but the latest bulletin noted that the high frequency tremor disapeared during the past hours. However the explosive activity is still occurs generating a volcanic plume above the volcano. Volcanic ash from the eruption of Mt Puyehue Cordon Caulle volcano continues to cause flight disruptions. On 27 June satellite images detected a plume that was dense for 300 m then was no longer discernable due to meteorological clouds. News outlets noted that flights in New Zealand had resumed. Ashfall was periodically reported in areas downwind, including in Riñinahue (5-10 mm of ash) Llifen, Futrono, and Curarrehue on 22 June, and Riñinahue, Pucón, and Melipeuco (in the region of Araucanía) on 25 June. Although there were no new aerial observations during 22-27 June, pulses of high-intensity tremor indicated that the lava flow remained active. The Alert Level remained at 6, Red. As of the 23rd of June, SERNAGEOMIN reported that eruptive activity is still going on, but the tremor seems decreased. The eruptive ash plume rose to about 3000-4000 m above the volcano. Ashfalls occured on several small towns around the volcano ( (Riñinahue, Llifen, Futrono, Curarrehue). As of the 21st of June, SERNAGEOMIN reported that on 21 June the plume rose 3-4 km above the crater and was dark at the base. Although there were no new aerial observations, the seismic signals indicated that the lava flow remained active. News reports noted that flights were again disrupted in parts of Australia on 21 June. SERNAGEOMIN reiterated that the Alert Level remained at 6, Red. SERNAGEOMIN personnel along with regional authorities flew over Puyehue-Cordón Caulle on 20 June. They observed a viscous lava flow with concentric morphology, confirming speculation of magma ascent reflected in seismic data from the previous few days. A 50-m-wide lava flow from the emissions center had traveled 200 m NW and 100 m NE, filling up a depression. A white plume that was gray at the base rose 3-4 km above the crater. Devastated vegetation from pyroclastic flows was observed near the basin of the Nilahue and Abutment rivers. Pulses of tremor were detected by the seismic network. Cameras installed around the volcano showed the plume, which was periodically very dark, rising 5-6 km above the crater As of the 17th of June, SERNAGEOMIN reported that eruptive activity is still going on. During the past two days an important volcanic tremor was recorded not directly related with explosive activity.Yesterday, the eruptive plume rose to about 3000 m high. As of the 14th of June, SERNAGEOMIN reported that explosive activity is still continuing. The eruptive plume rose at about 900m high during strong eruptive phase then drop during quiet activity. These intermittent phase are in relation with variation in the volcanic tremor. Pyroclastics flows generated by the column collapse occured on the upper part of the Rio Nilahue. On 14 June explosions generated pyroclastic flows (that traveled N), wereassociated ash-and-gas plumes. Based on analysis of satellite imagery, the VAAC stated that ash plumes rose to altitudes of 5.5-7.6 km (18,000-25,000 ft) a.s.l. while previously emitted ash plumes drifted NE, E, and SE at altitudes of 0.9-3 km (3,000-10,000 ft) a.s.l. SERNAGEOMIN reiterated that the Alert Level remained at 6, Red.As of the 10th of June early morning, activity was still continuing. the seismicity slighly increased during the past hours, but the eruptive plume is less important. According to Enrique Valdivio the National director of SERNAGEOMIN, the eruption started on an eruptive fissure 3 km long located on the Cordon Caulle at about 8km from Northwest of the Puyehue volcano. As of the 8th of June, SERNAGEOMIN-OVDAS reported that eruptive and seismic activity was still going on but decreased since the day before. Now, the volcanic plume rose to about 7,5 km high. According local scientists several pyroclastics flows occured on 6th of June and traveled sometimes 10km from the volcano. However the eruption is still causing problems for people living inthe zone where ash and pumice is falling. The plume itself is spreading to the north and east of the volcano. On 7 June the VAAC reported continuous emissions. Ash plumes rose to altitudes of 5.5-9.8 km (18,000-32,000 ft) a.s.l. and were 65-95 km wide. A large area of ash continued to drift E over the Atlantic Ocean. News articles noted that some flights in Paraguay and Chile were cancelled and about 4,000 people had evacuated. OVDAS-SERNAGEOMIN reported that between 2000 on 2 June and 1959 on 3 June about 1,450 earthquakes at Puyehue-Cordón Caulle were detected, or an average of about 60 earthquakes per hour. The earthquakes were mostly hybrid and long-period, and located in the SE sector of the Cordón Caulle rift zone at depths of 2-5 km. SERNAGEOMIN scientists along with regional authorities flew over the volcano, noting no significant changes. The Alert Level remained at 4, Yellow. Area residents reported feeling earthquakes during the evening of 3 June through the morning of 4 June. For a six-hour period on 4 June, seismicity increased to an average of 230 earthquakes per hour, at depths of 1-4 km. About 12 events were magnitudes greater than 4, and 50 events were magnitudes greater than 3. The Alert Level was raised to 5, Red. According to SERNAGEOMIN-OVDAS a significant eruption started on Saturday 4th of June at 3:30 PM (local time). The explosive eruption of the the Puyehue-Cordon Caulle volcanic chain generated a large eruptive column that rose to about 10 km high and important ashfalls on a popular ski resort in neighboring Argentina. Ash rapidly darkeness the sky in San Carlos de Bariloche and the airport had been closed. Chile's government was evacuating 3,500 people from the surrounding area as a precaution. Officials reported that the volcano was spitting molten rock, but there was no visible lava flow. Photos . As of the 5th of June, the eruptive activity was continuing with ejection of pumice stones accompanied with an ash column six miles (10 kilometers) high and three miles (five kilometers) wide. Flights in the region were canceled and more than 3,500 people stayed away from their homes near the volcano, which produced an eerie show of lightning dancing through its clouds of ash overnight. On Monday morning 6th of June the eruptive activity was still continuing and charaterized by a high ash plume rose to 10 km high observed with GOES images and strenchhing toward the East-South- East. The Puyehue-Cordón Caulle volcanic complex (PCCVC) is a large NW-SE-trending late-Pleistocene to Holocene basaltic-to-rhyolitic transverse volcanic chain SE of Lago Ranco. The 1799-m-high Pleistocene Cordillera Nevada caldera lies at the NW end, separated from Puyehue stratovolcano at the SE end by the Cordón Caulle fissure complex. The Pleistocene Mencheca volcano with Holocene flank cones lies NE of Puyehue. The basaltic-to-rhyolitic Puyehue volcano is the most geochemically diverse of the PCCVC. The flat-topped, 2236-m-high Puyehue volcano was constructed above a 5-km-wide caldera and is capped by a 2.4-km-wide summit caldera of Holocene age. Lava flows and domes of mostly rhyolitic composition are found on the eastern flank of Puyehue. Historical eruptions originally attributed to Puyehue, including major eruptions in 1921-22 and 1960, are now known to be from the Cordón Caulle rift zone. The Cordón Caulle geothermal area, occupying a 6 x 13 km wide volcano-tectonic depression, is the largest active geothermal area of the southern Andes volcanic zone. (GVP/GVN)

CHILE - Chaiten volcano

May 24th, 2011

As of the 24th of May, SERNAGEOMIN reported that SERNAGEOMIN reported that during 2011 seismic activity from Chaitén remained low and that no growth of the lava-dome complex was detected. Visual
observations indicated low emissions. The Alert Level was lowered to Green, Level 2, on a three-color scale.
SERNAGEOMIN reported that during 1-14 January 2011cameras installed around Chaitén's caldera rim, as well as cameras in Pumalin Park and Chaitén town, showed degassing from the lava-dome complex. Gas plumes composed primarily of water vapor rose at most 800 m above the complex. Incandescence on the surface of the dome was observed at night. The Alert Level remained at Yellow Level 3, on a three-color scale.As of the 12th of November 2010, SERNAGEOMIN reported that although seismic events at Chaitén's lava-dome complex continued to increase in the previous weeks, the magnitudes of the earthquakes remained relatively low. Gas-and-steam plumes rose 300-400 m above the caldera rim. Based on analyses of satellite imagery and web camera footage, the Buenos Aires VAAC reported that on 13 November a gas-and-ash plume rose to an altitude of 1.5 km (5,000 ft) a.s.l. and drifted 40 km SE. On 15 November ash plumes observed through the web camera rose to altitudes of 1.8-2.1 km (6,000-7,000 ft) a.s.l. and drifted E. The Alert Level remained Yellow Level 3 on a three-color scale. As of the 6th of November, based on analyses of satellite imagery and web camera footage, the Buenos Aires VAAC reported that an ash plume from Chaitén's lava-dome complex rose to an altitude of 1.8 km (6,000 ft) a.s.l. on 4 November and drifted 25 km NE. Cloud cover prevented clear satellite views of the volcano in subsequent images. As of the 1st of October, SERNAGEOMIN reported that remained active but quiet: a slight increase in seismic activity was registered during 20-28 September compared to levels earlier in the month, but the energy released by the volcanic system remains at relatively low levels, comparable to earlier months. SERNAGEOMIN is maintaining an alert level of Yellow level 3. Previously, based on analyses of satellite imagery and web camera footage, the Buenos Aires VAAC reported that a plume from Chaitén's lava-dome complex drifted 20 km ENE on 30 July. An 18-km-wide ash plume also drifted 45 km ESE. Based on analyses of satellite imagery, the Buenos Aires VAAC reported that an ash plume from Chaitén's lava-dome complex drifted 70 km SSE on 24 July. Meteorological cloud cover in subsequent images prevented further detection of the plume. PREVIOUSLY : as of the 20th of March, SERNAGEOMIN reported that on the 17th of March during the previous few weeks, growth of Chaitén's lava-dome complex was concentrated in the W part. Gas-and-ash plumes, seen through the video camera located on the rim of the caldera, rose at most 1 km from the central area of the domes. Seismic activity persisted at a low level. The Alert Level remained at Red. Based on web camera views and analyses of satellite imagery, the Buenos Aires VAAC reported that a diffuse ash plume from Chaitén's lava-dome complex, likely mixed with steam and gas, drifted NE on 15 March. As of the 18th of February, SERNAGEOMIN reported that on 11 February, ODVAS-SERNAGEOMIN reported that a camera, installed 800 m from the centre of Chaitén's lava-dome complex in late January, showed incandescence and gas emissions on the 28th of January. Seismicity had also increased during 21 January-3 February. The Alert Level remained at Red. Based on web camera views and analyses of satellite imagery, the Buenos Aires VAAC reported that a steam-and-gas plume drifted 25 km NW on the 11th of February at an altitude of 2.4 km (8,000 ft) a.s.l. During 5-19 January the lava-dome complex continued to grow, although possibly at rates lower than during previous weeks. The magnitude and number of hybrid earthquakes decreased. The Alert Level remained at Red. As of the 3rd of December, SERNAGEOMIN reported that based on analyses of satellite imagery, the Buenos Aires VAAC reported that on 26 November a diffuse plume from Chaitén's lava-dome complex drifted ENE. SERNAGEOMIN suggests maintaining Volcanic Red Alert. As of the 25th of November 2009, SERNAGEOMIN reported that Chaitén's seismic activity has remained similar to that of the preceding period, with a prevalence of hybrid type (HB) earthquakes reaching an average of 15 earthquakes per hour and with magnitudes locally calculated to be within the range 1.5 to 4.2. Among these 2-4 earthquakes stand out each hour with magnitudes of above 3.5. Comparing the seismicity of this period with that of previous weeks, the seismic energy liberated RSAM has not exceeded 150,000 units. Both visually and seismically no large changes have been shown, and activity is consistent with that which has developed during the preceding period; this indicates that the eruptive activity continues with the growth of the dome complex. On the other hand, the quantity of pyroclastic material both from rock falls and emitted by the block-and-ash flows and lateral explosions has created large accumulations in the adjacent valleys and particularly the valley of the Chaitén river, so that the occurrence of lahars towards Chaitén during periods of intense rain cannot be ruled out. In consequence, given that the seismicity remains at elevated levels – an effect of the growth of the dome complex – and that the eruptive activity continues with the possibility of the generation of block-and-ash flows in random directions, which may affect surrounding valleys with the generation of new lahars, SERNAGEOMIN suggests maintaining Volcanic Red Alert. As of the 19th of November, SERNAGEOMIN reported that during 31 October-1 November Chaitén's lava-dome complex produced steam plumes that sometimes contained gas and ash. The plumes were visible on the web camera and rose at most 1 km above the lava domes. SERNAGEOMIN bulletin of the Chaitén eruption, covering the period 16-30 September 2009, reported the results of an overflight carried out on 29 September. Among the interesting facts reported there is the emergence of a new third lava dome, the appearance of an elongated depression in the central area of the dome complex, and a collapse event on 29 September. As of the 1st of October, SERNAGEOMIN reported that based on web camera views and analyses of satellite imagery, the Buenos Aires VAAC reported that on 28 September a diffuse ash plume from Chaitén's Domo Nuevo 1 and Domo Nuevo 2 lava-dome complex, possibly mixed with steam and gas, rose to an altitude of 2.4 km (8,000 ft) a.s.l. The plume drifted less than 40 km W and SW. As of the 24th of September, SERNAGEOMIN reported that during 1-16 September, Domo Nuevo 1 and Domo Nuevo 2 lava-dome complex continued to grow. The Alert Level remained at Red. Based on web camera views, SIGMET notices, and analyses of satellite imagery, the Buenos Aires VAAC reported that during 16 and 20-22 September ash plumes rose to altitudes of 1.8-2.4 km (6,000-8,000 ft) a.s.l. and drifted NE, E, and SE A s of the 21st of August, SERNAGEOMIN reported that the images observed through the DGAC camera, located in Chaitén to the south of the volcano, show that the eruption has continued in an unchanging form with its column of gas and ash which has occasionally risen to 1.5 km above the dome complex. At times it has been possible to distinguish a secondary and intermittent centre of emission to the west, very close to the principal centre of emission. The block-and-ash flows still persist, indicating that the dome complex continues its growth, particularly towards the western sector of the caldera. .As of the 6th of August, SERNAGEOMIN reported that based on web camera views from the S, and analyses of satellite imagery, the Buenos Aires VAAC reported that during 29 July-1 August, and on 4 August, ash plumes from Chaitén's Domo Nuevo 1 and Domo Nuevo 2 lava-dome complex rose to altitudes of 1.8-2.4 km (6,000-8,000 ft) a.s.l. and drifted N, S, and SE. As of the 26th of July, SERNAGEOMIN reported that seismicity has remained high at Chaiten volcano, Chile, during the period 16-22 July. The eruption continues unchanged with a column of ash and steam rising 1.5 km above the summit. Block and ash flows still persist, indicating the dome complex has continued to grow, particularly towards the western sector of the caldera. Some strong emissions of gas correlated with seismic activity. Dome collapse remains a danger and may affect adjacent valleys. Significant pyroclastic material has accumulated in the adjacent valleys, and pose a lahar risk after heavy rain. Alert level RED remains at Chaiten volcano due to continued dome growth, pyroclastic flow risk, and potential for lahars. The Alert Level remained at Red. Based on web camera views, analysis of satellite imagery, and a SIGMET notice, the Buenos Aires VAAC reported that on 11 and 14 June ash plumes from Chaitén's Domo Nuevo 1 and Domo Nuevo 2 lava-dome complex rose to altitudes of 1.8-2.4 km (6,000-8,000 ft) a.s.l. and drifted NE and SE. A thermal anomaly was also seen in satellite imagery on 11 June. Based on web camera views, SERNAGEOMIN reported that during 27 May-8 June gas-and-ash plumes rose 1.5 km from Chaitén's growing Domo Nuevo 1 and Domo Nuevo 2 lava-dome complex. Collapses originating from unstable slopes generated block-and-ash flows that were sometimes seen from Chaitén town, 10 km SW. Ashfall was occasionally reported in Chaitén town and nearby areas. As of the 13rd of May SERNAGEOMIN reported that during 29 April-4 May gas-and-ash plumes rose up to 2 km from Chaitén's growing Domo Nuevo 1 and Domo Nuevo 2 lava-dome complex. Collapses originating from unstable slopes generated block-and-ash flows. An overflight on 1 May revealed a large central spine fractured into three main blocks. The surface of the lava dome complex was very irregular and several spines had grown 100 m above the dome surface. Seismicity remained high. Based on analysis of satellite imagery, SIGMET notices, web camera views, and information from the Puerto Montt Flight Information Region (FIR), the Buenos Aires VAAC reported that during 5 and 10-12 May, ash plumes rose to altitudes of 2.1-4.6 km a.s.l. and drifted N, NE,and ENE. According to SERNAGEOMIN, since 15 April, when the energy released by the seismicity of Chaitén volcano reached 130000 units RSAM, the values have begun to fall slightly, remaining during Thursday 16 April 2009 at 100000 units, therefore values continuing to be very elevated. Llaima, however, has not shown visual signs of significant activity during past days. As of the 2nd of April, the Government of Chile has announced that during 17-23 March Chaitén's lava-dome complex continued to grow from an area that includes the central spines and part of Domo Nuevo 1. This was also the main area where collapses from unstable slopes caused block-and-ash flows. Continuously emitted steam plumes with varying amounts of tephra and gas-and-ash plumes generated by block-and-ash flows drifted N and ESE. The block-and-ash flow volume was smaller compared to the previous week. The Alert Level remained at Red. As of the 19th of March, the Government of Chile has announced that based on web camera views, analysis of satellite imagery, and SIGMET notices, the Buenos Aires VAAC reported that during 11-15 March ash plumes from Chaitén rose to altitudes of 2.1-3.7 km (7,000-12,000 ft) a.s.l. and drifted NNE, NE, E, and SE. A thermal anomaly was detected in satellite imagery on 15 March. On 3 March during an overflight co-ordinated with the Regional Office of ONEMI it was possible to verify that the deposits of the block-and-ash flow that descended through the río Chaitén on 19 February still maintaind high temperatures in some areas, with emanations of water vapour and even burning of trees where they had come into contact with lava blocks from the domes, with high temperatures (over 300ºC). The seismicity of Chaitén volcano has declined slightly during the period in the number of larger HB-type earthquakes, with magnitudes of between 3.2 and 3.6, in comparison to previous days. The earthquakes that have been recorded are principally of HB-type, which indicates the continuing supply of magma to the dome complex. As of the 27th of february, SERNAGEOMIN reported that another large-scale dome collapsep at Chaitén volcano during the afternoon. Reports mention that a large part of the northern side of the dome collapsed and an intense plume rose from the volcano. This collapse occurred at around 14:47 local time this afternoon. An overflight carried out on 24 February, allowed the ovbservatin of the current state of eruptive activity, the morphology of the domes and the dimensions and precise location of the area affected by the collapse that occurred last Thursday (19.02.09). The escarpment or scar of the collapse is oriented in an approximately south-western direction, with a greatest length of approximately 500m and a maximum height of the of the escarpment slopes of 200m. The area of collapse is located in the south-western quadrant of the dome complex and affects, approximately, some 10% of the total volume. The collapse escarpment surrounds the south and west of the spine or pinnacle which has grown in the central sector of the dome complex. The majority of the material removed is from Dome 1, the development of which began in May 2008. The northern sector of the dome showed occasional eruptive activity, which is concentrated to the immediate north of the pinnacle, at the pinnacle, and at a remnant of dome 1 located to the south of the collapse escarpment. In the northern sector, within dome 2, eruptive activity was observed in two sectors and was manifested in the emission of water vapour with occasional ash content. The majority of the eruptive activity was concentrated on the spine or pinnacle, with constant emissions of brown-coloured ash and water vapour. The southern remnant of dome 1 intermittently emitted ash and water vapour of similar colouring to that at the pinnacle, in addition to producing sporadic explosions. Together, they form four eruption columns of gas and ash, which exceed 1.5km in height and which during small collapses of the steep slopes of the pinnacle tend to form one wide and irregular column.As of the 19 th of February, SERNAGEOMIN reported that there was a major reactivation of the eruption at Chaitén volcano on the morning. Everyone still in the town of Chaitén was evacuated, and the authorities have activated their various emergency plans. A major partial dome collapse occured, generating pyroclastic flows that penetrated a long way south along the Chaitén river valley, almost reaching the town itself. A collapse such as this is a process rather than an event, and further collapses of the structure of the dome(s), along with the release of overpressurized gases, is continuing to generate further debris flows along the length of the valley. At 15:20 the same day, an overflight was carried out at Chaitén volcano, revealing a fracture of more than a kilometre on the dome, southern sector, with evident signs of collapse, which constitutes, an important threat to the town of Chaitén. Large emissions of gases and pyroclasts were also observed. Heavy rains over the volcano could generate substantial floods, causing further damage in the town of Chaitén. Previously on 19th of January, between 10:59 and 12:00, a major partial collapse already occured on the steep pinnacles that form the summit of New Dome 2 above the south-eastern flank, with the consequent generation of block and ash flows. On 25th and 28th December, ash emissions reached 2 km above the crater. A lava dome continues to grow in the crater, producing instability on the summit and flanks. Explosions from the lava dome are possible and create the risk of pyroclastic flows. The volcano remains at the highest alert level red. As of the 15th of December SERNAGEOMIN reported that explosive events that have characterized Chaitén's recent activity took place yesterday, 14 December 2008, beginning at around 13:19 local time. The explosion, which appears to have been related to a partial collapse within the caldera, generated a large ash plume which reached hundreds of kilometres south-east into Argentine territory As of the 11th of December, SERNAGEOMIN reported that based on on observations of satellite imagery, pilot reports, SIGMET notices, and web camera views, the Buenos Aires VAAC reported that during 3-8 December, ash plumes from Chaitén rose to altitudes 1.8-4.6 km (6,000-15,000 ft) a.s.l. and drifted NE, NW, and SW. A thermal anomaly was detected on satellite imagery during 4 and 6-8 December. Gaseous emissions have been observed both from the growing New Dome 2 (north-east sector) and from New Dome 1, on its southern flank, which has almost completely covered the old dome. The emissions have shown a predominance of water vapour, even when occasional increases in the emission of volcanic gases have been seen, with changes in the colour of the columns emitted from New Dome 2, depending on variations in the concentration of ash. The columns of gases observed have reached heights of between 1.5 and 2.5 kilometres above the domes.On Saturday 6 December an overflight of Chaitén volcano was carried out and In the interior of the Chaitén caldera it was possible to see clearly the remnants of the old dome, almost completely buried by the viscous lava of New Dome 1 (coloured red-brown). Very notable were the dimensions reached by New Dome 2 (colour grey) located in the north-east sector of New Dome 1, where the eruptive activity was concentrated, consistent with the evident extrusions of viscous lava forming very unstable pinnacles and ridges, with constant landslides on their sloping sides, which rest on the internal wall of the caldera. Additionally, from two points on its uneven crest, constant emissions of volcanic gases are generated, with a predominance of water vapour. On 29 October, SERNAGEOMIN received reports of an increase in activity at Chaitén characterized by several explosions that darkened the plume and caused it to rise from about 1.6 km (5,200 ft) a.s.l to about 3.1 km (10,200 ft) a.s.l. SERNAGEOMIN reported that variations in seismicity remained similar to patterns detected during the pervious weeks. A gas plume was continually emitted to an altitude of 3.1 km (10,200 ft) a.s.l. during the previous week. ONEMI reported that during an overflight on 30 October, scientists observed a landslide that had originated from the active lava dome. As of the 20th of October, SERNAGEOMIN published a new report for the period between 13th -17th of October : during this period two eruptive columns have been maintained of no more than 2.0km in height, principally formed of water vapour with a relatively low content of sulphur dioxide and ash, moderately vigorous, white and relatively wide, with dispersion mainly towards the southeast. HB-type earthquakes are continuing without variation in quantity and magnitude. The eruptive activity is related to degassing and the generation of water vapour through rainwater coming into contact with the hot dome and/or remnants of magmatic material in the upper levels of the system. The seismic activity is related to the growth of the dome. In the short term, a possible reactivation of the eruptive process can be ruled out. SERNAGEOMIN maintains Volcanic Red Alert.SERNAGEOMIN reported that during 7-13 October a gas-and-ash plume from Chaitén rose to an altitude of 3.1 km (10,200 ft) a.s.l. The Volcanic Alert level remained at Red. Based on web camera views, Puerto Montt Flight Information Region (FIR) notices, analysis of satellite imagery, and SIGMET reports, the Buenos Aires VAAC reported that during 12-14 October, continuous ash plumes from Chaitén rose to altitudes of 2.4-4 km(8,000-13,000 ft) a.s.l. and drifted N and E. As of the 9 th of October, SERNAGEOMIN reported that during an overflight on 30 September, scientists observed the small lagoon that remained in a depression in the N area of the basal "ring" that lies between the new lava dome and the caldera rim. The base of the S flank of the old lava dome was still evident; fumaroles were noted along the contact of the old and new domes. The new lava dome had grown higher and laterally from the NE flank until it touched the caldera rim. The Alert level remained Red. Based on pilot observations, analysis of satellite imagery, and SIGMET reports, the Buenos Aires VAAC reported that during 3 and 5-8 October continuous ash plumes rose to altitudes of 2.4-3.5 km (8,000-11,500 ft) a.s.l. and drifted NE, ENE, and E. As of the 29th of September, SERNAGEOMIN reported that eruptive activity returned to levels comparable to those reported in previous days up to the end of last week, that is with columns of a maximum of 1.5km in altitude, weak and of little vigour, with a predominance of water vapour over gases and ashes, dispersing towards the north-east. Since the 26th of this month, the earthquakes of greater magnitude, interpreted as HB-type, have increased their energy to reach, in some cases, magnitude 3.5M. The earthquakes of HB-type recorded by the stations in the vicinity of the volcano (e.g. Pumalín, Pillán and Santa Bárbara) remain at depths calculated as approximately between 2.0 and 5.0km, with epicentres located, also about, at 3.0km south of the volcano. The earthquakes of greater magnitude have been registered as far as the seismic monitoring stations at Llaima volcano, located 457km to the north. SERNAGEOMIN maintains Volcanic Red Alert. SERNAGEOMIN report on the eruptive activity of Chaitén volcano between 23 and 24 September 2008 noted that eruptive activity contines with a column that does not exceed 1.5km in altitude, with a predominance of water vapour over pyroclastic materials, principally ash. A level of 3-4 HB-type earthquakes per hour has been maintained, some with magnitudes around 3.0M, and there have been sporadic small VT-type earthquakes, under 1.0M. The HB earthquakes reflect magmatic activity and the fracturing of rock, probably in superficial levels of the system - it is hoped to clarify the precise depth very soon. SERNAGEOMIN maintains Volcanic Red Alert.From Saturday 6 September until Monday 8 September, poor weather conditions did not permit visual observation. During this period, the seismicity has remained mainly similar to that recorded during the two previous weeks, that is 6 to 8 HB-type earthquakes per hour with a slight oscillation in their amplitude, and 1 to 2 VT-type earthquakes per hour, with maximum magnitude of 2.9M, in addition to rare LP-type earthquakes of low energy and short duration. Both the HB and VT earthquakes have presented very similar times of arrival of 's-p' waves, which establish distances of 23-25km from PUMA station and 15-16km from STBA, placing their epicentres 2-5km south-east of the volcano. As of the 4th of September, SERNAGEOMIN reported that clouds obscured camera views of Chaitén's eruption plume during most of 26-29 August. Glimpses utilising the web camera revealed that continuous ash plumes rose to an altitude of 1.5 km (4,900 ft) a.s.l. and drifted SW. They also reported that seismicity had increased slightly during the previous few days. Based on web camera views and analysis of satellite imagery, the Buenos Aires VAAC reported that during 27-29 August ash plumes rose to altitudes of 1.8-3 km (6,000-10,000 ft) a.s.l. and drifted SE. Between 27 and 29 August, seismic activity continued, showing a slight but steady increase. On both 28 and 29 August the increase mentioned was reflected mainly in an increase in amplitude of the HB-type earthquakes (increased seismic energy), which maintained relatively constant numbers (about 4 events per hour). For their part, the VT-type earthquakes showed a slight decline (one per hour). However, during these days, significant LP-type earthquakes were registered (about 5 per day), which are emphasized by their greater amplitude in the seismogram As of the 28th of August, SERNAGEOMIN reported that on web camera views, pilot observations, and analysis of satellite imagery, the Buenos Aires VAAC reported that during 20-23 and 26 August ash plumes from Chaitén rose to altitudes of 2.1-3 km (7,000-10,000 ft) a.s.l. and drifted SE, E, and NE. A thermal anomaly over the lava dome was detected on satellite imagery during 22-23 August. As of the 22nd of August, SERNAGEOMIN reported that during recent days the eruptive activity of Chaitén volcano has remained without major changes, manifesting itself through a moderately vigorous eruption column, of around 2km altitude, with emission of pyroclastics material, gases and water vapour. The seismic behaviour of the emission centre, for its part, has presented a decreasing trend, without resulting in a significant diminution of the eruptive activity, as in previous periods. Notwithstanding the foregoing, the recorded seismic movements could be interpreted as indicative of the movement of magmatic fluids and rupturing of rocks inside the volcanic system. SERNAGEOMIN bulletin about the Chaitén issued on 12 August 2008 reported that poor weather conditions preventing direct observation of the volcano, except on the morning of 8 August when a continuous emission of gas and pyroclasts was observed ‘which generated an eruptive column of more than 1 kilometre in height that dispersed towards the east. An increase in the number and magnitude of volcanic-tectonic (VT) earthquakes was recorded over the preceding 24 hours, along with a 'sporadic appearance' of hybrid (HB) and long period (LP) earthquakes and an increase in background tremor, ‘phenomena attributed principally to the ascent of magmatic fluids'. The bulletin ends by suggesting that the characteristics of this seismic behaviour can be interpreted as indicators of internal activity within the system that, eventually, could manifest in increases in the eruptive activity of the volcano. Following a meeting, USGS/USAID reported some details about the activity until end of July and in particularly there is fresh information on the lava dome :giving the following estimates for the end of July: average lava dome eruption rate ~60m 3 /s (the average given in June was ~37m 3 /s), area ~1.4 million m 2 (area given in June ~540,000m 2 ) volume ~350 million m 3 (volume given in June ~55 million m 3 ) - Previous news reportd that an explosive eruption appears to have taken place at Chaitén on 1st of August in the morning. This was the webcam image at 08:59 (local time): a sizeable eruption under way at the caldera. More following images indicated that the eruption has subsided, with a lighter, thinner plume (but still larger than anything we saw yesterday) and less evidence of heavy ash content. The latest bulletin (issued this same day at 11:20 local time, noted that an overflight yesterday ‘detected partial collapses in the central part of the new dome' and the removal (through collapse) of some of the material of the dome. As of the 29 th of July, SERNAGEOMIN reported that, available records indicate weak eruptive activity, which has shown a modest upswing in the last few days without giving rise to a significant eruption column. In general terms, the declining trend appears to continue on course. The weather conditions have not permitted observation of the volcano, except for short periods in which the cloud has left uncovered an eruption column that does not surpass a kilometre in altitude above the summit of Chaitén. Moreover, intense and continuous noise has been perceptible since 24 July, when an emission of ash accumulated to the depth of 3cm around Chaitén. On 27 July weather conditions again favoured the fall of fine ash on the town, albeit in a very restricted manner. The foregoing notwithstanding, the latest seismic data clearly shows an elevated seismicity, which has been sustained for several weeks, both in the number of earthquakes and their magnitude (a large number of them being felt by people over several days) and recorded by stations at a distance, with an increase in the number of earthquakes with a magnitude greater than 3.5M. Likewise, it was possible to verify that the greater part of the earthquakes of greater energy were located to the south-east and south-south-east of the Chaitén volcano. On 24 July, during an overflight conducted over sectors north and north-east of Chaitén volcano, it was observed that there is only one principal eruptive centre in the southern sector of the new dome. This centre produces an intermittent eruption column, with periodical increased activity which forms a more substantial column, although one lacking density and of relatively low altitude (less than 2km) whch disperses rapidly towards the south and south-east. That column caused poor visibility at altitude, and was occasionally crossed by more energetic and denser columns, related to slightly more intense explosions alternating with the intervals of lesser eruptive power which did not produce any proper column. The emission in this case was white in colour, mainly produced by degassification and water vapour, with a low percentage of ashes. It was also apparent that the morphology of the new dome has changed, presenting a major depression in the southern sector, immediately to the north of the principal eruption centre from which abundant water vapour and gases are emitted. At the same time, this structure [i.e. the new dome] appears to have decreased its rate of growth, at least in the northern sector, and significant emissions of water vapour and gases can be observed from the base of the eastern sector of the dome. Regarding seismic activity, during 24 July there was a decrease in the total number of earthquakes and a stabilization, it appears, in the number of earthquakes of greater magnitude. Notwithstanding the foregoing, earthquakes of this type are still being detected by instruments located nearly 300km from the volcano. The significant increase in earthquakes of greater magnitude (greater than 2.6) may imply that the ascent of a new pulse of magma has begun, from depths greater than 10km. Previously, based on observations during an overflight on 17 June, scientists of SERNAGEOMIN reported that ash plumes emitted from the S contact between Chaitén's old and new lava domes rose to an altitude of 2 km (6,600 ft) a.s.l. and drifted N and NW. An explosion temporarily propelled the ash plume to an altitude of 3 km (10,000 ft) a.s.l. and steam plumes rose from several other contact points along the S edge of the lava dome. Rockfalls from the active dome continued to descend the S flank of the old dome to the caldera floor. During 18-21 June, visual observations were inhibited due to inclement weather. During 18-20 June, possible ashfall was reported in Queilén (about 70 km W) and Quellón (about 80 km WSW). Ashfall was reported in Chaitén town (10 km SW) and other areas SE, W, and E. Another overflight on 14 June revealed spines rising above the top of the new lava dome, which had grown in height to exceed the old dome. Gas, ash, and steam plumes were primarily emitted from a vent, about 100 m in diameter, at the SE contact between the old and the new lava dome. Previously, emissions came from the NW contact between the old and new domes. Continuous explosions produced ash plumes that rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted E. Several other points of gas-and-steam emissions were seen along the contact. Small block-and-ash flows from the new dome had descended the S flank of the old dome and occasionally reached the caldera floor. The Alert Level remained at Red Chaitén volcano in southern Chile has now been erupting for six weeks, and seemed over the last few days to be still active. However, latest reports suggest renewed gas and ash emissions, loud rumbles, and the appearance of two new craters. According to a new bulletin issued by SERNAGEOMIN during evening. On 13 June 2008 the Volcano Disaster Assistance Program of the USGS gave further information about the Chaitén eruption that Some of the interesting points to emerged as follows : current lava dome eruption rate estimated to be greater than 50m 3 /s (average ~37m 3 /s); area : 540.000 m2 (900 x 600 m); volume : about 55 million m3. On 12 June people stationed in the town of Chaitén reported new emissions of gas and pyroclasts coming from the south flank of the old volcanic dome and ‘reported that noises were heard coming from the volcano during 11 and 12 June. The source of the emissions was identified as two new craters at the base of the southern flank of the old dome. The Chaitén river produced renewed flooding in the town on the evening of 12 June. The seismic activity increased after the morning of 12 June, both in the number of earthquakes and in the seismic energy that they released. The majority of the earthquakes of less than magnitude 2 were located under the volcano, while two more significant earthquakes were located 5km to the north-east, with epicentres located on one of the lines of the Liquiñe-Ofqui fault system. As of the 10th of June SERNAGEOMIN that in the last few days, the eruptive activity of Chaitén volcano has remained in patterns similar to those reported during the previous week, that is to say, the volcano continues, but with low intensity. The dome currently maintains its rapid growth and, probably, will continue in this way for weeks or months. The explosivity and discharges of ash have gradually decreased and are now manifested only in a dispersion plume which does not exceed 3km in altitude, without a true eruption column, accompanied by abundant emissions of water vapour. As of the 3rd of June SERNAGEOMIN reported that during Sunday 1 June, because of the distribution of the plume, fine ash and volcanic dust was precipitated across the central-eastern area of Chiloé island (Queilen, Lelbún, Chonchi, Dalcahue and Castro), among other areas. Due to these conditions it proved impossible to advance the consolidation of the seismic monitoring network. On Monday 2 June a dense fog affected the Corcovado Gulf, and especially the coastal area of continental Chiloé, due to the stirring up of the ashfall by the wind. However, a distant inspection flight by helicopter showed that the volcano's eruption column was reaching an altitude of no more than 3km above sea level and that the plume was dispersed in a south-south-easterly direction. Seismic activity shows a slight increase in comparison with previous days, reflected in a larger number of VT [volcano-tectonic] earthquakes and LP [long period] type earthquakes. The latter are interpreted as being caused by the movement of fluids and/or pressurization in the upper conduit. Thus, from 1 to 2 June Auchemó and Santa Bárbara seismic stations registered an average of 5 VT-type earthquakes per hour, with magnitudes of less than 2. In addition both stations observed, although in a very sporadic form, LP-type events of short duration (less than 60 seconds). As of the 26th of May SERNAGEOMIN reported that the eruptive activity of the Chaitén volcano has declined to subplinian type, but remains continuous', and that over the weekend, and in particular on Sunday 25 May, the eruption column reached an average altitude of less than 3.5km above sea level, with occasional large explosions lifting it to around 5km above sea level. South-westerly winds pushed the plume in a north-easterly direction.An overflight took place on 24 May, during which it was possible to overfly the volcano's crater and examine the slight growth of the active volcanic dome, which just rises above the summmit of the old dome'. South of the active dome is a 200-metre crater ‘from which there is a continual expulsion of gas and ash'. The new dome ‘generates, especially to the north, flows and blocks of ash, because of the instability of its steep walls'. A second overflight carried out by a Navy helicopter on 25 May revealed that many of the rivers in the Chaitén region are carrying significant quantities of ash. Seismic activity is currently declining over the past four days VT-type [volcano-tectonic] earthquakes have decreased gradually in number and magnitude, indicating a slight but steady decay of seismic activity.As of the 22nd of May, the Servicio Nacional de Geología y Minería reported, following an overflight of Chaitén volcano, that the eruptive activity of the Andean massif continues and that a phase of dome construction has begun inside the active crater. The current increase in seismicity corresponds to small internal collapses in this dome. The burden of pyroclastic material being carried by the Río Blanco will continue to be deposited on the city of Chaitén. Since yesterday the remote monitoring instruments installed by the U.S. Geological Survey (USGS) in Chumilden and Auchemó are in operation, jointly monitored from Queilén by the USGS and SERNAGEOMIN. All the people evacuated from the town of Chaitén who were in shelters have been relocated to rented houses or cabins in the cities of Puerto Montt, Osorno, Castro and Quellón. Previous news - 16th of May: t he plinian eruptive activity of the volcano Chaitén is continuing, and over the last two days the column of gases and ashes has been maintained at an altitude not exceeding five kilometres above sea level. Chaitén volcano showed increased activity onThursday 15 May 2008, with heavy ashfall, loud noises and many earthquakes. At 07:30, the upper section of the volcano's eruption column was observed, reaching an altitude of four kilometres above sea level. The plume was directed towards the north-east due to strong south-westerly winds of up to 140 km/h. Since late yesterday a light ashfall has been occurring in some sectors of Chiloé Island, principally affecting the islands of Butacheque, Metaluf, Quenac and Tac and the communes of Quemchi, Achao, Castro, Chonchi and Queilen. Municipal teams are distributing masks in the sectors concerned. The Oficina Nacional de Emergencia (ONEMI) reported that military personnel in Chaitén ‘perceived loud noises coming from the volcano, abundant ashfalls and electrical discharges around the top of the mountain'. Heavy cloud cover and rainfall prevented observation of the eruption cloud. The ONEMI bulletin also confirms earlier reports that 90% of the town of Chaitén is flooded.An Oficina Nacional de Emergencia (ONEMI) bulletin was released late yesterday, 12 May 2008. The volcano was still producing a large eruption column, which at the time of the bulletin was being blown to the north-east. It is expected that the wind will back to the north-west for the next few days, changing the alignment of the eruption plume, towards the south-east. This means that Futaleufú is in danger of further ashfalls. The volcano remains continually active with emissions of ash toward the north-east. An overflight by SERNAGEOMIN during this afternoon indicated that the eruption column reaches a height of 8 kms. For the next few days  the skies are expected to be filled with rain and north-west winds of 40-60 km/hr, meaning that the ashes will be displaced towards the south-east affecting the Futaleufú area and Argentina, according to information provided by the Dirección Meteorológica de Chile. The bulletin also notes that the Chaitén River (or Río Blanco), which crosses the city, broke its banks for a distance of about 200 metres and flooded 40 homes. The entire mouth of the river is blocked by ash and pumice. The flow of the river has now returned to normal levels. Previous information : as of the 9th of May the Chaitén volcano continues to erupt ash and the 50 kilometres security exclusion zone around the volcano remained in force, reported ONEMI in a bulletin of 9 May 2008. On 8 May the volcano was hidden from view between 07:15 and 15:15 hrs. During this period, despite the low cloud cover, grey swirls were clearly seen along the north-south valley immediately east of the volcano Chaitén which drains into the Rayas river, descending towards the river and producing marked evaporation in the north-south valley. This phenomenon is interpreted as being caused by small pyroclastic flows that descend from the volcano into this valley and, heating the river water, produce the resulting evaporation. Between approximately 15:00 and 16:30 hours the prevalent cloud dissipated allowing observation of the volcano and the mushroom-shaped column of gases and ashes, which reached an altitude of 14 km at 16:00 hrs, with a plume dispersing in a north-eastern direction. Moreover, the western part of the column of ash was more dense and of a medium to dark grey colour, which could be due to the opening of a new crater on the western side of the dome. Previous information reported that t he Chilean volcano Chaitén intensified its activity around midnight on Wednesday 7th/8th of May expelling ash and incandescent material, forcing the evacuation of all the military personnel and about 10 civilians who remained in the town closest to the peak. In the southern town of Chaitén, only 10km from the volcano, the total evacuation was ordered after pyroclastic material was seen to emerge from the cone of the volcano for a few minutes followed by dense columns of ash that fell on the surrounding area. ‘Army personnel have seen pyroclastic material, incandescent material, and there has been an increase in the sulphurous smell present in the town of Chaitén. As of 6th of May, latest SERNAGEOMIN bulletin online reported that eruptions continue for at Chaitén volcano. There have also been reports of a sharp increase in earthquakes in the area since the eruption. Evacuations have occurred at a second town, Futaleufu. Some residents have evacuated across the border to Argentina. Around 25,000 head of cattle in the area are in serious danger of dying. According to SERNAGEOMIN, during the morning of 6 May, at 08:20, the eruptive cycle went through a recrudescence with vigorous and rhythmic explosions of great energy producing a much wider laterally expanding eruptive column of about 30 kilometres altitude in its initial phase, declining subsequently. A subsequent helicopter overflight found that two craters on the northern side of the dome had joined into one, 800m-wide vent during this eruptive phase. (Assuming, as appears to be the case from photographs, that the initial site of the eruption was on the southern flank of the dome, it now seems that the volcano is erupting from both northern and southern flanks.) No pyroclastic flows were reported to the north, south or west (the eastern zone could not be inspected, presumably, being obscured by the eruption plume), and it was noted that the rivers around the volcano were carrying a greater load of erupted material. Overall SERNAGEOMIN considers that the eruption may develop in two ways from this point onwards - although, as always with predictions of volcanic activity, it is impossible to be sure. There is the possibility of a collapse of the eruptive column and/or the rhyolite dome, which would generate pyroclastic flows. On the other hand the fall of ashes may continue with accumulations whose thickness will depend on the intensity of the explosions and the prevailing winds. President Michelle Bachelet briefly visited Chaiten and spoke with some of the few remaining residents. At shelters in Puerto Montt, evacuees sought the president's support to rebuild outside the path of the volcano. Most of Chaiten's 4500 residents fled as the eruption polluted air and water supplies. As of 3rd of May bulletin, from the Chilean Government Emergencies Office ONEMI reported that eruptive activity was continued at the Chaitén volcano, with the sky darkened by ash and a constant fall of fine ash in nearby areas. A sulphurous smell has been reported in some districts. A number of earthquakes have also been experienced in the region over the past 24 hours. The volcano was still ‘erupting ashes' and covering the surrounding districts ‘with a dense cloud of ash more than 20km in height … In Chaitén town, the streets are covered with 20-40cm of ash'. The fall of ash from Chaitén is also causing problems in neighbouring areas of Argentina, where airports and schools have been closed, transport disrupted and water supplies affected. In the same bulletin ONEMI also reports that the evacuation of Chaitén is continuing, with the aim being to evacuate the whole population: From yesterday to dawn today a total of 3900 people have been evacuated by sea from Chaitén to Puerto Montt and Castro, which corresponds to 89% of the population … Today approximately 500 people will be evacuated on six vessels bound for Castro and Puerto Montt. This will evacuate the entire population of Chaitén. Previous news : following a short seismic crisis, the Chaiten volcano started an eruption. The Chaiten volcano ejected gas and ash on Thursday night 1st to 2nd of May 2008, causing more than 60 small tremors in the Los Lagos region, 750 miles south of the capital, Santiago.Chile's government declared a state of emergency, evacuating as many as 1,500 people from nearby villages and the town of Chaiten, just over 6 miles from the volcano considered dormant for thousands of years erupted. The blast sent minor earthquakes rippling through the region. The amount of ash falling in Chaiten had dropped considerably by Friday afternoon, and the wind was moving it southeast. Ash from the eruption was polluting water supplies and prompting officials to hand out more than 10,000 protective masks. Winds also carried ash over the Andes mountains to neighboring Argentina, where the Education Ministry suspended classes in several towns, including Esquel and Trevelin - two popular Patagonian tourist. Authorities also declared a state of alert on two major highways as falling ash reduced visibility. On Friday evening a Volcanic Ash Advisory stated that ash rose to altitudes in the range of 13.7-16.7 km. Chaiten lies slightly to the W of Minchinmavida. Chaiten volcano lacks any known modern eruptions but a radiocarbon date on its tephra (CHA1) yields a date of 7,430 BC (plus or minus 75 years). Chaitén is a small, glacier-free late-Pleistocene caldera with a Holocene lava dome located 10 km NE of the town of Chaitén on the Gulf of Corcovado. The north side of the rhyolitic, 962-m-high obsidian lava dome occupying the 3.5-km-wide caldera is unvegetated. Obsidian cobbles from this dome found in the Blanco River are the source of prehistorical artifacts from archaeological sites along the Pacific coast as far as 400 km away from the volcano to the north and south. The caldera is breached on the SW side by a river that drains to the bay of Chaitén, and the high point on its southern rim reaches 1,122 m. Two small lakes occupy the caldera floor on the west and north sides of the lava dome.Informations : ONEMI, GVN/GVP - SERNAGEOMIN (in spanish) - Live web camera

CHILE - Lascar volcano

January 10th , 2012

As of the 10th of January, OVDAS-SERNAGEOMIN reported increased seismicity at Láscar on 5 January and
raised the Alert Level from Green to Yellow. On 8 January ONEMI authorities warned residents about the new Alert Level status and restricted residents from going within a 20-km radius of the volcano. Lascar is the most active volcano of the northern Chilean Andes. The andesitic-to-dacitic stratovolcano contains six overlapping
summit craters and lies 5 km W of an older, higher stratovolcano, Volcán Aguas Calientes. Lascar consists of two major edifices; activity began at the eastern volcano and then shifted to the western cone. The largest
eruption of Lascar took place about 26,500 years ago, and following the eruption of the Tumbres scoria flow about 9,000 years ago, activity shifted back to the eastern edifice, where three overlapping craters were formed. Frequent small-to-moderate explosive eruptions have been recorded from Lascar in historical time since the mid-19th century, along with periodic larger eruptions that produced ashfall hundreds of kilometers away from the volcano. The largest historical eruption of Lascar took place in 1993 and produced pyroclastic flows that extended up to 8.5 km NW of the summit.(GVN/GVP)

CHILE - Planchon Peteroa volcano

June 30h, 2011

Based on SIGMET notices, the Buenos Aires VAAC reported that during 24-25 June ash plumes from Planchón-Peteroa rose to an altitude of 4.6 km (15,000 ft) a.s.l. and drifted W, NE, and E. On 27 June satellite imagery showed a gas-and-steam plume, possibly containing ash, drifting 110 km NW. SERNAGEOMIN reported that during 1-15 April a camera installed in Romeral, approximately 61 km NW of Planchón-Peteroa, recorded predominantly white vapor plumes that rose at most 600 m. During 16-19, 21 and 25-29 April episodes of ash-plume production changed from discreet plumes to more continuous emissions. Ash plumes during 17-19 and 29 April rose 1.2 km and contained ash- to lapilli-sized particles. During overflights on 26, 27, and 29 April, a geologist noted that the crater geometry and fumarolic activity had changed very little during the previous few months and that ash emissions drifted mainly SW. SERNAGEOMIN stated that because ash-and-gas emissions were becoming almost continuous, the Alert Level was raised to Level 3, Yellow on 29 April. Based on analyses of satellite imagery, SIGMET notices, and ODVAS web camera observations, the Buenos Aires VAAC reported that during 2-3 May gas-and-ash plumes rose to altitudes of 4.6-5.5 km (15,000-18,000 ft) a.s.l. and drifted NE and E. Based on a SIGMET notice, the Buenos Aires VAAC reported that on 17 April an ash plume from Planchón-Peteroa rose to an altitude of 4.6 km (15,000 ft) a.s.l. and drifted NE. Ash was not observed in satellite imagery. Based on a SIGMET notice, the Buenos Aires VAAC reported ash from an eruption of Planchón-Peteroa on 26 March. Ash was not observed in satellite imagery.Based on SIGMET notices, the Buenos Aires VAAC reported that during 17-18 March ash plumes from Planchón-Peteroa rose to altitudes of 3-4.3 km (10,000-14,000 ft) a.s.l. and drifted SE. On 18 March a diffuse steam-and-gas plume was visible in the ODVAS web camera.Based on SIGMET notices, the Buenos Aires VAAC reported that on 17 February an ash plume from Planchón-Peteroa rose to altitudes of 3-4.3 km (10,000-14,000 ft) a.s.l. and drifted SE. On 11 November, SERNAGEOMIN reported that seismicity from Planchón-Peteroa remained low. Observations from multiple sources, including a web camera and satellite images, showed that the height of the gas plume was lower than the previously reported height of 200 m, observed during 15-25 October. The Alert Level was lowered to 2, Green. As of the 30th of October SERNAGEOMIN reported that during 15-25 October seismic activity from Planchón-Peteroa was low. Observations based on images from a camera installed in the town of Romeral (approximately 60 km NW) and photos sent by staff from a mining company (65 km WNW) showed that plume color changed from gray to white on 13 October. The plume was smaller, with heights of less than 200 m above the crater. Satellite imagery analyses corroborated the ground-based observations. On 27 October, the Alert Level was lowered to 3, Yellow. Based on analyses of satellite imagery, pilot observations, and SIGMET notices, the Buenos Aires VAAC reported that during 6-12 October ash plumes from Planchón-Peteroa rose to altitudes of 3-6.1 km (10,000-20,000 ft) a.s.l. and drifted in multiple directions. The Alert Level remained at 4, Yellow. Based on analyses of satellite imagery, pilot observations, and SIGMET notices, the Buenos Aires VAAC reported that during 30 September-3 October ash plumes from Planchón-Peteroa rose to altitudes of 3-6.1 km (10,000-20,000 ft) a.s.l. and drifted NW, NNE, E, and SE. The SERNAGEOMIN bulletin covering the period 16-30 September, reported that data from monitoring of the volcano indicates that the current activity wascharacterized by the active presence of a body of magma, interacting with the upper hydrothermal system of the volcano, which continues in a minor eruptive process. A high level of seismic activity has been recorded, associated with fluid movements in the interior of the volcano. including a continuous tremor signal. An overflight on 30 September revealed that the volcano is continuing to produced pyroclastic eruptive activity of a low intensity, but that there has been a ‘slight increase in the vigour of the emissions compared with that seen over the last three weeks' Based on analyses of satellite imagery, the Buenos Aires VAAC reported that on 26 September an ash plume from Planchón-Peteroa rose to an altitude of 4.3 km (14,000 ft) a.s.l. and drifted SSE. According to NASA's Earth Observatory, a satellite image of Planchón-Peteroa shows an ash plume drifting 22 km SE on 18 September and ashfall on the snow beneath the plume. The Buenos Aires VAAC reported that according to a SIGMET issued on 21 September an ash plume rose to an altitude of 6.1 km (20,000 ft) a.s.l and drifted SE. Ash was not identified in satellite imagery. The Alert Level remained at 4, Yellow. As of the 13th of September, SERNAGEOMIN reported that the current activity at the volcano appears to be quietening. The volcano's emissions contain more steam and less ash, and there is no evidence of fresh magmatic material.Since last Sunday 10 September the fumarolic activity at Planchón volcano has shown a tendency towards a greater content of water vapour and, apparently, has progressively carried less ash content. Analysis of ash samples has found no juvenile components, which suggests that fresh magma has played no part in the [eruptive] process. Seismicity has also been at a low level over the period 9-12 September, and no earthquakes were recorded associated with internal fluid movements. This implies that the activity associated with the processes is very superficial. As of the 9th of September, SERNAGEOMIN published a bulletin, reporting observation during an overflight of the volcanic complex .On the basis of the overflight of the area of the Planchón-Peteroa volcanic complex carried out on 7 September local scientists concluded that Planchón volcano is maintaining eruptive activity with weak explosions, possibly of phreatomagmatic origin, similar to minor phases of the eruption recorded in 1991. The currently active crater is the south-western, which has for several years usually shown persistent fumarolic activity. The present eruptive activity shows local accumulations of ash in the area within 10 km around the volcano and no alterations have been observed in the glaciers of the volcanic complex. The activity is consisting of discrete pulses of gases and fine ash with a frequency of between 40 and 60 seconds. These emissions create a weak eruptive column of grey colour rising up to about 200 metres above the crater, which then disperses towards Argentine territory, to the east of the volcano. The current activity does not present a hazard to the local population, but continuous monitoring of the volcano will be carried out for as long as the activity continues. Planchón-Peteroa is currently at alert level 4 Yellow. Previous news : as of the 8th of September 2010, Chile's state geological service SERNAGEOMIN reported  that the Planchon Peteroa volcano, on the border between Argentina and Chile, started erupting in the past few days, spewing pyroclastic material and gases. The plume yesterday reached as high as three-quarters of a mile above the crater. According to SERNAGEOMIN, the present eruptive activity is characterized by mild explosions with a component phreatic-vulcanian (solid material) from the acid lakes area of the craters .During the day of 6 September the eruptive column was drifted mainly East. Same day at 06:47 a.m. local time (10:47 GMT) Servicio Sismológico Nacional registered an earthquake (mag 5,2 - 13,4 km depth) and localized at about 9 km SE of the volcanic group. Planchón-Peteroa is an elongated complex volcano (4107 m) along the Chile-Argentina border with several overlapping calderas. Activity began in the Pleistocene with construction of the basaltic-andesite to dacitic Volcán Azufre, followed by formation of basaltic and basaltic-andesite Volcán Planchón, 6 km to the N. About 11,500 years ago, much of Azufre and part of Planchón collapsed, forming the massive Río Teno debris avalanche, which reached Chile's Central Valley. Subsequently, Volcán Planchón II was formed. The youngest volcano, andesitic and basaltic-andesite Volcá Peteroa, consists of scattered vents between Azufre and Planchón. Peteroa has been active into historical time and contains a small steaming crater lake. Historical eruptions from the Planchón-Peteroa complex have been dominantly explosive, although lava flows were erupted in 1837 and 1937.Last known activity was reported in 1998 (GVN). The volcano, 121 miles south of Santiago, has had a permanent plume of smoke for several years.(further details as soon as possible) - SERNAGEOMIN

CHILE - Villarica volcano

October 2nd, 2011

According to Projecto Observación Visual Volcán Villarrica (POVI), an image from 17 September showed the inner SSW wall of the crater covered with snow and ice, and a thin layer of ash. A rapid rise in the level of the lava column (in a pit about 40 m wide) on 19 September caused much of the snow and ice to melt, especially on the southern inner wall. Strombolian explosions from the crater were observed on 26 September, and tephradeposits on the E edge of the crater were noted. On 27 September incandescence from the lava column were reflected in the cloud cover above. Glacier-clad Villarrica, one of Chile's most active volcanoes, rises above the lake and town of the same name. It is the westernmost of three large stratovolcanoes that trend perpendicular to the Andean chain. A 6-km wide caldera formed during the late Pleistocene. A 2-km-wide caldera that formed about 3500 years ago is located at the base of the presently active, dominantly basaltic to basaltic-andesitic cone at the NW margin of the Pleistocene caldera. More than 30 scoria cones and fissure vents dot Villarrica's flanks. Plinian eruptions and pyroclastic flows that have extended up to 20 km from the volcano have been produced during the Holocene. Lava flows up to 18 km long have issued from summit and flank vents. Historical eruptions, documented since 1558, have consisted largely of mild-to-moderate explosive activity with occasional lava effusion. Glaciers cover 40 sq km of the volcano, and lahars have damaged towns on its flanks.(GVN/GVP)

CHILE - Hudson volcano

November 18th, 2011

OVDAS-SERNAGEOMIN reported that satellite imagery and an area web camera showed no plumes rising from Cerro Hudson during 7-15 November. Seismic activity decreased significantly, reaching a low level characterized by no more than four earthquakes per hour and the absence of tremor. The Alert Level remained at Yellow, Level 4. On 2 November, OVDAS-SERNAGEOMIN reported that the Alert Level for Cerro Hudson was lowered to Yellow, Level 4, noting that the eruption that began on 26 October had ceased. ONEMI reported that the 140 evacuees were permitted to return home. Analysis of ash deposited on the edge of the crater during the eruption indicated the presence of juvenile basalt. During 1-6 November between 16 and 110 earthquakes per day were recorded and satellite images showed drifting plumes daily During an observation flight on 30 October, scientists saw plumes with minor ash rising 0.8 km from two of the three craters. ONEMI noted that the total number of evacuees had reached 140. On 31 October scientists observed gas plumes rising 0.5 km above the craters and drifting SE. On 1 November scientists observed an explosion and an accompanying ash plume that rose 1.5 km above the active craters. They also noted subsequent minor explosions and ash emissions. As of the 28th of October, ONEMI andauthorities asserted that the risk of a large eruption from the Hudson has decreased after a reduction in the amount of steam and ash being expelled from the volcano.However, the government will continue with its efforts to evacuate the surrounding area as a precautionary measure. During an overflight on 28 October, scientists observed a gas plume with a very low ash content rise 3-4 km above the craters. Seismicity continued to decrease during 28-29 October. Scientists conducting an overflight noted that a gas plume with some ash rose 1 km above the craters and drifted 5-8 km NE. They also confirmed that a large lahar had traveled down the Rio Huemul and another branch of the river during the initial phase of the eruption. OVDAS-SERNAGEOMIN reported three new craters at Cerro Hudson following increased seismicity that was detected during 25-26 October. At 1908 on 25 October an M 4.6 volcano-tectonic earthquake occurred at a depth of 19 km, followed by a seismic swarm starting at 2149. More than 100 events, with depths ranging from 15 to 25 km, were recorded through the next day; 12 of the events were M 3, and three events were M 4. Scientists aboard an overflight on 26 October observed a white plume with some ash content that rose 1.5 km and lahars in Rio Huemul, to the W. The Alert Level was raised to Level 5 - Red. A very low-frequency M 4.3 earthquake occurred that same day at a depth of 15 km. Five earthquakes per hour were recorded between 1600 on 26 October and 1600 on 27 October. Most of the earthquakes were volcano-tectonic events with magnitudes lower that 3.6 and located W of the caldera at depths between 3 and 25 km. The earthquake hypocenters became shallower with time. The most significant event, a M 3.6, occurred at 0227 on 27 October and was located in the SW edge of the crater. Very low-frequency earthquakes possibly indicated magma movement.SERNAGEOMIN staff aboard an overflight on 27 October observed three craters along the S, SE edge of the caldera, with diameters of 200, 300, and 500 m. Mostly white plumes rose above the two smaller craters. The larger, southern-most crater emitted a plume with a greater ash content that rose 5 km above the crater. Satellite imagery showed a plume drifting 12 km SE. In response to the raised Alert Level, ONEMI reported that 128 people were evacuated from areas within a 45-km radius of the volcano, defined as high-risk zone. One earthquake per hour was recorded between 1600 on 27 October and 1600 on 28 October. The majority of the earthquakes were characterized as long-period with magnitudes less than 2.2.   Ice-filled, 10-km-wide caldera of the remote Cerro Hudson volcano was not recognized until its first 20th-century eruption in 1971. Cerro Hudson is the southernmost volcano in the Chilean Andes related to subduction of the Nazca plate beneath the South American plate. The massive, 1905-m-high Cerro Hudson covers an area of 300 sq km. The compound caldera is drained through a breach on its NW rim, which has been the source of mudflows down the Río de Los Huemeles. Two cinder cones occur north of the volcano and others occupy the SW and SE flanks. Hudson has been the source of several major Holocene explosive eruptions. An eruption about 6700 years ago was one of the largest known in the southern Andes during the Holocene; another eruption about 3600 years ago also produced more than 10 cu km of tephra. An eruption in 1991 was Chile's second largest of the 20th century and formed a new 800-m-wide crater in the SW part of the caldera.(GVN/GVP)

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JAPAN - Aso volcano

June 10th, 2011

Based on notices from JMA, the Tokyo VAAC reported that during 7-9 June plumes from Aso rose to altitudes of 1.5-1.8 km (5,000-6,000 ft) a.s.l. and drifted NW, N, NE, and E. Based on notices from JMA, the Tokyo VAAC reported that during 1-7 June plumes from Aso rose to altitudes of 1.5-2.1 km (5,000-7,000 ft) a.s.l. and drifted NW, N, NE, E, and S. Based on notices from JMA, the Tokyo VAAC reported that during 25, 27-28, and 31 May ash plumes from Aso rose to altitudes of 1.5-1.8 km (5,000-6,000 ft) a.s.l. and drifted NW, N, E, and S. Based on notices from JMA, the Tokyo VAAC reported that during 18-22 May ash plumes from Aso rose to altitudes of 1.5-2.1 km (5,000-7,000 ft) a.s.l. and drifted N, NE, and SE. A pilot noted on 18 May that an ash plume rose to an altitude of 3 km (10,000 ft) a.s. The Meteorological Agency on Monday raised the volcanic alert level for Mount Aso from 1 to 2, prompting local authorities in Kumamoto Prefecture to ban entry to areas within 1 km of the crater of Mount Naka, one of five peaks in the active volcano's central cone group. The alert includes a warning for rocks ejected from Mount Naka in the off-limits areas. The move came after the mountain belched a small amount of volcanic ash Friday and experienced a small eruption Sunday. On Monday, a small eruption and a 500-meter-high column of volcanic smoke were observed at around 10 a.m. The 24-km-wide Aso caldera was formed during four major explosive eruptions from 300,000 to 90,000 years ago. These produced voluminous pyroclastic flows that covered much of Kyushu. The last of these, the Aso-4 eruption, produced more than 600 cu km of airfall tephra and pyroclastic-flow deposits. A group of 17 central cones was constructed in the middle of the caldera, one of which, Naka-dake, is one of Japan's most active volcanoes. It was the location of Japan's first documented historical eruption in 553 AD. The Naka-dake complex has remained active throughout the Holocene. Several other cones have been active during the Holocene, including the Kometsuka scoria cone as recently as about 210 AD. Historical eruptions have largely consisted of basaltic to basaltic-andesite ash emission with periodic strombolian and phreatomagmatic activity. The summit crater of Naka-dake is accessible by toll road and cable car, and is one of Kyushu's most popular tourist destinations.(GVN/GVP)

JAPAN - Suwanose-Jima volcano (Ryukyu Islands)

January 14th, 2012

Based on information from JMA, the Tokyo VAAC reported an explosion from Suwanose-jima on 12 January. Details of a possible resulting plume were not reported. Based on a pilot observation, the Tokyo VAAC reported that on 14 October an ash plume from Suwanose-jima rose to an altitude of 1.2 km (4,000 ft) a.s.l. and drifted SE. Ash was not detected in satellite imagery.Based on information from JMA, the Tokyo VAAC reported an explosion from Suwanose-jima on 12 September. That same day an eruption produced a plume that rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted W.Based on a pilot observation, the Tokyo VAAC reported that on 14 July an ash plume from Suwanose-jima rose to an altitude of 3.7 km (12,000 ft) a.s.l. Ash was not detected in satellite imagery. Based on information from JMA, the Tokyo VAAC reported explosions from Suwanose-jima on 3 May. Details of a possible resulting plume were not reported. Based on information from JMA, the Tokyo VAAC reported that explosions from Suwanose-jima on 12 April produced a plume that rose to an altitude of 1.8 km (6,000 ft) a.s.l. Based on information from JMA, the Tokyo VAAC reported explosions from Suwanose-jima during 19-20 March. Details of a possible resulting plume were not reported. Based on information from JMA, the Tokyo VAAC reported an explosion from Suwanose-jima on 15 March. Details of a possible resulting plume were not reported Based on information from JMA, the Tokyo VAAC reported an explosion from Suwanose-jima on 3 March. Details of a possible resulting plume were not reported. Based on information from JMA, the Tokyo VAAC reported an explosion from Suwanose-jima on 9 and 14 February. Details of a possible resulting plume were not reported. Suwanose-Jima, one of Japan's most frequently active volcanoes, was in a state of intermittent Strombolian activity from On-take, the NE summit crater, that began in 1949 and lasted nearly a half century. The largest historical eruption took place in 1813-14, when thick scoria deposits blanketed residential areas, after which the island was uninhabited for about 70 years. The SW crater produced lava flows that reached the western coast in 1813, and lava flows reached the eastern coast of the island in 1884.

JAPAN - Sakurajima volcano

February 2nd, 2012

Based on information from JMA, the Tokyo VAAC reported that during 25-27 and 29-30 January explosions from Sakura-jima produced plumes that rose to altitudes of 1.5-3 km (5,000-10,000 ft) a.s.l. and drifted E and SE. On 29 January a pilot observed an ash plume that rose to an altitude of 2.1 km (7,000 ft) a.s.l.
Based on information from JMA, the Tokyo VAAC reported that during 18-24 January explosions from Sakura-jima produced plumes that rose to altitudes of 1.5-2.7 km (5,000-9,000 ft) a.s.l. and drifted N, NE, E, and SE. On 20 January a pilot observed an ash plume that rose to an altitude of 1.8 km (6,000 ft) a.s.l. Based on information from JMA, the Tokyo VAAC reported that during 11-17 January explosions from Sakura-jima produced plumes that rose to altitudes of 1.2-2.4 km (4,000-8,000 ft) a.s.l. and drifted NE, E, and SE. On 14 January a pilot observed an ash plume that rose to an altitude of 2.4 km (8,000 ft) a.s.l. and drifted S.
Based on information from JMA, the Tokyo VAAC reported that during 4-10 January explosions from Sakura-jima produced plumes that rose to altitudes of 1.5-2.7 km (5,000-9,000 ft) a.s.l. and drifted NE, E, SE, and S. On 7 January an ash plume rose to an altitude 2.7 km (9,000 ft) a.s.l. and drifted SE, then later dissipated.
Based on information from JMA, the Tokyo VAAC reported that during 28 and 30 December-3 January explosions from Sakura-jima produced plumes that rose to altitudes of 1.5-2.7 km (5,000-9,000 ft) a.s.l. and drifted NE, E, SE, and S. Based on information from JMA, the Tokyo VAAC reported that during 21-27 December explosions from Sakura-jima produced plumes that rose to altitudes of 1.5-2.7 km (5,000-9,000 ft) a.s.l. and drifted E, SE, S, and NE. Satellite imagery on 23 December showed ash emissions that later dissipated. On 27 December observations from satellite images and a pilot report showed an ash plume that rose to an altitude of 3.7 km (12,000 ft) a.s.l. and drifted 9 km E. Based on information from JMA, the Tokyo VAAC reported that during 14-20 December explosions from Sakura-jima produced plumes that rose to altitudes of 1.2-2.4 km (4,000-8,000 ft) a.s.l. and drifted SE and S. On 15 December satellite imagery showed ash emissions that later dissipated. A pilot reported that an ash plume rose to an altitude of 1.5 km (5,000 ft) and drifted 32 km S on 18 December.Based on information from JMA, the Tokyo VAAC reported that during 7-13 December explosions from Sakura-jima produced plumes that rose to altitudes of 1.0-2.7 km (3,000-9,000 ft) a.s.l. and drifted E, SE, S, and NE. Satellite imagery and a pilot report showed ash plumes that rose to an altitude of 2.4 km (8,000 ft) a.s.l and drifted 46 km SW on 9 December and 37 km S on 13 December.Based on information from JMA, the Tokyo VAAC reported that during 30 November and 2-6 December explosions from Sakura-jima produced plumes that rose to altitudes of 1.2-3.0 km (4,000-10,000 ft) a.s.l. and drifted NE, E, SE, W, NW. Satellite imagery and a pilot reports on 30 November and 5 December indicated ash plumes to an altitude of 3.7 km (12,000 ft) a.s.l that drifted 37 km SE and 74 km S, respectively. Sakura-Jima, one of Japan's most active volcanoes, is a post-caldera cone of the Aira caldera at the northern half of Kagoshima Bay. Eruption of the voluminous pyroclastic flow was associated with the formation of the 17 x 23-km-wide Aira caldera about 22,000 years ago. The construction of Sakura-Jima began about 13,000 years ago and built an island that was finally joined to the Osumi Peninsula during the major explosive and effusive eruption of 1914. Activity at the Kita-dake summit cone ended about 4,850 years ago, after which eruptions took place at Minami-dake. Frequent historical eruptions, recorded since the 8th century, have deposited ash on Kagoshima, one of Kyushu's largest cities, located across Kagoshima Bay only 8 km from the summit. The largest historical eruption took place during 1471-76. Sakurajima webcam

JAPAN - Kirishima group - Shinmoe-dake volcano

September 7th, 2011

Based on notifications from JMA, the Tokyo VAAC reported that during 31 August-6 September ash plumes from Kirishima's Shinmoe-dake (Shinmoe peak) rose to altitudes of 1.5-2.1 km (5,000-7,000 ft) a.s.l.
and drifted N, S, and SW. Based on notifications from JMA, the Tokyo VAAC reported an eruption from Kirishima on 6 August 2011. Based on notifications from JMA, the Tokyo VAAC reported that on 23 June an eruption from Kirishima's Shinmoe-dake (Shinmoe peak) produced a plume that rose to an altitude of 1.8 km (6,000 ft) a.s.l. and drifted E. According to Tokyo VAAC an explosion occured yesterday evening 18th of April from the active crater. An ash plume rose to about 3500 m high and some ashfalls were noted toward the North flank. Based on notifications from JMA and pilot observations, the Tokyo VAAC reported that during 3-4 April ash plumes from Kirishima's Shinmoe-dake (Shinmoe peak) rose to altitudes of 4.6-6.1 km (15,000-20,000 ft) a.s.l. and drifted E. Based on notifications from JMA, the Tokyo VAAC reported that an eruption from Kirishima's Shinmoe-dake (Shinmoe peak) on 23 March produced a plume that rose to an altitude of 2.4 km (8,000 ft) a.s.l. and drifted SE. Subsequent notices that day stated that the ash had dissipated. An eruption on 29 March produced a plume that rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted SE. As of the 13th of March, JMA and VAAC reported that a new explosive activity occured in the morning at 8:45 TU. the eruptive plume rose to vertically about 4000 m high and then drifted by the wind. There had not been any major activity at the site since March 1. Authorities have maintained a volcano warning at a level of three out of five, restricting access to the entire mountain. Based on reports from JMA, the Tokyo VAAC reported that plumes rose to altitudes of 1.5-3 km (5,000-10,000 ft) a.s.l. and drifted SE during 3-4 and 8 March. As of the 2nd of March, JMA reported that Shinmoe Peak erupted Tuesday 1st of March for the first time in around 10 days and 13th overall since Jan. 19, when the latest series of eruptions began.There were no reports of damage or injury from the 7:23 p.m. eruption, according to municipalities adjacent to the volcano, including the city of Miyakonojo and the town of Takaharu, both in Miyazaki Prefecture. Shinmoe Peak's activity has prompted local officials to prepare for the evacuation of residents several times. Tuesday's eruption was its first since Feb. 18. In the previous 17th of February update, the lava dome does not appear to have grown appreciably over the last week, suggesting the magma input rates under Shinmoe-dake have slowed considerably. The Japan Meteorological Agency expected rainfall of more than 4 mm per hour to last until Thursday night, an amount that could cause mudslides. The official, in the city of Miyakonojo, reported that 63 people had moved to evacuation centers by midday. On 11 and 14 February, pilots observed ash plumes that rose to altitudes of 4.6-6.1 km (15,000-20,000 ft) a.s.l. According to a news article, rocks ejected during an eruption on 14 February broke windows in cars parked at the Kirishima service area on the Miyazaki expressway and in several places in Kobayashi, 13 km NE. The Shinmoe Peak erupted again Friday after a seven-day hiatus, marking its 10th eruption since late January. The latest eruption occurred at 11:36 a.m. at the 1,421-meter-high volcano in the Kirishima range, spewing columns of smoke up to about 2,500 meters. The previous eruption was observed on Feb. 3. The Kagoshima Local Meteorological Observatory measured 244.3 pascals of air pressure disturbance at an observatory point some 3 kilometers southwest of the volcanic crater, adding it observed some relatively large volcanic stones falling. Based on reports from JMA, analyses of satellite imagery, and pilot observations, the Tokyo VAAC reported that during 2-8 February ash plumes rose to altitudes of 1.5-4.6 km (5,000-15,000 ft) a.s.l. and drifted SE. On 3 February, a pilot noted that an ash plume rose to an altitude of 9.1 km (30,000 ft) a.s.l. and drifted NE. According to JMA, scientists observed Shinmoe-dake during an overflight on 6 February and noted that the lava dome was about 600 m in diameter, similar to observations from four days prior. Gas plumes rose from the edges of the lava dome, from multiple areas on the E side of the dome, and from a central vent. Ash plumes rose 1.5 km above the crater rim and drifted SE. As of the 5th of February, the volcano is still erupting. According to local scientists, will continue its explosive eruptions over the next couple of weeks.According to the Geospatial Information Authority of Japan, the lava in the crater is believed to measure some 600 meters in diameter and stands up to around 110 meters high. Update 3rd of February : the volcano has been erupting more often since the morning of Feb. 1. While volcanic activity shows no signs of settling down, the crustal movements in the area have slowed since Jan. 31.Following the first major eruption on Jan. 26, the second and the third eruptions occurred at one to three-day intervals. After the fourth eruption shortly before 8 a.m. on Feb. 1, however, a total of five eruptions, including the latest at around 8 a.m. on Feb. 3, occurred at shorter intervals of five to 15 hours. The volcano's bowl-shaped crater, about 700 meters wide and 200 meters deep, is still covered by the lava dome. According to a Geospatial Information Authority of Japan announcement on Feb. 2, the highest point of the round-shaped lava dome has reached about 110 meters above the crater rim, with a difference of 5 meters from the lowest point. As of the 2nd of February, the volcano erupted for the second time Wednesday morning, marking the seventh eruption since last week. The latest eruption occurred at 10:47 a.m., coming on the heels of another one at 5:25 a.m. that spewed columns of smoke up an estimated 2,000 meters. So far no avalanche of volcanic debris from the crater has been observed and no injuries have been reported in the two prefectures. The sixth and seventh eruptions registered 299 pascals and 86 pascals, respectably, on an infrasonic meter installed 3 kilometers southwest of the crater and turned out to be much more moderate than Tuesday's fourth eruption that measured 458 pascals and shattered windowpanes in the surrounding area. As of the 1st of February, the volcano erupted violently at 7:54 a.m. on Feb. 1, causing windows of an inn and hospital in the Kagoshima Prefecture city of Kirishima to shatter. Meteorological officials with measuring equipment in Kirishima recorded a pressure of 458 pascals from the eruption. No pyroclastic flow, or current of hot gas, was seen in the eruption, which reportedly sent plumes of smoke 2,000 meters into the air. The top of a lava dome that had formed in the crater had apparently been blown apart by the eruption. There have been four explosive eruptions of the volcano since volcanic activity started intensifying on Jan. 26. The latest eruption produced a comparatively large amount of smoke, and a large amount of volcanic ash was expected to fall on the city of Miyakonojo in Miyazaki Prefecture. Geospatial Information Authority in Japan had noted inflation at Kirishima since December 2009 - and since May 10, they calculated ~6 million m 3 (0.006 km 3 ) of magma in a reservoir at 6 km depth that is ~10 km WNW from Shinmoe-dake and another 1 million m 3 (0.001 km 3 ) of magma at 3 km depth under the Shinmoe-dake cone itself. As of the 31st of January small eruptions have continued since ash and rocks were spewed in the first major volcanic eruption in 189 years last week, disrupting traffic and local residents' lives. According to the Kagoshima observatory, satellite images of the volcano show that the lava dome, which was 100 meters in diameter on Thursday, grew to about 500 meters in diameter on Saturday. T he Japan Meteorological Agency revised its exclusion order for the volcano, warning of large volcanic stones falling in areas within a 3-kilometer radius from the volcano's crater. Previously, it had warned people to stay away from areas with a 2-km radius. As of the 29th of January, ERI reported that following an overfligh above the volcano a lava dome has formed within the main crater of the Shinmoedake volcano. The lava dome is some tens of meters in diameter and parts of it are glowing red hot. A lake that had occupied the bottom of the crater before the eruption has vanished. Sources at the Kagoshima Local Meteorological Observatory say that at present it is unlikely the magma will overflow the crater, which measures 700-800 meters in diameter and a few hundred meters deep. However, according to the University of Tokyo researchers, "if the supply of magma continues to flow, it could leak out of the crater." Furthermore, in the southwest corner of the crater, traces of a 500-600 meter long pyroclastic flow were also found. As of the 28th of January, JMA reported that the eruptive activity was continuing. A second eruption occurred today 28th of January at about 1 p.m. local time. Ash from the volcano reached Miyazaki city, 50 kilometers (30 miles) to the east. The JMA is characterizing this as a small eruption for the moment  and the current alert status prevents people from going within 2 km of the volcano.No evacuations have been issued due to this eruption (although some people left on their own). Most of the problems caused by the eruption have been disruptions to air, train and road traffic in and around the area around Kirishima on Kyushu. As of the 27th of January, the Japanese Meteorological Agency (JMA) reported that the volcano began erupting around 7:30 Wednesday morning. Eruption started from Shinmoe-dake (Shinmoe peak), a stratovolcano of the Kirishima volcano group, on 19 January produced a shock wave that was detected 12 km NE and an ash plume that drifted SE Heavy clouds of smoke spewing from the Shinmoedake volcano on Mount Kirishima prompted the Japan Meteorological Agency to raise the volcanic alert level to a 3, warning people to clear the area within a mile of the volcano.By 3 p.m., heavy smoke could be seen billowing nearly 1500 m above the crater. According to preliminary report this activity looks to be phreatomagmatic explosions throwing material from the crater and/or pyroclastic flows and reports also indicatebombs being thrown upward of 2km.) from the vent. some plumes of incandescent material reaching a few hundred meters, producing the larger ash plume that caused the VAAC warning. Based on local news reports,ash has fallen on Nichinan and Myiakaki and parts of the Highways on Kyushu have been blocked due to the current activity. video about the eruption - another video - JMA webcams (in japanese) - Kirishima is a large group of more than 20 Quaternary volcanoes located north of Kagoshima Bay. The late-Pleistocene to Holocene dominantly andesitic volcano group consists of stratovolcanoes, pyroclastic cones, maars, and underlying shield volcanoes located over an area of 20 x 30 km. The larger stratovolcanoes are scattered throughout the field, with the centrally located, 1700-m-high Karakuni-dake being the highest. Onami-ike and Mi-ike, the two largest maars, are located SW of Karakuni-dake and at its far eastern end, respectively. Holocene eruptions have been concentrated along an E-W line of vents from Mi-ike to Ohachi, and at Shinmoe-dake to the NE. Frequent small-to-moderate explosive eruptions have been recorded since the 8th century.

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USA - Kilauea volcano ( Hawaian islands)

February 3rd, 2012

During 25-31 January, HVO reported that the lava lake circulated and periodically rose and fell in the deep pit within Kilauea's Halema'uma'u Crater. Almost daily measurements indicated that the gas plume from the
vent continued to deposit variable amounts of ash and fresh spatter nearby. During 25-27 January lava ejections on the SE edge built a small spatter rampart and produced small lava flows on the inner ledge. Incandescence was visible on the NE, SE, and W edges of the Pu'u 'O'o crater floor during 25-31 January. On 25 January lava started to fill a Pu'u 'O'o crater floor depression and continued episodically all week.
Geologists on a 26 January overflight reported lava flows 4 km SE of Pu'u 'O'o. On 27 January the SE and NE vents started to effuse lava. During 24-31 January, thermal anomalies were seen in satellite imagery 3-4 km SE
of Pu'u 'O'o cone. Overall eruptive activity was slightly elevated. DI deflation started and the summit lava lake started to drop. Within Pu`u `O`o Crater, the eastern depression was periodically covered with lava. Surface flows were active southeast of Pu`u `O`o. Overall seismic tremor levels were low and gas emissions were elevated.During 18-24 January, HVO reported that the lava lake circulated and periodically rose and fell in the deep pit within Kilauea's Halema'uma'u Crater, remaining below the inner ledge (75 m below the crater floor). Almost daily measurements indicated that the gas plume from the vent continued to deposit variable amounts of ash and fresh spatter nearby As of the 20th of January, HVO reported that overall eruptive activity was low with continuing tilt and lava lake level oscillations. DI deflation may have started this morning but the summit lava lake level remained stable and had not yet started to drop. Within Pu`u `O`o Crater, glow could be seen from several sources with a brief lava flow across the crater floor around 3 am this morning. Overall seismic tremor levels were low and gas emissions were elevated. During 11-17 January, HVO reported that the lava lake circulated and periodically rose and fell in the deep pit within Kilauea's Halema'uma'u Crater, remaining below the inner ledge (75 m below the crater floor). Almost daily measurements indicated that the gas plume from the vent continued to deposit variable amounts of ash and fresh spatter nearby. As of 13th of January, HVO reported that overall eruptive activity was low. DI deflation slowed and the summit lava lake dropped. Surface flows were active a short distance southeast of Pu`u `O`o cone; glow and short flows could be seen from sources within Pu`u `O`o crater via webcam. Overall seismic tremor levels were low and gas emissions were elevated. During 4-10 January, HVO reported that the lava lake circulated and periodically rose and fell in the deep pit within Kilauea's Halema'uma'u Crater, remaining below the inner ledge (75 m below the crater floor). Almost daily measurements indicated that the gas plume from the vent continued to deposit variable amounts of ash and fresh spatter nearby. During 28 December-3 January, HVO reported that the lava lake circulated and periodically rose and fell in the deep pit within Kilauea's Halema'uma'u Crater, remaining below the inner ledge (75 m below the crater floor). Almost daily measurements indicated that the gas plume from the vent continued to deposit variable amounts of ash and fresh spatter nearby. Incandescence was visible from small spatter cones on the E and S edges of the Pu'u 'O'o crater floor and along the 21 September 2011 fissure on the SE flank of the Pu'u 'O'o cone. Geologists on an overflight reported that pahoehoe lava flows were significantly broader (700-1,000 m) across the coastal plain and were entering the ocean along a 900 m wide area of the coast on 27 December. Lava flows continued to be active about 6.8 km SE of Pu'u 'O'o and entered the ocean W of Ka'ili'ili on 28 December. During 29 December-2 January a web camera showed no surface activity on the pali, weak sporadic flows near the coast, and weak plumes from the ocean entry. At night during 31 December-2 January incandescence was seen above the pali; on the night of 1 January ground based observers reported lava on the pali. Clouds prevented observations from a web camera on 3 January.During 14-20 December, HVO reported that the lava lake circulated and periodically rose and fell in the deep pit within Kilauea's Halema'uma'u Crater, remaining below the inner ledge (75 m below the crater floor). Almost daily measurements indicated that the gas plume from the vent continued to deposit variable amounts of ash and fresh spatter nearby. Incandescence was visible along the 21 September fissure on the SE flank of Pu'u 'O'o cone, from a skylight on the lava tube, and from small spatter cones on the E and S edges of the Pu'u 'O'o crater floor. Pahoehoe flows that were 300-400 m wide, fed by lava tubes from the fissure, continued to be active about 6.8 km SE of Pu'u 'O'o and entered the ocean W of Ka'ili'ili. The lava delta now extends 15-20 m into the ocean at a point 6.4 km W of the Chain of Craters Road. During 17-20 December the lava flow branched, with lobes advancing NE and W into the ocean. Infrequent plumes were observed from the ocean entry during 18-20 December. During the past 24h, the West Ka`ili`ili ocean entry continued to be weakly active fed by flows from Pu`u `O`o through the abandoned Royal Gardens subdivision and across the coastal plain. Glow could be seen from a source within Pu`u `O`o crater. Summit lava lake levels were stable, seismic tremor levels were low, and gas emissions were elevated. As of the 16th of december, HVO reported that The West Ka`ili`ili ocean entry continued to be active and fed by flows from Pu`u `O`o through the abandoned Royal Gardens subdivision and across the coastal plain. Glow and spatter could be seen from sources within Pu`u `O`o crater. Summit and Pu`u `O`o tilt recorded a full DI event and the summit lava level dropped and rose accordingly. Seismic tremor levels were low and gas emissions were elevated. During 7-13 December, HVO reported that the lava lake circulated and periodically rose and fell in the deep pit within Kilauea's Halema'uma'u Crater, remaining below the inner ledge (75 m below the crater floor). Almost daily measurements indicated that the gas plume from the vent continued to deposit variable amounts of ash and fresh spatter nearby. Incandescence was visible along the E and W edges of the Pu'u 'O'o crater floor, along the 21 September fissure on the SE flank of Pu'u 'O'o cone, and from a skylight on the lava tube. Lava continues to erupt into the perched pond formed on 6 December. Pahoehoe flows, fed through lava tubes from the fissure, continued to be active about 6.8 km SE of Pu'u 'O'o based on intermittent views from satellite. Analysis of 10-12 December satellite images suggested that lava had reached the coast and was flowing into the ocean. During 11-12 December incandescence was observed from small spatter cones on the E and S edges of the Pu'u 'O'o crater floor; short lava flows issued from the E edge of the crater floor on 12 December. As of the 9th of December, HVO reported that lava continues to flow into the tube system that descends the northeast flank of the Pu`u `O`o cone and feeds flows down the pali through the abandoned Royal Gardens subdivision and the coastal plain. Eruption of lava in the eastern pond was intermittent. Tilt at Pu`u` `O`o is generally following the DI pattern at the summit, but more subdued with many small fluctuations. Tilt at the summit leveled off late last night, recording deflation at 3:13 am and slow inflation starting at about 5:08 am. The lava lake level remained steady in the past 24 hours. Seismic tremor levels were low and gas emissions were elevated. During 4-5 December the vent on the E edge of the crater produced lava flows that partially filled the depression left by the flank fissure eruption in September and a perched lava lake was built on 6 December. As of the 2nd of December, HVO reported that Back-to-back DI events continued with the most recent DI deflation yesterday followed by a small drop in the summit lava lake. At Pu`u `O`o, incandescence was visible from several sources on the crater floor as was glow from the fissure and skylight on the southeast flank and a new source low on the north flank. Lava flows were active southeast of Pu`u `O`o within the abandoned Royal Gardens subdivision. Seismic tremor levels were low and gas emissions were elevated. During 23-29 November, HVO reported that the lava lake circulated and periodically rose and fell in the deep pit within Kilauea's Halema'uma'u Crater, remaining below the inner ledge (75 m below the crater floor). Almost daily measurements indicated that the gas plume from the vent continued to deposit variable amounts of ash and fresh spatter nearby. Incandescence was visible from the E and W edges of the Pu'u 'O'o crater floor, and from the 21 September fissure on the SE flank of Pu'u 'O'o cone. Pahoehoe flows, fed through lava tubes from the fissure, continued to be active about 5.7 km SE of Pu'u 'O'o based on intermittent views from satellite. Incandescence from a skylight on the lava tube was also observed. As of the 25th of November, HVO reported that Back-to-back DI events continued with the most recent DI inflation at 8 pm last night and the summit lava lake rose with tilt. At Pu`u `O`o, incandescence was visible from sources on the crater floor and on the southeast flank. Lava flows were presumed active southeast of Pu`u `O`o although no satellite images were available. Seismic tremor levels were low and gas emissions were elevated. The Webcam images, which are updated every five minutes, can be accessed at : http://volcanoes.usgs.gov/hvo/cams/NCcam/ . From HVO - Near real-time web cam Pu'u'O'o. Halemaumau webcam

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U.S.A. - Mauna Loa ( Hawaii)

January 12th, 2010

As of the 11th of January, the Hawaiian Volcano Observatory (HVO) has reported there has been no recent significant change in line length across the summit or the flanks of Mauna Loa as measured by GPS receivers on opposite sides of the volcano. Tiltmeters have recorded no significant changes other than abrupt offsets that are related to instrumental issues, severe weather, or significant earthquakes. Sensors within a fissure in Moku`aweoweo crater floor reported gas concentrations within normal values; fumarole temperatures continued to slowly decrease. Line lengths have been increasing at a slightly faster rate since September, 2008,due mostly to slippage on basalt faults beneath Mauna Loa's east flank and not to an increase in magma supply to the volcano. Tiltmeters have recorded no significant changes other than abrupt offsets that are related to instrumental issues. Diurnal tilt, or the tilting due to daily heating and cooling of the ground, was diminished by snowfall starting Christmas Eve, 2008. Sensors within a crack in Moku`aweoweo crater floor continued to record background gas concentrations and temperatures. Since the beginning of January, 2005, HVO analysts have rarely located more than 10 earthquakes per week beneath Mauna Loa summit. Each week, 1-5 earthquakes are also located beneath the Kealakekua area of west Mauna Loa. These levels are typical of the past several years. The Kao`iki seismic zone between Mauna Loa and Kilauea volcano summits remained active with an average of about 10-40 earthquakes per week; these numbers may reflect increased seismic activity nearer Kilauea summit rather than increased Kao`iki activity.

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USA - Cleveland volcano (Alaska)

February 1st, 2012

AVO reported that on 31 January the Volcano Alert Level for Cleveland was raised to Watch and the Aviation Color Code was raised to Orange due to the formation of a new 40-m-wide lava dome in the summit crater that was observed in satellite imagery on 30 January. The lava dome that formed during the past fall and winter was removed by explosive activity on 25 and 29 December 2011. No current seismic information was available because Cleveland does not have a real-time seismic network. AVO reported that during 19-23 October cloud cover over Cleveland prevented views of the lava dome in the summit crater. The Volcano Alert Level remained at Watch and the Aviation Color Code remained at Orange. No current seismic information was available because Cleveland does not have a real-time seismic network. AVO reported that during 5-6 and 9-11 October cloud cover over Cleveland prevented views of the lava dome in the summit crater. Partly cloudy satellite views during 7-8 October showed elevated surface temperatures at the summit. The Volcano Alert Level remained at Watch and the Aviation Color Code remained at Orange. No current seismic information was available because Cleveland does not have a real-time seismic network. The size of the lava dome is now about 165 m (540 ft) in diameter compared to 150 m (490 ft) in diameter on September 9,2011. The growing lava dome remains entirely contained within the summit crater but is now approximately 20 meters below the eastern rim. Analysis of TerraSAR-X satellite radar images through September 9 indicate that the dome now occupies the entire crater floor (about 150 by 150 m across), but is still lower than the crater rim. Thermal anomalies were observed in satellite data during periods of clear weather this past week and were consistent with continued eruption of lava. No ash emissions have been observed during this eruption, which began in mid-July, 2011. The latest episode of dome growth resumed around September 3. A growing lava dome in the crater increases the possibility of an explosive eruption, but does not necessarily indicate that one will occur. Short-lived explosions could produce ash clouds that exceed 20,000 ft above sea level. These events can occur without warning and may go undetected in satellite imagery for hours. If lava dome growth continues, it could overflow the crater rim to produce a lava flow and/or collapse to produce pyroclastic flows. Collapse of a lava flow or dome would likely result in the generation of a volcanic ash cloud. A thermal anomaly at the summit was observed during 3-5 September. Observations on 6 September indicated that the lava dome had resumed growth, reaching 120 m in diameter and filling the floor of the crater. AVO raised the Volcano Alert Level to Watch and the Aviation Color Code to Orange Clouds have obscured the summit of Mt. Cleveland over the past 24 hours and AVO has received no new information about unrest at the volcano. Because of the extensive cloud cover, we do not know if the M6.8 Fox Islands earthquake that occurred at 2:55 AM AKDT, September 2 had any effect on the unrest at Mt. Cleveland. Earlier this week, AVO lowered the Aviation Color Code/Volcano Alert Level to Yellow/Advisory based on satellite data indicating no significant change in the size of the lava dome in the summit crater. Although the dome-producing eruption at Mt. Cleveland appears to have stopped or paused, it remains possible for dome growth to resume at any time. If growth of the lava dome does resume, it is possible, but not certain, that explosive ash-producing activity may follow. AVO reported that during 17-23 August cloud cover over Cleveland prevented observations of the summit crater. On 21 August AVO noted that a weak, 1-pixel thermal anomaly was observed in a recent satellite view during a cloud break. The Volcano Alert Level remained at Watch and the Aviation Color Code remained at Orange. No current seismic information was available because Cleveland does not have a real-time seismic network. As of the 9th of August AVO reported that thermal anomaly at the summit of Cleveland volcano observed overnight in several satellite images. Effusive eruption of lava dome in summit crater possibly continuing. AVO has received no additional information or observations about unrest at the volcano. Without a real-time seismic network on the volcano, AVO is unable to track local earthquake activity related to volcanic unrest, provide forecasts of eruptive activity, or confirmation of explosive, ash-producing events. AVO is monitoring the volcano using satellite data as it becomes available. AVO reported that on Wednesday, July 20,2011 AVO raised the aviation color code/volcano alert level for Cleveland volcano to Yellow/Advisory following the detection of persistent thermal anomalies in satellite data. A thermal anomaly was detected in satellite images this morning. No other activity has been observed at the volcano. Without a real-time seismic network at Cleveland, AVO is unable to track local earthquake activity related to volcanic unrest. Short-lived explosions with ash clouds that could exceed 20,000 ft above sea level can occur without warning and may go undetected on satellite imagery for hours. Low-level ash emissions at Cleveland occur frequently and do not necessarily mean a larger eruption is imminent. AVO continues to monitor the volcano using satellite imagery.The Volcano Alert Level remained at Advisory and the Aviation Colour Code remained at Yellow. The 1730-m-high Mt. Cleveland is the highest of the Islands of the Four Mountains group and is one of the most active of the Aleutian Islands. The native name for Mt. Cleveland, Chuginadak, refers to the Aleut goddess of fire, who was thought to reside on the volcano. Numerous large lava flows descend the steep-sided flanks of the volcano. It is possible that some 18th-to-19th century eruptions attributed to Carlisle should be ascribed to Cleveland (Miller et al., 1998). In 1944 Cleveland produced the only known fatality from an Aleutian eruption. Recent eruptions from Mt. Cleveland have been characterized by short-lived explosive ash emissions, at times accompanied by lava fountaining and lava flows down the flanks.

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U.S.A. - Redoubt volcano (Alaska)

April 8th, 2010

As of the 7th of March, the shallow, small earthquakes at Redoubt Volcano continued at about the same rate as yesterday. Satellite images from yesterday evening show a steam plume extending from the summit. Webcam views of Redoubt continue to be obscured by clouds.As of the 5th of April, AVO raised the Aviation Color Code to YELLOW and the Volcano Alert Level to ADVISORY at Redoubt volcano this morning. A series of small repetitive earthquakes began at 01:44 AKDT (0944 UTC) this today in the vicinity of the volcano's summit. Activity is continuing this afternoon. These earthquakes may be precursory to renewed eruptive activity at the volcano and increased instability of the lava dome. Whether this will result in explosive activity or failure of the lava dome is unknown at this time. However, there is a heightened possibility of volcanic activity that would produce a volcanic ash cloud, pyroclastic avalanches, and lahars and flooding down the Drift River.As of the 6th of January, the Alaska Volcano Observatory (AVO) reported that seismic activity at Redoubt Volcano remains low. Web camera and satellite views of the volcano have been obscured by clouds and snow. There have been no reports or indications today of unusual activity at the volcano. The Aviation Colour Code remains YELLOW and the Volcano Alert Level remains ADVISORY. AVO is continuing to evaluate information to interpret this week's uptick in seismicity and gas output. One explanation involves input of new magma or remobilisation of existing magma within volcano's shallow plumbing system. This process appears to have ceased or paused. It remains possible that activity could reappear, intensify and lead to additional eruptive activity. We would expect a sharp increase in seismicity and other marked changes prior to such activity. AVO will continue to issue daily status reports as long as the Aviation Colour Code and Alert Level are elevated. As of the 28th of August 2009, AVO reported that the code status has been lowered for Aviation to Colour Code Green and Volcano Alert at Code Normal at 18:44 GMT on 29 September 2009. Over the past several months, seismic activity, volcanic gas output, ground deformation, lava dome temperatures, and outward signs of lava dome instability at Redoubt Volcano have been declining. The volcano appears to have returned to its normal background condition and for now poses no immediate threat of eruptive activity. Accordingly, AVO is lowering the Aviation Color Code to GREEN and the Volcano Alert Code to NORMAL. The AVO notes that the Redoubt lava dome has reached a volume of approximately 70 million cubic metres, and that lava domes on steep slopes are ‘typically unstable'. However, given that 60 days have passed since the dome ceased to grow, ‘AVO believes the possibility for dome collapse is small and declining toward a background level of danger typical of many active stratovolcanoes with steep unstable rock slopes'. Local hazards remain, associated with the hot lava dome: gas emission, abundant steaming, rockfalls, but these do not pose a significant hazard beyond the summit area of the volcano. On 12 June, the lava dome was an estimated 1 km long, 460 m wide, and 200 m high. The Volcanic Alert Level remained at Watch and the Aviation Color Code remained at Orange.On 28th of May. a M3.7 earthquake occured on the Alaska Peninsula at approximately 03:11 shows prominently on the Redoubt webicorder records. Again, this seismic event is not related to activity at Redoubt. AVO reported that during 20-26 May seismicity from Redoubt remained above background levels and growth of the lava dome in the summit crater continued. Steam-and-gas emissions from the lava dome were seen on the web camera during 20-21 and 26 May; clouds obscured the view during the rest of the reporting period. Occasional rockfalls originating from unstable slopes of the lava dome possibly produced minor ash clouds in the vicinity of the summit, although no ash was detected by satellite or radar. As of the 20th of May, AVO reported that during 13-19 May seismicity from Redoubt had decreased from levels detected during 2-7 May, but remained above background levels. Rock avalanche events, discrete earthquakes, and minor volcanic tremor were evident in seismic data. Growth of the lava dome in the summit crater continued and vigorous steam emissions from the margins of the lava dome were seen on the web camera. Occasional rockfalls originating from unstable slopes of the lava dome produced minor ash clouds in the vicinity of the summit. Occasional incandescence was observed in nightime images from the web camera. On 15 May, the volume of the dome was an estimated 30-60 million cubic meters. During an overflight on 16 May, scientists observed a turquoise lake along the S margin of the dome, and a hot, vigorous, and persistent fumarole on the W wall of the upper gorge. The Volcanic Alert Level remained at Watch and the Aviation Color Code remained at Orange. During 29 April-5 May, AVO reported that elevated seismicity from Redoubt and a persistent thermal anomaly over the summit lava dome detected on satellite imagery were consistent with continued lava-dome growth. Changes in the size and shape of the dome confirmed growth; the volume of the dome was an estimated 25-30 million cubic meters. Occasional small rock avalanches originating from the N side of the lava dome produced minor low-level ash emissions. As of the 3rd of May, the Alaska Volcano Observatory (AVO) reported that eruption of Redoubt volcano continued. seismic activity has increased in the last 24 hours. Minor emissions of ash have also been visible in webcam views during this time period. A vigorous steam plume, rising to altitudes up to 18,000' above sea level, has been visible in webcam images throughout the afternoon of 3rd of May. Currently, this plume contains small amounts of ash based on web camera views, satelite data, and a pilot report. Seismic activity has also increased in the past 24 hours. previous notable informations : ongoing lava dome growth kept seismicity at Redoubt remained elevated during 15-21 April, and vigorous steam-and-gas plumes (possibly with occasional small amounts of ash) rose to altitudes below 4.6 km a.s.l. Satellite imagery revealed thermal anomalies at the summit and drifting SO2 plumes. The lava dome size was estimated on 16 Aril to be 500 x 700 m across and at least 50 m thick. Seismic and satellite data over the past day indicate continued lava dome growth. The volcano was not visible in web camera views during the night. A low-level steam and gas plume that may contain small amounts of ash is likely present. Based on seismic data and satellite imagery, AVO reported that Redoubt's lava dome continued to grow during 8-14 April. As of the 10th of April, A small steam plume with possible traces of ash has been visible in satellite and partially-obscured webcam images today. The plume is currently extending to the northeast of the volcano at low altitudes. Additional significant explosive events with accompanying ash clouds, ash fall, and mudflows are possible and can occur with little or no warning. AVO will maintain 24/7 operations in order to quickly detect renewed significant explosive activity and other hazardous phenomena. Seismic and satellite data over the past day indicate continued lava dome growth. A satellite image from yesterday afternoon showed a continuous sulfur dioxide gas plume extending for more than 600 miles from volcano. As of the 3rd of April, AVO reported that the eruption continued, but the intensity of ash-production has decreased. The current alert level at Redoubt is WATCH and aviation color code is ORANGE. The small, shallow repeating volcanic earthquakes have diminished. A few occasional larger events are still being observed. These earthquakes are most prominent on station REF. As the 2nd of April, AVO reported that the volcano continues to emit a plume of gas, steam and variable amounts of ash to low elevations. Winds are blowing the plume E to ESE. Weak volcanic tremor is ongoing, punctuated by small, discrete earthquakes. As of the 30th of March (11:56AM - AKDT), AVO reported that Over the past twelve hours, ash emissions at Redoubt Volcano have become more frequent, but lower in altitude than during the highly explosive events of the past week. A continuous ash plume has been observed in web camera, satellite and radar images, and by pilots. These plumes vary in their intensity and have generally been at low altitude (less than 20,000 feet above sea level). Occasional, short lived events have produced ash clouds that rise as high as 27,000 feet above sea level. Ash fall from these events is currently not likely to reach population centers in the Cook Inlet. In the evening, Seismicity continued to show small, discrete events. Observers on an AVO gas flight reported ash falling from the plume 20-25 miles from the vent. Winds at that altitude are heading NE from the volcano. A regional earthquake south of Kodiak was visible on the webicorders at 19:28. As of the 27th of March, AVO reported that three more explosions occured on Friday. The first eruption at 17:35 AKDT (01:35 GMT) produced an eruption cloud to 40000 feet (12200 metres) above sea level; the second eruption at 19:25 AKDT (03:25 GMT) sent up a plume to 51000 feet (15500 metres); and the third, beginning at 23:20 AKDT (07:20 GMT), produced a cloud that has reached 40000 feet (12200 metres). Due to important ashfall the Hut webcam has been covered since 18:00 local time and no new images were available.. As of the 23rd of March, AVO reported that the last explosive event occurred during the night (March 23) at 7:41 pm (AKDT) and lasted for roughly seventeen minutes. The top of the ash cloud was estimated to have reached at least 50,000 ft above sea level based on National Weather Service radar. Winds in the vicinity of the volcano carried the ash cloud primarily to the west and north. Pyroclastic flows were visible traveling down the volcano's north flank in web camera images. Last night's explosive event was the sixth thus far since explosive activity began Sunday. The day before, AVO staff visited the area around Redoubt by helicopter to assess conditions and repair equipment damaged by Sunday night's eruptions. They fixed the telemetry link at AVO's observation hut, which is once again transmitting images from the web camera and data from a GPS and two seismic instruments. Clouds obscured the summit, but observers reported very large lahar and flood deposits in the Drift River Valley that likely occurred during and/or following the first five explosions. These flows, which contained ice, water, mud, and other debris, inundated the Drift River Valley and traveled more than 35 km, reaching Cook Inlet. In the middle to upper Drift River Valley, high-water marks reached 6-8 meters above the valley floor. At the AVO hut (roughly 7 miles NNW of the summit), a 6-cm thick fall deposit was observed.As of 2:00AM March 23, 2009, AVO has recorded FOUR large explosions at Redoubt volcano at the following times: March 22 10:38PM; March 22 11:02PM; March 23 12:14AM; March 23 01:39AM. On Sunday morning, 40 to 50 earthquakes were being recorded every hour. The largest eruption sending a plume of smoke some 50,000 feet above sea level The National Weather Service has issued an Ashfall. The first Mt. Redoubt began at approximately 22:38 AKDT, March 22, 2009 (0638 UTC). AVO was raising immediatly the aviation color code to Red and the alert level to Warning. Initial height of the eruption cloud is estimated at less than 20,000 ft above sea level at present. Previously, as of the 19th of March, AVO reported that Mount Redoubt was been going through some interesting seismic evolutions over the past 24 hours. From around 00:00 to around 08:00 GMT on 20 March (around 16:00-00:00 on 19 March, local time) there was a period of marked volcanic tremor. The amplitude of the tremor diminished subsequently, but a pattern of small discrete quakes (around 1-2 per hour) interspersed with occasional larger seismic events continued, with the smaller quakes increasing in frequency and amplitude from around 10:00 local time A special bulletin from AVO reported that seismic activity at Mount Redoubt increased at about 1:05 AKDT Sunday afternoon (March 15, 2009) and approximately 4 hours of continuous volcanic tremor ensued. The onset of the tremor was associated with a small explosion that produced a plume of gas and ash that rose to about 15,000 feet above sea level and deposited a trace amount of ash over the summit-crater floor and down the south flank of the volcano to about 3,000 feet. AVO responded to this increase in activity by raising the color code and alert level to ORANGE/WATCH at 2:50 PM AKDT. At this time it does not appear that the increase in activity heralds a significant eruption in the short term, but conditions may evolve rapidly. An AVO overflight Sunday witnessed activity from 11:30 AM until about 3:00 PM and was able to document ash emission from a new vent, just south of the 1990 lava dome and west of the prominent ice collapse feature near the north edge of the summit crater. Although ash emission was short lived, it represents the first documented ash fall during the current episode of unrest at Mount Redoubt. About twenty minutes after the initial steam and ash burst, a sediment-laden flow occurred from a small area in the ice at about 7000 feet on upper Drift glacier. This flow descended about 1500 feet and produced a distinctive seismic signature seen across the Redoubt network. On 25 February, a small mud flow originating from a melt hole in the Drift Glacier traveled several hundred meters. Satellite images revealed that the next day another mudflow traveled several kilometers and covered a large portion of the Drift Glacier. Web camera views and satellite imagery showed no unusual activity; steam plumes within the summit crater were seen on the web camera on 26 and 1 March. As of the 27th of February, the Alaska Volcano Observatory (AVO), reported that at unrest at Redoubt Volcano continues. Beginning yesterday afternoon at 1537 hrs AKST, tremor amplitude increased sharply and remained elevated for approximately one hour. At 1614 hrs AKST, the tremor amplitude briefly matched the highest amplitude seen during the current episode of unrest. This tremor was strong enough to be recorded on all seismic stations on Redoubt Volcano as well as many stations surrounding Cook Inlet. Since that time, tremor amplitude has decreased significantly. Last night around 2240 hrs AKST, the number of discrete earthquakes increased and remained elevated until about 0255 hrs AKST today. Preliminary analysis of these earthquakes indicate they are occurring at shallow depth (1 to 3 km) below the summit crater of Redoubt. Since that time, discrete events are continuing at a lower rate, and tremor levels remain low. These variations in the character of seismic activity indicate that conditions have changed at shallow depths beneath the volcano. AVO is currently analyzing this seismic activity and will issue further information as it becomes available. An observation flight to the volcano is currently underway. Winds are too high at the volcano to perform gas measurements today. A small steam plume is visible in clear Hut Cam images today. AVO continues to monitor Redoubt Volcano closely, and the observatory is staffed 24 hours a day. A burst of volcanic tremor occurred just after 3:00 PM in the afternoon 5th of February lasting for about 30 minutes and is continuing at a sustained but lower level. This did not result in any eruptive activity and no ash emission has occurred. Following bursts of volcanic tremor during the afternoon , background tremor has remained elevated relative to the past several days. AVO continues to monitor the volcano 24/7. As of the 1st of February AVO reported that unrest at Redoubt Volcano continues. Seismicity has remained relatively constant over the last 24 hours and is still well above background. A vapor plume is intermittently visible in the AVO web camera. It appears to rise no higher than the volcano's summit. An observation and gas-measurement flight to the volcano yesterday noted continued vigorous fumarolic activity and runoff of muddy water down the north flank of the volcano. Volcanic gas was detected; data analysis is ongoing to compare these measurements with previously measured gas output. As of the 30th of January, AVO reported that seismicity levels have increased since yesterday evening and have also risen markedly over the last hour. Pilot reports, clear AVO webcam views, and satellite and radar views confirm that Redoubt Volcano has not yet erupted at the time of this report. Redoubt remains at Aviation Color Code ORANGE and Volcano Alert Level WATCH. As of the 25th of January, AVO previously reported that over the past 48 hours, seismic activity at Redoubt Volcano has increased markedly. This has taken the form of periodic tremor bursts that are most visible on the two seismic stations closest to the summit. Beginning at 00:58 AKT (9:58 UTC) this morning, tremor became sustained and its amplitude increased markedly. AVO raised the Aviation Color Code to ORANGE and the Alert Level to WATCH in the morning at 2:09 AKT (11:09 UTC). This activity could be precursory to an eruption, perhaps within hours to days. A further increase in seismicity is expected to accompany an eruption. Information Statement Unrest at Redoubt Volcano continues. AVO conducted an overflight of the volcano in the afternoon of 25th of January, and observations confirmed that an eruption has not occurred yet. Increased steaming through previously observed sources in the snow and ice cover were seen and sulfur gas emissions were noted. There was no significant disruption of the glacial ice, nor any apparent increased water discharge down the Drift River. Seismicity began to decline at about 05:30 AST (14:30 UTC) on the morning, but remained elevated. AVO raised the Aviation Color Code to YELLOW and the Volcano Alert Level to ADVISORY on November 5, 2008, in response to increased emissions of SO2, H2S, and CO2; melting of snow and ice near the volcano's summit; and a subtle increase in seismicity. These observations reflected a change in the volcano's hydrothermal system, possibly associated with an influx of new magma beneath the volcano. It is also possible that the change was related to the development of a new pathway of heated fluids rising from magma intruded during the 1989-90 eruption. From Miller et al (1998): "Redoubt Volcano is a steep-sided cone about 10 km in diameter at its base and with a volume of 30-35 cubic kilometers. The volcano is composed of intercalated pyroclastic deposits and lava flows and rests on Mesozoic granitic rocks of the Alaska-Aleutian Range batholith (Till and others, 1993; 1994). It has been moderately dissected by the action of numerous alpine glaciers. A 1.8-km-wide, ice-filled summit crater is breached on the north side by a northward-flowing glacier, informally known as the Drift Glacier, which spreads into a piedmont lobe in the upper Drift River Valley. The most recently active vent is located on the north side of the crater at the head of the Drift glacier. Holocene lahar deposits in the Crescent River and Drift River valleys extend downstream as far as Cook Inlet." Live webcam


USA - Mount Cleveland volcano (Aleutian islands)

December 30th, 2011

Earlier today Friday, AVO lowered the aviation color code to YELLOW and alert level to ADVISORY for Cleveland Volcano. No new explosive activity has been observed at the volcano since the ash cloud that was detected yesterday morning. More sudden explosions producing ash or ejecting blocks may still occur with plumes exceeding 20,000 feet above sea level. Such explosions and their associated ash clouds may go undetected in satellite imagery for hours. However, in cooperation with the University of Washington, AVO has implemented a lightning alarm system that may detect significant ash-producing events within minutes of onset. If a large explosive event occurs, seismic signals may be recorded on AVO seismic networks at nearby volcanoes. There is no real-time seismic monitoring network at Cleveland. A detached drifting ash cloud to approximately 15,000 ft ASL has been detected at Cleveland Volcano in satellite images from 1402 UTC, Dec 29. As of 1445 UTC the ash cloud was approximately 80 KM/50 miles moving ESE from the volcano. Based on the presence of an ash cloud, AVO has raised the aviation color code at Cleveland Volcano to ORANGE and alert level WATCH. Satellite data indicate that this is a single explosion event, however, more sudden explosions producing ash could occur with plumes exceeding 20,000 feet above sea level. Clouds have obscured satellite views of Cleveland volcano throughout the past week, and AVO has not received additional reports of activity. Thus, it is not known if subsidence of the summit lava dome continues. The new lava dome began growing at Cleveland in late July 2011 and eventually reached about 10 m (33 feet) below the crater rim. Last observed dome growth occurred in early October, and recent views of the summit show gradual subsidence and disintegration of the summit dome. Throughout this period of unrest and eruption, AVO has not observed deposits or features indicative of explosions or ash emission. Cleveland's activity from late July to present can be characterized as an effusive lava eruption. The volume of the lava dome prior to deflation was about one million cubic meters (1.3 million cubic yards). AVO reported that a thermal anomaly over the lava dome surface in Cleveland's summit crater was visible on 2 November, although cloudy views mostly prevented observations. On 3 November AVO lowered the Volcano Alert Level to Advisory and the Aviation Color Code to Yellow because satellite observations indicated no significant change in the size of the lava dome, and no explosive activity or ash emissions had been reported. Cloud cover continued to prevent observations during 4-6 November. Satellite imagery showed slightly elevated temperatures near the volcano's summit during 6-7 November. No current seismic information was available because Cleveland does not have a real-time seismic network. AVO reported that although cloud cover often prevented observations of Cleveland during 7-12 September, a thermal anomaly on the lava dome was visible during 8-9 and 12 September. A possible anomaly was visible on 10 September. The anomalies suggested that lava-dome growth was continuing, although no activity was observed in partly cloudy satellite images during 12-13 September. The Volcano Alert Level remained at Watch and the Aviation Color Code remained at Orange. No current seismic information was available because Cleveland does not have a real-time seismic network. Observations made over the past several weeks show that the eruption of a lava dome has ceased or paused. Clouds have obscured the summit for most of the past week, but a weak thermal anomaly observed in satellite data on August 20 is consistent with slow cooling of the recently erupted lava dome. No evidence of ash emissions have been observed during this current period of unrest which began in mid-July, but remain a possibility. Short-lived explosions could produce an ash cloud that exceeds 20,000 ft above sea level. These events can occur without warning and may go undetected in satellite imagery for hours.On 9 August AVO reported that possible thermal anomalies on Cleveland were detected in satellite imagery. Cloud cover prevented observations of the summit area during 10-12 and 15-16 August, but several thermal anomalies were visible during 13-14 August. A scientist that flew 32 km N of the volcano on 14 August observed small white "puffs" of steam rising 30-60 m above the summit, even though most of the volcano was obscured by clouds. The Volcano Alert Level remained at Watch and the Aviation Color Code remained at Orange. No current seismic information was available because Cleveland does not have a real-time seismic network. AVO reported that on 2 August the Volcano Alert Level for Cleveland was raised to Watch and the Aviation Color Code was raised to Orange due to the formation of a 40-m-wide lava dome in the summit crater that was observed on 29 July. The lava dome was extruded sometime after 7 July following the last clear view of the summit area, however thermal anomalies observed since 19 July suggested that the dome had extruded since that time. On 31 March, AVO lowered the Volcano Alert Level and the Aviation Color Code for Cleveland to Unassigned noting that no eruptive activity had been confirmed during the previous few months. Neither significant thermal anomalies nor ash deposits on snow were observed in recent satellite imagery.The lack of a real-time seismic network at Cleveland means that AVO is unable to track local earthquake activity related to volcanic unrest. Unrest at Cleveland is frequent, and short-lived explosions with ash clouds or plumes that could exceed 20,000 ft above sea level can occur without warning and may go undetected on satellite imagery. Beautifully symmetrical Mt. Cleveland stratovolcano is situated at the western end of the uninhabited, dumbbell-shaped Chuginadak Island. It lies SE across Carlisle Pass strait from Carlisle volcano and NE across Chuginadak Pass strait from Herbert volcano. Cleveland is joined to the rest of Chuginadak Island by a low isthmus. The 1730-m-high Mt. Cleveland is the highest of the Islands of the Four Mountains group and is one of the most active of the Aleutian Islands.

U.S.A. - Mount St.Helens

February 17th, 2011

An M4.3 earthquake struck the Mount St. Helens region on the morning, 14 February 2011, at 10:35 a.m. PST (18:35 UTC) and was felt widely through southwestern Washington and Northwestern Oregon. Its exact magnitude may change by a few tenths from this value as records are further analyzed. The earthquake was followed by several aftershocks up to M2.8 over the next few hours the three largest of which were also reported felt. All of the earthquakes are located in an area about 8 kilometers (5 miles) north of the crater of Mount St. Helens, near the Johnston Ridge Observatory, at a depth of about 4 to 6 kilometers (2.5 to 4 miles). Earthquakes are in the same place as a small swarm that took place about two weeks earlier, on 29 January. These earthquakes are reminiscent of a swarm that took place about 30 years ago, when a swarm of small earthquakes began in August 1980, a few miles northwest of today's activity. The 1980-1981 sequence climaxed with an M5.5 earthquake on 14 February 1981. Analysis of the 1981 events suggested that they occurred along existing faults in the Mount St. Helens seismic zone, a northwest to southeast trending system of faults in which Mount St. Helens lies. The Mount St. Helens seismic zone exhibits strike-slip motion, with the southwestern rocks slipping horizontally northwest relative to the rocks northeast of the fault zone. The fault zone likely exerts control on the location of Mount St. Helens volcano. Studies following the 1980 eruption suggested that the magma removed during the May 1980 eruption and subsequent lava-dome building caused faults along the seismic zone to slip in response to the magma withdrawal. Similar interaction of volcanic activity and tectonic fault movement is possible in the case of today's earthquakes, but at present there appears to be no signs of unrest in the volcanic system. The 40-month-long lava-dome eruption of Mount St. Helens that began in autumn 2004 ended in late January of 2008. Earthquakes, volcanic gas emissions, and ground deformation are all at pre-eruptive background levels. The alert level and aviation color code were reduced to NORMAL/GREEN on July 10, 2008, following five months with no sign of renewed activity.
Even with the end of lava dome growth, some hazards persist. The new lava dome remains hot in places and capable of producing small hot avalanches or minor explosions that could dust areas with ash up to tens of miles downwind. Rock fall from the crater walls can produce clouds of dust that rise above the crater rim, especially during dry, windy days, as has happened in the past. Also, heavy rainfall or rapid snowmelt can send small debris flows onto the Pumice Plain north of the crater. (from CVO). Mt.St. Helens Live Cam

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ITALY - Etna volcano ( Sicily)

January 28th, 2012

At 11:24 GMT on 27 January 2012, an explosive emission of ash and hot material occurred from an eruptive vent within the New Southeast Crater (New SEC) of Etna, the first eruptive activity at this crater since the end of the 5 January 2012 paroxysmal eruptive episode. The first explosion was followed by others that were less intense, at intervals varying from a few minutes to more than one hour. An explosion at 21:40 GMT launched incandescent material in a narrow vertical jet to a few tens of meters above the crater rim; a much smaller Strombolian explosion occurred at 22:31 GMT. During the forenoon of 28 January 2012, sporadic ash emissions continued from the New SEC at irregular intervals, without any clear tendency toward an augmentation. Some of the emissions contain hot material, which appear as anomalies in the video images of the thermal monitoring camera of the INGV-Osservatorio Etneo (Catania) on the Montagnola, about 3 km south of the summit craters of Etna. The source of these emissions is a single vent located in the western portion of the crater floor. As of 15:30 GMT on 28 January, there is no evidence of lava overflow or strong Strombolian activity. Furthermore, the volcanic tremor amplitude continues to fluctuate at low levels, comparable to those of the preceding days. However, the current activity might well be a precursor to a new paroxysmal eruptive episode similar to those seen since January 2011. As of the 5th of January INGV reported that during the early morning hours of 5 January 2012, the New Southeast Crater of Etna has produced a new paroxysmal eruptive episode, following a period of quiescence of 50 days (the previous episode had occurred on 15 November 2011). This event, which had been preceded by many hours of weak Strombolian explosions within the crater, has repeated in most details its predecessors (i.e., lava fountains from multiple vents within the crater and on its southeastern and northern flanks, emission of lava flows toward southeast and northeast, generation of an ash and vapor column several km tall). Furthermore, the heavy fallout of pyroclastic material onto the flanks of the cone led to the formation of small pyroclastic flows, which invaded snow-covered terrain, provoking violent explosive interactions. Ash and lapilli falls affected mainly the southern flank of the volcano. A more detailed report will be posted here later today. As of the 15th of November, INGV reported that After a quiescent interval of 23 days, the New Southeast Crater (New SEC) of Etna reactivated on the morning of 15 November 2011 to produce its 18th paroxysmal eruptive episode since the beginning of this year. This episode has in nearly all details been a repetition of its predecessors, though with a few minor variations; the culminating phase lasted about one hour and terminated rather abruptly. Ash and lapilli falls affected the southeastern flank, including the towns of Zafferana Etnea and Acireale. The lava flow produced by this eruptive episode has followed the same path as those emitted during the previous episodes, toward the floor of the Valle del Bove, immediately to the north of the Serra Giannicola ridge, stagnating to the southwest of Monte Centenari. The flow reached a total length of little less than 4 km. The New SEC cone underwent further growth in height, mostly on its southern side, where at least 10 m of new material accumulated bringing the total height of the cone to about 180-200 m above its base. Previously, as of the 23rd of October, INGV reported that the seventeenth paroxysmal eruptive episode of 2011 took place at the New SE Crater (New SEC) of Etna during the evening of 23 October. Weak explosive activity was recorded at 1913, and at about 1935 small anomalies appeared in images recorded by thermal cameras. Explosive activity rapidly intensified at 1940 and by 2007 that crater was completely filled with lava. The lava overflowed through a breach in the E crater rim and traveled towards the Valle del Bove. On the afternoon of 8 October 2011, the New Southeast Crater of Etna produced its 16th paroxysmal eruptive episode since the beginning of this year; like its predecessors also this event has been brief and violent. This paroxysm came little less than 10 days after the previous episode, and it was of shorter duration than any of its predecessors in the series initiated in January 2011 - the culminating phase of sustained lava fountaining and ash emission lasted only about 20 minutes. Another notable feature of this event is the minor eruptive activity on the northeastern flank of the New SEC cone, which occurred along the fracture of 8 September, oriented SSW-NNE in its upslope portion and bending SW-NE in its lower portion. In contrast, the fracture that opened in this area during the 28 September paroxysm lies further to the west, cutting the flank of the "Levantino", a secondary cone formed in 2000-2001 on the north flank of the old SEC cone. The morphology of the New SEC did not undergo significant changes during this latest paroxysm, though it is likely that the accumulation of new pyroclastic material has led to some further growth in height of the cone. On the evening of 28 September 2011, the New Southeast Crater of Etna has produced its 15th paroxysmal eruptive episode since the beginning of this year. The culminating phase of this episode lasted less than a half hour but was more violent than those of the preceding paroxysms; on the contrary lava emission was rather minor, forming two small flows that reached the upper part of the steep western slope of the Valle del Bove. The ash plume was driven southwestward by the wind. Further details next. The 14th paroxysmal eruptive episode from Etna's New Southeast Crater has taken place on 19 September 2011, 11 days after its predecessor. This event, which occurred during rather poor weather conditions, produced lava fountains from various vents within the crater and on its southeastern flank, lava flows that descended the western slope of the Valle del Bove, an ash cloud that was bent by the strong wind toward northeast. Ash and lapilli falls were observed in the area to the north of Giarre. The main paroxysmal phase lasted from about 12:20 GMT (local time -2) until shortly after 13:00 GMT. On the evening of 19 September, weak spattering continued from a vent located at the southeast base of the Southeast Crater cone, and active lava flows continued to descend on the western slope of the Valle del Bove. After a relatively quiet interval of 10 days, a new paroxysmal eruptive episode has taken place at the New Southeast Crater (New SEC) of Etna on the morning of 8 September 2011. This was the 13th event of this type since the beginning of the year; the previous episode had occurred on 29 August 2011. Like its predecessors, this event generated a tall eruption column that was blown south-southeastward by the wind, leading to ash and lapilli falls over a number of population centers such as Monterosso, Viagrande, Trecastagni, San Giovanni La Punta, and the easternmost portions of Catania. Moreover, during this paroxysm lava overflows occurred not only, as usual, through the deep breach in the eastern to southeastern sector of the pyroclastic cone of the New SEC, but also from its northern rim, and brief, intermittent emissions of ash and water vapor took place from different spots - possibly new eruptive vents - on the north flank of the cone. Increasing activity started at about 8 am (local time). At about 8:58 am a lava flow went down slowly. Two new vents opened within the new Southeast crater : the first showed lava fountaining activity and the second only gas and ash emission. At about 9:19 a new vent opened on the North flank of the new Southeast cone. Then few later, a lava flow went down from this vent. At about 10;30 am the paroxysmal phase ended, but lava flows were still went down toward the Valle del Bove. This episode occurred 10 days after its predecessor, and it was particular for the rather brief phase of transition from weak Strombolian explosions to sustained fountains and generation of a tall eruption column. Another peculiar feature of this event were the short-lived explosive events from various spots on the northern flank of the New SEC cone, possibly related to the opening of new vents; however, the character of these events was rather different from the activity typically observed during the opening of new eruptive fissures, such as on 29 August, and in many previous paroxysmal eruptive episodes, foremost during the long series of paroxysmal episodes between January and August 2000. As of the 29 th of August, INGV reported that Nine days after the previous episode, the New Southeast Crater produced its 12th paroxysmal eruptive episode of the year on the early morning of 29 August 2011. This episode was particular for the opening of a new eruptive fracture on the southeastern flank of the pyroclastic cone surrounding the crater, along which several lava fountains shot up, and from which a broad lava flow was emitted that took a more southerly path compared to that of the earlier lava flows. The pyroclastic cone underwent major morphological changes due to the opening of the new eruptive fracture, which left a deep cleft in its southeastern flank. However, further growth occurred on the southern and northern rims of the crater. This episode produced a tall eruption column, which bent southeast, leading to ash and lapilli falls in population centers such as Zafferana Etnea, Fleri, Viagrande, and Trecastagni. The episode was preceded, as its predecessors, by initially very discontinuous and weak activity, which started with a single explosion at 00.52 GMT (= local time -2) on 28 August, followed from 15.17 GMT on by a series of ash emissions from the New Southeast Crater. At nightfall, sporadic, weak Strombolian activity was visible, which during the night showed a gradual intensification. At 03.15 GMT on 29 August, a first lava overflow occurred through the deep breach in the eastern crater rim, feeding a flow into the direction of the Valle del Bove. From 03.40 GMT onward, the Strombolian activity progressively intensified, and about 04.05, two vents within the crater emitted pulsating lava fountains up to 100 m high. During the following 10 minutes, these fountains increased significantly in height, and a dense eruption column rose a few kilometers above the summit of Etna before drifting toward south-southeast. At the same time, a small lava flow began to issue from the area affected by the collapse of a portion of the cone's east-southeast flank during the 20 August paroxysm. At 04.20 GMT, the southeastern flank of the cone fractured with the opening of a line of new eruptive vents down to the base of the cone, from which a row of lava fountains rose (see the image at top); soon thereafter a new, broad lava flow appeared, which was fed from the new vents, and which descended into the direction of the Valle del Bove, somewhat to the south of the lava flow emitted earlier during this episode. For the next 20 minutes, lava fountaining continued at all vents, both within the crater and along the new fracture, then the activity started to weaken from 04.30 GMT on. The lava fountaining from the vents within the crater passed into ash emission shortly after 04.40, whereas the lowest vent on the new eruptive fracture continued to produce incandescent jets until 04.50 GMT. Ash emission continued at a diminishing rate until about 05.15 GMT. Previous phase : eight days after the preceding episode, the New Southeast Crater has been the site of another paroxysmal eruptive episode on the morning of 20 August 2011 at 9 am (local time), the eleventh event of this type since the beginning of this year. This episode has been more violent than its predecessors, generating a column of tephra and gas that rose about 5-6 km above the summit of the volcano before moving southwest. The morphology of the cone growing around the crater has undergone significant changes, caused in part by the collapse of a portion of its eastern flank; furthermore it has further gained in height. Ash and lapilli falls occurred in the southwestern sector of the volcano. The lava flow went down to the East toward the Wall of the valle del Bove. The previous new paroxysmal episode occured last week at the Etna volcano. After an interval of relative quiet of 6 and a half days, the new Southeast Crater of Etna produced its tenth paroxysmal eruptive episode of the year during the forenoon of 12 August 2011. This event was, in its main characteristics, a repetition of its predecessors, with the emission of a lava flow toward the Valle del Bove, lava fountains several hundred meters high, and an eruption column that rose about 3 km above the summit. The ash plume was then blown southeastward, causing ash and lapilli falls in an area including the town of Zafferana and the coastal strip between Giarre and Acireale. As the previous phase, the activity has begun with lava fountaining which started today 12th of August at 10:50 AM (local time) acompanied by a lava flow which go down to the Valle Del bove. According to thermal data from INGV lava fountains rose at aboput 500-600 m high. Six days after its predecessor, a new paroxysmal eruptive episode has taken place at the New Southeast Crater (previously called "pit crater", located on the east flank of the old Southeast Crater cone) of Etna, during the night of 5-6 August 2011. In its main characteristics, this event has been a repetition of the previous paroxysms, with the emission of a lava flow toward the Valle del Bove, lava fountains exceeding 500 m in height, and an ash cloud blown southeast by the wind; however, this was one of the shortest and most violent paroxysms of the sequence initiated at the beginning of this year.(webcam video). A strombolian activity started at 6:30 pm (local time). Then a lava was emitted at about 10:40 PM toward the Valle del Bove wall. Lava fountaining maximum high 6'00m occured at 9:50 (TU). At about 11:15 Pm this eruptive activity declined. This ninth paroxysmal eruptive episode of the year at the New Southeast Crater has led to major growth of the pyroclastic cone that is building up around the crater, especially in its southeastern portion. The episode came 6 days after its predecessor, an interval that is very similar to those between the previous few episodes, but the "prelude" and buildup phase (Strombolian activity - lava flow emission) has been much shorter compared to the other events. On the evening of 30 July 2011, the eighth paroxysmal eruptive episode of this year took place from the crater located on the east flank of the Southeast Crater cone. The event was essentially a repetition of the previous paroxysms, with the emission of a lava flow toward the Valle del Bove, lava fountains rising to maximum heights of 450-500 m, and an ash plume that was blown by the wind toward east. The first signs of a resumption of eruptive activity from the crater were observed on the evening of 28 July, when sporadic, and very weak, Strombolian explosions took place; this activity ceased altogether during the night. Throughout the whole day of 29 July, the crater remained entirely quiescent. From the early morning hours of 30 July, an intermittent glow was visible at the crater, which progressively increased in intensity and frequency. At about 10.00 h (local time = GMT+2), the crater showed intense Strombolian activity accompanied by loud detonations, with lava bombs thrown several tens of meters up into the air and falling back into the crater or around its rims. Contemporaneously, a dilute plume of ash was emitted from the vent, which was blown eastward by the wind. Furthermore, a small lava overflow occurred on the eastern side of the crater, which travelled about 100 m and then rapidly chilled. This eruptive activity, which was accompanied by a distinct increase in the mean amplitude of the volcanic tremor, remained relatively constant until the early afternoon, after which an abrupt decrease occurred, both in terms of geophysical and volcanic activity. About 19.00 h local time, the mean amplitude of the volcanic tremor started to incrase again, and so did the Strombolian activity. At around 19.30, a dilute gas and ash plume was again blown eastward by the wind. The Strombolian activity progressively gained in intensity, quite more rapidly than during the morning's activity, and the incandescent jets became continuous around 21.30 local time. At the same time, renewed lava overflow toward east showed a rapid increase in effusion rate, forming a multilobate flow down the western slope of the Valle del Bove, which travelled approximately 3 km down reaching about 2000 m elevation by 23.00 local time. The ash plume became denser and was blown eastward by the wind, generating ash falls in the Ionian sector of the volcano.From 23.30 local time onward, the eruptive activity started to decrease in intensity, and ceased completely shortly after midnight. The lava flows, however, remained still mobile and incandescent for a few hours, due to gravitational flow on the steep slope, but then rapidly cooled because the lava flows were no longer fed from the vent. Details about the previous seventh paroxysmal episode from Etna's Southeast Crater :On the evening of 24 July 2011, vigorous Strombolian activity started within the crater located on the east flank of the Southeast Crater cone; this activity showed a gradual increase through the night, and culminated the next morning between 0230 and 0630 GMT (= local time -2) in a new paroxysmal eruptive episode. A lava flow started to travel through the breach left in the eastern crater rim by the previous lava overflows at about 0130; between 0230 and 0300 the Strombolian activity gradually passed into a pulsating lava fountain, accompanied by increasingly voluminous ash emission. During this time interval, the lava flow split into several parallel branches, following the same path as the lava flows emitted during the previous paroxysms, reaching the base of the steep western slope of the Valle del Bove near Monte Centenari. The lava fountain reached its maximum heights, fluctuating around 250-300 m, between 0400 and 0500 GMT, with a few jets rising up to 350 m high. The plume of gas and ash was blown eastward by strong wind, leading to ash falls in the area between the villages of Fornazzo and Milo on the mountain slope, and the Ionian coast near Riposto. As in the case of the preceding paroxysm (19 July), the final phase of this episode consisted of a prolonged series of violent explosions, which generated loud detonations heard over a wide area in the eastern and southeastern sectors of the volcano. This has been the seventh paroxysm from the same crater since the beginning of this year (the previous episodes had occurred on 12-13 January, 18 February, 10 Aprio, 12 May, 9 July, and 19 July); the interval between this and the previous episode. (From INGV). Previously, on 25th of July, INGV reported that the seventh paroxysmal eruptive episode of Etna of this year took place, again at the active crater on the east flank of the Southeast Crater cone, during the early morning of 25 July 2011. As during the preceding episodes, a lava flow was emitted into the direction of the Valle del Bove, and an ash plume was blown east by the wind. On the evening of 18 July 2011, Strombolian activity increased at the crater located on the east flank of the Southeast Crater cone, and culminated in a new paroxysmal eruptive episode between 0000 and 0230 GMT (= local time -2) on 19 July. As the previous five paroxysms, this episode produced a lava flow that spilled down the steep western slope of the Valle del Bove, following the same path as the lavas emitted during the preceding eruptive episodes, and stagnating at the base of the slope near Monte Centenari. Lava fountains rose up to 200-250 m high, producing heavy fallout of fluid spatter, resulting in the formation of several rheomorphic lava flows, the largest of which descended the south flank of the cone surrounding the crater, and reached its base. A dense plume of gas and ash was blown eastward by the wind. This has been the sixth paroxysmal episode from the same crater since the beginning of this year (the previous episodes had occurred on 12-13 January, 18 February, 10 Aprio, 12 May, and 9 July); the interval between the latest two has been only 9.5 days, much shorter than the intervals between the preceding events (4-8 weeks). During the day of 18 July, activity within the Bocca Nuova had diminished notably, after one week of intense Strombolian activity and the emission of a small intracrater lava flow. On the morning of 16 July 2011, a series of ash emissions from the active crater located on the eastern flank of the Southeast Crater cone marked the resumption of explosive activity within this crater, which produced loud booming sounds that were widely heard in populated areas on the slopes of Etna. This activity is occurring only one week after the latest paroxysmal episode, which took place at the same crater. Further updates on the evolving situation will be posted soon. At the same time, the Strombolian activity initiated on the evening of 11 July within the Bocca Nuova is continuing with slight fluctuations; during a field visit by INGV staff (Salvatore Giammanco e Boris Behncke) on the evening of 15 July, the Strombolian activity appeared slightly diminished compared to that observed two evenings before, but within one-and-a-half hours, the activity increased to levels superior to those observed on 13 July. Furthermore, immediately to the west of the explosive vent, a lava flow was observed, which was oozing from underneath a sheet of pyroclastics that were constantly deposited by the nearby Strombolian activity. The flow then cascaded into a deeper depression in the central-western portion of the crater floor. Dense gas clouds and the intense explosive activity precluded more detailed observation of this lava flow. As of the 5th of July, INGV reported that since 4 July 2011 weak Strombolian activity is taking place within the active crater located on the east flank of the Southeast Crater cone. Between 26 amd 29 June, the ash emissions from the BN diminished both in intensity and frequency, but resumed more vigorously on the morning of 30 June, with characteristics essentially identical to those of the period between 14 and 25 June. Also in this case, the images recorded by the thermal surveillance camera at the Montagnola did not show any hot material in the emissions. At the SEC, gas emission from the crater on the lower east flank of the cone was present since the beginning of the month, but showed a conspicuous increase on 22 June, and was accompanied by a series of small emissions of grayish brown ash. This degassing, often producing dilute ash plumes, continued until 27 June, and then nearly completely ceased. On the morning of 17 June 2011, sporadic ash emissions continued from a vent located on the floor of the Bocca Nuova, the westernmost of the summit craters of Etna. The same phenomenon has been observed during the limited periods of good visibility on all days since the onset of this activity, on 14 June 2011, and thus far shows no significant variations. The emissions occur every 5-15 minutes, producing small plumes of reddish to grayish brown, rather dilute ash. There is no evidence for the presence of hot material in these emissions. Seismic activity, in particular the volcanic tremor, is remaining at low levels. As of the 15th of June, INGV reported that after nearly 6 months of quiescence, ash emissions resumed at the Bocca Nuova - the westermost of the summit craters of Etna - on the early morning of 14 June 2011. On the previous day, mountain guides had heard loud hissing sounds coming from the interior of the crater, presumably caused by high-pressure gas emission. The first ash emission occurred at 05:45 (GMT = local time -2), and was followed by further emissions (the weaker of these set in parentheses) at 04:54, 05:41, 06:03, 06:19. 06:27, 06:43, 06:51, (07:05), 07:16, (07:21), (07:26), 07:32. 07:37, (07:40), (07:47), (07:58). After 08:00, the formation of dense weather clouds has prevented further visual observation. This activity generated small ash puffs, which rose no more than 200-250 m above the crater rim, before being pushed eastward by the wind. Movie footage recorded by the thermal monitoring camera at the Montagnola (EMOT) showed the complete absence of hot material in the emissions. The source of this activity appears to lie in the central part of the Bocca Nuova. In the meantime, the usual rhythmic emissions of gas and vapor from the Northeast Crater have continued, and conspicuous fumaroles were active on the upper east flank of the Southeast Crater cone, whereas the pit crater on the lower eastern flank of the cone showed weak vapor emission from its rims, mostly on its eastern side. As of the 13th of May, INGV reported that from 17:00 h (local time = GMT+2) on 11 May, the volcanic tremor amplitude progressivley increased, and around 20:30 lava started to overflow the east rim of the crater. During the following hours, the activity intensified, and shortly before 04:00 on 12 May culminated with lava fountaining, which generated an ash cloud driven south-southeastward by the wind. The phase of lava fountaining lasted around 2 hours, showing a gradual diminution around 05:45; an abrupt drop in the volcanic tremor amplitude at 06:10 marked the end of the eruptive activity.Four weeks after the latest paroxysmal episode, mild and discontinuous Strombolian activity has resumed at the pit crater located on the eastern flank of the Southeast Crater cone. This activity started on the morning of 8 May 2011, generating loud detonations that were audible to many kilometers away, such as the Monti Sartorius (northeast flank) and the town of Zafferana Etnea. After sunset, Strombolian explosions were seen to occur at intervals of 3-10 minutes, ejecting incandescent bombs up to a few tens of meters above the crater rim. During the night, some explosions threw bombs well beyond the crater rim, down to the base of the cone that has grown around the crater during the recent paroxysms. On the morning of 9 May, the Strombolian explosions continued without significant variations. As of noon on 9 May, the seismic activity and volcanic tremor amplitude at Etna show no changes.As of the 10th of April, INGV reported that the third paroxysmal eruptive episode of the year 2011 from the pit crater on the east flank of the Southeast Crater cone occurred on 10 April, 51 days after the previous paroxysm on 18 February. The event was essentially a repetition of its predecessors, with a lava flow probably exceeding 3 km in length, generation of a tephra and gas column, and intense lava fountaining. During the night between 9 and 10 April, the Strombolian activity within the pit crater gradually increased, as did the volcanic tremor amplitude recorded by the INGV-Catania seismic network. The lava flow produced by the overflow initiated on the evening of 9 April advanced very slowly, and at sunrise on 10 April had not yet reached the steep western slope of the Valle del Bove. During the forenoon of 10 April, the eruptive phenomena rapidly intensified, and a further significant increase in the volcanic tremor amplitude was observed, which culminated around 09.30 GMT (local time -2), with vigorous lava fountaining and the rise of an ash and gas column, which was blown by the wind to the southeast, causing ash falls in a sector between Trecastagni, Fleri, Zafferana, Aci S. Antonio, Acitrezza, Acicastello and Acireale. In this same interval, the rate of lava emission increased dramatically, producing a new flow that covered its predecessor before spilling down into the Valle del Bove, following essentially the same path as the lava flows of 12-13 January and 18 February. On its path, the lava flow locally encountered thick snow cover, which lead to violent explosive interaction that generated spectacular columns of vapor and ash. Intense eruptive activity and ash emission continued until sometime before 14:00 GMT, and were followed by a rapid decline; no eruptive activity has occurred since the late afternoon. Based on a NOTAM, the Toulouse VAAC reported that on 3 April ash from Etna rose to an altitude between 2.4-3.4 km (8,000-11,000 ft) a.s.l. Ash was not identified in satellite imagery. Since the early morning of 18 February 2011, a new episode of intense Strombolian activity is taking place at the Southeast Crater on Etna area. Starting shortly after 03:30 GMT (local time -1) on 18 February 2011, the thermal monitoring camera at the Montagnola (EMOT) of the INGV-Catania started recording thermal anomalies at the pit crater located on the lower east flank of the Southeast Crater cone; at the same time, the visual camera at the Montagnola (EMOV) showed intermittent glow indicating Strombolian activity. During the following hours, extremely bad weather has been preventing direct observation of the phenomenon. Simultaneously with the onset of Strombolian activity, the INGV-Catania seismic network on Etna recorded a rapid increase in the volcanic tremor amplitude, which is still at high levels at the time of this update (09:30 GMT). There are until now no observations of any lava emission, but ash falls have been reported from the Linguaglossa area on the northeast flank of the volcano. As of the 16th of January, INGV reported that during the day of 14 January 2011 no eruptive phenomena have been observed at the pit crater on the lower east flank of the Southeast Crater cone. At irregular intervals, small collapse events within the pit generated plumes of grayish-brown dust. As of the 14th of January, INGV reported that during the night of 12-13 January 2011 the pit crater on the lower eastern flank of the Southeast Crater was the site of a spectacular paroxysm, which produced sustained lava fountains, voluminous lava flows, and an eruption column several kilometers tall, which caused ash falls on the south flank of Etna. This event, whose phenomenology resembles that of numerous episodes observed during the past few tens of years at Etna's summit craters, marked the culmination of an episode of eruptive activity that had started about 18 hours earlier, and then gradually increased in intensity. The 12-13 January 2011 paroxysm is the first event of this kind since a powerful eruptive episode on 10 May 2008, which originated at the same pit crater, just a few days before the onset of the latest flank eruption of Etna (13 May 2008 – 6 July 2009). Look for fully report at www.ct.ingv.it . Starting in the late evening of 11 January, the seismic network recorded a slight increase in volcanic tremor amplitude. The amplitude peaked early on 12 January, and the source of the tremor shifted from a location N of the Northeast Crater towards the Southeast Crater. Weak Strombolian activity from the pit crater accompanied these changes on 11 January, and gradually became more intense on 12 January. As of the 7th of January, INGV reported that during the afternoon and evening of 5 January 2011 the activity of the pit crater located on the lower eastern flank of the Southeast Crater cone continued with very weak emissions of incandescent material (probably mostly hot gas with little or no solid material). Weak, intermittent glow was seen at the pit crater during the night of 5-6 January. The emissions are continuing as of the early afternoon of 6 January, at a slightly decreased frequency of 3-4 events per hour, producing small plumes appearing as minor thermal anomalies in the video footage of the INGV-CT thermal monitoring camera at the Montagnola (EMOT). Also on 6 January, there is intense degassing occurring from both the western vent of the Bocca Nuova (BN-1), and from the Northeast Crater, at the latter of which the emissions are taking place in a pulsating manner, generating numerous mushroom-shaped puffs of vapor. As of the 3rd of January, INGV reported that on the late afternoon of 2 January 2011, a strong glow appeared within the pit crater that is located on the lower eastern slope of the Southeast Crater cone, and during the following hours this evolved into vigorous, though modest Strombolian activity. This activity continued through the early morning, and decreased markedly after 06:00 local time (= GMT+2). The episode was accompanied by a significant increase in the volcanic tremor amplitude, which peaed around midnight and during the forenoon decreased to background levels. Between 23:00 on 2 January and 02:00 on the next day, the activity consisted of frequent Strombolian explosions (about 1-3 per minute), which launched coarse-grained incandescent material up to a few tens of meters above the rim of the pit. On a few occasions, incandescent bombs fell outside the pit's rim, mainly to the south and to the east. No outflow of lava occurred, and the event produced negligible quantities of volcanic ash. The episode of 2-3 January has been preceded by several days of repeated emissions of incandescent material, probably hot gas, from the same pit crater, and a dull glow was periodically visible during the night of 1-2 January. I t is furthermore possible that on the afternoon of 23 December 2010 a similar episode of Strombolian activity had occurred at the same pit, during a period of strongly increased volcanic tremor amplitude. However, bad weather precluded observations of the summit area; only in the video footage recorded by the Schiena dell'Asino monitoring camera a bright glow is intermittently visible between 16:00 and 16:05 of 23 December, located in correspondence with the pit crater.Previously, INGV reported that a strong explosion from the W vent of Etna's Bocca Nuova crater at 0446 on 22 December produced an ash plume that rose a few hundred meters above the summit and drifted NE. The explosion of hot, though not incandescent, material and subsequent ash emission was observed and recorded by thermal cameras at Montagnola and Nicolosi (14 km S). Light ashfall was reported as far away as Linguaglossa (18 km NE). Small emissions of reddish-brown ash continued to occur before noon As of the 15th of November, INGV-CT reported that following several days of minor ash emissions from the Northeast Crater - the tallest of the four summit craters of Etna, hereafter "NEC" - on the morning of 14 November 2010 there was a significant increase in both the frequency and in the volume of ash emissions from the same crater. These emissions generated plumes a few hundred meters high, which were then carried by the wind as a long, narrow trail, first toward southwest (14 November), then toward northeast (during the night of 14-15 November), and finally toward east (15 November). The emissions occurred in an intermittent manner, alternating with periods of white gas and vapor emissions. A visit to the summit craters was carried out by INGV-Catania staff on 15 November 2010, to make direct observations of the NEC activity and of the character of the ash deposits in the surrounding areas. Near the NEC cone, particularly to the south, in the northern portion of the Voragine, a few millimeters of brown ash were present on the ground. On the rim of the NEC itself, the deposit was up to 1 cm thick, especially on the eastern side. During the stay on the NEC rim, the ash emissions were rather modest, and accompanied by nearly continuous deep rumblings, sometimes becoming louder. Since more than a year, on the crater floor there had been an open degassing vent, which until the previous visit to the NEC in October had a diameter of about 25 m. On 15 November, this vent was seen to be much larger, with a diameter of at least 75 m. Ash emissions from this vent occurred at times in a passive manner, but at times became more vigorous. The inner walls of the crater were covered by reddish brown ash deposits. No coarse-grained material was observed, neither in the deposits, nor in the emissions. During the first week of October 2010, the activity of Etna has remained at fairly stable levels.  Deep-seated explosions continued within the deep pit of the Northeast Crater, though with significant fluctuations. The western vent of the Bocca Nuova was the site of a further explosive event at 11.27 (local time = GMT+2) on 7 October, which generated a minor amount of ash. Light ash falls were noted a few tens of minutes later in the Rifugio Sapienza area, at about 1900 m elevation on the south flank. The event was very brief and was not followed by other notable explosions or collapses during the following 24 hours. More or less continuous, sometimes pulsating gas emission occurred from the large collapse pit located on the lower eastern flank of the Southeast Crater cone. At the Voragine no significant activity occurred except for fumarolic activity on its crater rims. (www.ct.ingv.it). New Live cam Etna - Etna monitoring page

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ITALY - Stromboli volcano (Eolian Islands)

August 31st, 2011

During the first episode of spattering on 26 August, small rheomorphic lava flows formed repeatedly on the southeastern and northeastern flanks of the conelet. On 27 August, vigorous spattering reaching maxima between 09:20 and 10:35, and between 11:35 and 13:15 GMT, produced abundant fluid spatter, whose rheomorphic flowage covered the entire flanks of the conelet. Finally, a strong explosion from the northernmost vent of the crater terrace occurred at 05.06 GMT on 30 August, producing fallout of large pyroclasts up to the area of the Pizzo.During some of the episodes of more intense spattering between 16 and 19 August, repeated emplacement of small rheomorphic lava flows was observed on the southeastern flank of the cone, and on 18 August, a lava flow was emitted onto the slope of the Sciara del Fuoco (communication by the COA) where it descended for about 100 m. On 20 August, from 01:23 GMT, a sudden, strong increase in the spattering activity produced abundant flowage of still-fluid lava fragments toward northeast, on the crater terrace, forming a small lava field about 80 m long (see image below), which was fed until 14:00 GMT. The phenomenon was repeated at 21:38 on the same day and continued through the forenoon of 21 August. Little more than two days after the previous episode of intense spattering at Stromboli, a new episode started on the evening of 11 August 2011 at the small cone that sits on the southwestern rim of the crater terrace. This episode lasted for a few hours and terminated early on 12 August. Spattering started at 18.15 GMT on the 11th, producing a small lava flow due to the accumulation of abundant fluid spatter on the steep flanks of the cone, which descended its eastern flank toward the flat bottom of the crater terrace. During the following hours, the whole cone was covered with rheomorphic lava, also on its external side. Normal Strombolian activity continued during this episode from the other vents on the crater terrace.The lava flow that started during the night of 1-2 August 2011 from the northernmost vent of Stromboli lasted only a few hours; already during the afternoon of 2 August, the effusive activity ceased. The lava flow that descended the north flank of the Sciara del Fuoco had descended little below the small platform formed during the 2002-2003 eruption, stagnating about halfway down the slope. I n the morning of 9 August 2011, a new episode of weak spattering took place on the crater terrace of Stromboli, generating a small intracrater lava flow. This time the source of the activity was a vent located in the central portion of the crater terrace, where around 07.00 GMT (= local time -2) a weak but continuous spattering activity started, which soon was accompanied by the slow expansion of a small patch of fluid lava around the vent. At the same time, the normal explosive activity continued from the vents located in the northern and southern parts of the crater terrace. At about 08.00 GMT, a small branch of lava started to expand, at a rather slow pace, toward southeast on the flat surface of the crater terrace.The spattering activity continued until the late forenoon of 9 August; after 11.00 GMT no further expansion of the lava flow was observed, and the spattering had ceased. On the late evening of 1 August 2011, INGV reported that a conspicuous lava flow started to descend the northern slope of the Sciara del Fuoco at Stromboli. This marks the first lava effusion outside the crater terrace since the emission of a small lava flow in the night of 11-12 December 2010. Around 2100 GMT on 1 August, a vast accumulation of incandescent material appeared at the base of vent N1, the northernmost of the various active vents that lie within the crater terrace at about 750 m elevation on Stromboli. A few minutes later, this material started to collapse and slide, and then developed two small lobes of lava, the more easterly of which descended slowly on the steep slope of the northern portion of the Sciara del Fuoco, repeatedly generating collapse and small landslides derived from the loose material that the slope is made of. The lava then accumulated on the flat area where the hornitos of the 2002-2003 eruption had been located, before making its way down the steep slope below that flat area (as is shown in the two bottom frames in the figure above). On the late morning of 2 August, the lava flow had descended to about 500 m elevation and was advancing very slowly. During the early afternoon of the same day, feeding of the lava flow appeared to diminish. This lava flow represents the first major summit overflow at Stromboli for several decades, the most recent similar event being the eruption of November 1975. During the subsequent eruptions, in 1985-1986 and 2002-2003, lava effusion occurred from eruptive fissures on the upper northern slope of the Sciara del Fuoco, whereas in 2007, the main effusive vent was located at 400 m elevation. Differently from these eruptions, the usual Strombolian activity from the summit craters has not ceased with the onset of lava effusion on 1-2 August 2011. P reviously : on the early morning of 5 July, a strong explosion occurred in the southern crater area of Stromboli. The volcano is in a state of persistent eruptive activity, normally with explosions of medium to low intensity occurring from a number of vents located within the summit crater. During the month of June 2011, the activity continued at fluctuating levels, without, however, culminating in any major events. The activity was concentrated at the two active vent areas, in the northern and southern sectors of the crater terrace INGV-CT reported that on 17 February a series of strong explosions from the northernmost vent of Stromboli's summit area led to the accumulation of hot scoriaceous material on the external N flank of the crater. Activity continued at elevated levels from two vents in the northern portion of the crater terrace through 23 February. Stromboli volcano is in a state of persistent eruptive activity, normally with explosions of medium to low intensity occurring from a number of vents located within the summit crater. During the month of January 2011, the activity continued with strong fluctuations, culminating in four episodes of vigorous spattering and low lava fountaining, and emission of small intracrater lava flows. Previous episodes of increased activity, during December 2010, had occurred during the night of 11-12 December, with the emission of a small lava flow onto the upper south portion of the Sciara del Fuoco, and on 19 December, when a sequence of powerful explosions took place. During all of January 2011, two vents in the northern portion of the crater terrace, N1 and N2, produced jets of bombs and scoriae varying from 80 to less than 150 m in height, and a mean frequency of 1-5 explosions/h. In the southern portion of the crater terrace, various vents in shifting locations were active; initially only one large vent (S1) in the center of the southern crater area was erupting, but in the second half of the month it had transformed into three smaller vents. Explosions from this vent cluster occurred at a rhythm of 1-11 events/h, with maximum heights of the pyroclastic jets ranging between 120 and 200 m. INGV-CT reported that a sequence of three explosions from Stromboli's "S" vent in the S part of the crater terrace were recorded on 19 December by thermal monitoring cameras in Vancori and Pizzo. The first explosion ejected coarse-grained pyroclastic material, followed by fine-grained tephra, more than 250 m above the crater terrace. A slightly less intense explosion occurred less than a minute later. The third and weakest explosion ejected material 180-200 m above the crater, generating an ash plume that dispersed over the W and NE parts of the island. As of the 27th of October, INGV-CT bulletin reported that shortly after 09.35 h (local time = GMT+2) on 17 October 2010, continuous spattering started from what appared to be one of the two vents located at the northern extremity of the crater terrace of Stromboli. This activity continued for nearly two hours before gradually ceasing, and was followed by the intermittent explosive activity that is typical for this volcano.During the night between 18 and 19 October, the hornito located in the southern portion (on the side of the Sciara) of the crater terrace, began to produce vigorous spattering followed by the opening of a new vent at its base, from which issued a small lava flow. This lava flow travelled northward across the crater terrace, running against the base of the northern intracrater cone, after which it passed between this cone and the scoria cone of the southern vents. It then descended into a depression to the east, where it formed small, fan-shaped delta. The effusive activity continued at a low rate until the evening of 23 October. webpage www.ct.ingv.it. *************************************************************************************************************************

ICELAND - Katla Volcano

November 23rd, 2011

As of the 21st and 22nd of December, there has been some earthquake activity in Katla. While this earthquake activity is less then what have been taking place during the past few months this activity is bit higher then it used to be during the winter times. The largest earthquakes so far have had the magnitude around ML2.0. Currently this earthquake activity is limited to three areas inside Katla volcano caldera according to report from Iceland Meteorological Office. During the night of the 16th of November, 2011 there was a new earthquake swarm. This earthquake swarm is a part of ongoing pattern in Katla volcano. This pattern started after the small eruption that took place in Katla in July 2011. It was observed yesterday that there was a deep earthquake in Katla volcano, with the depth of 28 km. As of the 11 th of November, MET office reported that new dike intrusion has probably started in Katla volcano caldera. So far only few earthquakes have taken place. But the largest one so far is ML2.8 in size with the depth of 0.8 km (800 meters). But it seems that new area in the Katla volcano caldera has been increasing activity during past few weeks. Based on the number of earthquakes that are currently occurring . As of the 8th of November, MET office reported that At 09:50 UTC there was a ML3.5 earthquake in Katla volcano. According to news this earthquake was felt in Vík í Mýrdal town and on nearby farms. No harmonic tremor has been detected following this earthquake.Several local residents reported the quake. It was followed by another one measuring 2.5 points on the Richter scale. According to a statement from the Civil Defense Department, no further quakes were picked up by sensors in the area after 10:20 am yesterday. The IMO yesterday that there is no visible volcanic activity in the southernmost part of the Katla caldera but earth scientists continue to monitor the developments there closely. As of the 5th of October MET office reported that at 02:45 UTC a large earthquake swarm did start in Katla. The largest earthquake so far according to the automatic SIL systems is a ML3.9 earthquake. Katla webcam According to the news on Rúv it is now a opinion at Icelandic Met Office that a small eruption did take place in Katla volcano during the days 8 and 9 July 2011 (?). This eruption was however larger then the eruption in Fimmvörðuháls in Eyjafjallajökull volcano last year (2010). But this is only based on tremor data from around Katla volcano during this summer. But this is what Einar Kjartansson geologist at Iceland Met Office says in the news at Rúv. Even if this small eruption did take place in Katla volcano it does not seems to have eased the pressure inside Katla volcano, so a large eruption in Katla volcano is still a possibility in the close future. Note: GVP has updated Katla volcano eruption status to the year 2011. This conclusion was reached by checking out the cauldron that formed during this event. But they show a sign that they had a sudden melt taking place. But that melt can only happen of lava got into contact with the ice and fast melted it. This is also the reason why there was a 5 meters flood in Múlakvísl glacier river that did destroy the bride over it. But it is also a fact that the harmonic tremor in Katla volcano during this period was the same as that did happen during the eruption in Eyjafjallajökull volcano. The only difference was that it it was stronger from Katla volcano then in Eyjafjallajökull volcano it seems even if it lasted for a shorter time then in Eyjafjallajökull volcano. As of the 21st of September, IMO reported that, after few relative quiet days in Katla volcano new earthquake swarm started. This earthquake swarm did start with a ML2.8 earthquake at 10:55 UTC. This earthquake have been followed by smaller earthquakes. So far there have not been many earthquakes in this earthquake swarm. But the largest earthquake took place in the zone fissure where the eruption in the year 1918 took place. As of the 9th of september IMO reported that new eartquakes swarms occured.This earthquake swarm was in the caldera of Katla volcano, same as the earthquake swarms that have happened inside Katla volcano since July, when this pattern of activity did start. Two new earthquake swarms took place in Katla volcano today 28th of August. This earthquake started around 09:30 UTC this morning. Most of the earthquakes where smaller then ML1.0 in size. The depth was around 5.5 km on average. The largest earthquake was ML2.3 in size, with the depth of 5.5 km. That earthquake swarm was in Goðabunga area of Mýrdalsjökull glacier (Katla volcano). But here was also a minor earthquake swarm inside Katla volcano caldera. But in that earthquake swarm the earthquakes there where even smaller, most of those earthquake didn't reach the size ML1.0. The earthquake swarm in Goðabunga area in Katla volcano might be due to dike intrusion in that area. I do not know if this might be something else. But given the data, this is the most likely the reason for this earthquake swarm in this area. The earthquake swarm did stop at 12:47 UTC. After that everything has been quiet so far. As of the 27th of July, MET office reported that just before one o'clock this morning an earthquake measuring 3.2 on the Richter scale was centered under volcano Katla in Mýrdalsjökull. The origin of the quake was about 1.5 kilometers deep. There has been no indication of an imminent flood on meters. As of the 21st of July, Met office reported that during the night there was a small glacier flood from Mýrdalsjökull.Some minor harmonic tremor change was detected following this glacier flood. This even was small one, many times smaller then what did happen on the 8 to 9 July 2011. This glacier flood was detected around midnight 20 to 21 July 2011. According to information from the Icelandic Met Office, an earthquake registering 3.8 on the Richter scale occurred at 2:02:27 am on 18th of July in Myrdalsjokull glacier; it was followed by 15 aftershocks all occurring within the first 25 minutes. The Iceland Met Office and news sources reported that on 9 July a jökulhlaup from Mýrdalsjökull, the ice sheet that covers Katla, originated from three ice cauldrons in the SE part of the caldera. During previous weeks microseismicity had been registered near several of the ice cauldrons. Around the time of peak harmonic tremor, in the early evening on 8 July, the Mýrdalsjökull flood monitoring system indicated increased conduction. The water level reached the bridge around midnight and damaged the sensors. According to news articles, one new cauldron that had formed, along with cracks in the glacier around the cauldrons, may have been caused by a small eruption at Katla although no evidence of an eruption was observed. The jökulhlaup had destroyed a 128-m-long bridge and caused damage, resulting in the closing of part of the Ring Road. About 200 people were evacuated from the area but allowed to return home later that day. On 10 July the water had subsided and returned to normal levels. Katla volcano, located near the southern end of Iceland's eastern volcanic zone, is hidden beneath the Myrdalsjökull icecap. The subglacial basaltic-to-rhyolitic volcano is one of Iceland's most active and is a frequent producer of damaging jökulhlaups, or glacier-outburst floods. A large 10 x 14 km subglacial caldera with a long axis in a NW-SE direction is up to 750 m deep. Its high point reaches 1380 m, and three major outlet glaciers have breached its rim. Although most historical eruptions have taken place from fissures inside the caldera, the Eldgjá fissure system, which extends about 60 km to the NE from the current ice margin towards Grímsvötn volcano, has been the source of major Holocene eruptions. (GVN/GVP)

ICELAND - Grimsvotn volcano

May 30th, 2011

2011 NEWS - As of the 30th of May, IMO reported that on Saturday morning 28th of May at 6:30 UTC the volcanic tremor on Grímsfjall (Grímsvötn) rapidly decreased and had disappeared at 7 UTC. Since Thursday the tremor had been intermittent. Today, Monday 30 May, it has been confirmed by the participants of Iceland Glaciological Society's spring expedition that the eruption has ended. The end of the Grímsvötn eruption is set to 7 UTC Saturday morning 28 May 2011. Previously, as of the 26th of May, according to IMO there are indications that main eruptive activity ceased. There's no plume detected since 0300 GMT (11 p.m. EDT) and the last plume was around 0210 and since then there seems to be mainly steam coming from the crater and should calm within a few days. Previous IMO Update 25th of May :Yesterday evening there was still active explosivity in Grímsvötn. The activity is in three to four tephra cones surrounded by meltwater. The activity is pulsating with explosions producing ash clouds that rise up from the craters, some reaching a few km. The eruption plume is not continuous and all the material falls out nearby.yesterday evening 24th of May until 20:00 UTC, the ash plume did not reach higher than 5 km, but after that there were frequent pulses to 5-7 km. At 02:00 UTC the plume reached 12 km height, but after 2:20 UTC the plume has not been detectable on radar, except for an steam plume at 3:30 UTC, which reached 5 km. Eyewitnesses have reported small steam bursts from the crater today. Widespread ash in cloud layers have been detectable from plane between 5-7 km W of the volcano and also some ash haze below 3 km SW of the eruption site. .As of the 24 th of May the eruption is still continuing but the ash plume from the volcano on Vatnajökull glacier has dropped to five kilometers, from approximately 20 kilometers when the eruption was at its height.It was much lower last night than it was yesterday.Indications the level of ash production in the crater is much lower than in the past days. However, a significant amount of ash has fallen onto the country and ash is still present in the upper atmosphere, which is traveling towards the European mainland and will likely cause disturbances to flights in Britain and Scandinavia today. According to IMO report on 24th of May at 4 pm the ash plume was not visible on radar for most of the night and early morning due to weather conditions at the eruption site and around it. The estimated height is below 5 km since clouds over the glacier were at 5-7 km and the plume did not reach above the cloud deck. The ash plume reached 8 km briefly at 14 UTC, but decreased shortly there after. According to pilot reports the plume is visible at around 10 thousand feet, mostly light gray or brown in color, but pulsating to 15 thousand feet, and becoming darker in the process. Based on plume height, the estimated magma discharge rate equals 10- 70 tonnes/s of ash. A large part of Vatnajökull is covered by clouds and the eruption plume is not well defined in satellite images. South of Iceland images show visible ash extending over 800 km from the eruption site towards the south and southeast. Grimsvotn webcam - Update 23rd of May 7 pm :during the last hours, the plume has reached heights of 5 to 9 km, but northerly winds have been very strong which can effect the height. The amount of fallout is great from Vík in the west to the east of Öræfajökull. The amount of ash fall is the greatest close to the village Kirkjubæjarklaustur. Ash has been detected in several areas throughout the country, except in the northwest. The eruption has abated slightly since yesterday. No effusion of lava has been observed. The ash plume reached heights of 8 to 10 km last night and this morning. In the last hours, the plume has reached heights of 5 to 9 km, but northerly winds have been very strong which can effect the height. Heading: Most of the ash cloud heads to the south. At altitudes of 8 km and higher, part of the plume heads to the west. plume is Brown- or grayish and sometimes black close to the eruption site. : The amount of fallout is great from Vík in the west to the east of Öræfajökull. The amount of ash fall is the greatest close to the village Kirkjubæjarklaustur. Ash has been detected in several areas throughout the country, except in the northwest. A sample from Kirkjubæjarklaustur has been analyzed, which was taken around 1h on 22 May. The grains are glassy with micro crystals of plagioclase. Samples well sorted. Whole rock analysis: Basalt, with 50-51 Wt% SiO2 Leachate results: 5-10 mg/kg of waterdissolvable flour Grain size distribution: about 10% of the volume of the analyzed samples is finer than 10 micrometers. A total of 252 flights in Europe have been canceled because of the ash emitted by the Grímsvötn volcano in Iceland, most of which have been from Scotland to England. The ash has disrupted the travel plans of thousands of people. As of the 22 nd of May eruptive activity was still continuing. The ash plume reached heights of 15 to 19 km last night and on the morning then the plume has reached heights of 14 to 15 km, but from noon until 15:00 hrs (GMT), the plume reached heights closer to 10 kilometers. Most of the ash cloud heads to the south. Lower and scattered clouds head southwest and travel over the eastern part of the South Iceland Lowlands. The plume forms a 60 km long circular cloud around the eruption site with its lower boundary at a height of about 5 km. Out from this cloud, a scattered cloud lies to the north reaching about 450 km north of the eruption site at 14:54 hrs. The amount of fallout is massive east from Kirkjubæjarklaustur west to the center of Mýrdalssandur. The visibility is virtually zero. The fallout is most concentrated south of the volcano where the heaviest particles fall out fastest. The fallout is less dense north and east of the volcano.As of the 21st of May, a new eruption began at Grímsvötn volcano at approximately 17:30 UTC, according to Icelandic Met Office. An accompanying pictures show the earthquake activity and the size of the ash cloud at 22.00 (10 PM). Eruptions in Grímsvötn start as subglacial eruptions, which quickly break the ice cover. At 21:00 UTC, the eruption plume had risen to an altitude of over 65,000 ft (~20 km). Initially, the plume is expected to drift to the east and subsequently to the north-east. An image from the Icelandic Met Office weather radar located at Keflavik International Airport, at 220 km distance from the volcano shows the volcanic cloud extending above a large part of Vatnajökull ice cap. Initial overview flight, with limited visibility, and earthquakes locations suggest an eruption site in the southwestern part of the Grímsvötn caldera. Ice cover there is relatively thin (50-200 m) and meltwater is anticipated to accumulate within the Grímsvötn caldera lake. From there, it may eventually drain in a sudden glacial outburst flood, jökulhlaup, along a subglacial channel and issue from the Skeiðarárjökull outlet glacier. The height of the initial plume in the present eruption, 17 km, is much higher than in a preceding eruption at Grímsvötn in 2004. Then an eruption produced a plume reaching an estimated height of 6-10 km above vent. The present plume during afternoon is also higher than recorded in the Eyjafjallajökull eruption in Iceland last year. Earthquake meters showed clear “volcanic unrest” around 6 PM on Saturday. Even though the Grímsvötn volcano is very active the eruptions are usually rather limited in scope. The eruptions are usually rather short, from one to three weeks in duration. Most of the time the eruptions are followed by floods which sometimes cause damage in roads and bridges. The area affected is sparsely populated and there is no report of any human casualties in recent times. The eruptions have had almost no effect for the moment on international air trave, only Iceland airport traffic has been disrupted. Airplanes do of course have to avoid the surrounding area, but the circle has been very limited in previous eruptions.The last eruption in Grímsvötn occurred in November 2004. Grímsvötn is Iceland's most frequently erupting volcano. Grímsvötn, Iceland's most frequently active volcano in historical time, lies largely beneath the vast Vatnajökull icecap. The caldera lake is covered by a 200-m-thick ice shelf, and only the southern rim of the 6 x 8 km caldera is exposed. The geothermal area in the caldera causes frequent jökulhlaups (glacier outburst floods) when melting raises the water level high enough to lift its ice dam. Long NE-SW-trending fissure systems extend from the central volcano. The most prominent of these is the noted Laki (Skaftar) fissure, which extends to the SW and produced the world's largest known historical lava flow during an eruption in 1783. The 15-cu-km basaltic Laki lavas were erupted over a 7-month period from a 27-km-long fissure system. Extensive crop damage and livestock losses caused a severe famine that resulted in the loss of one-fifth of the population of Iceland.

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SPAIN - Hierro island (Canary)

February 2nd, 2012

Instituto Geográfico Nacional (IGN) reported that during 25-31 January the submarine eruption continued S of El Hierro Island. Mean tremor amplitude maintained very low values during this report period. Frequent and
persistent emissions of large steaming lava fragments were observed on the sea surface, some of them about 3 m wide. Seventy-eight seismic events were registered during this period, most of them located in the central part of the island, with offshore events extending primary to the S. Depths of the hypocenters varied between 10 and 23 km, and magnitudes between 0.4 and 2.8. Analyses of GPS deformation showed stability both in vertical and horizontal components. Instituto Geográfico Nacional (IGN) reported that during 18-24 January the submarine eruption continued S of El Hierro Island. Mean tremor amplitude has oscillated considerably since 19 January, including abrupt changes from rather high values to periods of almost no tremor which lasted a few hours. Emissions of large steaming lava fragments were observed every day of this report period. Thirty-two seismic events were registered during this period, most of them located in the central part of the island, extending offshore to the S, at depths between 8 and 19 km with a maximum magnitude of 2.2. Analyses of GPS deformation showed stability both in vertical and horizontal components. As of the 20th of January, new bathymetric images were published. Instituto Geográfico Nacional (IGN) reported that during 11-17 January, the submarine eruption continued S of El Hierro Island. The mean amplitude of the tremor moderately increased during the week. Eighteen seismic events were located during this period, two of them felt by residents of the island. Most of the events were grouped in the central part of the island, extending offshore to the S, at depths between 6 and 29 km, with a maximum magnitude of 2.5. Analyses of GPS deformation showed stability both in vertical and horizontal components.Instituto Geográfico Nacional (IGN) reported that during 4-10 January, the submarine eruption continued S of El Hierro Island. The mean amplitude of the tremor slightly increased during the week. During this period, large floating lava fragments were observed close to the vent area and generating steam. The production of these fragments was especially intense during 6-8 January. Nineteen seismic events were located during this period, most of them were grouped in the central part of the island, extending offshore to the S, at depths between 10 and 18 km, with a maximum magnitude of 2.0. GPS data analyses showed little deformation, with a trend to subsidence in the stations at the S of the island. Instituto Geográfic Nacional (IGN) reported that during 28 December-3 January, the submarine eruption continued S of El Hierro Island. The tremor signal almost disappeared for a few hours on 28 December, after three hours with pulses every 30 seconds. The tremor amplitude started increasing again at approximately 16:35. Most of the days, large lava fragments and fine material could be observed on the emission area. Twenty-four seismic events were located during this period, most of them grouped in the central part of the island, extending offshore both to the N and S. The depth of most of these events ranged between 9 and 23 km, with a maximum magnitude of 2.5. GPS data analyses showed very little deformation, with a slight trend to the N in the stations located at the N of the island. Instituto Geográfico Nacional (IGN) reported that during 21-27 December the submarine eruption continued S of El Hierro Island. The mean amplitude of the tremor signal remained stable during the week. Twelve seismic events were located during this period, most of them offshore, both to the N and S of the island, at depths between 12 and 26 km with a maximum magnitude of 2.8. GPS deformation data analyses showed stability in the horizontal components and trends to stability in the vertical component. Instituto Geográfico Nacional (IGN) reported that during 14-20 December the submarine eruption continued S of El Hierro Island. During the beginning of the week, high-amplitude pulses were registered in the tremor signal every 5-10 minutes. On 15 December there were two long pulses around 7 minutes each, and after the second one the mean tremor amplitude values remained similar to those of previous weeks. Six seismic events were located during this period, both offshore to the N and inland, at depths between 3 and 22 km. GPS deformation data analyses showed stability in the horizontal components and deflation in the vertical component. As of the 16th of December, IGN reported that the amplitude tremor signal dropped yesterday from 7:30 PM but today morning re-increased to a moderate signal. Instituto Geográfico Nacional (IGN) noted that during 7-13 December the submarine eruption continued S of El Hierro Island, with steaming lava fragments sporadically observed floating on the sea. During this period, the mean tremor amplitude oscillated between decreasing and increasing trends during the first days of the week, and since 10 December high-amplitude pulses occurred every 5-10 minutes. Only seven seismic events were located during this period, most of them offshore to the N of the island at depths of 17-23 km and with a maximum magnitude of 2.0. GPS data analyses showed stability in the horizontal components and trends to deflation in the vertical component. Instituto Geográfico Nacional (IGN) reported that during 30 November–6 December the submarine eruption continued S of El Hierro Island, with lava balloons sporadically observed floating on the sea. During this period, the mean tremor amplitude was similar to the previous week. Twenty-eight seismic events were located, most of them offshore to the N of the island at depths of 15-24 km and with a maximum magnitude of 2.8. Only one of these events was felt by residents at a maximum intensity value of II using EMS-98 (European macroseismic Scale). GPS data analyses showed stability in the horizontal components; the vertical component at stations located on the S and NE parts of the island showed subsidence. (webcam) .As of the 1st of December, IGN reported that a short phase of increasing activity (2 hours) in the morning generated new pillows lava at the sea surface. Few large size fragments could be observed floating simultaneously. Instituto Geográfico Nacional (IGN) reported that during 23-29 November the submarine eruption continued S of El Hierro Island. During this period, the mean amplitude of the tremor showed a slight increase. (INVOLCAN) has created a new video channel for Hierro. As of the 28th of November IGN reported that from Sunday afternoon to Sunday evening the submarine activity increased and many pillows lava flotting at the sea surface were visible ( photo) however the eruptive tremor showed no significant change during this phase. On 26 November large steaming fragments of lava appeared intermittently floating over the emission center. On 27 November, the emissions were more intense and a few hundred fragments could be observed floating simultaneously, with mean dimensions between 0.5 and 2 m. Some samples of the fragments were collected from a ship near the emission area. During the period, 121 seismic events were located, most of them offshore to the N of the island at depths of 15-23 km and a maximum magnitude of 3.3. Seven of these events were felt by residents at a maximum intensity value of III using EMS-98 (European Macroseismic Scale). GPS data analyses trended towards stability in the horizontal components, while in the vertical component most of the stations showed subsidence while stations in the NE of the island also trended towards stability. As of the 23rd of November, Instituto Geográfico Nacional (IGN) reported that during 16-22 November the submarine eruption continued S of El Hierro Island. During this period, the amplitude of the tremor showed two rapid changes, a decrease in amplitude at 2200 on 17 November and an increase at 1710 on 19 November. Seismic amplitudes decreased between late 20 November and mid-day on 21 November, and then remained stable at values similar to those noted during 19-25 October. Superficial activity over the emission center was rare, characterized by alternating days without seawater discoloration and days where there was minor gas and tephra content in the water and persistent discoloration. During the period, 200 seismic events were located, most of them offshore to the N of the island at depths of 16-23 km and a maximum magnitude of 3.7. Seventeen of these events were felt by residents at a maximum intensity value of III using EMS-98 (European Macroseismic Scale). GPS data analyses showed little deformation in the horizontal components, while in the vertical component stations located in the N of the island showed uplift and the rest showed subsidence. (webcam) As of the 11th of November, IGN reported that the submarine activity close to the South of the Hierro island was still continuing without significant changes. But new fact is that during the past days many earthquakes also occurred to the North of the island, close to the Frontera village. This important seismic activity was accompanied by gas emissions from several fissures around the village. As of the 9th of November, IGN reported that the eruptive activity was still continuing. The eruptive tremor increased today in the La Restinga area. Yesterday, 8th of November 16 h GMT a gas bubble about 25 m high was observed at the sea surface. About 17GMT another gas bubble was visible. (video). Both was accompanied with a strong sulphur odor (H2S). Some of the most recent estimations published reported that the vent will be at about 70 m from the surface (?). Instituto Geográfico Nacional (IGN) also reported that during 2-8 November the submarine eruption continued S of El Hierro Island. Tremor amplitude reached higher values than during previous weeks, getting closer to the values detected during 11-12 October, just after the beginning of the eruption. During 2-8 November, 364 seismic events were recorded, most of them located offshore to the N of the island, at depths of 16-23 km. The maximum magnitude was 4.4, and 32 of these events were felt by residents at a maximum intensity value of V using EMS-98 (European Macroseismic Scale). The total number of located events since 17 July was 11,294. GPS deformation analysis showed trends towards no deformation during the first days of the reported period, and a slight trend towards deformation to the S at the stations located on the N side of the island in the last days. Close to sunset on 5 November, big bubbles rose to the sea surface and ejected sea water and volcanic material a few meters above the water. Some new video images of the area shows small explosive plumes/jets from the ocean surface that suggest the eruption could be entering a Surtseyan phase (?). Volcano ash is to be expected while water can still get into the crater. As of the 4th of November, information reported that it seems that the eruption is gaining strength and power. The harmonic tremor on the seismometer located on the El Hierro Island it self has started to get saturated again. It also have been unconfirmed reports of the south fissure growing in size (?). As of the 3rd of November, the eruption continued. The first eruption vent that did open south of El Hierro Island has continued to erupt during the past days. As many web images can attest, the stains in the Atlantic Ocean persist, with a strong indication that at least limited degassing is occurring at the original vent sight. A new vent was imaged with sonar to show a new cone with an associated lava flow with almost the same morphology of the terrestrial scoria cones that are scattered on the island itself. Since yesterday, November 2nd, around 06:00 UTC the harmonic tremor has been increasing. During the past two weeks the earthquake activity have been growing in the North-west part of El Hierro Island. The largest earthquake so far took place this morning, it size was ML4.0 with the depth of 20 km. As of the 30th of October, IGN reported that the current tremor data now suggests that a new vent or vents could open up just outside north-west coast of El Hierro volcano island. Instituto Geográfico Nacional (IGN) reported that during 26 October-1 November tremor continued to be registered by every seismic station on El Hierro Island; 540 seismic events were registered and located, and the mean amplitude increased slightly during the last two days. Most of the events were located offshore to the N of the island, at depths of 16-23 km. The maximum magnitude was 3.9, and 36 of the total events were felt by residents at a maximum intensity value of IV using EMS-98 (European Macroseismic Scale). The total number of located events since 17 July was 10,930. Preliminary analysis of GPS deformation data showed an inflation-deflation sequence at one station on the N side of the island, with the main deformation trending N-S and in vertical components. GPS stations located in the W and S showed different behavior, with mean deformations to the SW and NE, respectively. First digital image. Since 21 October, most of the events were located in the N part of the island, aligned NNW-SSE from the center of the island to around 13 km offshore. Most of these earthquakes occurred around 20-25 km depth. Superficial analysis of GPS deformation data from the last few days of the reporting period showed different behaviors between the stations located at the N of the island and the station located at the S, close to the submarine eruptive vent. As of the 22nd of October, IGN reported that eruptive tremor increased. Huge bubble reapeared at the sea surface since yesterday. Alert level remains at red lavel for the Restinga area. As of the 20th of October local newspaper confirmed that the eruptive activity seems decreased regarding tremor signal and seismicity, however IGN reported from this morning 3:00 am slight elevation of the tremor occured. Instituto Geográfico Nacional (IGN) reported that tremor, registered by every seismic station on El Hierro Island, continued during 12-18 October. Deformation decreased during this period, with significant inflation-deflation episodes registered by the stations located in the NW part of the island. In the same area, during 15-17 October, frequent episodes of emission, forming big turbulent rings of gas and foaming, were observed on the sea surface. Since the night of 17 October, the amplitude of the tremor signal had decreased slowly. On 18 October, deformation further decreased and the sea-surface disruption from gases was not observed. As of the 17th of october, IGN reported that from 10h45 am, villagers noted huge bubble forming in the sea. This phenomenon was visible from the road to La Restingua, become checkpoint of the Civil Guard.. These large bubble are probably related to higher gas emission. This type of activity seems similar with the underwater eruption off the coast of Teirceira in 2000 ( read SVE article about this mission). Fluctuation observed in the tremor may indicates explosisions in connection with a move toward the surface to 100 m depth (?). According to some observers, during the weekend pillows lava where floating on the ocean. As of the 14th of October, the volcanic tremor remains at the same level. New video shows the effect of the submarine activity at the sea surface. The Spanish geographic institute reported two large sea stains that were caused by the eruption coming through two openings. According to CSIC scientist the fissure might propagate closer to the coast with time, but there is no danger until the rift is under 50-60 meters of seawater, rather than the ~200 meters of the shallowest part now. At 50-60 meters, the chances of explosive eruptions increases as the seawater and magma interact in shallower conditions. The threat of an eruption on Hierro island has eased after pressure in the area was reduced following the present undersea event. As of the 13th of October, it seems that eruptive activity from Hierro submarine is still continuing but dropped from yesterday. However, also it seems this activity migrated closest the South coast of Hierro. Yesterday, people reported strong smell of sulfur and discoloration of the sea surface at about 2,5 km off La Restinga - Video .Spain's Instituto Geografico Nacional (IGN) confirmed on Tuesday afternooon that an underwater eruption is occurring 3 miles (5km) off the southern coastline of El Hierro, the smallest of the Canary Islands, which are located in the Atlantic off the coast of Morocco. IGN confirmed that all three of its seismic stations on El Hierro registered low frequency volcanic tremors in the south of the island at the southernmost village in the Canaries, La Restinga. The present volcanic activity is believed to be occurring at a depth of nearly 2,000 feet (600 meters) below sea level. Scientists from ING, CSIC, and the University of Cadiz are trying to determine if the subsea volcanic vent is widening and, if so, if it is widening in the direction of El Hierro. Officials on Spain's El Hierro Island in the Canaries said on Tuesday that they are evacuating some 600 residents from a small coastal town due to volcanic activity in the area. On Tuesday morning this eruption was only been confirmed by harmonic tremors seen on seismometers on El Hierro island. Based on the harmonic tremor plots, it seems that the eruption has been growing in size since it started well over 12 hours ago. At 04:18 UTC on 10 October, 2011 it seems a submarine eruption started somewhere close to the El Hierro volcano Island (but inside El Hierro volcano system). As of the 10th of October local paper reported that four ships have alerted the maritime authorities of the existence of possible volcanic activity (unconfirmed yet), four miles south of La Restinga (El Hierro) and about 500 meters deep. The latest data collected by the National Geological Survey stations on the island of El Hierro suggest a submarine eruption up to 2,000 meters deep in the Las Calmas area. Spanish scientists from IGN are going to try get some special undersea cameras out to El Hierro to confirm or not the activity. This eruption looks to be fairly benign in terms of threat to life and property, but very little is known about the nature of the eruption so far. El Hierro has suffered, since mid-July 2011, around 9,600 earthquakes caused by magma activity in the base of the island, the strongest of them on Saturday night, which reached a magnitude of 4.3 degrees on the Richter scale. If confirmed, this eruption will be the first recorded in Spain since 1971, when the Teneguía volcano emerged on the island of La Palma. (news next). Instituto Geográfico Nacional (IGN) reported a drastic increase in the seismic activity at Hierro during 27 September-3 October, with more than 1,100 new seismic events detected, 83 of them felt by residents, with a maximum intensity value of IV using EMS-98 (European Macroseismic Scale). Most of the hypocenters were located offshore, SW of the island, at around 14 km depth. The maximum magnitude recorded during this week was 3.8. The total number of located events had reached more than 9,300 since the anomalous activity began on 16 July. The superficial deformation measured by the GPS network had reached 35 mm. Instituto Geográfico Nacional (IGN) reported more than 900 new seismic events at Hierro during 20-26 September, five of them felt by residents. The maximum magnitude recorded was 3.4. The total number of located events had reached more than 8,100 since the anomalous activity began on 16 July. The rates of both GPS deformation and seismic energy release had significantly increased during the previous seven days. On 23 September, the Canarian Autonomous Government raised the Alert Code to Yellow. As of the 23rd of September, The local authorities at have raised the alert status to yellow based on increased seismicity - both in terms of number of earthquakes and intensity, some earthquakes as large as M3. This new alert level means that the government of the island will release regular updates on the activity and make sure that appropriate emergency measures are in place. As of the 21st of September, IGN reported that more than 900 seismic events at Hierro island during 8-19 September, three of them felt by residents. The total number of located earthquakes had reached more than 7,200 since anomalous activity began on 16 July, with patterns alternating between relatively calm and high-energy periods (4D animation eathquakes between July and September). The GPS local network showed similar deformation rates compared to previous weeks. The Spanish Geographic Institute (IGN) reported that since 16 July, seismicity at Hierro was high above the background levels. Until 7 September more than 6,200 events had been located, most of them in the El Golfo area with hypocenters that were 10 km deep, all magnitudes were below 3. The seismic activity alternated between relatively calm periods and high-energy periods. GPS local network stations showed deformations of about 2 cm. High rates of carbon dioxide flux were measured in the anomalous area. The triangular island of Hierro is the SW-most and least studied of the Canary Islands. The massive Hierro shield volcano is truncated by a large NW-facing escarpment formed as a result of gravitational collapse of El Golfo volcano about 130,000 years ago. The steep-sided 1500-m-high scarp towers above a low lava platform bordering 12-km-wide El Golfo Bay, and three other large submarine landslide deposits occur to the SW and SE. Three prominent rifts oriented NW, NE, and south at 120 degree angles form prominent topographic ridges. The subaerial portion of the volcano consists of flat-lying Quaternary basaltic and trachybasaltic lava flows and tuffs capped by numerous young cinder cones and lava flows. Holocene cones and flows are found both on the outer flanks and in the El Golfo depression. Hierro contains the greatest concentration of young vents in the Canary Islands. Uncertainty surrounds the report of an historical eruption in 1793. (GVN/GVP)

FRANCE - Piton de la Fournaise (Reunion island)

December 11th, 2010

As of the 10th of December 130PM, OVPLF reported that the eruption already ended. No tremor signal has been recorded since this hour. As of the 9th of December, following a seismic crisis and inflation a new eruption started at 730 PM (TU) from an eruptive fissure oriented North-South and located just above puy Mi-Côte, at about 2500 m elevation. The eruption was characterized by laval fountaining and two lava flows emission. As of the 31st of October. OVPLF reported that the eruption ended. Seismic signal associated with the eruption and degassing ended at 10:50 in the morning. As of the 29th of October, OVPLF reported that observation carried out during a fligh above the volcano showed that a part of the summit cone 3 (only active now) collapsed. Some lava ejecta and gas emissions occured from this cone which contained a small active lava pond. The eruptive activity was feeding a small lava flow with slow movement. A part of this lava flowed in a lava funnel close to the active crater. The lava field remains upstream of the cone named « Gros Benard ».As of the 28th of october, OVPLF reporteds that the eruption is sill continuing and charaterized by a sudden increasing activity and tremor since yesterday 4:30 PM. As of the 26th of October, OVPLF reported that the eruptive activity is still slowly continuing in the same area. No change occured during the past days. As of the 22nd of October, OVPLF reported that activity is continuing close to the Château Fort area, South part of the Enclos Fouqué. Now, only one cone is active et only few lava fountains observed. Volcanic tremor was stable. No earthquakes was recorded yesterday. GPS ground deformation showed a weak deflation under the volcano. As of the 20th in the morning, OVPLF reported that the eruption is still continuing. Eruptive activity is still characterized by low lava fountains from the main events along the fissure. Lava flows field extending East-Southeast at distance about 2 km. Volcanic tremor remains stable. As of the 19th of October, OVPLF reported that eruptive activity is still continuing without important changes. Weak ejection and small lava fountains still occurs from the main eruptive vents located along the eruptive fissure ; lava flows go down slowly toward the East-Southeast. The explosive activity and degassing dropped. The volcanic tremor remains stable. As of the 18th of October, in the morning, OVPLF reported that eruptive activity was still continuing, but the explosive and degassing phase decreased since yesterday 17th of October. The volcanic tremor also decreased (1/7 in comparison from the beginning of the eruption). The number of volcano tectonic events remained low (7/day); the most important event occured at 11:23 PM with a mag 1.4 and localized at about 1600 m depth under the summit crater Bory. The base and the summit of the volcan remained in inflation. Preliminary estimation of the lava volume emitted was 600.000 m3. As of the 16th on the morning, OVPLF reported that eruptive activity is still continuing and characterized by low lava fountains along the eruptive fissure which feeding a lava moving towards the East, Southeast. Lava is issued from an area close to the old crater of Chateau Fort at the base Southeast of the flank of the Dolomieu crater and remains within the enclos Fouqué. Four small cones were active along the eruptive fissure, and lava fountaining occured from three of them. The lava flow run slowly about 1,6 km toward East and Southeast and gets closer to the break of slope of the " Grandes pentes".Temperature measurement carred out by a team of the OVPLF showed 1100°C. The volcanic tremor remained stable. (OVPLF full report in french). As of the 15th of October OVPLF reported that a new eruption started yesterday 14th of October since 7:10 PM. The eruptive activiy is localized close the Chateau Fort, within the Enclos Fouqué, Southeast of the Dolomieu crater. During the day of the 14 October, the observatory recorded an increasing seismicity between 4h AM and 2 PM. Then, a seismic crisis occured (more than several hundred earthquakes) occured between 2 PM and 3:45 PM. During this phase important ground deformation occured close the summit and generated many rockfalls inside the Dolomieu crater. At 14:11 PM, the seismicity moved toward the Southeast part of the volcano (Chateau Fort). As of the 15th in the morning the ereutive activity was still continuing. According to OVPLF this eruption is associated with a dyke intrusion beneath the summir crater Dolomieu. As of the 27th September, OVPLF reported that following a decrease of the seismicity, the alert level has been dropped. As of the 24th of September, OVPLF reported that probably an eruption is impending. During the night, between 2 am and 3:50 am (a local time GMT 4) a seismic crisis was observed on the volcano. A Series of several tens of earthquakes was localized directly below the summit zone, under the crater Dolomieu. From 5 h local time a slighly decrease of this seismicity occured.The seismic crisis was associated with inflation (approximately 3 cm) of the volcano, in particular close the summit part. The most significant deformations were measured on the edge and the north side of the Piton de la Fournaise and also on the south edge. These data indicate that a distribution of the magma towards the surface took place directly below the volcano. (Dolomieu). The magma did not reach yet the surface ( Friday 5:15 (GMT+4) . Starting on 14 August and continuing through 10 September, OVPDLF recorded a slow but steady increase in the number and magnitude of earthquakes from Piton de la Fournaise. Inflation of the summit area began in late August. A report on 13 September noted localized deformation W of Dolomieu crater and a small number of landslides in the crater. On 20 September a significant increase in earthquakes was recorded, although the average magnitude was low. The earthquakes were located at the base of Piton de la Fournaise, W and S of Dolomieu crater. PREVIOUS NEWS : as of the 12th of January 2010, OVPLF reported that the eruption ended. Following a slight increasing of the eruptif tremor yesterday, eruption within the Dolomieu crater dropped during this night at about 2 am. Nowthe moment only a weak degassing occurs. As of the 7th of January, the volcanic eruption begun January 2nd of this year is always was still progress in the crater Dolomieu. Yesterday evening, the eruptive trémor weakly increased but remained stable. As of the 5th of January, OVPLF reported that intensity of the at present current volcanic eruption in the sommital crater Dolomieu is stable. It is however necessary to indicate from time to time some renewals of activity comparable to one pulse of more important intensity. This day two of these phases were observed at 9:30 am and 11:30 am (GMT 4).A mission of measure of the deformations of the sommitale zone led this morning also allowed a visual recognition of the activity. Some lava flows and a main eruptive vent remained active. As of the 4th of Jnanuary OVPLF reported that eruptive activity was continuing but with a reduced outflow.. Only lava fountains with small high and one active lava flow were visible. Tremor was slighly decreasing but remained stable. An aa lava flow covered about 90% of the 2008 flow on the floor of the Dolomieu crater. As of the 2nd of January, OVPLF reported that Piton de la Fournaise volcano erupted this day at 14:30 local time (GMT +4). The eruptive fissure is situated in the cliff around the Bory and Dolomieu summit craters. Some lava fountains tens of metres in height have been observed during a reconnaissance jointly carried out by the Gendarmerie Nationale (PGHM) and the Piton de la Fournaise Volcanological Observatory. During this reconnaissance, lava flows were observed flowing in the interior of Dolomieu crater. significant landslides and cliff collapses within Bory crater were also recorded. These collapses fuel eruption plumes of ash and gases that are rising above the summit craters of Piton de la Fournaise. This eruption was preceded over two hours by a seismic crisis commencing at 12:00 local time. A small plume of volcanic gas from the eruptive zone was already observed around 12:00. After some minutes of calm, an eruptive tremor appeared on the screens of the seismological network of the observatory at 14:25. PREVIOUS ERUPTION : As of the 15th of December, OVPLF reported that the Piton de la Fournaise volcano erupted Monday, December 14, 2009 at 18:45 (local time GMT +4). The eruption was preceded by a seismic crisis and a raise of the summit area deformations, which started at 17:30 (GMT +4). The eruptive tremor began at 18:30 (GMT+4). A system of sub-parallel fractures along the summit of Dolomieu crater fed lava flows on the southern slope of the Piton de la Fournaise, inside the Enclos Fouqué. A second fissures system opened on the eastern flank of the Dolomieu summit crater at 20:25 (GMT +4). Then lava flows were spent towards the eastern slope. This eruption ended during the night at 00h40 (GMT +4) after a gradual decrease in magma supply from midnight (local time). This morning, Tuesday, December 15, 2009, a visible degassing in the south and southeast fractures is associated with a low intensity eruptive tremor. All of the lava flows was confined to high zone of the volcano and more specifically the slopes south and south-east of Piton de la Fournaise. As of the 6th of November OVPLF reported that on November 5, an intense seismic swarm occurred between 7:30pm and 8:30pm (GMT +4) at about sea level, including an earthquake of 80 seconds. This crisis was followed by a 30 minutes aseismic phase and then by sustained tremor. The first vent opened at 8:50pm on the southern cliff inside the Dolomieu crater. At 9:05pm, a fracture propagated towards east on the upper south-eastern flank of Piton de la Fournaise feeding a first lava flow. A 9:20pm, a second fracture opened on the eastern volcano flank between 2450 and 2300m asl. The eruption was also recorded by the three webcams of the observatory, which, together with the deformation and tremor patterns, allowed a rapid identification of the eruption sites. The fractures fed strombolian activity, small (about 20 meters high) fountains and aa lava flows, which were visible from the national road lining the coast in the Grand Brûlé area. At 3:00am on November 6, the eruptive tremor declined to a very low intensity level. A first survey on the volcano summit at 7:30am confirmed that the lava fontaining was no longer active and the lava front had stopped at about 1900 m elevation. At 9:00am the eruptive tremor disappeared, thus confirming the end of the eruption. As of the 30th of October, OVPLF reported that the seismicity was still in light increase. A new seismic crisis occured on the morning of 03:00 to 06:00 (local time). The hypocentres are still localised under Dolomieu. Volcanologists of the Observatory noted a partial migration of the earthquakes and deformation towards the North (this could be due to injection of a dyke towards north). The level of alarm remains to 1. As of the 23rd of october OVPDLF reported that during the day before (22nd of October) 18 earthquakes occured, but no eruption started yet. As of the 21st of October,OVPDLF has reported that seismic activity indicates magma is probably within 500 m of the surface. A change in the chemistry of volcanic gases appeared for the first time yesterday since the outbreak of volcanic alert on the 4th of October. The whole of these observations clearly confirms the progression of the magma towards surface. An eruption thus remains possible in the short or medium term. The level of alarm remains to 1 for the moment. On 18 October, OVPDLF reported that another seismic crisis was noted along with deformation on the N and S sides of Dolomieu crater. Aerial observations on 19 October revealed a small new fumarole in the crater. Changes in the chemical composition of the gases were also noted. A greater number and duration of rockfalls than in previous days was detected on 20 October. As the the 17th of October (09:30 am)), OVPF reported that during past night (16th to 17th of October), the frequency and the intensity of the seismicity were in progressive increase. The trend of progressive deformation of the volcano was confirmed, in particular on the side the North of Dolomieu and close to the Dolomieu crater.Collapses of small volume inside Dolomieu were registered.No variation of the chemical composition of gases was noted. Previously, a new seismic crisis started on 14th of October at 8:09am (local time) and ended at 10:04am. This important seismicity was associated with weak ground deformation of the North flank of the Dolomieu. The day before 79 earthquakes have been recorded, mainly in the areas mentioned above. As of the 9th of October, The observatory of the Piton de la Fournaise reported that the seismic crisis that occured yesterday ended on 8th of October in the morning at 10:57 am. This seismicity was located beneath the volcano summit under craters Bory and Dolomieu. This phase has been associated with weak North flank deformation of the Dolomieu crater. No chemical variation in gas was noted. Previously, as of the 7th of October, the Institut de Physique du Globe de Paris from the Observatoire Volcanologique du Piton de la Fournaise (OVPDLF) reported that seismic activity increased on 7th of october in the morning from 8:30 am and since remained at high level. Not eruption occured yet, but local prefecture of the Reunion issued the alert level 1. Enclos Fouqué entrance has been closed . Yesterday 6th of october, 120 earthquakes were registred from the network accompanied with sligh ground deformation. Previous eruption started on 14th of December 11 PM (TU) ended on 4th of February at 8 PM (TU). On February 2nd, 21 earthquakes were recorded including one with mag. 2.2 accompanied with a decreasing of the volcanic tremor. As of the 3rd of February seismic activity increased again and tremor decreased. In the morning, only one lava flow was active on the Northwest side. Between 8-9th of January, two earthquakes located above the sea level were recorded (max = 1.5 mag). As of the 29th of December, OVPF scientists observed during a fieldwork the small lava pond which remained active with few lava ejection above the cone. Following an active episode during the past week-end with about 10 visible lava flows on the talus and some outpouring on the flow within the Dolomieu, the situation changed on Monday. Except from the active cone, no other glowing lava could be observed. Degassing remained relatively important, time to time, the Dolomieu was filled with bluish gaz emission. As of the 26th of December in the morning (9am), OVPF reported that eruptive tremor increased again (3 time more compared at the beginning of the eruption), but remained fluctuating. Following a fieldwork during the afternoon of 24th of December, volcanologist reported (5pm) that a small active lava pond formed within the small cone in the Dolomieu. Time to time, lava fountaining occurs. Many small lava flows are issued from small lava tubes around the main lava flow. GPS measurements did not showed inflation or deflation at the summit. OnThursday 18th of December, in the evening, the eruptive tremor increased but this day returned at the previous level, the same at the beginning of the eruption. As of the 17th of december SO2 output was estimated at about 1000 Tons/day. As of the 15th of december, OVPF reported that following a seismic crisis during Sunday (more than several hundred earthquakes), and an important seismicity during the night, a volcanic tremor, located beneath the summit, started at 2:45 am. An inspection carried out on 15th in the morning showed that two eruptive fissures were active within the Dolomieu crater, at half slope NNE and NE. The lava flow rate is very weak; the lava covered only 15-20% of the September 2008 lava. Also the SO2 output was very low. As of the 28th of November, OVPF reported that the volcanic tremor declined since the early morning, suggesting that the eruption was declining, with a phenomenon ‘Gaz Piston' (important gas bubbles with very few or not magma emission) making its appearence in the seismic record. From 2pm ( local time) "gas piston" phenomenon ended and this short eruptive phase ended. No seismic signal was recorded since this time. As of the 27th of November, according to a report of the OVPf, following a short seismic crisis between 1125am et 1140am, the volcanic tremor started at 1150am (local time). From the tremor map, this new eruption occured within the Dolomieu crater, probably at the same place of the previous activity during October 2008. A volcanic plume was visible in the West part of the Dolomieu. As of the 31st of October, a new OVPF Buletin reported that during the previous night a new seismic crisis occured between 4am and 440am with about 100 earthquakes accompanied with weak ground deformation recorded by the tiltmeter network. As of the 22nd of October, OVPF reported that 11 summital earthquakes were recorded this day (max. magnitude1,2). No deformation occured. As of the 20th of october, OVPF reported that in the morning, between 8AM et 10AM, a new seismic crisis occured. No other event was noted for the moment. As of the 17th of October OVPF reported that since 3 days ago seismic activity increased. This activity increased more on 16th of October beetween 630PM and 830PM (51 earthquakes) then re-decreased. Repartition of the earthquakes : 14th of October: 62 ; 15th of October: 59 ; 16th of October: 166; No long-term inflation was recorded for the moment. Previous activity : as of the 2nd of October OVPF reported that eruptive activity within the Dolomieu ended in the early morning. The tremor dropped from 410AM and totally disapeared at 445 AM (local time). Only a very weak deflation has been recorded during the eruption and for this reason, it's possible that other eruptive episode could occurs in the short term (days or weeks). Total lave volume of the eruption is about 850.000 m3 for 10 days of activity.As of the 27th of September OVPF reported that eruptive activity was still continuing in the Dolomieu. Volcanic tremor remained stable at a low level since the 26 september in the morning. Three summit low intensity earthquakes were recorded. No direct observation was possible due to the poor meteorological condition. Wednesday estimation of the size and volume with an aerial photography showed that the lava surface on the Dolomieu floor was about 180x100m (24 September in the morning) and a maximal thickness of 30m. The present volume has been estimated at about 300 000m3, an flow rate is 1m3/sec. As of the 21st of September, a special bulletin of the OVPF reported that following a short seismic crisis (about 10 earthquakes) a volcanic tremor appeared and the eruption started at about 330 PM. This new eruption occured in the West part of the Dolomieu (half hight) under the Bory crater. Several lava flows went down toward the floor of the Dolomieu and formed a small lava pond. As of the 17th of September , ovpf reported that important seismic activity is still continuing with 48 earthquakes recorded this day ( 41 with mag. < 1,0 ,   5 with mag. between 1,0 et 1,5 and  2 with mag. between 1,5 et 2,0) . Field observations confirmed an increase in degassing from the SW part of Dolomieu crater and the presence of hydrogen sulfide. Another seismic crisis was detected during 15-16 September. Numerous landslides followed the crisis, but may have also been associated with heavy rains. The Alert Level was not changed. As of the 12th of September, a preliminary bulletin from OVPF reported that since 1015AM (local time) this morning volcanic tremor started at the volcano and stayed until 1130AM. The tremor (weak and variable) is located beneath the summit of Dolomieu. According to an aerial observation during the end of the morning, no eruptive activity occured yet, but important SO2 emissions were noted. Another trémor (more high frequency) occured in the afternoon at 350 PM, but stopped around 8PM. During the day of the 12th of September, 30 earthquakes were recorded with a maximal magnitude = 1,6. According to OVPF scientists an eruption could be occurs within days or weeks. Alert level remains 1. As of the 9th of September, OVPF reported that an important seismic crisis occured during the night between 1123PM and 120 AM characterized by several hundred eartquakes. No deformation was recorded. On 3rd of September, 76 earthquakes were already recorded with a maximum magnitude 2.9 and 3.0. As of the 15th of August, OVPFalready reported that a seismic crisis (2h35 duration) occured this day between 5AM (local time) and 735AM (local time). This short crisis was accompanied with ground deformation in the Dolomieu area. At 10am, some superficial isolated earthquakes (about 500 m a.s.l.) still occured. Previously on 4th of August another short seismic crisis (10mn) already occured. Previous activity : as of 21st of June 2007, OVPF reported that from one week many earthquakes occured every day beneath the volcano (sometimes more than 100 per day). several of them occured under the sea. As of 21st of June, maximal magnitude was 2.6. As of the 2nd of May the Observatoire Volcanologique du Piton de la Fournaise, IPGP, reported that after one month of very high activity, the eruption at Piton de la Fournaise, which started on April 2nd in the Grand Brûlé at 650 m altitude, finally stopped on May 1st. The debit at certain moments was estimated between 100 and 200 m3 per second and the lava flows covered an area of about 4 km2, with up to 30 or 40 m thick lava. A platform of about 35000 m2 was build on the sea and first estimations of the erupted volume amount to 120 x 106 m3 , which ranges this eruption between one of the largest known historical eruptions at Piton de la Fournaise. As of the 27th of April the OVPF reported that the seismicity under the summit was reinforced. There were 50 seismic events the day before and the lava flows remained very abundant in the Grande Brulé. As of 21st of April, the latest OVPF report informed the the volcanic tremor remained at the same low level. Lava flows were still went down in the Grand Brulé from the vent located to 650 m elevation with important variations. As of the 20th of April the Observatoire Volcanologique du Piton de la Fournaise, IPGP that the collapse of Dolomieu crater was continuing. The tremor was on a very low level, the seismics under the summit of the Piton of Fournaise persisted. As of the 12th of April the Observatoire Volcanologique du Piton de la Fournaise, IPGP reported that members of the PC of St. Philippe observed two lava flows, the first going along the rampart, a second in the medium of cast in place, arriving at the sea. The inhabitants of the small village of Tremblet breathe better, the situation finally seems to still be improving. The crater which broke down on a 300 m height stabilizes slowly. As of the 7th of April, OVPF reported that following a fligh over the volcano on the morning, observation showed that a large part ot the Dolomieu crater floor collapsed on a surface estimated to 1000 x 700 m and a depth of about 300 m. The activity seismic remained at high level and many local collapse occurs. As of the 6th of April the OVPF, reported that the eruption at Piton de la Fournaise volcano continues and eruptive activity, lava fountains and lava flow emissions from the fissure vent at 600-500 m elevation, increases. Lava flows had already crossed the National Road in the afternoon of 2 April and the southernmost of the 3 principal lava flow branches reached the sea in the evening the same day. After decreasing for a while, an unusual increase in seismic activity has been observed since 3 April. It is marked by earthquakes below the summit of the volcano at altitudes between 0 and 500 m above sea level, similar to the ones registered before the opening of the fissure on 30 March SE of the summit. They are interpreted as consequence of internal collapse phenomena and might be preceding a collapse event similar or stronger than the one in 1986 when a 100 m deep pit crater was formed. At the same time, tremor (thought to be caused by the erupting magma moving along the conduit and the radial dike) has increased as well, accompanied by increasing visual effusive activity. In addition, a marked increase in sulphur dioxide emission has been noted. Inhabitants in the nearby city of St. Pierre have been suffering from "vog" - volcanic smog caused by clouds of aerosols rich in sulphur dioxide (SO2) emitted mainly at the eruptive vent and from the lava flows. Several people have been brought to hospital for treatment of skin and eye irriations as well as asthma caused by the gas whose concentration temporarily reached alarming levels, triggering the autorities to issue a general health warning for the island. Reports of a new eruptive fissure near the Pointe du Tremblet with its inhabited centres in the lower areas just outside of the Enclos turned out to be wrong. However, but scientists from the observatory don't exclude the possibility that a new fissure could open up at even lower elevation. Preparations for an emergency evacuation of this area have started since late of 4th of April. Access to the summit area of the volcano and the low elevation area near the lava flows from the side of St. Pierre has been restricted by authorities. As of the 2nd of April, OVPDLF reported that a new eruption started at 10 AM. A new eruptive fissure opened in the Southeast part of the enclos; the lower part of the fissure is located at 500 m a.s.l at the foot of the Rempart du Tremblet. The 1 km long eruptive fissure trend NO-SE- During the morning lava fountaining (50 m high) occured from the fissure. Associated lava flows went down fastly and about 2 PM the front was at 300 m of the RN2. On Wednesday 3rd of April eruption was still continuing. Lava flows crossed the road RN2 during the afternoon. As of 30th of March, OVPDLF reported that following a seismic crisis and deformation of the summit zone, a new eruption started on 30th of March ( 23 PM - local time) on the South-East flank of the volcano within the Enclos close to the Chateau Fort area. This short erutive phase ended on 31st of March at about 8 AM in the morning. (from OVPF-IPGP report) from OVPF-IPGP - (Thomas Staudacher, OVVPF) -(OVPF information d'après Journal de l'île de la Réunion - ). Live webcam - IPGP

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COMOROS - Karthala volcano

January 20th, 2007

As of 19th of January, Volcano observatory reported that on Thursday 18th the volcano shook twice again and local volcanologists said there was still a threat of eruption despite the tremor seems weakening. Comoros authorities have made emergency plan to help as many 30.000 people in case of eruption. As of 13th of January, volcano observatory reported that Mount Karthala (2631m) begun emitting fumes and producing a red glow over the tops. According to the chief geologist, the volcano has become eruptive since yesterday evening 12th of January. The lava level had risen in the volcano's crater. Preliminary information reported that residents of Mvurni, a town at 1000 m altitude on the volcano West slope were broken up by strong fumes. The island had been on red alert. The last big eruption of the volcano occured in April 2005, sent thousands fleeing in fear poisonous gas and lava. The worst disaster on record came in 1903, when 17 died from noxious fumes that seeped from cracks. The southernmost and largest of the two shield volcanoes forming Grand Comore Island (also known as Ngazidja Island), Karthala contains a 3 x 4 km summit caldera generated by repeated collapse

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TANZANIE - Lengai volcano

February 22nd, 2010

As of the 22nd of February GNN/GVP reported that periodic eruptions from a small fissure and steam emissions from an area of the crater rim next to a part that had collapsed were observed on 11 February, and three fresh black hornitos were noted on the W part of the crater floor, a cone-shaped grey hornito in the middle of the floor and a new black lava flow to the S were seen during 14-15 February. Previous Informations : June-August 2009: a few reports received during the summer, including ones documenting visits in August by Thomas Holden , in July by David Gregson , and in June by Tobias Fischer , indicate that Lengai continues to produce small effusive eruptions within the pit crater. Thomas Holden reported that on his climb in late August (exact date unknown) he saw active lava flows. Tobias Fischer witnessed flows and a small lava lake ~5m in diameter in June.  David Gregson did not see significant activity but heard sounds of activity at depth. Although the activity appears to have returned to the typical eruptions of fluid natrocarbonatite lava for which Lengai is so well known, no samples of the new flows have been obtained for analysis due to their inaccessability deep inside the pit crater.  It is not known how similar the new lava is in composition to the lavas produced prior to the 2007-2008 eruption. (From Fred Belton website)
Previous information : qccording to Frederick Belton team which climbed Ol Doinyo Lengai on 18 June 2009reported that the new active cone covered the former crater floor entirely except for an area N of the summit. The new cone's W, N, and E sides stood about 30 m above the rim of the former crater and enclosed a deep crater. The visitors saw a few small vents on the crater's floor. Frequent emissions of ash-poor plumes originated from the SW part of the crater's floor, producing light ashfall. They heard continuous loud rumbling noises, occasional gas-jetting sounds, and rockfalls. As of the 21st of February, the Global Volcanism Network (GVN) reported that Ol Doinyo Lengai volcano in Tanzania erupted on 19th of February, according to an aviation report. Ash was observed to 38,000 ft. Pilots have been advised to avoid flying near the volcano. The activity at Lengai seems to be increasing. In the past two weeks, explosions have ejected ash plumes rising several kilometers. On 15 Feb., Dutch pilots observed and photographed an eruption plume rising to estimated 12 km (36,000 ft). The Toulouse VAAC reported that an ash plume from Ol Doinyo Lengai was observed by pilots on 15 February and rose to an altitude of 11.6 km (38,000 ft) a.s.l. As of the 24th of January, the Global Volcanism Network (GVN) has reported that a visitor to Ol Doinyo Lengai informed that it erupted on 14 January. According to this visitor "shower of stones" fell at their location about 50 m from the summit and a lava flow went another direction. Typical ash eruption from the new ash cone in the N crater. A small group from Volcano Discovery , local mountain guides and partners stayed near and on Lengai volcano during 17-21 January. During this period, Lengai continued to erupt ash to several 100 metres above the new ash cone during phases lasting several hours alternating with periods of quiet when only a weak plume of very fine gray ash and gas was issuing out of the new ash cone. Photos from an eruptive phase of Ol Doinyo Lengai volcano consisting in near continuous ash emissions from its new crater and taken from the summit during a recent expedition in January 2008 have been posted at the Discovery: http://www.volcanodiscovery.com/volcano-tours/photos/lengai/0108.html . These photos also document the impressive recent changes on the volcano and help to illustrate the significant hazards present when climbing Lengai or staying at its top. The Toulouse VAAC reported previously that an ash plume from Ol Doinyo Lengai was observed by visiting scientists on 20 December and rose to an unreported altitude. As of the 20th of October, John Seach has reported that a pilot report indicated an eruption of Ol Doinyo Lengai volcano in Tanzania occurred at 0830hrs local time today. An ash plume reached 25,000 ft. altitude, and was visible from a distance of 50 miles. The eruption lasted 30 minutes. As of the 7th of September, according to Matthieu Kervyn De Meerendre, University of Gent (Belgium) has reported that Ol Doinyo Lengai has re-erupted again. A large eruption (?) seems to be taking place at Lengai volcano, this time for real On 4 September 2007, reports started coming in that a large (natrocarbonatite) lava flow is descending the West flank. A considerable ash plume was visible on satellite data. Over 30 thermal anomalies have been detected by the MODIS team since August 23 - more than during the large eruption in March 2006. On 4 and 5 Sep, the thermal anomaly at the summit was extremely strong. From this and satellite imaginery, it seems that there was a short overflow to the East and a major overflow to the West starting on September 1st (it could be a bush fire on the volcano flank ignited by lava). New overflows on 5 Sep seem to be taking place on the W and NW flanks. The symmetrical Ol Doinyo Lengai stratovolcano is the only volcano known to have erupted carbonatite tephras and lavas in historical time. The prominent volcano, known to the Maasai as "The Mountain of God," rises abruptly above the broad plain south of Lake Natron in the Gregory Rift Valley. The depth and morphology of the northern crater have changed dramatically during the course of historical eruptions, ranging from steep craters walls about 200 m deep in the mid-20th century to shallow platforms mostly filling the crater. Long-term lava effusion in the summit crater beginning in 1983 had by the turn of the century mostly filled the northern crater; by late 1998 lava had begun overflowing the crater rim.

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CONGO - Nyamulagira volcano

January 28th, 2012

As of the 28th of January, MODVOLC is still recording thermal anomaly on the volcano and probably the eruptive activity is still going on. (photos from M.Rietze).The initial scoria cone appeared inactive and second cone formed to the N of the first cone. Both cones were about 300 m high. The second cone was extremely active during the duration of the observations (about 15 hours) with fire fountains over twice the height of the cone; lava flowed N. The observers, about 1.5 km away, felt the heat from the eruption as well as lapilli fall. The VolcanoDiscovery Team observed the fissure eruption at Nyamuragira that began on 6 November 2011 during 22-25 January 2012 from the newly formed cinder cones located about 10 km E of the summit crater. They reported three coalescent cones with the largest cone containing a small lava lake. The lake ejected spatter every few seconds as high as 200 m above the summit; individual bombs reached the base of the cone. Lava flows from the vent extended several kilometers N. Numerous small breakouts formed secondary flows, and a large breakout about 2 km N of the cone fed a large lava flow about 20 m wide. Burning forests were reported to the NNE. Satellite imagery acquired on 3 January from the Advanced Land Imager (ALI) on NASA's EO-1 satellite showed an active lava flow to the NE of the central vent over the fissure located 11-12 km ENE of Nyamuragira's main crater. A sulfur dioxide-rich plume was also detected.According to OMI data, SO2 plume is still rose above of the volcano suggesting tha the eruption is continued. As of the 8th of December, the eruptive activity is still continuing. Thermal anomaly and gas plume are still visible from satellite image. On 18 November, Virunga National Park reported that lava flows from the eruption along a fissure 11-12 km ENE of Nyamuragira's main crater had possibly stalled. An observer aboard an overflight a few days before noted that the lava did not appear to have moved any further N. A photo taken from the Rumangabo headquarters (7.5 km NE of the eruption site) on 16 November showed a tall cinder cone with lava fountains rising above the rim. The eruption at Nyamuragira that began on 6 November, after two days of intense seismic activity, was located along a fissure 11-12 km ENE of the main crater, close to one of the 1989 eruption sites. Virunga National Park staff had previously been observing the eruption from a hilltop in Rumangabo, but on 9 November the staff and rangers traveled to the site. After a 3-hour hike, the team viewed the eruption from the S and noted roaring and lava fountains, as well as thunder and lightning. The observers also noted that the ground was covered by black pumice. On 11 November about 100 people, including staff, rangers, carpenters, porters, and volcanologists, traveled to a similar but safer location to set up a camp for visitors. The eruption site was described as a flat area with a 500-1,000-m-long fissure, oriented perpendicular to the Albertine (Western) rift. Lava fountains rose as high as 300 m above a cinder cone. Slow-moving lava traveled N. GORISK noted that radar images acquired on 11 November showed the largest deformation ever detected by the method (InSAR) since the early 1990's over Nyamuragira. A very preliminary analysis of the observed deformation suggested an affected area of more than 250 square kilometers. The ground rose more than 50 cm at the eruptive site where the spatter cone was developing. Another 15 cm of deformation was detected within the Nyamuragira caldera accompanied by deflation on the flanks. Satellite images acquired on 12 November showed that the lava flow had traveled approximately 11.5 km during the six days of the eruption. As of the 15th of November, The eruptive activity was still continuing characterized by lava fountain about 300 m high and lava which overflowed on the North flank of the volcano.(video) .As of the 7th of November, Rangers from the Virunga National Park reported that an eruption began last night on Nyamuragira in the Democratic Republic of Congo in central Africa. The eruption was observed from the park headquarters and it was reported that it appears to be a flank eruption. Africa's most active volcano, Nyamuragira (Also spelled Nyamulagira) is a massive basaltic shield volcano N of Lake Kivu and NW of Nyiragongo volcano. Lava flows from Nyamuragira cover 1,500 sq km of the East African Rift. The 3058-m-high summit is truncated by a small 2 x 2.3 km summit caldera that has walls up to about 100 m high. About 40 historical eruptions have occurred since the mid-19th century within the summit caldera and from numerous fissures and cinder cones on the volcano's flanks. A lava lake in the summit crater, active since at least 1921, drained in 1938. Twentieth-century flank lava flows extend more than 30 km from the summit, reaching as far as Lake Kivu.

CONGO - Nyiragongo

November 16th, 2011

According to NASA's Earth Observatory, a satellite image of Nyiragongo acquired on 15 November showed heat coming from the active lava lake in the summit crater. Previous news : The Toulouse VAAC reported that during 4-5 February 2011diffuse plumes, likely composed primarily of sulfur dioxide gas, were observed in satellite imagery. One of Africa's most notable volcanoes, Nyiragongo contained an active lava lake in its deep summit crater that drained catastrophically through its outer flanks in 1977. In contrast to the low profile of its neighboring shield volcano, Nyamuragira, Nyiragongo displays the steep slopes of a stratovolcano. Benches in the steep-walled, 1.2-km-wide summit crater mark the levels of former lava lakes, which have been observed since the late 19th century. About 100 parasitic cones are located on the volcano's flanks and along a NE-SW zone extending as far as Lake Kivu. Monitoring is done from a small observatory building located in Goma, ~18 km S of the Nyiragongo crater. (From GVO) - Nyiragongo Photos gallery - January 2011 (German group)
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YEMEN - Jebel Zubaïr archipelago

January 15th, 2012

As of the 15th of January, EO-1 satellite image do not shows any volcanic activity on Jebel Zubaïr archipelago. The volcanic eruption in the Red Sea appears to have stopped, leaving behind a newborn island A satellite image acquired on 7 January showed the newly-formed island in the northern part of the Zubair Group. The island had grown to about 530 x 710 m, and a gas-and-steam plume containing ash rose from a distinct cone. As of the 30th of December, the eruptive activcity is still continuing (MODIS IMAGE). An eruption from the northern part of the Zubair Group continued during 21-27 December. MODIS imagery from NASA's satellites on 22 December showed a plume, possibly containing ash, rising from what was thought to be a submarine eruption. Imagery acquired on 23 December from the Advanced Land Imager (ALI) on NASA's EO-1 satellite showed a new island at the location with a plume rising from it, roughly 500 m N of Rugged Island and more than 500 m in diameter. The island was not present in a similar image acquired on 24 October 2007. As of the 22nd of December 2011, according to several informations, a volcanic activity occured off the coast of Yemen, probably from North part of Jebel Zubair volcano islands (Red Sea). However, there is still not a lot of information out there on this eruption. It seems that the eruption started on 19th of December, following a seismic crisis. On 19 and 20th of December a vapor plume was visible from the MODIS satellite images and OMI data revealed SO2 emisions. MODIS imagery from 20 December shows a plume rising from a submarine eruption about 1.5 km SW of Haycock and N of Rugged (near the N end of the Az-Zubair island group), and about 12 km NE of Jebel Zubair island. A bathymetric sketch map made in 1973 indicates a water depth of about 100 m in that area. New Modis image taken on 22nd of December shows clearly a volcanic plume Northwest of the Jebel Zubaïr extending 10 km to the North. A green discoloration was visible on the sea surface located East of the Jebel Zubaïr archipelago suggesting a submarine activity (?). The 5-km-long Jebel Zubair Island is the largest of a group of 10 small islands and submerged shoals that rise from a shallow platform in the Red Sea rift. The platform and eruptive vents forming the islands and shoals of the Zubair Group are oriented NNW-SSE, parallel to the rift. An early explosive phase was followed by a brief period of marine erosion, and then by renewed explosive activity accompanied by the extrusion of basaltic pahoehoe lava flows. This latest phase of activity occurred on the morphologically youngest islands of Zubair, Centre Peak, Saba, and Haycock. Historical explosive activity was reported from Saddle Island in the 19th century. Spatter cones and pyroclastic cones were erupted along fissures that form the low spine of Zubair Island.

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ERITREA - Nabro volcano

September 29th, 2011

According to NASA's Earth Observatory, satellite images of Nabro acquired on 28 September showed heat from the vent in the central crater, and from an area 1.3 km S of the vent that indicated an active lava flow. A small and diffuse plume rose from the vent. A region of seemingly thicker black ash(that completely covered the sparse vegetation) was noted S of the crater and thinner layers of ash (with some areas of visible vegetation) flanked either side of the region. As of the 26th of July, OGA reported that an earquakes mag. 3.1 occured near the volcano site. Some thermal anomalies are still detected by MODIS. Previously, based on analyses of satellite imagery, the Toulouse VAAC reported that on 16 July an ash plume from Nabro rose to altitudes below 5.5 km (18,000 ft) a.s.l. A weak eruption detected on 17 July decreased through the day then appeared to have stopped. As of the 4th of July, OMI reported that a rich SO2 volcanic plume was still visible from MODIS image taken at 8:00 TU issuing from thermal anomaly. The VAAC of Toulouse in France also reported ash plume the day before between 6PM and 10PM art about 6km high. As of the 1st of July, OGA reported that no seismic activity detected in the Nabro volcano vicinity. Small plume is still rose above the volcano. Two earthquakes occured in the Gulf of Tadjoura. As of the 30th of June, OGA reported that two eartquakes occured in the vicinity area of the Nabro volcano. The eruptive tremor is no longer detected since two days (image with detailed look 29th of June). In the morning 6.00 TU a volcanic plume still rose to about 4500 m above the volcano. (new satellite image 27th of June). During 22-26 June large amounts of sulfur dioxide in the region continued to be detected by satellite images. Based on analyses of satellite imagery, the Toulouse VAAC reported that during 26-27 June plumes rose to altitudes up to 6.1 km (20,000 ft) a.s.l. As of the 23rd of June OGA reported that few earthquakes of low magnitudes were detected during the past hours. an ASTER image from TERRA satellite showed a 15 km long lava flows travelling NW emitted from the breach in the caldera wall toward the South. A high-altitude plume, likely rich in water vapor, rose from the erupting vents and a diffuse ash-rich plume drifted SW. The eruptive tremor is sill being high. Now, the eruptive plume (mainly SO2 content) covered a very long and large zone in Africa and middle East countries. As of the 21st of June, OGA reported that few earthquakes occured this day. The tremor activity decreased. As of the 18th of June,OGA reported that few earthquakes were recorded on Saturday morning. Slight recovery of the tremor activity occured yesterday after 20.00 UTC. Modis image showed a thermal anomaly at 7:45 TU yesterday in the morning (maybe a lava flow ?). After a short break during yesterday morning 17th of June, a new seismic phase started at 9:16 TU with an earthquake mag MI=5.8 that occured at 11:00 TU. As of the 16th of June, end of the afternoon, no plume was visible from the different satellite images. OGA reported a progressive decrease of the tremor activity from 4.00 UTC and remain barely visible after 10:00 UTC. As of the 14th of June, VAAC reported that Nabro erupted for a third day on Tuesday but with reduced intensity, its ash cloud spreading out over Sudan and toward Saudi Arabia and forcing the cancellation of some regional flights. The Toulouse VAAC reported that an eruption from Nabro (originally attributed to Dubbi) started between 0000 and 0200 on 13 June. An eruption plume initially rose to altitudes of 9.1-13.7 km (30,000-45,000 ft) a.s.l. then was later detected at altitudes of 6.1-10.7 km (20,000-35,000 ft) a.s.l. during 13-14 June. According to the Eritrean Ministry of Information, ashfall covered hundreds of kilometers and the government evacuated area residents. Witnesses noted that the eruption had started at about 2100 on 13 June. Satellite images that same day showed the plume drifting more than 1,000 km NW, over parts of Sudan. On 14 June a detached ash cloud was detected over southern Israel according to news articles. A plume from Nabro was not obvious on satellite imagery. As of the 13th of June 2011, the Vaac reported that the Nabro volcano in Eritrea erupted and sent a plume of ash up to 15 kilometres into the air on Monday, disrupting air traffic in the region. The eruption was preceded by seven moderate earthquakes yesterday afternoon. A 5.6 magnitude quake at 21.03 GMT signalled the start of the eruption. The quake was centred 48 km south of the town of  Edd (pop 11,259) and 199 km southwest of the city of Al-h'udaydah (pop 617,871). A 4.6 magnitude quake followed less than 35 minutes later. According to Meteo France (Vaac's operation for Southern Europe and Africa the eruption, which took place at 2100 GMT on Sunday, is "seems relatively important."Based on satellite images the volcanic ash is reaching altitudes of 13 to 15 kilometers.The eruption, which was continuing late Monday.. According to preliminary Meteo-France simulations, the lower-density ash clouds were heading west/northwest toward Sudan, while the higher-density clouds were heading west/southwest. If the cloud reaches Egypt, Israel or the Arab peninsula, the impact on air traffic will be more significant. On Monday afternoon officials in Ethiopia warned citizens to protect themselves from the ash and smoke coming from the volcanic eruption. Ash is falling on the northern Ethiopian town of Mekele. Asamara, the capital city of Eritrea, was also affected by ash from the erupting volcano. Nabro stratovolcano is the highest volcano in the Danakil depression of northern Ethiopia and Eritrea. Located at the SE end of the Danakil Alps, Nabro lies in the Danakil horst. Nabro is the most prominent and NE-most of three volcanoes with large summit calderas aligned in a NE-SW direction SW of Dubbi volcano. These three volcanoes, along with Sork Ale volcano, collectively comprise the Bidu volcanic complex. The complex Nabro stratovolcano is truncated by nested calderas, 8 and 5 km in diameter. The larger caldera is widely breached to the SW. Nabro was constructed primarily of trachytic lava flows and pyroclastics. Post-caldera rhyolitic obsidian domes and basaltic lava flows were erupted inside the caldera and on its flanks. Some very recent lava flows were erupted from NNW-trending fissures transverse to the trend of the Nabro volcanic range. GVN/GVP

ETHIOPIA - Erta Ale volcano

March 6th, 2010

As of the 5th of March 2010, according to Rafael Werndli reports an unusually hight lava level in the pit crater on Erta Ale in mid February 2010. The lake surface was approximately 20m below the pit's edge. The lava lake had a diameter of 100 to 110m. Occesional floodings of the uppermost terrace were observed. In addition a hornito was active in the north crater, ejecting scoriae and small lava flows. PREVIOUS INFORMATION AND REPORTS : As of the 20th of February 2008, the Stromboli-On-Line website has reported that upon their return to volcano Erta Ale, they found it to be in eruption on the 8th of February and have confirmed this information. Volcanologique de Geneve (SVG) trip on 8-9 February 2008 noted extensions of ropy lava in the N crater. The lake was little changed from the group's last visit in 2005. The group visited the N Crater, and, given its constant degassing, was able to take gas samples. They also measured the lake's surface temperature (700°C). The descent into this crater, seemingly easy, was made difficult by a mantle of very unstable lava scoria. An elevated level of the lava lake halted a subsequent descent.Previous information reported that on 7th of October 2005, according to Ethiopian newspaper an earthquake measuring 4.2 on the Richter scale, jolted northern Ethiopia (Teru area in Afar) on Tuesday triggering eruption of the Erta Ale. According to M; Manahlo Belachew, an expert in the seismology department of Addis Ababa University, the quake which strick the remote region afar is the 11th tremblor to rumble across the region since last month. As of 5th of October a hot spot was visible on the Erta Ale from the MODIS images which could confirmed an eruptive activty this day. Previous new report about recent activity of the Erta Ale : group of scientists assessed the visible changes at Erta Ale on 26 September after activity began around 24 September. In comparison to observations made in November 2004, they found that the southern main crater/pit had widened significantly, with portions of the previous crater walls having collapsed into the lava lake. A new cone-shaped construct had grown within the southern main crater where there had been a platform. A lava lake occupied the entire width of the inner crater/pit. In the northern crater/pit, there was a solidified lava bulge and abundant “smoking” along the crater walls. No incandescent lava was visible in the pit. Based on descriptions by local residents of seeing “red and glowing light shooting and rising into the air above the volcano,” the scientists believe that a Strombolian eruption probably occurred, emitting a significant volume of fresh magma within, and possibly out of, the pit. As of 4th of 0ctober, Personal source reported from Addis Ababa University that the recent earthquake that occured in Afar state has caused landslide and big fissure in Teru locality kebele 02 of the state near the active volcano Mount Erta Ale, a team of geologists who have just returned from the site disclosed. The earthquake observed from September 10 -24, 2005 is the culmination of volcanic activities in the area since millions of years ago, geologists Dr. Derge Ayalew and Dr. Gezahegn Yirgu told WIC. The geologists said the landslide and fissure are indicators that there would be a possible volcanic eruption in the future. The Physical Observatory of the Addis Ababa University recorded on Sunday earthquake that measured 5.5 on Richter scale following earthquake. In Erta Ale the volume of material inside the Crater is actually increasing i.e. rising up to the Crator rim. Due to all this recent geological activity the government is starting to evacuate the people residing around these areas. Previous Erta Ale visit : an international team led by SVE carried out a new visit at the Erta Ale from 22nd of January to 23rd of January 2005. During these two full days at the summit the eruptive activity showed no significant change since our previous observation carried out in November 2005. Degassing activity was still occuring from 3 of the 4 coalescents hornitos located in the SW part of the South crater, but decreased slightly in comparison with our December observations. There were about 10 m high and represented the only portion of the lava crust covering the crater floor where gas emissions were in evidence. One of the hornitos contained glowing molten lava visible from a window located in the upper part. During the clear day of Sunday 23rd of January, members of the team abseiled down within the crater to collect recent lava poured out from the hornitos during partial collapse. Degassing activity (mainly SO2) from the North crater has also slightly decreased in comparison with early December 2004. From a small terrace located in the NW part of the crater it was possible to observe the degassing activity from several hornitos ( some of them were several meters high in the central part of the " lava bulge ") - Near the NW wall of the crater two small red glowing areas were visible at the summit of two other hornitos. Seismic activity of the volcano, together with infrasound signals were recorded by a portable system of the University of Hamburg. Preliminary results of this deployment will be reported soon at this place. Informations : Henry Gaudru, SVE Geneva ; Alexander Gerst , University of Hamburg, Germany ; Georges Kourounis, Derek Tessier, Brian Fletcher (Toronto - Canada) , Motomaro Shirao (Tokyo- Japan) . A previous visit of the SVE-SVG group (4th of December 2004) have permits to observe an important change in the activity of the volcano. The lava lake activity stopped within the South pit crater and a solidified lava crust has filled the whole part of the crater floor (about 15 m below the crater rim). Three (4) coalescent hornitos (about ten meters high) have built on the solidified lava crust in the SE part of the South crater. During the night between 4th of 5th of December, some incandescent degassing lava was visible at the summit of two hornitos. Moreover, we have also noted that a new activity has recently occured within the North crater. A solidified lava bulge uplifted and filled more than 4/5 of the crater floor (about 20-25 below the crater rim). Strong and noisy degassing activity was occcuring in the central part of the lava bulge from several small hornitos. From the smell and bluish color, these gases contained a high quantity of SO2. During the night , ten small incandescent vents were visible at the periphery of the lava bulge. In the morning, two plumes rose above the volcano. Information : Henry Gaudru (SVE) and Co (SVG) - Erta Ale report in case of problem with this link look directly at "articles page" Recent Erta Ale photos 2011

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PHILIPPINES - Mayon Volcano

September 13th, 2011

As of the 13th of September, PHIVOLCS reported that Mayon Volcano's seismic network detected one (1) rockfall-related event during the past 24 hours.  Visual observation was not possible due to thick clouds covering the summit. As of the 2nd of September, PHIVOLCS reported that weak to moderate emission of white steam that crept downslope towards northeast and north-northeast could be observed from the crater visible yesterday morning.  Faint crater glow (Intensity 1- seen on telescope) was observed last night.  Ground deformation survey (precise leveling) conducted last 21 - 25 August 2011 indicated a slight inflation of the edifice as compared with 31 May - 04 June 2011. Mayon Volcano's seismic network detected one (1) volcanic earthquake and one (1) rockfall event during the past 24 hours. During cloud breaks moderate emission of white steam clouds was observed creeping down the northeast slope of the crater. Night observation was not possible due to thick clouds that covered the summit. As of the 6th of July, PHIVOLCS reported that Mayon Volcano's seismic network did not detect any volcanic earthquake during the past 24 hours.  Moderate  emission of white steam clouds drifting southwest and creeping down slope towards north-northeast was observed from the summit crater.  Night observation was not possible due to thick clouds covering the summit. Results of ground deformation measurement (precise leveling) conducted last 31 May 2011 to 04 June 2011 showed slight inflation of the volcano's edifice as compared with 06-10 March survey. PHIVOLCS reported that a deformation survey of Mayon conducted during 31 May-4 June showed slight inflation since a 6-10 March survey. White steam emitted from the summit crater during 8-13 June crept down the NW and WNW flanks. Incandescence from the crater was also observed. The Alert Level remained at 1 and the public was reminded not to enter the 6-km-radius Permanent Danger Zone (PDZ). Mayon Volcano's seismic network recorded two (2) volcanic earthquakes during the past 24 hours. During cloud breaks from 6:01 A.M. - 9:50 A.M. and 3:25 P.M. – 5:10 P.M. yesterday, steaming activity at the crater was moderate with white steam clouds drifting towards southwest. Crater glow was not observed due to thick clouds covering the summit last night. Measurement of sulphur dioxide (SO 2 ) flux yesterday yielded a value of 598 tonnes/day. Results of ground deformation measurement (precise leveling) conducted last 07-11 May, 2011 showed slight inflation of the volcano's edifice as compared with 06-10 March survey. As of the 25th of May, PHIVOLCS reported thatA marked increase in seismic activity was manifested by Mayon Volcano during the past 24 hours. The seismic network detected thirty-eight (38) volcanic earthquakes. During cloud breaks from 6:01 A.M. - 9:20 A.M., 2:35 P.M. - 2:55 P.M. and 4:35 P.M. – 5:29 P.M. yesterday, steaming activity at the crater varied from weak to moderate with white steam clouds drifting towards southwest.  Fair crater glow (Intensity II - can be seen by the naked eye) was observed from 8:47 P.M. yesterday to 4:40 A.M. today. Results of ground deformation measurement (precise leveling) conducted last 07-11 May, 2011 showed slight inflation of the volcano's edifice as compared with 06-10 March survey. As of the 13th of May, PHIVOLCS reported that Mayon Volcano's seismic network recorded twelve (12) volcanic earthquakes and three (3) rockfall related events during the past 24 hours. Steaming activity was weak to moderate with white steam drifting to various directions. Crater glow was observed at Intensity II (can be seen by the naked eye) last night.  Sulfur dioxide was measured at 745 tonnes/day. Results of ground deformation measurement (precise leveling) conducted last 07-11 May, 2011 showed slight inflation of volcano edifice as compared with 06-10 March survey. As of the 25th of April, PHIVOLCS reported that the seismic network around Mayon Volcano's recorded four (4) volcanic earthquakes and one (1) rockfall related event during the past 24 hours. Weak steaming was observed drifting west-southwest. Intensity II crater glow was observed last night. Results of precise leveling survey conducted last 06-10 March 2011 showed slight deflation of volcano edifice as compared with 05-10 January 2010 baseline survey. The seismic network around Mayon Volcano recorded one (1) volcanic earthquake during the past 24 hours.  Steaming was observed to be weak, white and creeping downslope towards the west southwest. Crater glow was observed at Intensity II last night.  Results of precise leveling survey conducted last 06-10 March 2011 showed slight deflation of volcano edifice as compared with 05-10 January 2010 baseline survey. Mayon Volcano's seismic network detected two (2) rockfall related events during the past 24 hours.  Steam emission varied from wispy to moderate and drifted towards the southwest direction. Fair crater glow (Intensity II – can be seen by naked eye) was observed last night.  Results of precise leveling survey conducted last 06-10 March 2011 showed slight deflation of volcano edifice as compared with 05-10 January 2010 baseline survey. The seismic network around Mayon Volcano did not record any volcanic earthquake during the past 24 hours. Steaming activity and crater glow were not observed due to thick clouds that covered the entire summit during the past observation period. R esult of ground deformation survey (precise leveling) conducted last 6-10 March 2011 showed deflation of volcano edifice as compared with 05-10 January 2010 baseline survey. As of the 1st of March, PHIVOLCS reported that The seismic network around Mayon Volcano recorded two (2) rockfall events du ring the past 24 hours. Crateral steaming activity and crater glow were not observed because thick clouds covered the entire volcano summit during the past observation period. R esults of ground deformation survey conducted in early February showed that the volcanic edifice remained inflated based from 2007 baseline data (Lidong Precise Leveling Line). As of the 12th of February, PHIVOLCS reported that seismic network at Mayon Volcano detected one (1) volcanic earthquake and four (4) rockfall events during the past 24 hours. Steaming activity varied from weak to moderate emission of white steam drifting towards the WNW direction.  Fair crater glow (Intensity II- seen by naked eye) was observed last night. Results of ground deformation survey conducted on 02-03 February 2011 showed that the volcanic edifice remained inflated based from 2007 baseline data (Lidong Precise Leveling Line). As of the 5th of February, PHIVOLCS reported that seismic network detected one (1) rockfall event during the past 24 hours. Steaming activity was moderate and crater glow was not observed due to thick clouds covering the volcano's summit last night and up to early this morning. Results of ground deformation survey conducted on 02-03 February 2011 showed that the volcanic edifice remained inflated based from 2007 baseline data (Lidong Precise Leveling Line). As of the 27th of January, PHIVOLCS reportred that the seismic network detected one (1) volcanic earthquake during the past 24 hours. Moderate emission of white steam was observed during cloud breaks. Crater glow was not observed due to thick clouds covering the summit all night. As of the 24th of January, PHIVOLCS reported that seismic network recorded two (2) volcanic earthquakes for the past 24 hours. White steam emission from the crater ranged from weak to moderate during the same observation period.  Fair crater glow (Intensity II – seen with naked eye) was observed last night. Results of ground deformation surveys conducted last November and December 2010 showed that the volcanic edifice remains inflated based on 2008 baseline data. As of the 21st of January, PHIVOLCS reported that seismic network recorded one (1) volcanic earthquake during the past 24 hours. During cloud breaks, steaming activity at the crater was at a moderate level. Fair crater glow (Intensity II – seen with naked eye) was observed last night. Results of ground deformation surveys conducted last November and December 2010 showed that the volcanic edifice remains inflated based on 2008 baseline data. As of the 16th of January 2011, the seismic network at Mayon Volcano recorded one (1) rockfall event during the past 24 hours. Steam emission was white and moderate while crater glow was not observed due to thick clouds covering the summit.  Results of ground deformation surveys conducted last November and December 2010 showed that the volcanic edifice remains inflated based on 2008 baseline data. Mayon, a 2463-metre stratovolcano, is famous for the near-perfect symmetry of its cone, as well as its ability to unleash destructive eruptions, with hazards including pyroclastic flows, lahars and heavy ashfall. Particularly violent eruptions causing many deaths occurred in 1814 and 1897; more recently an eruption in September 1984 caused no fatalities after warnings from Philvolcs brought about the evacuation of more than 70,000 people from at-risk areas near the volcano. Information : PHIVOLCS - Latest satelllite image of the Mayon (every 30 mn)

PHILIPPINES - Taal volcano

September 23rd, 2011

Taal Volcano's seismic network detected seven (7) volcanic earthquakes during the past 24 hours. Two of these events which occurred at 6:34 P.M. and 7:30 P.M. last night were felt at Intensity II by residents at Barangay Calauit in the southeastern part of the Volcano Island. Field measurements on 20 September 2011 at the eastern sector of the Main Crater Lake yielded slightly increased water temperature of 33.6 ° C from 33.5 ° C, water level at a steady 1.74 meters and more acidic pH of 2.72 from 2.79 as compared to previous readings. Field measurements on 06 September 2011 at the eastern sector of the Main Crater Lake yielded slightly increased water temperature of 33.5 ° C from 33.4 ° C and water level increase of 1.74 meters from 1.65 meters as compared to previous readings. Ground deformation survey (precise leveling) on the Volcano Island last 21-28 July 2011 indicated that the volcano edifice is slightly deflated compared with 01-10 June 2011, but is nonetheless still inflated compared with baseline data. Baselines calculated from continuous GPS (Global Positioning System) data for the period February to July 2011 also recorded a very slight but steady inflation of the northeast flank of the Volcano Island. Carbon dioxide (CO 2 ) emission recorded on 27 June 2011 at the Main Crater Lake was 1,821 tonnes/day, which is above background levels. Field measurements on 30 August 2011 at the western sector of the Main Crater Lake yielded slightly decreased water temperature of 32.9 ° C from 33.6 ° C and water level increase of 1.29 meters from 1.20 meters as compared to previous readings.  Field measurements conducted last 26 July 2011 at the eastern sector of the Main Crater Lake showed that the water temperature remained unchanged at 33.4 ° C, the water level increased from 0.86 meter to 0.91 meter and the pH value showed insignificant change from 2.85 to 2.86 as compared with the previous readings on 12 July 2011.  Minimal bubbling activity was observed at the middle portion of the Main Crater Lake. Measurements conducted last 19 July 2011 at the western sector of the Main Crater Lake showed that the water temperature changed slightly from 33.4 ° C to 33.0°C. The water level decreased from 0.85 meter to 0.81 meter and the pH value became less acidic from 2.80 to 2.91. Minimal bubbling activity was observed at the middle portion of the Main Crater Lake.  Results of the ground deformation survey (precise leveling) conducted around the Volcano Island last 01 - 10 June 2011 showed that the volcano edifice is slightly inflated relative to 26 April - 03 May 2011 survey.  Measurement of carbon dioxide (CO2) emission rate last 27 June 2011 at Taal Main Crater Lake yielded a value of 1,821 tonnes per day which is above the background level. As of the 18th of July, PHIVOLCS reported that seismic network recorded five (5) volcanic earthquakes during the past 24 hours. One (1) of these events was felt at Intensity II at Calauit, a barangay located at the eastern sector of the volcano. Field measurements conducted last 12 July 2011 at the eastern sector of the Main Crater Lake showed that the water temperature changed slightly from 33.4 ° C to 33.6°C. The water level increased from 0.74 meter to 0.86 meter and the pH value became less acidic from 2.74 to 2.85.  Minimal bubbling activity was observed at the middle portion of the Main Crater Lake. Results of the ground deformation survey (precise leveling) conducted around the Volcano Island last 01 - 10 June 2011 showed that the volcano edifice is slightly inflated relative to 26 April - 03 May 2011 survey.  Measurement of carbon dioxide (CO2) emission rate last 27 June 2011 at Taal Main Crater Lake yielded a value of 1,821 tonnes per day which is above the background level. Taal Volcano's status remains at Alert Level 1. As of the 5th of July. PHIVOLCS reported that Eleven (11) weeks after Taal Volcano's alert status was raised from Level 1 to Level 2 on 09 April 2011, the following monitoring parameters have been observed: 1.  The number of volcanic earthquakes recorded daily gradually declined to low levels beginning 1 st week of June 2011. From June 2 to 5, four (4) to eight (8) volcanic earthquakes were detected per day. Since June 6 to present, the number of recorded volcanic earthquakes further decreased to a daily count of zero (0) to six (6) small events. No perceptible volcanic earthquake has occurred since 02 June. 2.   Hydrothermal and steaming activities in the northern and northeast sides of the Main Crater and Daang Kastila area have abated.  Since 01 June 2011, the Main Crater Lake temperature remained at 32.5 ° C to 33.4 ° C, and despite becoming more acidic, measured pH of 2.78 – 2.59 vary around the baseline level of pH above 2.5.  All other geochemical parameters are returning to background levels. Bubbling activity at the northeastern sector of Main Crater Lake weakened and the activity has ceased in some of the bubbling sites. 3.   Ground temperature and total magnetic field measurements at Daang Kastila and in the Main Crater showed no significant changes in both parameters. 4.  Carbon Dioxide (CO 2 ) gas measurements at the Main Crater Lake since March 2011 showed a decreasing trend. From an elevated value of 4,670 tonnes per day (t/d) in March, CO 2 decreased to 2,057 t/d in May and then to 1,821 t/d in June. 5.  Precise leveling in June 2011 along the flanks of Volcano Island and Global Positioning System (GPS) data from November 2010 to June showed that the volcano is slightly inflated.  Ground deformation data, nonetheless, are not suggestive of large pressure build-up within the volcano edifice. The above observations suggest that Taal Volcano's activity has declined. In view thereof, PHIVOLCS is now lowering the status of the volcano from Alert Level 2 to Alert Level 1. As of the 24th of June, PHIVOLCS reported that seismic network recorded one (1) volcanic earthquake during the past 24 hours.  Field measurements conducted last 21 June 2011 at the western sector inside the Main Crater Lake showed that the water temperature increased from 32.9 ° C to 33.1°C, the water level increased from 0.33 meter to 0.60 meter and the water became more acidic (pH value from 2.88 to 2.62) as compared with the previous readings on 31 May 2011.  Minimal bubbling activity was observed at the middle portion of the Main Crater Lake.  Results of the ground deformation survey (precise leveling) conducted around the Volcano Island last 1 - 10 June 2011 showed that the volcano edifice is slightly inflated relative to the 26 April - 03 May 2011 survey. Measurement of carbon dioxide (CO2) gas emission rates last 03-04 May 2011 at Taal Main Crater Lake yielded a value of 2,057 tonnes per day (t/d) which is above the background level. As of the 17th of June, PHIVOLCS reported that Taal Volcano's seismic network recorded four (4) volcanic earthquakes during the past 24 hours.  Field measurements conducted last 14 June 2011 at the eastern sector inside the Main Crater Lake showed that the water temperature decreased to 32.9°C from 33.8 ° C, the water level increased to 0.59 meter from 0.31 meter and the pH value showed an insignificant change to 2.67 from 2.69 as compared with the previous readings on 7 June 2011.  Bubbling activity was observed at the middle portion of the Main Crater Lake. As of the 3rd of June, PHIVOLCS reported that seismic network recorded four (4) volcanic earthquakes during the past 24 hours.  Field measurements conducted last 31 May 2011 at the western sector inside the Main Crater Lake showed that the water temperature increased from 32.5 ° C to 32.9°C, and the pH value became more acidic decreasing from 2.72 to 2.60.  Bubbling activity was observed at the middle portion of the Main Crater Lake. As of the 2nd of June, PHIVOLCS reported that Taal Volcano's seismic network recorded thirteen (13) volcanic earthquakes during the past 24 hours. Two of these events were felt at   Intensity II by residents of Calauit located at the eastern sector of the volcano. The events were reportedly accompanied with rumbling sounds. As of the 1st of June, PHIVOLCS reported that Taal Volcano's seismic network recorded twenty two (22) volcanic earthquakes during the past 24 hours. Two of these events were felt at   Intensity II by residents of Calauit, Tuoran and Bignay located at the eastern sector of the volcano. The events were reportedly accompanied with rumbling sounds. Field measurements conducted on 31 May 2011 at the western sector inside the Main Crater Lake showed that the water temperature increased from 32.5 ° C to 32.9°C, and the pH value became more acidic decreasing from 2.72 to 2.60. Bubbling activity was observed at the middle portion of the Main Crater Lake. As of the 30th of May, PHIVOLCS reported that a remarkable increase in the seismic activity occured on Taal Volcano. For the past 24 hours, Taal‘s seismic network detected a total of one hundred fifteen (115) volcanic earthquakes during the past 24 hours. Twelve of these events were felt at Intensity I – IV by residents of Pira-piraso, Alas-as and Calauit located at northeast, southwest and southeast sectors of Volcano Island, respectively. One of these events (8:32 PM, 29 May) was felt at Intensity I, nine (9)  events (1:02:19 AM, 1:02:26 AM, 2:32 AM, 2:53 AM, 2:12 AM, 3:08:19 AM, 3:08:52 AM, 3:17 AM, 3:19 AM, 3:26 AM 30 May) were felt at Intensity II, one event (1:26 AM 30 May) was felt at Intensity III and another one (1:05 AM 30 May) was  felt at Intensity IV. All of these felt events were reportedly accompanied by rumbling sounds. As of the 26th of May, PHIVOLCS reported that seismic network recorded three (3) volcanic earthquakes during the past 24 hours. Field measurements conducted on 24 May 2011 at the eastern sector inside the Main Crater Lake showed that the water temperature slightly increased from 32.5 ° C to 32.8°C, the pH value became more slightly acidic decreasing from 2.83 to 2.67 and the water level increased from 0.21 meter to 0.25 meter. Results of the ground deformation survey (precise leveling) conducted around the Volcano Island last 26 April - 03 May 2011 showed that the volcano edifice inflated slightly relative to the 05-11 April 2011 survey. Measurement of carbon dioxide (CO2) gas emission rates last 03-04 May 2011 at Taal Main Crater yielded a lower value of 2,057 tonnes per day (t/d) compared with that measured last March 2011 which had a value of 4,750 t/d. However, the obtained value is still higher than the emission rates of 1,875 t/d measured last February 2011. Previously, as of the 18th of may, PHIVOLCS reported that Taal Volcano's seismic network recorded five (5) volcanic earthquakes during the past 24 hours.  As of the 13th of May, PHIVOLCS reported that seismic network recorded five (5) volcanic earthquakes during the past 24 hours. Field measurements conducted May 13, 2011 at the eastern sector inside the Main Crater Lake showed that the water temperature slightly increased from 32.0°C (May 5, 2011) to 32.5°C. The water is still acidic with the pH value remained at 2.94 and the water level slightly increased from 0.19 meter to 0.21 meter as compared with the reading on May 5, 2011. Results of the ground deformation measurement (precise leveling) conducted around the Volcano Island last 26 April -03 May 2011 showed that the volcano edifice is still inflated as compared with the 05-11 April 2011 survey. Results of gas measurements conducted between 03-04 May 2011 at Taal Main Crater yielded a carbon dioxide (CO2) emission rate of 2,057 tonnes per day (t/d). This emission value is down from 4,750 t/d last March 2011, but still higher than the emission rates of 1,875 t/d measured last February 2011. As of the 6th of May, PHIVOLCS reported that seismic network recorded six (6) volcanic earthquakes during the past 24 hours.  Field measurements conducted on 05 May 2011 at the eastern sector inside the Main Crater Lake showed that the water temperature increased from 31.5 ° C to 32.0 ° C, the water became more acidic with pH value decreasing from 3.09 to 2.94 and the water level further receded to 0.19 meters from the 0.23 meters as compared to the last reading on 19 April 2011. As of the 25th of April, PHIVOLCS reported that Taal Volcano's seismic network recorded fourteen (14 ) volcanic earthquakes during the past 24 hours.Field observation and measurements conducted at the eastern sector inside the Main Crater Lake showed that the water temperature increased from 30.5 ° C to 31.5 ° C. Result of the ground deformation survey (precise leveling) conducted around the Volcano Island last 05-11 April 2011 showed that volcano edifice is slightly inflated as compared with the 02-09 February 2011 survey. As of the 23rd of April, PHIVOLCS reported that seismic network recorded nineteen (19) volcanic earthquakes during the past 24 hours. One of these events, which occurred at 12:23 midnight, was felt at Intensity II at Brgy. Calauit on the southeastern part of the Volcano Island. Another event which occurred at 4:31 AM today was felt at Intensity III in Brgy. Pira-piraso at the northeastern part of Volcano Island accompanied by rumbling sounds.  Field observation and measurements conducted at the eastern sector inside the Main Crater Lake showed that the temperature at the Main Crater Lake increased from 30.5 ° C to 31.5 ° C. As of the 19th of April, PHIVOLCS reported that Taal Volcano's seismic network recorded six (6) volcanic earthquakes during the past 24 hours. Alert Level 2 is hoisted over Taal Volcano with the interpretation that magma has been intruding towards the surface, as manifested by CO 2 being released in the Main Crater Lake and increase in seismic activity.  Hence, PHIVOLCS advises the public that the Main Crater, Daang Kastila Trail and Mt. Tabaro (1965 -1977 Eruption Site) are strictly off-limits because sudden hazardous steam-driven explosions may occur and high concentrations of toxic gases may accumulate.  Breathing air with high concentration of gases can be lethal to human, animals and even cause damage to vegetation.  In addition, it is reminded that entire Volcano Island is a Permanent Danger Zone (PDZ), and permanent settlement in the island is strictly not recommended. Taal volcano is one of the most active volcanoes in the Philippines and has produced some of its most powerful historical eruptions. In contrast to Mayon volcano, Taal is not topographically prominent, but its prehistorical eruptions have greatly changed the topography of SW Luzon. The 15 x 20 km Talisay (Taal) caldera is largely filled by Lake Taal, whose 267 sq km surface lies only 3 m above sea level. The maximum depth of the lake is 160 m, and several eruptive centers lie submerged beneath the lake. The 5-km-wide Volcano Island in north-central Lake Taal is the location of all historical eruptions. The island is a complex volcano composed of coalescing small stratovolcanoes, tuff rings, and scoria cones that has grown about 25% in area during historical time. Powerful pyroclastic flows and surges from historical eruptions of Taal have caused many fatalities (gvn).

PHILIPPINES - Bulusan volcano

September 13th, 2011

As of the 13th of September, PHIVOLCS reported that Bulusan Volcano's seismic network detected one (1) volcanic earthquake during the past 24 hours. Steaming activity could not be observed due to thick clouds covering the summit. Ground deformation survey (precise leveling) conducted last 16 - 20 August 2011 yielded no significant change at Inlagadian leveling line on the NNE flank but yielded slight inflation at Mapaso leveling line on the SSE flank, relative to the previous survey last 07-09 June 2011. As of the 2nd of September, PHIVOLCS reported that Bulusan seismic network detected one (1) volcanic earthquake during the past 24 hours. Steaming activity could not be observed due to thick clouds that covered the summit crater and known thermal vents. As of the 6th of July, PHIVOLCS reported that Bulusan Volcano's seismic network did not record any volcanic earthquake during the past 24 hours.  Steaming activity at all known thermal vents was not observed due to cloudy weather.  Results of the ground deformation survey (precise leveling) conducted last 07-09 June 2011 showed no significant change relative to the 07-11 May 2011 survey. Bulusan Volcano's seismic network recorded thirty one (31) volcanic earthquakes during the past 24 hours. Steaming activity was not observed due to thick clouds covering the summit. Measurement of sulphur dioxide (SO2) flux conducted last 24 May 2011 yielded a value of 17 tonnes per day. Results of ground deformation survey (precise leveling) conducted last 07-11 May 2011 showed no significant change as compared with 01-05 March 2011 survey. Bulusan Volcano's seismic network recorded four (4) volcanic earthquakes during the past 24 hours.  Steaming activity at the active vents varied from wispy to moderate throughout the observation period. Measurement of Sulfur Dioxide flux last May 19, 2011 yielded a value of 18 tonnes/day. The seismic network at Bulusan Volcano detected a total of one hundred forty four (144) volcanic earthquakes for the past 24 hours. Steaming activity at the active vents was weak to moderate throughout the observation period. Results of ground deformation survey (precise leveling) conducted last 07-11 May 2011 showed no significant change as compared with 01-05 March 2011 survey.   At 12:25 AM today 13th of May, an explosion occurred at the summit crater of Bulusan Volcano but the event was not observed due to cloud cover. The explosion was accompanied by a rumbling sound heard up to five (5) kilometres away from the volcano. This event was recorded as an explosion type earthquake lasting for about ten (10) minutes. The seismic network detected a total of ten (10) volcanic earthquakes for the past 24 hours. Field investigation conducted immediately after the explosion confirmed the presence of thin (0.5- 2.5mm) ash deposits in the northwest and southwest sectors reaching approximately 9 kilometers away from the crater. Affected by light ashfalls were barangays of Caladgaw, Rangas, Puting- Sapa, Sangkayon, Bacolod, Buraburan, Gurayan, and Aniog in the municipality of Juban and barangays Cogon, Bolos, Umagom, and Gulang-gulang in the municipality of Irosin. The seismic network around Bulusan Volcano recorded seven (7) volcanic earthquakes during the past 24 hours. Steaming activity was not observed due to thick clouds covering the upper slope of the volcano. Results of ground deformation survey (precise leveling) conducted last 01-05 March 2011 showed no significant change as compared with 25-29 January 2011 survey.  No other significant volcanic activity was observed since the 21 February 2011 ash explosion.  No lahar event was reported or observed. During 12-19 April, PHIVOLCS reported that up to six daily volcanic earthquakes at Bulusan were detected by the seismic network. Although cloud cover mostly prevented observations of the summit area, steam was observed rising from NW and SE thermal vents during 15 and 17-18 April. Based on notices from the Manila airport (RPLL) and reports from PHIVOLCS, the Tokyo VAAC reported that ash was observed on 13 and 15 April. The seismic network around Bulusan Volcano did not record any volcanic earthquake during the past 24 hours.  Steaming activity was observed to be wispy to weak at the southeast vents while the northwest and active crater vents were cloud-covered.   No other significant volcanic activity was observed since the 21 February 2011 ash explosion.  No lahar event was reported or observed. Bulusan Volcano's seismic network recorded two (2) volcanic earthquakes during the past 24 hours.  Steaming activity was not observed due to clouds covering the summit the whole day yesterday.  Results of ground deformation survey (precise leveling) conducted last 01-05 March 2011 showed no significant change as compared with 25-29 January 2011 survey.  No other significant volcanic activity was observed since the 21 February 2011 ash explosion.  No lahar event was reported or observed. Bulusan Volcano's status remains at Alert Level 1. Based on notices from the Manila airport (RPLL), the Tokyo VAAC reported that during 25-26 March ash from Bulusan was observed. PHIVOLCS reported that cloud cover prevented ground-based observations. The seismic network around Bulusan Volcano detected one (1) volcanic earthquake during the past 24 hours. Steaming activity was not observed due to thick clouds covering the active vents and summit crater. Result of ground deformation survey (precise leveling) conducted last 01- 05 March 2011 showed no significant change as compared with 25-29 January 2011 survey. No other significant volcanic activity was observed since the 21 February 2011 ash explosion.  No lahar event was reported or observed. As of the 1st of March, PHIVOLCS reported that seismic network recorded three (3) volcanic earthquakes and nine (9) rockfall events during the past 24 hours. Steaming activity was not observed due to thick clouds covering the active vents and summit crater.  Confined muddy stream flow occurred at about 5:45 A. M. today at the Monbon Creek in San Benon. No other significant volcanic activity was observed since the 21 February. As of the 21st of february, PHIVOLCS reported that at 0912H today an explosion occurred at Bulusan Volcano. This event was recorded as explosion type earthquake lasting for about nineteen (19) minutes and was accompanied by a rumbling sound which was heard up to ten (10) kilometers away in the town of Juban , Sorsogon. The explosion produced a greyish ash column that rose to a height of about three (3) kilometres above the summit before drifting to the southwest. Preliminary field investigation confirmed the presence of ash deposits in Barangay Monbon and Irosin proper in Irosin Sorsogon. During 21-22 February 16 volcanic earthquakes were detected by the seismic network. The Alert Level remained at 1 (on a scale of 0-5). As of the 12th of February, PHIVOLCS reported that no volcanic earthquake was detected by Bulusan Volcano's seismic network during the past 24 hours. Steaming activity from the known thermal vents and crater was weak to no steaming.  No sulfur dioxide (SO 2 ) flux was detected during measurements conducted yesterday. Results of ground deformation surveys conducted last January 25 - 29, 2011 showed that the volcanic edifice was slightly deflated relative to December 2010 survey. As of the 5th of February, PHIVOLCS reported that the seismic network recorded one (1) volcanic earthquake during the past 24 hours. No steaming activity was observed from the crater and known thermal vents.  Results of ground deformation surveys conducted last January 25 - 29, 2011 showed that the volcanic edifice was slightly deflated relative to December 2010 survey. As of the 27th of January, PHIVOLCS reported that no volcanic earthquake was recorded by the seismic network during the past 24 hours.  Steaming activity from known thermal vents was not observed due to thick clouds covering the summit.  As of the 24th of January, PHIVOLCS reported that no volcanic earthquake was recorded by the seismic network during the past 24 hours. Steaming activity from known thermal vents was not observed due to thick clouds covering the summit. Results of ground deformation surveys conducted last November and December 2010 showed that the volcanic edifice was slightly deflated relative to August 2010 survey. As of the 21st of January, PHIVOLCS reported that the seismic network recorded three (3) volcanic earthquakes during the past 24 hours.  Wispy to weak steam emission was observed at the SE thermal vent.  The crater and other known thermal vents were covered by thick clouds. No lahar event was reported or observed.  Results of ground deformation surveys conducted last November and December 2010 showed that the volcanic edifice was slightly deflated relative to August 2010 survey. As of the 18th of January, PHIVOLCS reported that at around 2:58 A.M, today, an explosion occurred at the summit crater of Bulusan Volcano. This was accompanied by a rumbling sound audible at Monbon, Irosin.  The explosion was not observed because the volcano summit was covered by thick clouds.  Field investigation conducted this morning confirmed the presence of traces of ash deposits in Monbon, Irosin. As of the 14th of January, PHIVOLCS reported that the seismic network at Bulusan Volcano recorded one (1) volcanic earthquake during the past 24 hours. Visual observation of the crater and known thermal vents were not possible due to thick clouds that covered the entire summit area. No measurement of sulphur dioxide (SO 2 ) emission rate was conducted yesterday due to rainy weather. Likewise, no lahar event was observed. Results of ground deformation surveys conducted last November and December 2010 showed that the volcanic edifice was slightly deflated relative to August 2010 survey. At 9:16 A.M. 0n 23rd of December,, an ash explosion occurred at the summit crater of Bulusan Volcano.  A grayish steam and ash column rose to about 500 meters above the crater rim and drifted south-southwest.  The event was recorded as an explosion type volcanic earthquake preceded by a tremor type volcanic earthquake that lasted for thirty minutes and fifty seconds.  Field investigation carried out immediately after the explosion showed that no ashfall was observed beyond the 4-km Permanent Danger Zone (PDZ). As of the 17th of december PHIVOLCS reported that at 2:17 P.M. yesterday, an explosion occurred at the summit crater. The explosion produced a grayish steam and ash column that rose to about 500 meters above the crater rim and drifted to the southwest. The event was recorded as an explosion-type earthquake lasting for three minutes. Field investigation carried out immediately after the explosion showed that no ashfall was observed beyond the 4-km Permanent Danger Zone (PDZ). During the past 24 hours, four (4) volcanic earthquakes were detected by the Bulusan seismic network. No steaming was observed at the northwest and southeast vents while weak to very weak steam emission were seen rising from the summit crater. No sulfur dioxide (SO 2 ) flux was detected during the measurements conducted yesterday. As of the 14th of December, PHIVOLCS reported that during 8-12 December 1-2 volcanic earthquakes from Bulusan were detected by the seismic network. Cloud cover prevented visual observations. On 13 December, 7 volcanic earthquakes were detected. Steam rose from the crater and known thermal vents. The Alert Level remained at 1 (on a scale of 0-5). As of the 7th of december, PHIVOLCS reported that volcanic earthquakes from Bulusan were detected during 1-6 December; no earthquakes were recorded on 7 December. Steam from known thermal vents rose 100 m and drifted SW on 1 December. Cloud cover prevented visual observations during 2-4 and 6-7 December. Diffuse steam rose from the crater and from known vents on 5 December. The Alert Level remained at 1 (on a scale of 0-5). As of the 25th of November, PHIVOLCS reported that at 1:22PM yesterday, an explosion occurred in Bulusan Volcano. This was recorded in the seismographs as an explosion-type earthquake lasting five (5) minutes and fifty (50) seconds. The event produced a cloud of ash and steam, 1-kilometer high above the crater rim and slowly drifting and dissipating to the southwest. However, no deposits of ash were observed outside the 4-kilometer PDZ, suggesting that the ash were confined to the upper slopes of the volcano. The average sulphur dioxide (SO2) flux emitted by the volcano today is at twenty-two (22) tonnes per day. After ash explosion seismic network recorded a total of eleven (11) volcanic earthquakes. Steaming activity varied from wispy to voluminous with white steam columns reaching a maximum height of 300-500 meters above the crater rim before drifting south-southwest to south. Yesterday's measurement of sulfur dioxide (SO2) emission rate produced an average value of twenty two (22) tonnes per day. As of the 22nd of November, PHIVOLCS reported thatTwenty-eight (28) volcanic earthquakes were recorded by Bulusan Volcano's seismic network since 6AM today. One of which was an explosion type earthquake that ejected a grayish volcanic ash, 2km high and drifted to southwest direction. Ash affected areas are municipalities of Irosin (Cogon, Sangkayon, Monbon, Irosin proper, Onagon, Bolos and Gulanggulang with dusting to 3mm thick ash), Bulan (Aquino, Sumagunsong, Bulan proper, San Francisco, Quirino, Palale and Cadananan with traces of ash up to 2mm thick) and Magallanes (Tulatula, Busay and Siuton with traces of ash). As of the 20th of November, PHIVOLCS reported that the seismic network around Bulusan Volcano detected a total of fifteen (15) volcanic earthquakes during the past 24 hours.  Thick clouds covering the summit of the volcano hampered visual observation. As of the 16th of November, PHIVOLCS reported that another ash explosion accompanied by rumbling sounds occurred at 11:47 last night from the summit crater of Bulusan Volcano. The event was reflected by the seismograph as an explosion-type quake lasting for four (4) minutes and 30 seconds. The height of the ash column was not observed due to darkness.  Ashfalls were experienced at barangays Bolos, Gulang-gulang, Tinampo and Monbon, Municipality of Irosin.  The seismic network detected fifty (50) volcanic earthquakes during the past 24 hours. Prior to the activity, weak emission of white steam clouds was observed from the crater and the NW vents. Yesterday's sulfur dioxide measurement yielded an average value of 38 tonnes per day. As of the 13th of November, PHIVOLCS reported that during the past 24-hours, steaming activity at the summit of Bulusan Volcano varied from wispy to moderate, reaching up to maximum height of 100 meters before drifting to SW direction. The seismic network detected no volcanic earthquake during the same observation period. Yesterday's measurement of sulfur dioxide emission rate yielded an average value of 125 tonnes per day. As of the 12th of November, PHIVOLCS reported that a new ash explosion occurred at 6:59 A.M. from the summit crater of Bulusan Volcano. The explosion produced an ash and steam cloud which rose to about 700 meters above the volcano's summit and drifted southwest. PHIVOLCS volcanologists at the site are conducting field investigation on the areas affected by ashfalls. The seismic network detected a total of four (4) volcanic earthquakes during the past 24 hours. Prior to the ash explosion, weak steaming was observed from the crater during times of good visibility. As of the 10th of November, the Philippine Institute of Volcanology and Seismology (PHIVOLCS) reported thatTwo (2) episodes of ash explosions occurred at 3:30 PM and 3:43 PM yesterday from the crater of Bulusan Volcano. The steam driven explosions produced grayish ash columns that reached heights of approximately 1000m and 800m, respectively, above the crater and drifted to the southwest.  Both explosions were accompanied by rumbling sounds heard at Barangay Monbon in Irosin. Field investigation conducted by PHIVOLCS volcanologists yesterday confirmed that ashfall affected the following areas: Barangays Cogon (2.0mm), Tinampo (1.0mm), Monbon (1.0mm), town proper and Bolos (traces) in Irosin and Barangay Sangkayon (traces) in Juban, all located in the SW and WNW sectors of the volcano.  Sulfur Dioxide (SO2) emission rate measured yesterday yielded a value of 168 tonnes per day.  Prior to the explosions, the seismic network detected two (2) volcanic earthquakes.  For the past 24 hour observation period, steaming activity varied from very weak to moderate.Dozens of people fled their homes Wednesday, while authorities advised pilots to avoid flying near clouds of fine ash shooting out from its crater. As the 9th of November, PHIVOLCS reported that seismic network detected a total of eight (8) volcanic earthquakes during the past 24 hours. The summit of the volcano was most of the time obscured by thick clouds. However, during times of good visibility weak to moderate emission of white steam was observed. The November 6 and 8, 2010 ash explosions are typical of Bulusan Volcano's activity during its restive period. PHIVOLCS expects more explosions to occur in view of the volcano's recent reactivation. Hence, Alert Level 1 is reiterated to reflect the present activity at Bulusan. Areas within 4 kilometers of the summit has been designated a Permanent Danger Zone (PDZ) which means that the public is strongly advised not to venture inside this area because it may be affected by sudden steam explosions. Meanwhile, the people residing near valleys and streams are also advised to be vigilant against sediment-laden stream flows in the event of heavy and continuous rainfall. Due to the prevailing wind residents located in the northwest and southwest sectors of the volcano are advised to take precautions against ashfalls. Civil aviation authorities must advise pilots to avoid flying close to the volcano's summit as ejected ash and volcanic fragments from sudden explosions may pose hazards to aircrafts. Bulusan, 250 kilometres (160 miles) southeast of the capital Manila on the main island of Luzon, is one of the country's 23 active volcanoes. Luzon's southernmost volcano, Bulusan, was constructed along the rim of the 11-km-diameter dacitic-to-rhyolitic Irosin caldera, which was formed about 36,000 years ago. Bulusan lies at the SE end of the Bicol volcanic arc occupying the peninsula of the same name that forms the elongated SE tip of Luzon. A broad, flat moat is located below the topographically prominent SW rim of Irosin caldera; the NE rim is buried by the andesitic Bulusan complex. Bulusan is flanked by several other large intracaldera lava domes and cones, including the prominent Mount Jormajan lava dome on the SW flank and Sharp Peak to the NE. The summit of 1565-m-high Bulusan volcano is unvegetated and contains a 300-m-wide, 50-m-deep crater. Three small craters are located on the SE flank. Many moderate explosive eruptions have been recorded at Bulusan since the mid-19th century.

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INDONESIA Volcanoes activity VSI - CVGHM reports : Recent events in 2011 - 2012

Gamalama volcano ( Ternate) -CVGHM lowered the Alert Level for Gamalama from 3 to 2 (on a scale of 1-4)
on 24 January based on visual observations of white plumes rising as high as 100 m above the crater and a decrease in seismicity since the last eruption on 23 December 2011. According to news articles, at least three people were killed and 1,000-2,600 more from several villages were displaced by lahars from Gamalama during on 27-28 December. The lahars destroyed many homes in the Tubo and Tofure villages and along the Togorara and Marikurubu rivers. The Alert Level remains at 3 (on a scale from 1-4). Based on a SIGMET and information from the Ujung Pandang City MWO, the Darwin VAAC reported that on 14 December an ash plume from Gamalama rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted 140 km S. Based on information from CVGHM, the Darwin VAAC reported that during 7-10 December ash plumes from Gamalama rose to altitudes of 2.1-6.1 km (7,000-20,000 ft) a.s.l. and drifted E and SE. The Alert Level for Gamalama remains at 3 (on a scale from 1-4). Based on information from CVGHM, the Darwin VAAC reported that during 5-6 December ash plumes from Gamalama rose to altitudes of 2.4-3.0 km (8,000-10,000 ft) a.s.l. and drifted SE. As of the 5th of December 2011, VSI reported that Mount Gamalama erupted late Sunday and ejected hot ash to about 2000 high prompting thousands of residents to flee the volcano. VSI reported no information about possible casualties after the volcano first erupted late on Sunday. The island airport was closed on Monday and until everything will be normalized. Following this increasing activity residents were returning to their homes, although authorities were keeping the volcano at the second highest level of alert. Gamalama (Peak of Ternate) is a near-conical stratovolcano that comprises the entire island of Ternate off the western coast of Halmahera and is one of Indonesia's most active volcanoes. The island of Ternate was a major regional center in the Portuguese and Dutch spice trade for several centuries, which contributed to the thorough documentation of Gamalama's historical activity. Three cones, progressively younger to the north, form the summit of Gamalama, which reaches 1715 m. Several maars and vents define a rift zone, parallel to the Halmahera island arc, that cuts the volcano. Eruptions, recorded frequently since the 16th century, typically originated from the summit craters, although flank eruptions have occurred in 1763, 1770, 1775, and 1962-63. GVN/GVP

Marapi volcano (Sumatra) - Based on information from CVGHM, the Darwin VAAC reported that on 12 October 2011 an eruption from Marapi produced an ash plume that rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted E. Based on a pilot report, the Darwin VAAC reported that on 11 October an ash plume from Marapi rose to an altitude of 3.7 km (12,000 ft) a.s.l. Ash was not identified in satellite imagery. According to a news article, two eruptions from Marapi occurred on 9 August. The article also noted that the Alert Level remained at 2 (on a scale of 1-4). As of the 4th of August 2011 PVMBG reported that following increasing tremor signal yesterday an explosive activity started from the summit zone of the volcano. According to a preliminary report eight explosions occured generating a grey volcanic plume to about 1000 m high. This explosive activity was visible on Modis image taken at 03h.20 TU yesterday. Ashfall occured on several villages around like comme Padang Pajang (11 km au south-east). That same day CVGHM raised the Alert Level to 2 (on a scale of 1-4). The recommended security zone is set at a three-kilometre radius around the volcano. Gunung Marapi, not to be confused with the better-known Merapi volcano on Java, is Sumatra's most active volcano. Marapi is a massive complex stratovolcano that rises 2000 m above the Bukittinggi plain in Sumatra's Padang Highlands. A broad summit contains multiple partially overlapping summit craters constructed within the small 1.4-km-wide Bancah caldera. The summit craters are located along an ENE-WSW line, with volcanism migrating to the west. More than 50 eruptions, typically consisting of small-to-moderate explosive activity, have been recorded since the end of the 18th century; no lava flows outside the summit craters have been reported in historical time. Last known activity reported occured in 2004.

Kawah Ijen volcano (Java) - 2011 news - CVGHM reported that during 1 October-30 November white plumes from Ijen rose 50-150 m above the crater and lake water temperatures ranged from 26 to 31.6 degrees Celsius. During 1-14 December brownish-white plumes rose 50-200 m above the crater. The lake water temperature was 26.8 and 34.2 degrees Celsius on 8 and 14 December, respectively. Based on increased seismicity, visual observations, and lake water temperature increases, CVGHM raised the Alert Level from 1 to 2 (on a scale of 1-4). During 15-17 December seismicity significantly increased and sulfur dioxide gas emissions around the lake also increased. On 17 December the color of the lake water changed from light green to white. The Alert Level was raised to 3 the next day. The Ijen volcano complex consists of a group of small stratovolcanoes constructed within the large 20-km-wide Ijen (Kendeng) caldera. The N caldera wall forms a prominent arcuate ridge, but elsewhere the caldera rim is buried by post-caldera volcanoes, including Gunung Merapi stratovolcano, which forms the 2,799 m high point of the Ijen complex. Immediately W of Gunung Merapi is the renowned historically active Kawah Ijen volcano, which contains a nearly 1-km-wide, turquoise-colored, acid crater lake. The picturesque lake is the site of a labor-intensive sulfur mining operation, in which sulfur-laden baskets are hand-carried from the crater floor. A half dozen small-to-moderate phreatic eruptions have taken place from Kawah Ijen during the 20th century.

Papandayan volcano (Java) - 2011 news - On 26 August CVGHM reported that Papandayan showed minor to no changes in recent seismicity, deformation, geochemistry, and visual observations; therefore the Alert Level remained at 3 (on a scale of 1-4). Seismicity remained high, but stable, and was dominated by shallow volcanic earthquakes. Deformation measurements showed no change, and water temperatures in multiple fumarolic areas and lakes remained relatively unchanged. Sulfur dioxide gas emissions decreased from 8 tons per day on 12 August to 6 tons per day on 23 August. Carbon dioxide in the soil at a 1 m depth in multiple areas did not increase. Visitors and residents were advised not to venture within 2 km of the active crater.
On 13 August 2011, CVGHM reported that, based on seismicity, deformation, geochemistry, and visual observations, the Alert Level for Papandayan was raised to 3 (on a scale of 1-4). During 1 June-12 August sulfur plumes rose 20-75 m above the vents. During the same period, seismicity increased with several hundreds of earthquakes detected per month. Temperature measurements in the Manuk thermal area indicated a relative increase from 29 June to 12 August and deformation measurements indicated inflation from 4 July to 10 August. Visitors and residents were not to venture within 2 km of the active crater. Papandayan is a complex stratovolcano with four large summit craters, the youngest of which was breached to the NE by collapse during a brief eruption in 1772 and contains active fumarole fields. The broad 1.1-km-wide, flat-floored Alun-Alun crater truncates the summit of Papandayan, and Gunung Puntang to the N gives the volcano a twin-peaked appearance. Several episodes of collapse have given the volcano an irregular profile and produced debris avalanches that have impacted lowland areas beyond the volcano. Since its first historical eruption in 1772, in which a catastrophic debris avalanche destroyed 40 villages, only two small phreatic eruptions have occurred from vents in the NE-flank fumarole field, Kawah Mas. (GVN/GVP)

Mount Semeru ( Java) - 2010 - news - As of the 4th of November 2010, CVGHM reported that from August to October seismic activity at Semeru had increased, and "smoke" and occasional gas plumes rose 400-500 m above the crater. During September incandescent avalanches traveled 400 m SE into the Besuk Kembar drainage on three occasions. Incandescence from the crater was observed in October. Incandescent avalanches traveled 600 m E into Besuk Kembar on 2 November and 4 km into the Besuk Kembar and Besuk Bang (SSE) drainages on 4 November. CVGHM noted that the lava dome in the Jonggring Saloko crater was growing. The Alert Level remained at 2 (on a scale of 1-4). Semeru, the highest volcano on Java, and one of its most active, lies at the southern end of a volcanic massif extending north to the Tengger caldera. The volcano, rises abruptly to 3676 m above coastal plains to the south. Gunung Semeru was constructed south of the overlapping Ajek-ajek and Jambangan calderas. A line of lake-filled maars was constructed along a N-S trend cutting through the summit, and cinder cones and lava domes occupy the eastern and NE flanks. Summit topography is complicated by the shifting of craters from NW to SE. Frequent 19th and 20th century eruptions were dominated by small-to-moderate explosions from the summit crater, with occasional lava flows and larger explosive eruptions accompanied by pyroclastic flows that have reached the lower flanks of the volcano. Semeru has been in almost continuous eruption since 1967

Mount Bromo (Java) - 2011 News - CVGHM reported that during 1-10 May white-to-gray ash plumes from Tengger Caldera's Bromo cone rose 400-600 m above the crater and drifted ENE, and incandescence emanated from the crater. During 11-20 May white-to-gray ash plumes rose 200-400 m above the crater and drifted E. Ash plumes continued to rise from the crater during 1-13 June to heights of 100-200 m above the crater and drifted E. Ash continued to fall in areas within 2 km E and NE during May and June. On 13 June the Alert Level was lowered to 2 (on a scale of 1-4). Based on analyses of satellite imagery, the Darwin VAAC reported that during 9-10 May ash plumes from Tengger Caldera's Bromo cone rose to an altitude of 2.7 km (9,000 ft) a.s.l. and drifted 45-75 km NE and E. Based on analyses of satellite imagery, the Darwin VAAC reported that on 27 April 2011 an ash plume from Tengger Caldera's Bromo cone rose to an altitude of 4.3 km (14,000 ft) a.s.l. and drifted about 75 km WSW. On 2 May an ash plume rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted about 75 km N. As of the 4th of April, at 00:00 to 6:00 pm, the eruption is still continuous, thick gray smoke white crater, medium-strong pressure, high smoke ± 400-800 m. inclined to the East - Northeast carry volcanic ash material. Observed fire rays from the crater lip. still sounded weak roar. It was raining ash in the G. Observation Post Bromo. CVGHM reported that during 29 March - 4 April 2011 brownish-gray ash plumes from Tengger Caldera's Bromo cone rose 400-800 m above the crater and drifted N, E, and NE. Ash fell at the Bromo observation post. Incandescence emanated from the crater and incandescent material was periodically ejected above the crater. Roaring of varying intensity was heard. The Alert Level remained at 3 (on a scale of 1-4). Residents and tourists were not permitted within a 2-km radius of the active crater. Based on analyses of satellite imagery, the Darwin VAAC reported that during 27-28 March ash plumes rose to an altitude of 4.3 km (14,000 ft) a.s.l. and drifted 55 km NE. As of the 25th of march, DVGHM reported that at 00:00 to 6:00 pm, the eruption was over, the smoke thick brownish-gray crater, medium-strong pressure, high smoke ± 400-800 m leaning Northeast - East by bringing the material of volcanic ash. Observed burst of incandescent material with a height of ± 300 m from the lip of the crater and ejected as far as ± 250 m.still audible sound was the roar and boom. It was raining ash in the G. Observation Post Bromo. Based on analyses of satellite imagery and information from CVGHM, the Darwin VAAC reported that during 18-20 March ash plumes rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted 27-150 km NW, SW, and S. CVGHM reported that during 17-18 February brownish gray ash plumes from Tengger Caldera's Bromo cone rose 400-800 m above the crater and drifted ENE. Incandescent material was ejected 300 m above the crater and landed as far as 500 m away, and roaring and booming was heard. The Alert Level remained at 3 (on a scale of 1-4). Residents and tourists were not permitted within a 2-km-radius of the active crater. CVGHM reported that during 8-9 February 2011 gray-to-brown ash plumes from Tengger Caldera's Bromo cone rose 400-800 m above the crater and drifted E. Incandescent material was ejected 300 m above the crater and landed as far as 500 m away, and roaring and booming was heard. Ash fell at the Bromo observation post on 8 February. The Alert Level remained at 3 (on a scale of 1-4). Residents and tourists were not permitted within a 2-km-radius of the active crater. Based on a pilot observation, the Darwin VAAC reported that on 9 February an eruption produced a plume that rose to an altitude of 7 km (23,000 ft) a.s.l. and drifted W. On 11 February satellite imagery showed an ash plume drifting 37 km SE at an altitude of 3 km (10,000 ft) a.s.l. Ash plumes on 12 February rose to altitudes of 3-7.9 km (10,000-26,000 ft) a.s.l. and drifted 37-167 km NW and SE. CVGHM reported that on 5 February 2011 volcanic bombs ejected from Tengger Caldera's Bromo cone were found 1.2-1.4 km from the crater rim. During 5-8 February gray-to-brown ash plumes rose 400-800 m above the crater and drifted ENE. Incandescent material was ejected 200-300 m above the crater and landed as far as 500 m away. Recent Bromo photos . Ash fell at the Bromo observation post, and in nearby villages including Ngadirejo (10 km WNW), Sukapura (14 km NE), and Sumber (18 km E). High-amplitude seismicity and volcanic tremor were detected. Deformation measurements had remained stable since 31 December 2010. The Alert Level remained at 3 (on a scale of 1-4). Residents and tourists were not permitted within a 2-km-radius of the active crater. As of the 4th of February, the eruptive activity was still continuing. Eruptive plume rose to about 400-800 m high and and glowing ejecta rose to 200 m above the crater rim. According to news articles, ash plumes from Tengger Caldera's Bromo cone caused flights between Perth and Bali to be disrupted during 27-28 January 2011. Based on analysis of satellite imagery, the Darwin VAAC reported that on 28 January an ash plume rose to an altitude of 5.5 km (18,000 ft) a.s.l. and drifted 370 km E and SE. On 29 January an ash plume rose to an altitude of 3.7 km (12,000 ft) a.s.l. and drifted 93 km E. The ash cloud from the previous day was again detected and slowly drifted N. The 16-km-wide Tengger caldera is located at the northern end of a volcanic massif extending from Semeru volcano. The massive Tengger volcanic complex dates back to about 820,000 years ago and consists of five overlapping stratovolcanoes, each truncated by a caldera. Lava domes, pyroclastic cones, and a maar occupy the flanks of the massif. The Ngadisari caldera at the NE end of the complex formed about 150,000 years ago and is now drained through the Sapikerep valley. The most recent of the Tengger calderas is the 9 x 10 km wide Sandsea caldera at the SW end of the complex, which formed incrementally during the late Pleistocene and early Holocene. An overlapping cluster of post-caldera cones was constructed on the floor of the Sandsea caldera within the past several thousand years. The youngest of these is Bromo, one of Java's most active and most frequently visited volcanoes.(gvn/gvp)

Lokon-Empung volcano (Sulawesi) ) - CVGHM reported that on 27 December seismic activity at Lokon-Empung suggested that an eruption had occurred, but fog prevented visual observations of the crater area. CVGHM noted on 28 December that the Alert Level remained at 3 (on a scale of 1-4), and reminded residents and tourists to not approach within a 2.5 km radius of the crater. Based on information from CVGHM, the Darwin VAAC reported that on 29 December an ash plume rose to an altitude of 3.7 km (12,000 ft) a.s.l According to a news article, three explosions from the Tompaluan crater, in the saddle between the Lokon-Empung peaks were recorded by the CVGHM on 27 December. CVGHM recorded 23 deep volcanic tremors and 40 shallow volcanic tremors. Residents and tourists were not permitted within a 2.5 km radius of the crater. Based on visual and seismic observations during 27-28 December, the Alert Level remained at 3 (on a scale of 1-4). The Darwin VAAC reported a low-level eruption on 27 December based on media reports. According to a news article, a gray plume rose 1.2 km above Tompaluan crater, in the saddle between the Lokon-Empung peaks, and drifted SW on 26 October, followed by an explosion that sent incandescent material as far as 800 m away from Tompaluan crater. A second eruption produced a plume that rose 500 m above the crater. CVGHM reported that on 10 October white and gray plumes rose 100-300 m above Tompaluan crater, in the saddle between the Lokon-Empung peaks. Based on information from CVGHM, the Darwin VAAC reported that on 11 October an ash plume rose to an altitude of 2.1 km (7,000 ft) a.s.l. The Alert Level remained at 3 (on a scale of 1-4). The twin volcanoes Lokon and Empung, rising about 800 m above the plain of Tondano, are among the most active volcanoes of Sulawesi. Lokon, the higher of the two peaks (whose summits are only 2.2 km apart) has a flat, craterless top. The morphologically younger Empung volcano has a 400-m-wide, 150-m-deep crater that erupted last in the 18th century, but all subsequent eruptions have originated from Tompaluan, a 150 x 250 m wide double crater situated in the saddle between the two peaks. Historical eruptions have primarily produced small-to-moderate ash plumes that have occasionally damaged croplands and houses, but lava-dome growth and pyroclastic flows have also occurred.

Ibu volcano (Halmahera) - CVGHM reported mostly clear conditions at Ibu during January-8 September 2011 and that white-to-gray plumes were observed rising 200-400 m above the craters. On 20 August observers from the nearby villages of Goin and Duono noted multiple eruptions from the S, E, and N craters. Eruption "smoke" rose 50-250 m above the craters and an avalanche traveled 300 m. Seismicity indicating avalanches occurred on average 45 times per day during January-8 September. Other types of seismic signals fluctuated during the time period but stabilized or decreased towards September. Based on visual observations and seismicity, CVGHM lowered the Alert Level to 2 (on a scale of 1-4) on 8 September. The truncated summit of Gunung Ibu stratovolcano along the NW coast of Halmahera Island has large nested summit craters. The inner crater, 1 km wide and 400 m deep, contained several small crater lakes through much of historical time. The outer crater, 1.2 km wide, is breached on the north side, creating a steep-walled valley. A large parasitic cone is located ENE of the summit. A smaller one to the WSW has fed a lava flow down the western flank. A group of maars is located below the northern and western flanks of the volcano. Only a few eruptions have been recorded from Ibu in historical time, the first a small explosive eruption from the summit crater in 1911. An eruption producing a lava dome that eventually covered much of the floor of the inner summit crater began in December 1998. (GVN/GVP)

Gamkonora ( Halmahera) - As of the 5th of May 2011, CVGHM reported that during January-April diffuse white plumes from Gamkonora rose 25-100 m above the crater rim. Seismicity increased during 29 April-3 May. On 1 May, white plumes rose 150 m above the crater rim. The next day, white plumes rose 300 m above the crater rim and incandescence from the crater was observed. Residents near the volcano's base noted a sulfur smell. The Alert level was raised to 2 (on a scale of 1-4). The shifting of eruption centers on Gamkonora, at 1635 m the highest peak of Halmahera, has produced an elongated series of summit craters along a N-S trending rift. Youthful-looking lava flows originate near the cones of Gunung Alon and Popolojo, south of Gamkonora. Since its first recorded eruption in the 16th century, Gamkonora has typically produced small-to-moderate explosive eruptions. Its largest historical eruption, in 1673, was accompanied by tsunamis that inundated villages.

G. Merapi (Java) - 2011 News - CVGHM reported that during 29 August-4 September 2011 white solfatara plumes rose at most 350 m above Merapi and drifted W. On 4 September small avalanches traveled 700 m SW. The Alert Level remained at 2 (on a scale of 1-4). Based on a pilot observation, the Darwin VAAC reported that on 8 September an ash plume rose to an altitude of 3.7 km (12,000 ft) a.s.l. and drifted almost 30 km N. Merapi, one of Indonesia's most active volcanoes, lies in one of the world's most densely populated areas and dominates the landscape immediately north of the major city of Yogyakarta. Merapi is the youngest and southernmost of a volcanic chain extending NNW to Ungaran volcano. Growth of Old Merapi volcano beginning during the Pleistocene ended with major edifice collapse perhaps about 2000 years ago, leaving a large arcuate scarp cutting the eroded older Batulawang volcano. Subsequently growth of the steep-sided Young Merapi edifice, its upper part unvegetated due to frequent eruptive activity, began SW of the earlier collapse scarp. Pyroclastic flows and lahars accompanying growth and collapse of the steep-sided active summit lava dome have devastated cultivated lands on the volcano's western-to-southern flanks and caused many fatalities during historical time. The volcano is the object of extensive monitoring efforts by the Merapi Volcano Observatory (GNV/GVP)

Dukono (Halmahera) - Based on analyses of satellite imagery, the Darwin VAAC reported that during 30-31 January ash plumes from Dukono rose to an altitude of 2.7 km (9,000 ft) a.s.l. and drifted 220 km SW.
Based on analyses of satellite imagery, the Darwin VAAC reported that during 13-15 December ash plumes from Dukono rose to an altitude of 2.1 km (7,000 ft) a.s.l and drifted 55-75 km SW. Based on analyses of satellite imagery, the Darwin VAAC reported that on 13 December an ash plume from Dukono rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted 74 km SW. Based on analyses of satellite imagery, the Darwin VAAC reported that on 29 November ash plumes from Dukono rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted 65 km NW. Based on analyses of satellite imagery, the Darwin VAAC reported that during 27 October-1 November ash plumes from Dukono rose to altitudes of 2.1-2.7 km (7,000-9,000 ft) a.s.l. and drifted 35-110 km W, NW, and NE. Based on analyses of satellite imagery, the Darwin VAAC reported that on 22 October ash plumes from Dukono rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted 110-185 km W. Reports from this remote volcano in northernmost Halmahera are rare, but Dukono has been one of Indonesia's most active volcanoes. More-or-less continuous explosive eruptions, sometimes accompanied by lava flows, occurred from 1933 until at least the mid-1990s, when routine observations were curtailed .

G. Karangetang (Siau Island)- CVGHM reported that during July and August 2011 cloud cover often prevented observations of Karangetang, although white smoke was sometimes observed rising as high as 500 m above the crater. At night incandescence up to 10 m was often observed. On 8 July a phreatic eruption occurred from the N part of the Main Crater, ejecting material 150 m high. On 24 July and 1 August incandescent material traveled 1,500 m from the Main Crater. Sounds indicating an eruption were heard on 7 August, although fog prevented observations of the crater. Based on recent visual observations and increased seismicity, the Alert Level was raised to 3 (on a scale of 1-4) on 8 August. According to a news article, about 600 people living on the flanks evacuated. CVGHM reported that during 25 March-5 June 2011 seismic activity at Karangetang decreased along with the potential threat of avalanches and pyroclastic flows. During 1 May-5 June no pyroclastic flows were observed. Lava flowed 200 m down the flanks and produced incandescent material from the flow fronts that traveled an additional 1.5-1.8 km. Bluish-white emissions rose as high as 500 m from the main crater and incandescence from the crater was observed at night. Lava flow and avalanche activity decreased on 19 May. The Alert Level was lowered to 2 (on a scale of 1-4) on 6 June. As of the 25th of March 2011, DVGHM reported that at 00:00 to 06:00 pm, weather cloudy, calm wind, rain drizzle - is, volcanic fog - was evident. Thunder weak - often sounded a bit strong and accompanied by bursts of lava with a high 25 m. Observed-ray high-fire with 75-250 m. From leleran 600 m of lava at the point of common incandescent lava into Nanitu time as far as 500 m, occasionally from leleran 1500 m of lava at the point of glowing lava avalanche occurred to Kali Nanitu and Sense far as 50-200 m. Incandescent lava from the crater often happen to Kali Nanitu and Pangi as far as 500 - 1000 m. Based on observation and analysis of visual data, seismicity, and potential danger of eruption, then until March 25, 2011 at 12:00 pm, on the level of activity G. Karangetang assessed as to the status CAUTION (Level IV). Emergency Response Team continues to evaluate activities of G. Karangetang intensively and coordinate with local government. On 20 March lava flows traveled 1.8 km and avalanches from the lava flow fronts again went 500 m. Incandescent material rolled 1.5 km down the flanks and pyroclastic flows traveled 2.3 km from the crater. According to news articles, 600-1,200 people were evacuated from villages on the W flank. As of the 18th of March, the eruptive activity was continuing. During the night from 17th to 18th, a paroxysmal phase started when Mount Karangetang spewed hot clouds of ash and trapped up to 40 people between flows on its slopes on Friday. Pyroclastic flows went down into Sangi Nanitu and Pangi gullies. The government raised an alert for the peak to the highest level and evacuated villages. Lava streamed 1,500 meters down the volcano and hot plume rose to about 3,800 meters high. There were no reports of injuries, but several houses and a church were damaged. As of the 13th of March 2011, CVGHM reported that the volcano has erupted, on the 11th of March at 1:06 PM sending lava and an ash plume rose to an altitude of 2.4 km (8,000 ft). a.s.l. and drifted 55 km SW. According to news reports, lava flows at the summit were visible on 11 March. Blocks originating from the lava dome traveled as far as 2 km down the flanks. Hot gas clouds also descended the flanks. The VAAC also noted that on 13 March an ash plume rose to an altitude of 3.7 km (12,000 ft) a.s.l. and drifted 37 km. The 1784-m-high stratovolcano contains five summit craters along a N-S line. Karangetang is one of Indonesia's most active volcanoes, with more than 50 eruptions recorded since 1675 and many additional small eruptions that were not documented in the historical record (Catalog of Active Volcanoes of the World: Neumann van Padang, 1951). Twentieth-century eruptions have included frequent explosive activity sometimes accompanied by pyroclastic flows and lahars. Lava dome growth has occurred in the summit craters; collapse of lava flow fronts has also produced pyroclastic flows.

Anak Krakatau ( Sunda Strait) - CVGHM lowered the Alert Level for Anak Krakatau from 3 to 2 (on a scale of
1-4) on 26 January. No details or reasons for the change were given in the report. On 8 October, a news article stated that activity at Anak Krakatau was increasing; the number of seismic events was 5,204 on 6 October, 5,543 on 7 October, and 5,883 on 8 October. The Alert Level remained at 3 (on a scale of 1-4), and visitors and residents were not permitted to approach the volcano within a 2-km radius As of the 4th of October, CVGHM reported that new explosions occured this day. The volcano had been experiencing a very sharp increase in seismicity numbering over 6000-7000 a day (well above the background of 100-300 per day). A 2km exclusion zone was established around the island volcano. A satellite image acquired on 31 July 2011 showed a diffuse ash plume rising from Anak Krakatau and drifting W Based on information from CVGHM, the Darwin VAAC reported that on 12 January 2011 an eruption plume from Anak Krakatau rose to an altitude of 2.4 km (8,000 ft) a.s.l. and drifted SE. Meteorological clouds prevented observations of the area from satellite. On 15 January, a pilot observed a plume that rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted 18-28 km E.Based on analysis of satellite imagery, the Darwin VAAC reported that on 24 December 2010an ash plume from Anak Krakatau rose to an altitude of 2.4 km (8,000 ft) a.s.l. and drifted 65-75 km SE. The renowned Krakatau volcano lies in the Sunda Strait between Java and Sumatra. Collapse of the ancestral Krakatau edifice, perhaps in 416 AD, resulted in a 7-km-wide caldera. Remnants of this volcano formed Verlaten and Lang Islands; subsequently Rakata, Danan, and Perbuwatan volcanoes were formed, coalescing to create the pre-1883 Krakatau Island. Caldera collapse during the catastrophic 1883 eruption destroyed Danan and Perbuwatan volcanoes, and left only a remnant of Rakata volcano. The post-collapse cone of Anak Krakatau (Child of Krakatau), constructed within the 1883 caldera at a point between the former cones of Danan and Perbuwatan, has been the site of frequent eruptions since 1927. Live Webcam

Soputan volcano (Sulawesi) - CVGHM reported that seismicity at Soputan significantly decreased after the
eruption on 14 August until 7 September. White plumes rose at most 200 m above the crater during 14-18 August, up to 150 m above the crater during 19-28 August, and as high as 100 m above the crater during 29 August-7 September. The Alert Level was lowered to 2 (on a scale of 1-4) on 8 September. Visitors and residents were prohibited from going within a 4-km radius of the crater, a change from the 6-km restricted zone in place when the Alert level was at 3. As of the 14th of August, CVGHM reported that Mount Soputan emitted a new cloud of ash on Sunday morning, reaching 1 kilometer in height. The eruption started around 10 a.m. Sunday, plume of the the volcanic eruption was visible from the town of Tompaso district in Minahasa, close to the volcano ( video) - As of the 3rd of July 2011 the CVGHM reported that Mount Soputan in North Sulawesi province erupted at around 6:03 am (10:03 Sunday 3rd of July NZT) but people living in the sparsely populated area have not been evacuated.The volcano erupted in the morning with an important explosive activity which generated a volcanic plume 14 km high above the volcano. The ash cloud from the initial explosion/eruption drifted further to the south-west. The image confirms the subsiding activity of the volcano. Around midnight local time (18 hours after the first eruption), the volcano's activity subsided drastically.  The activity is ongoing with some limited isolated bursts of ash. the eruption has been centered around the crater with limited impact the the surrounding landscape . The Indonesian authorities are monitoring the eruption continuously and will order an evacuation if the volcano would change his erupting pattern. Some regional airports have been closed from the time of the eruption until the afternoon because of ash clouds. The recommended evacuation zone is set at a six-kilometre radius around the volcano but there's only forest in that range. The small Soputan stratovolcano on the southern rim of the Quaternary Tondano caldera on the northern arm of Sulawesi Island is one of Sulawesi's most active volcanoes. The youthful, largely unvegetated volcano rises to 1784 m and is located SW of Sempu volcano. It was constructed at the southern end of a SSW-NNE trending line of vents. During historical time the locus of eruptions has included both the summit crater and Aeseput, a prominent NE-flank vent that formed in 1906 and was the source of intermittent major lava flows until 1924. Last previous eruption occured in 2008. VSI website

Ranakah volcano (Flores) - CVGHM reported that throughout September and during 1-12 October 2011 diffuse white plumes rose 10-15 m above the Anak Ranakah lava dome. Plumes were not observed during 13-21 October. Starting on 1 July, seismicity had increased to a peak level on 15 August then declined through 20 October. Based on visual observations, seismicity, and deformation data, CVGHM lowered the Alert Level to 2 (on a scale of 1-4) on 22 October. Based on visual observations and seismic data analyses of the Anak Ranakah lava dome since December 2010, CVGHM raised the Alert Level on 26 August to 2 (on a scale of 1-4). During 26 August-7 September white plumes rose 5-10 m above the lava dome. Seismic activity continued to increase, prompting CVGHM to again raised the Alert Level, to 3, on 8 September.CVGHM reported that observers of Anak Ranakah, a lava dome that formed in 1987 at the base of the large older lava dome of Ranakah, noted white plumes rising up to 10 m high during January-24 August 2011. Seismicity initially increased in December 2010, but increased again during June-August. Based on visual observations and seismic data analyses, CVGHM raised the Alert Level to 2 (on a scale of 1-4). A new lava dome, named Anak Ranakah (Child of Ranakah) was formed in 1987 in an area without previous historical eruptions at the base of the large older lava dome of Gunung Ranakah. An arcuate group of lava domes extending westward from Gunung Ranakah occurs on the outer flanks of the poorly known Poco Leok caldera on western Flores Island. Pocok Mandosawa lava dome, at 2350 m the highest point on the island of Flores, lies west of Anak Ranakah.

Batu Tara volcano (Flores) - Based on analyses of satellite imagery, the Darwin VAAC reported that on 27
October an ash plume from Batu Tara rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted about 45 km W.
Based on analyses of satellite imagery, the Darwin VAAC reported that during 21-24 September ash plumes from Batu Tara rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted 37-65 km W, WNW, and NW. Based on analyses of satellite imagery, the Darwin VAAC reported that during 13-20 September ash plumes from Batu Tara rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted 25-75 km W, WNW, and NW. Based on analyses of satellite imagery, the Darwin VAAC reported that during 8-13 September ash plumes from Batu Tara rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted 37-65 km NW and W.Based on analyses of satellite imagery, the Darwin VAAC reported that during 23-30 August ash plumes from Batu Tara rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted 20-90 km N, NW, and W. The small isolated island of Batu Tara in the Flores Sea about 50 km north of Lembata (formerly Lomblen) Island contains a scarp on the eastern side similar to the Sciara del Fuoco of Italy's Stromboli volcano. Vegetation covers the flanks of Batu Tara to within 50 m of the 748-m-high summit. Batu Tara lies north of the main volcanic arc and is noted for its potassic leucite-bearing basanitic and tephritic rocks. The first historical eruption from Batu Tara, during 1847-52, produced explosions and a lava flow. The Current Colour Code for Batu Tara is ORANGE

Lewotobi volcano (Flores Island) - CVGHM raised the Alert Level for Lewotobi Lakilaki, one of two
stratovolcanoes composing Lewotobi, to 2 (on a scale of 1-4) on 22 September due to increased seismicity since 17 September and visual observations. Although no significant changes in the volcano were observed, diffuse white plumes rose 15 m above the crater. Visitors and residents were prohibited from going within a 1-km radius of Lewotobi Lakilaki. CVGHM reported that during 26-31 August seismicity at Lewotobi increased. Plumes of "smoke" rose 15-50 m above the Lewotobi Perampuan crater rim; no other significant changes were visibly apparent. Based on the seismic data, the Alert Level was raised to 2 (on a scale of 1-4) on 31 August. Visitors and residents were advised not to approach the volcano within 1 km of the Lewotobi Perampuan crater. The Lewotobi "husband and wife" twin volcano (also known as Lewetobi) in eastern Flores Island is composed of the Lewotobi Lakilaki and Lewotobi Perempuan stratovolcanoes. Their summits are less than 2 km apart along a NW-SE line. The conical 1,584-m-high Lewotobi Lakilaki has been frequently active during the 19th and 20th centuries, while the taller and broader 1,703-m-high Lewotobi Perempuan has erupted only twice in historical time. Small lava domes have grown during the 20th century in the crescentic summit craters of both volcanoes, which are open to the N. A prominent flank cone, Iliwokar, occurs on the E flank of Lewotobi Perampuan. (GVN/GVP)

Lewotolo volcano (Lomblen Island) - On 25 January CVGHM lowered the Alert Level for Lewotolo from 3 to 2 (on a scale of 1-4) based on decreased seismicity and visual observations during 5-15 January. During 5-15 January fumarolic plumes rose 200-500 m above the summit and incandescence was observed.
According to news articles, 500 people have evacuated their homes on 6 January because of increased activity at Lewotolo. Black smoke rose from the crater and rumbling sounds were reported. On 2 January CVGHM raised the Alert Level from 2 to 3 (on a scale of 1-4). CVGHM reported that white plumes rose 50-250 m above the summit of Lewotolo during the month of December. Seismicity increased on 31 December and intensified on 2 January 2012, the same day incandescence was observed. Based on visual and seismic observations, CVGHM raised the Alert Level from 1 to 2 (on a scale of 1-4) on 2 January, then later that day raised the Alert Level to 3. Anchoring the eastern end of an elongated peninsula that is connected to Lomblen Island by a narrow isthmus and extends northward into the Flores Sea, Lewotolo rises to 1,423 m. Lewotolo is a symmetrical stratovolcano as viewed from the N and E. A small cone with a 130-m-wide crater constructed at the SE side of a larger crater forms the volcano's high point. Many lava flows have reached the coastline. Historical eruptions, recorded since 1660, have consisted of explosive activity from the summit crater. (GVN/GVP)


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RUSSIA - Bezymianny volcano (Kamchatka)

December 27th, 2012

Seismic activity was mainly low last week. According to visual data, a strong and moderate gas-steam activity of the volcano was observed on January 20 and 24-26, clouds obscured the volcano in the other days of week. According to satellite data, a thermal anomaly over the volcano was noted on the satellite images all week.
According to visual data, a strong and moderate gas-steam activity of the volcano was observed on January 14 and 17, clouds obscured the volcano in the other days of week. According to satellite data, a weak thermal anomaly over the volcano was noted on the satellite images on January 17-18. According to visual data, a strong and moderate gas-steam activity of the volcano was observed on January 06-09 and 11, clouds obscured the volcano in the other days of week. According to satellite data, weak thermal anomaly over the volcano was noted on the satellite images all week. According to visual data, a strong and moderate gas-steam activity of the volcano was observed on January 02-05, clouds obscured the volcano in the other days of week. According to satellite data, weak thermal anomaly over the volcano was noted on the satellite images on December 30-31 and January 02-05, clouds obscured the volcano in the other days of week.Seismic activity was mainly low last week. According to visual data, a strong and moderate gas-steam activity of the volcano was observed on December 22-24 and 27-29, clouds obscured the volcano in the other days of week. According to satellite data, weak thermal anomaly over the volcano was noted on the satellite images on December 22-24 and 26-28, clouds obscured the volcano in the other days of week. According to visual data, a strong and moderate gas-steam activity of the volcano was observed on December 18-21, clouds obscured the volcano in the other days of week. According to satellite data, weak thermal anomaly over the volcano was noted on the satellite images on December 19-21, clouds obscured the volcano in the other days of week.According to visual data, a strong gas-steam activity of the volcano was observed on December 11, clouds obscured the volcano in the other days of week. According to satellite data, weak thermal anomaly over the volcano was noted on the satellite images on December 11-13, clouds obscured the volcano in the other days of week.According to visual data, a moderate gas-steam activity of the volcano was observed on December 03-08. (webcam) .Prior to its 1955-56 eruption, Bezymianny volcano had been considered extinct. Three periods of intensified activity have occurred during the past 3,000 years. The latest period, which was preceded by a 1,000-year quiescence, began with the dramatic 1955-56 eruption. That eruption, similar to the 1980 event at Mount St. Helens, produced a large horseshoe-shaped crater that was formed by collapse of the summit and an associated lateral blast. Subsequent episodic but ongoing lava-dome growth, accompanied by intermittent explosive activity and pyroclastic flows, has largely filled the 1956 crater. KVERT

RUSSIA - Sheveluch volcano ( Kamchatka)

January 27th, 2012

Seismic activity of the volcano was mainly low last week but it increased on January 22-23. According to visual data, a viscous lava flow continues to effuse into the explosive crater of 2010 eruption. Moderate fumarolic activity of the lava dome and sometimes hot avalanches from the lava flow were observing on January 25-26; clouds obscured the lava dome on the other days of week. A thermal anomaly was noting over the lava dome all week at satellite images. Ash plumes on the height about 16,400-19,700 ft (5-6 km) a.s.l. extended about 108 mi (174 km) to northeast of the volcano on January 23. According to visual data, moderate ash plumes occurred on January 14; a viscous lava flow continues to effuse into the explosive crater of 2010 eruption. Moderate fumarolic activity of the lava dome was observing on January 13-14 and 17-18. Sometimes hot avalanches from the lava flow were noting at video camera at night. A thermal anomaly was noting over the lava dome all week without January 16, at satellite images. According to visual data, a viscous lava flow continues to effuse into the explosive crater of 2010 eruption. Moderate fumarolic activity of the lava dome was observing all week without January 10. Sometimes hot avalanches from the lava flow were noting at video camera at night. A thermal anomaly was noting over the lava dome all week at satellite images.According to visual data, a viscous lava flow continues to effuse into the explosive crater of 2010 eruption. Moderate fumarolic activity was observing at the lava dome on December 30-31, and January 02 and 04; clouds obscured the volcano on the other days of week. A thermal anomaly was noting over the lava dome all week at satellite Images.Moderate seismic activity of the volcano was registering all week. According to visual data, a viscous lava flow continues to effuse into the explosive crater of 2010 eruption. Moderate fumarolic activity was observing at the lava dome on December 22-24; clouds obscured the volcano on the other days of week. According to satellite data, gas-steam plumes drifting about 18.6 mi (30 km) to the north and southeast of the volcano were noted on December 24 and 27, respectively. The summit of roughly 65,000-year-old Stary Sheveluch is truncated by a broad 9-km-wide late-Pleistocene caldera breached to the south. Many lava domes dot its outer flanks. Strong culmination explosive eruption of the lava dome of Sheveluch volcano occurred in 1993, 2001, 2004 and two in 2005. Live cam link

RUSSIA - Karymsky volcano (Kamchatka)

January 27th, 2012

Moderate seismic activity of the volcano continues; according to seismic data, possible ash plumes rose up to 9,840 ft (3.0 km) a.s.l. on January 19-21 and 25. According to satellite data, gas-steam plumes containing ash extending about 43.51 mi (70 km) to northwest of the volcano were noted on January 23. A thermal anomaly was registering over the volcano on January 21-24; clouds obscured the volcano in the other days of week.
according to seismic data, possible ash plumes rose up to 10,800 ft (3.3 km) a.s.l. last week. According to satellite data, a thermal anomaly was registering over the volcano on January 14-15; clouds obscured the volcano in the other days of week.According to satellite data, a thermal anomaly was registering over the volcano on January 05-11; weak ash plumes extending east and northeast about 25 mi 40 km of the volcano was detected on January 06-07 and 11. According to satellite data, a thermal anomaly was registering over the volcano all week; an ash cloud 10x2 km in size was detected to 34.7 mi (56 km) south southeast of the volcano on January 01. According to seismic data, possible ash plumes rose up to 16,400 ft (5.0 km) ASL all week. According to satellite data, a thermal anomaly was registering over the volcano on December 22-24 and 27-28, clouds obscured the volcano in the other days of week.Moderate seismic activity of the volcano continues; according to seismic data, possible ash plumes rose up to 13,500 ft (4.1 km) ASL all week. According to satellite data, gas-steam probable containing small amount of ash plumes were extending about 25 mi (40 km) to the south of the volcano were noted on December 20. A thermal anomaly was registering over the volcano on December 18-21.According to seismic data, possible ash plumes rose up to 13,500 ft (4.1 km) ASL on December 08-10 and 14. According to satellite data, weak ash plumes were extending about 99 mi (160 km) to the south-east from the volcano were noted on December 12-13. A thermal anomaly was registering over the volcano all week. According to satellite data, ash plumes were extending about 55.8 mi (90 km) to the east from the volcano were noted on December 03 and 07-08. A thermal anomaly was registering over the volcano all week. According to seismic data, possible ash plumes rose up to 12,500 ft (3.8 km) ASL all past week. A thermal anomaly was registering over the volcano on November 24, 28 and 30, and December 01 at satellite images.Moderate seismic activity of the volcano continues; according to seismic data, possible ash plumes rose up to 9,200 ft (2.8 km) ASL on November 19-22. According to satellite data, a thermal anomaly was registering over the volcano on November 18, 20 and 24 at satellite images. According to satellite data, ash plumes extended about 107 mi (172 km) to the east from the volcano on November 11; a thermal anomaly was registering over the volcano on November 11-12 at satellite images.Moderate seismic activity of the volcano continues; according to seismic data, possible ash plumes rose up to 11,500 ft (3.5 km) ASL last week. According to satellite data, the volcano was quiet or obscured by clouds all week. According to seismic data, possible ash plumes rose up to 14,760 ft (4.5 km) ASL on October 27-30 and November 01-02. According to satellite data, ash plumes extending for about 81 mi (130 km) to the south-east were observed on October 29-30. Karymsky, the most active volcano of Kamchatka's eastern volcanic zone, is a symmetrical stratovolcano constructed within a 5-km-wide caldera that formed during the early Holocene. The caldera cuts the south side of the Pleistocene Dvor volcano and is located outside the north margin of the large mid-Pleistocene Polovinka caldera, which contains the smaller Akademia Nauk and Odnoboky calderas. The latest eruptive period began about 500 years ago, following a 2300-year quiescence. Much of the cone is mantled by lava flows less than 200 years old. Historical eruptions have been vulcanian or vulcanian-strombolian with moderate explosive activity and occasional lava flows from the summit crater.

RUSSIA - Kliuchevskoy volcano (Kamchatka)

June 2nd, 2011

As of the 31st of May, KVERT reported that seismic activity of the volcano continues. According to visual and video data, ash plumes are raising up to 16, 400 ft (5.0 km) ASL and extending to the south-west from the volcano on May 29. The volcano was quiet on May 30, and obscured by clouds on May 31.Moderate seismic activity of the volcano continues but essentially decreased. Strong and moderate gas-steam activity of the volcano was observing on February 04-07; clouds obscured the volcano on the other days of week. According to satellite data, a very weak thermal anomaly was noted over the volcano on February 06-07. Gas-steam plumes extending about 20 km (12 mi) to the north-east from the volcano were noted on February 05 and 07. As of the 4th of February, KVERT reported that moderate seismic activity of the volcano continues and weak volcanic tremor was registering at the volcano all week. Strong and moderate gas-steam activity of the volcano was observing on January 27 and 30-31, and February 01-03. According to satellite data, a very weak thermal anomaly was noted over the volcano all week. Also moderate gas-steam activity was observing on January 24-27, on the other days the volcano was obscured by clouds. According to satellite data, a very weak thermal anomaly was noted over the volcano on January 22 and 26. According to satellite data, a very weak thermal anomaly was also noted over the volcano on January 13 and 16. Activity of the volcano decreased: gas-steam emissions were observing last week. Aerosol plumes could affect low-flying aircraft. Seismicity of the volcano was at background levels all week but weak volcanic tremor continues to registering at the volcano. According to visual data, strong gas-steam emissions from the volcano were observing on January 06-09. Clouds obscured the volcano on the other days of week. According to satellite data, a very weak thermal anomaly was registered over the volcano on January 07-09. As of the 7th of January, KVERT reported that seismicity of the volcano was at background levels all week but weak volcanic tremor continues to registering at the volcano. According to visual data, strong gas-steam emissions from the volcano were observing all week. According to satellite data, a very weak thermal anomaly was registered over the volcano all week.As of the 24th of December, KVERT reported that seismicity of the volcano was slightly above background levels on December 16-17, and did not exceed background levels on the other days of week. According to visual data, strong gas-steam emissions were observing on December 16-18, 20 and 23-24. Clouds obscured the volcano on the other days of week. A weak thermal anomaly over the volcanic crater was registered on satellite images on December 17-18 and 20-21. Kliuchevskoi flanks Kamen volcano to the SW and Ushkovsky volcano to the NW. More than 100 flank eruptions have occurred during the past roughly 3000 years . Live cam link

RUSSIA - Koriaksky volcano

November 14th, 2009

As of the 12th of November, the Kamchatkan Volcanic Eruption Response Team (KVERT) reported that during 30 October-6 November seismic activity from Koryaksky did not exceed background levels. Fumarolic activity was noted on 29 October and during 4-5 November. The Level of Concern Colour Code was lowered to Green. Fumarolic activity of the volcano continues and such activity is normal for the volcano. Last time there were ash plumes at the volcano on August 13th-27th. But strong gas-steam plumes could affect low-flying aircraft. Seismicity didn't exceeded background levels all week. Moderate fumarolic activity of the volcano was observing on October 29th and November 4th-5th. Clouds obscured the volcano in the other days of week. According to satellite data, the volcano was quiet last week. As of the 6th of November, the Kamchatkan Volcanic Eruption Response Team (KVERT) reported that fumarolic activity of the volcano continues and such activity is normal for the volcano.seismicity didn't exceeded background levels all week. Moderate fumarolic activity of the volcano was observing on October 29th and November 4th-5th. Clouds obscured the volcano in the other days of week. According to satellite data, the volcano was quiet last week. As of the 30th October, KVERT reported that seismicity didn't exceeded background levels all week, weak volcanic tremor was registering in the area of the volcano on October 24th-27th. Moderate fumarolic activity of the volcano was observing on October 23rd-25th and 28th-29th. Clouds obscured the volcano on October 26th-27th. According to satellite data, the volcano was quiet last week. Moderate fumarolic activity of the volcano was observed on October 17-22. According to satellite data, the volcano was quiet last week. Moderate fumarolic activity of the volcano sometimes with weak emissions of ash was observed on October 01-03 and 05-07. According to satellite data, a weak thermal anomaly was registering over the volcano on October 2nd. According to visual data, gas-steam plumes rose up to 3.7 km (12,100 ft) ASL on September 12-17. Aerosolic plumes extended >10 km (6 mi) to the eastern directions from the volcano. Clouds obscured the volcano in the other days of week. According to satellite data, the volcano was quiet. . According to visual data, gas-steam plumes raising up to 3.4 km (11,100 ft) ASL were observed on September 4th and 6th. Clouds obscured the volcano in the other days of week. According to satellite data, the volcano was quiet. Seismicity of the volcano didn't exceeded background levels all week but a volcanic tremor was registering on August 27th-28th and September 1st. According to visual data, gas-steam plumes raising up to 3.7 km (12,100 ft) ASL and extending to the different directions from the volcano were observed last week. According to satellite data, the volcano was quiet. According to visual data, gas-steam plumes containing ash raising up to 3.7 km (12,100 ft) ASL and extending to the different directions from the volcano were observed on August 26-27. According to satellite data, ash plumes extending >385 km (>239 mi) mainly to the eastern directions from the volcano were registered on August 20-27. As of the 21st of August, (KVERT reported that activity of the volcano continues. Seismicity was slightly above background levels last week. According to visual data, gas-steam plumes containing ash raising up to 3.5-4.2 km (11,500-13,800 ft) ASL and extending to the different directions from the volcano were observed on August 16th-20th. Before ash plumes the height of gas-steam plumes was about 3.5-5.0 km (11,500 - 16,400 ft) ASL on August 13th-16th. According to satellite data, ash plumes extending about 215 km (>133 mi) mainly to the eastern and western directions from the volcano were registered on August 16th-20th. According to satellite data, an ash plume extending >180 km (>112 mi) to the ESE from the volcano was registered on August 12th. According to satellite data, a thermal anomaly was registered on July 20th. According to satellite data, gas-steam plumes containing an ash extending for about 100 km (62 mi) to the NE from the volcano were noted on April 17-18 and 22nd. There was registered an SO2 signal (OMI data) for about 15 km (9 mi) from Koryaksky on April 20th. On 11 April, KVERT staff reported ashfall in Petropavlovsk-Kamchatsky (30 km S). Ash accumulated to 0.1-2.5 cm thickness near the Institute of Volcanology and Seismology (IVS) FED RAS. The Level of Concern Colour Code remained Orange. According to satellite data, aerosolic plumes containing ash extended about 225 km (140 mi) to the south-east from the volcano on March 25-26. Seismic activity of the volcano was above background levels on March 13th and at background levels during other days of the week. Aerosolic plumes containing small amount of ash raising up to 4.0 km (13,200 ft) ASL and extending to the eastern directions from the volcano were observed all week. As of the 6th of March, KVERT reported that during 3-4 March gas plumes containing a small amount of ash rose to an altitude of 3.7 km (12,100 ft) a.s.l. and drifted more than 200 km ENE. Ash deposits were seen at the summit. Ash deposits 1-2 mm thick accumulated in an area between Koryaksky and Avachinsky volcanoes. The Level of Concern Color Code was raised to Orange. A strong fumarolic activity of the volcano was observed on February 22-26. The volcano was obscured by clouds during other days. According to satellite data, an ash plume extending about 50 km (31 mi) and an aerosolic plume with ash to 200 km (124 mi) to the ENE from the volcano were observed on February 25th. During 6-7 January gas-and-steam plumes drifted SW. The Level of Concern Color Code was lowered to Yellow. As of the 2nd of January, the Kamchatkan Volcanic Eruption Response Team (KVERT) reported that weak explosive activity of the volcano continued. According to scientists, probably activities of the volcano will increase again. The activity of the volcano is dangerous for low-flying aircraft. Seismic activity of the volcano was at background levels: from 1 to 7 volcanic earthquakes were noting each day at the volcano. Possibly an episode of volcanic tremor were registered on December 30-31 and January 1st. According to visual data, gas-steam plumes possibly containing small amount of ash moves on the surface of north-western slope of the volcano on December 30-31. Clouds obscured the volcano in the other days. As of the 28th of December, KVERT informed that moderate explosive Volcanian type eruption of the volcano occured. Ash plumes raise about 4.0 km (13.200 ft) ASL and extended to the north-west from the volcano. No seismic data about this event by technical reasons. Gas-steam plumes containing small amount of ash were registering during daylight hours on the satellite images on December 23-25. Strong fumarolic activity were noted at the volcano from November, 2008. According to satellite data, on December 24th of December, at 23:34 UTC (NOAA 17, 4m5)) and 23:42 UTC ( TERRA MODIS, 31m32) a dense ash plume extended over 60 km (37 mi) and a poor ash plume extended 140 km (87 mi) to the northeast of the volcano. According to visual data by observers from Nalychevo valley, a dark column rose about 200-300 m from the vent of a fumarole on the northwestern flank of Koryaksky volcano on December 24. The fumarole is located about 3.0 km ASL. Observers heard a boom from the volcano at night. According to seismic data (KB GS RAS), only 2 earthquakes were registered on December 23 on the depth of 5.0 km under the volcano. KVERT continues to monitor Koryaksky volcano. The colour code at Koryaksky is currently at YELLOW. The large symmetrical Koryaksky stratovolcano is the most prominent landmark of the NW-trending Avachinskaya volcano group, which towers above Kamchatka's largest city, Petropavlovsk. Erosion has produced a ribbed surface on the eastern flanks of the 3456-m-high volcano; the youngest lava flows are found on the upper western flank and below SE-flank cinder cones. No strong explosive eruptions have been documented during the Holocene. Extensive Holocene lava fields on the western flank were primarily fed by summit vents; those on the SW flank originated from flank vents. Lahars associated with a period of lava effusion from south- and SW-flank fissure vents about 3900-3500 years ago reached Avacha Bay. Only a few moderate explosive eruptions have occurred during historical time. Koryaksky's first historical eruption, in 1895, also produced a lava flow.

RUSSIA - Gorely volcano

January 27th, 2012

Seismic activity of the volcano remains some heightened. The volcano was obscured by clouds all week. A thermal anomaly was registering over the volcano on January 23 at satellite images.A thermal anomaly was registering over the volcano on January 17 at satellite images.Seismic activity of the volcano remains some heightened. According to visual data, a strong and moderate gas-steam activity of the volcano was observed on January 06-11. A thermal anomaly was registering over the volcano on January 06-08 at satellite images. Seismic activity of the volcano was increasing on January 02-03: about 20-30 seismic events were registered into the volcanic edifice. According to visual data, a strong and moderate gas-steam activity of the volcano was observed all week. A thermal anomaly was registering over the volcano on December 30 and January 01-02 at satellite images. According to visual data, a strong and moderate gas-steam activity of the volcano was observed on December 22-23 and 29. A big thermal anomaly was registering over the volcano on December 29. According to visual data, a strong and moderate gas-steam activity of the volcano was observed on December 17-21. A thermal anomaly was registering over the volcano on December 20.A thermal anomaly over the volcano was noted at satellite images on December 02 and 07. According to visual data, a moderate gas-steam activity of the volcano was observed on November 27-28 and 30; the volcano was obscured by clouds on the other days of week. A thermal anomaly over the volcano was noted at satellite images on November 24 and 27-28. According to visual data, a moderate gas-steam activity of the volcano was observed on November 20 and 23-24; the volcano was obscured by clouds on the other days of week. A thermal anomaly over the volcano was noted at satellite images on November 24. According to visual data, a moderate gas-steam activity of the volcano was observed on November 13-14; the volcano was obscured by clouds on the other days of week. A weak thermal anomaly over the volcano was noted at satellite images on November 13. According to visual data, a moderate gas-steam activity of the volcano was observed on November 06-07; the volcano was obscured by clouds on the other days of week. A weak thermal anomaly over the volcano was noted at satellite images on November 05. According to visual data, a moderate gas-steam activity of the volcano was observed from October 29 till November 01; the volcano was obscured by clouds on the other days of week. A weak thermal anomaly over the volcano was noted at satellite images on October 31 and November 01-02. A weak thermal anomaly over the volcano was noted at satellite images on October 21-25. According to visual data, the volcano was quiet or obscured by clouds all week. A weak thermal anomaly over the volcano was noted at satellite images on October 15 and 18. Moderate gas-steam activity of the volcano was observed on October 07-09; clouds obscured the volcano on the other days of week. A weak thermal anomaly over the volcano was noted at satellite images on October 11-12. A weak thermal anomaly over the volcano was noted at satellite images on October 05. Moderate gas-steam activity of the volcano was observing on September 22-23 and 26-27, clouds obscured the volcano on the other days.Moderate gas-steam activity of the volcano was observing on September 20-22, clouds obscured the volcano on the other daysModerate gas-steam activity of the volcano was observing on September 10-14, clouds obscured the volcano on the other days. According to satellite data, a thermal anomaly was registering over the volcano on September 04-05.Moderate seismic activity of the volcano continues and a volcanic tremor was registering at the volcano all week. Moderate gas-steam activity of the volcano was observing all week. According to satellite data, a thermal anomaly was registering over the volcano on August 26 and 29. According to satellite data, a thermal anomaly was registering over the volcano on August 19 and 22-23. According to visual data previous week, the Lake continues to exist into the active crater of volcano. Red heat of rocks is observing into the fumarole vent. Moderate gas-steam activity of the volcano was observing on August 13 and 16-17. According to visual data on August 06-09, the Lake continues to exist into the active crater of volcano. Blocks of ice on Lake surface were melting. Red heat of rocks is observing into the fumarole vent. Moderate gas-steam activity of the volcano was observing all week. A thermal anomaly was registering over the volcano on August 04.Moderate seismic activity of the volcano continues and weak volcanic tremor was registering at the volcano all week. According to visual data, a moderate fumarole activity was observing on July 24-27, the volcano was obscured by clouds on the other days of week. A thermal anomaly was registering over the volcano on July 22 and 24-25. According to visual data, a moderate fumarole activity was observing on July 20, the volcano was obscured by clouds on the other days of week. A thermal anomaly was registering over the volcano on July 14. Weak volcanic tremor was registering at the volcano all week from 7th to 14th of July. According to visual data by volcanologists on July 07-08, a red incandescence continues to observing into the new fumarole on the bottom of Active crater. The volcano was quiet or obscured by clouds this week.. According to satellite data, a weak thermal anomaly over the volcano was registered on June 28. Clouds obscured the volcano during other days. According to satellite data, a weak thermal anomaly over the volcano was registered on June 17. Clouds obscured the volcano during other days. According to visual data, a red incandesce was observing into the new fumarole vent into the Active crater on June 11-12. The lake into Active crater was absence. A weak thermal anomaly over the volcano was registering on June 12-13. Clouds obscured the volcano on the other days.Moderate seismic activity of the volcano continues and weak volcanic tremor was registered at the volcano all week. A weak thermal anomaly over the volcano was registering on June 03-04. Gas-steam plume extended about 15 km to the north from the volcano. Clouds obscured the volcano on the other days. An amplitude of volcanic tremor slightly increased on May 18. According to visual data, the volcano was quiet or obscured by clouds this week. A weak thermal anomaly over the volcano was registering on May 14. Seismic and thermal activity of the volcano remains high. This ongoing unrest may eventually lead to an explosive eruption. Aerosol plumes from the volcano could affect low-flying aircraft. Moderate seismic activity of the volcano continues and weak volcanic tremor was registered at the volcano all week. According to visual and satellite data, the volcano was quiet or obscured by clouds this week. Moderate seismic activity of the volcano continues and weak volcanic tremor was registered at the volcano all week from 29th of April to 5th of May. According to satellite data on May 05, a weak thermal anomaly was registered over the volcano and gas-steam plume extended about 9 mi (15 km) to the west from the volcano.As of the 28th of April, KVERT reported that moderate seismic activity of the volcano continues and weak volcanic tremor was registered at the volcano all week. According to visual data, a moderate gas-steam activity was observed on April 24. The lake into the active crater of the volcano disappeared. According to satellite data, a weak thermal anomaly was registered over the volcano on April 22-24 and 27.Moderate seismic activity of the volcano continues and weak volcanic tremor was registered at the volcano all week. According to satellite data, a thermal anomaly was registered over the volcano on April 15. Clouds obscured the volcano during other days. Moderate gas-steam activity of the volcano was observed on April 10. Clouds obscured the volcano during other days. Gorely volcano, one of the most active in southern Kamchatka, consists of five small overlapping stratovolcanoes constructed along a WNW-ESE line within a large 9 x 13.5 km caldera. The caldera formed about 38,000-40,000 years ago accompanied by the eruption of about 100 cu km of tephra. The massive Gorely complex contains 11 summit and 30 flank craters, some of which contain acid or freshwater crater lakes; three major rift zones cut the complex. Another Holocene stratovolcano (peak 1082) is located on the SW flank of Gorely. Activity during the Holocene was characterized by frequent mild-to-moderate explosive eruptions along with a half dozen episodes of major lava extrusion. Early Holocene explosive activity, along with lava flows filled in much of the caldera. Quiescent periods became longer between 6000 and 2000 years ago, after which the activity was mainly explosive. About 600-650 years ago intermittent strong explosions and lava flow effusion accompanied frequent mild eruptions. Historical eruptions have consisted of vulcanian and phreatic explosions of moderate volume.(GVN) - Gorely webcam

RUSSIA - Kizimen volcano

January 27th, 2012

Moderate seismic activity of the volcano continues. Video data and satellite imagery showed that the lava flow continues to effusing on the eastern volcanic flank. Hot avalanches accompany the lava flow effusion. Strong gas-steam activity of the volcano was noting at video camera. A big thermal anomaly was registering over the volcano all week at satellite images. Strong gas-steam plumes drifting about 93 and 18.6 mi (150 and 30 km) to the north and southeast of the volcano were noted on December 24 and 27, respectively. Video data and satellite imagery showed that the lava flow continues to effusing on the eastern volcanic flank. A big thermal anomaly was registering over the volcano all week. A gas-steam plume extended about 40.3 mi (65 km) to the south of the volcano was noted at satellite images on December 20.KVERT reported an increasing seismicity of Kizimen last week. Series of strong seismic events were registered on December 13 in period 19:47-20:28 UTC. According to interpretation by KBGS RAS staff, possibly ash explosions were height about 24,600 ft (7.5 km) a.s.l. Video observation of the volcano showed that hot avalanches from the left side of the lava flow began to forming from 16:00 UTC on December 13, and continues possibly at present. Volumes of hot avalanches changed and sometimes large pyroclastic flows were observed. A large pyroclastic flows with co-ignembrite clouds were observed in period 20:20-22:10 UTC on December 13. Ash plumes (generating by pyroclastic flows) rose about 16,400-19,700 (5-6 km) a.s.l. No explosions were noted for all time on December 13-14. Strong gas-steam plume don't elevated to high up the summit of the volcano and moved to the south-east. Ashes from pyroclastic flows mixed with gas-steam and gas-ash plumes on the height about 9,840 ft (3 km) a.s.l. extending 93 mi (about 150 km) from the volcano were noting at satellite images on December 13-14. The large lava flow continues to effuse on the eastern and north-eastern volcanic flanks - a big thermal anomaly was registering over the volcano all week at satellite images.Seismic activity of the volcano some increased last week: about 100-140 seismic events were registering each day; a magnitude of volcanic tremor was about 0.2-0.6 mkm/s. Video camera was not working last week by technical reasons. The large lava flow continues to effuse on the eastern and north-eastern volcanic flanks - a big thermal anomaly was registering over the volcano all week at satellite images. According to report by pilots of local airlines (the data from AMC Elizovo), strong gas-steam plumes extended from the volcano on November 27-28. An elevation of plumes was about 16,400 ft (5 km) ASL. The large lava flow continues to effuse on the eastern and north-eastern volcanic flanks - a big thermal anomaly was registering over the volcano all week at satellite images.According to video data, a strong and moderate gas-steam activity of the volcano was observed on November 20 and 22-24. Clouds obscured the volcano on the other days of week. The large lava flow continues to effuse on the eastern and north-eastern volcanic flanks - incandescences of the crater of the volcano was noting sometimes in a dark time. A big thermal anomaly was registering over the volcano all week at satellite images. According to video data, a strong and moderate gas-steam activity of the volcano was observed on November 10 and 13-14. Clouds obscured the volcano on the other days of week. The large lava flow continues to effuse on the eastern and north-eastern volcanic flanks - incandescences of the crater of the volcano was noting in a dark time on November 13-14. A thermal anomaly was registering over the volcano on November 11-14 and 17, at satellite images; clouds obscured the volcano on the other days of week.Moderate seismic activity of the volcano was registering previous week: a magnitude of volcanic tremor was 0.3-0.4 mcm/s. According to video data, a strong and moderate gas-steam activity of the volcano was observed on November 04-09. Clouds obscured the volcano on November 03, and partly on the other days in week. The large lava flow continues to effuse on the eastern and north-eastern volcanic flanks - incandescences of the crater of the volcano was noting in a dark time on November 02-03 and 06-09. A thermal anomaly was registering over the volcano all week at satellite images.Moderate seismic activity of the volcano was registering last week: numbers of volcanic earthquakes were changing from 12 to 36; a magnitude of volcanic tremor was 0.3 mcm/s. According to video data, a gas-steam activity of the volcano was observed from October 28 till November 02. Clouds obscured the volcano on the other days of week. The large lava flow continues to effuse on the eastern and north-eastern volcanic flanks - incandescences of the crater of the volcano was noting in a dark time all week. A thermal anomaly was registering over the volcano all week at satellite images.Moderate seismic activity of the volcano was registering last week: numbers of volcanic earthquakes were changing from 105 on October 21 to 30 on October 24; a magnitude of volcanic tremor was mainly 0.3-0.5 mcm/s. According to video data, there was noting a small pyroclastic flow on the north-eastern volcanic flank on October 20, and later ash covered volcanic edifice. Gas-steam activity of the volcano was observed on October 20-21 and 23-26. The large lava flow continues to effuse on the north-eastern volcanic flank - incandescences of lava flow and the crater of the volcano were noting in a dark time all week. A thermal anomaly was registering over the volcano all week at satellite images. Moderate seismic activity of the volcano was registering last week: numbers of volcanic earthquakes were changing from 22 to 60; a magnitude of volcanic tremor was mainly 0.3-0.5 mcm/s. According to video data, a result of ashfalls were noted on October 14-15: an ash covered snow at all volcanic flanks. Probably power gas-steam plumes contained ashes on October 14. A large lava flow continues to effuse on the north-eastern volcanic slope; strong fumarole activity was observing on October 13-16. A thermal anomaly was registering over the volcano all week at satellite images. Previous past week seismic activity of the volcano continued to decreasing last week: numbers of volcanic earthquakes reduced from beginning to end of week from 500 to 100; a magnitude of volcanic tremor was 0.3-0.5 mcm/s last week. According to video data, a large lava flow continues to effuse on the north-eastern volcanic flank; strong fumarole activity was observing all week. A thermal anomaly was registering over the volcano all week at satellite images Seismic activity of the volcano was already decreasing to October 05-06: numbers of volcanic earthquakes reduced from 1300 to 500-700; a magnitude of volcanic tremor - from 2.0 to 0.4-0.5 mcm/s. According to video data, a large lava flow continues to effuse on the north-eastern volcanic flank; strong fumarole activity was observing on September 29-30 and October 03-06. Clouds obscured the volcano in the other days of week. A thermal anomaly was registering over the volcano all week at satellite images but a temperature of anomaly began to decreasing. The summit of Kizimen consists of overlapping lava domes, and blocky lava flows descend the flanks of the volcano, which is the westernmost of a volcanic chain north of Kronotsky volcano. The 2376-m-high Kizimen was formed during four eruptive cycles beginning about 12,000 years ago and lasting 2000-3500 years. The largest eruptions took place about 10,000 and 8300-8400 years ago, and three periods of long-term lava dome growth have occurred. The latest eruptive cycle began about 3000 years ago with a large explosion and was followed by lava dome growth lasting intermittently about 1000 years. An explosive eruption about 1100 years ago produced a lateral blast and created a 1.0 x 0.7 km wide crater breached to the NE, inside which a small lava dome (the fourth at Kizimen) has grown. A single explosive eruption, during 1927-28, has been recorded in historical time. GVN/GVP
Islands

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NEW ZEALAND - White island volcano

October 24th, 2008

A White Island's Crater Lake has continued to rise since December 2007, after being almost completely evaporated in late October 2007. By 23 October the lake was reported to have risen 15 m and was beginning to affect the geothermal features on the Main Crater floor. New springs formed on the floor and old springs flowed again. The lake temperature remained hot at 57 degrees Celsius and the color had changed to light green, reflecting a decrease in suspended sediment. High-temperature fumaroles (101-103 degrees Celsius) were located on the S side of the Main Crater floor. Steam, gas, and mud emissions had increased from the largest vent during the previous few weeks. The Alert Level remained at Level 1 (on a scale of 0-5), indicating signs of volcano unrest.Live cam link - other webcam

NEW ZEALAND - Ruapehu volcano

May 4th, 2011

On 2 May, GeoNet reported that the temperature of Ruapehu's summit Crater Lake continued to slowly cool and was about 30 degrees Celsius, down from a peak of 41 degrees in March. The lake level remained below the overflow level and no earthquakes had been located within 10 km of the Crater Lake for two weeks. The Aviation Colour Code was lowered to Green and the Volcanic Alert Level remained at 1 (signs of volcano unrest). On 5 April 2011, GeoNet reported that the temperature of Ruapehu's summit Crater Lake had been high for a sustained period and was currently between 38 and 39 degrees Celsius. The highest temperature since unrest began in October 2010 was 41 degrees Celsius, measured on 1 March. The report also noted that during the previous few weeks there was an increase in carbon dioxide gas emissions, increased seismicity, and changes in Crater Lake water chemistry. The unrest prompted GeoNet to raise the Aviation Colour Code although the Volcanic Alert Level remained at 1 (some signs of volcano unrest). PREVIOUS NEWS - As of the 18 th of September 2008, Geonet bulletin (INGS) reported this day that Ruapehu appears to be entering a new heating cycle. The Crater Lake temperature has risen to 22°C this month, from 16°C in August, a change accompanied by some volcanic tremor. Between October 2007 and June 2008 the temperature varied between 34°C and 37°C. Sulphur dioxide and carbon dioxide levels in the volcano's plume are also showing an upwards trend, consistent with the rising temperature within the Crater Lake. There is nothing unusual about any of this, because cyclic activity in the Crater Lake is very common at Ruapehu. The volcano in central North Island, last erupted on Sept. 25 2007, spitting 2 metre (6 feet) boulders distances of up to 2 kms (1.5 miles). Ruapehu's elevated alert level has not been changed, but IGNS reported on Tuesday that activity within the mountain was greater, with high levels of gas spewing out, a warmer than average crater lake and ongoing volcanic tremors. The volcano remains in a status of unrest and the possibility of further activity remains. If further eruptions occur, they may occur without warning. Ruapehu, one of New Zealand's most active volcanoes, is a complex stratovolcano constructed during at least 4 cone-building episodes dating back to about 200,000 years ago. The 110 cu km dominantly andesitic volcanic massif is elongated in a NNE-SSW direction and is surrounded by another 100 cu km ring plain of volcaniclastic debris, including the Murimoto debris-avalanche deposit on the NW flank. A series of subplinian eruptions took place at Ruapehu between about 22,600 and 10,000 years ago, but pyroclastic flows have been infrequent at Ruapehu. A single historically active vent, Crater Lake, is located in the broad summit region, but at least five other vents on the summit and flank have been active during the Holocene. Frequent mild-to-moderate explosive eruptions have occurred in historical time from the Crater Lake vent, and tephra characteristics suggest that the crater lake may have formed as early as 3000 years ago. Lahars produced by phreatic eruptions from the summit crater lake are a hazard to a ski area on the upper flanks and to lower river valleys. Ruapehu Live cam

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PAPUA - NEW GUINEA - Ulawun

volcanoJune 2nd, 2011 RVO reported that during 23-27 May gray ash plumes rose above Ulawun's summit crater. Fine ash fell in Ubili and Ulamona on the NW flank on 26 May.RVO reported that during 19-22 May gray-to-brown ash plumes rose above Ulawun and fine ash fell on the NW and W flanks. Weak, fluctuating incandescence was observed on 22 May. RVO reported that during 13-14 and 17 May gray-to-brown ash plumes rose above Ulawun. On 17 May the emissions were forceful for a short time and booming noises were reported. Light ashfall was reported in areas between Ubili in the NW and Voluvolu in the NE. RVO reported that during 1-9 May diffuse white plumes rose from Ulawun and Real-time Seismic-Amplitude Measurement (RSAM) values ranged between 70 and 100. During 9-10 May RSAM values distinctly increased, fluctuated, and peaked at 1300 units before declining back to 100 units. During this time local residents heard booming. On 10 May grey-to-brown ash plumes were observed. RVO reported that mild activity from Ulawun that began in May 2010 continued during 1 January-28 February 2011. The activity was characterized by brown-to-gray ash plumes that rose less than 500 m and produced fine ashfall to the SE. Sulfur dioxide plumes drifted SE on 5 and 31 January. During 23-26 February gray ash plumes occasionally drifted NE, SW, and NW. The symmetrical basaltic-to-andesitic Ulawun stratovolcano is the highest volcano of the Bismarck arc, and one of Papua New Guinea's most frequently active. Ulawun volcano, also known as the Father, rises above the north coast of the island of New Britain across a low saddle NE of Bamus volcano, the South Son. The upper 1000 m of the 2334-m-high Ulawun volcano is unvegetated. Historical eruptions date back to the beginning of the 18th century. Twentieth-century eruptions were mildly explosive until 1967, but after 1970 several larger eruptions produced lava flows and basaltic pyroclastic flows, greatly modifying the summit crater.

PAPUA-NEW GUINEA - Rabaul volcano

August 20th, 2011

RVO reported that white vapor plumes rose from Rabaul caldera's Tavurvur cone during 15-19 August. No volcano-related seismicity was recorded. The rate of uplift from GPS measurements on Matupit Island had increased from the end of July. RVO reported a decline in frequency of ash emission from Rabaul caldera's Tavurvur cone during 9-12 August, and no distinct explosions were detected. Ash-rich plumes rose 1 km above the crater and drifted NW, causing ashfall in Rabaul town (3-5 km NW) and in areas between Toliap (10 km NW) and Tavui. Seismicity was very low, consisting of sub-continuous volcanic tremor associated with the ash emissions and some small discrete low-frequency earthquakes. Ash emissions ceased on 12 August. During 13-15 August white vapor plumes rose from the crater. RVO reported that white vapor plumes rose from Rabaul caldera's Tavurvur cone during 1-3 August. An explosion on 3 August produced a gray ash plume that rose 1 km above the crater and drifted NNW. Sustained emissions of pale-gray ash continued for about an hour afterwards. In addition, ash deposited at the former airport was re-suspended and blown NW into the E part of Rabaul town (3-5 km NW) and towards Namanula hill (3 km W). Seismicity was very low, although two periods of harmonic tremor on 2 August and the explosion and ash emissions on 3 August were detected. During 4-5 August gray ash emissions periodically continued, punctuated by a few large and notable explosions. Ash plumes from the explosions rose 1 km above the crater and drifted N and NW producing fine ashfall in the E part of Rabaul town, Namanula Hill, and further downwind towards Tavui Point. Moderate seismicity consisting of low-frequency earthquakes, explosions, and volcanic tremors with variable durations was detected. During 5-9 August activity increased, characterized by an increased frequency and duration of ash emissions and more explosions. About 34 explosions were recorded between 5 and 8 August. Ash-rich clouds that rose 1.5 km above the crater drifted NW causing ashfall in most parts of Rabaul town and in areas between Toliap and Nonga (10 km NW). GPS measurements on Matupit Island continued to show long-term inflation; about 10-11 cm of uplift had been recorded since August 2010. RVO reported that white vapor occasionally tinted blue rose from Rabaul caldera's Tavurvur cone during 1-28 July 2011. Dull incandescence emanated from a small caved-in vent on the floor of the crater. The start of an ash eruption on 29 July was marked by an emergent low-frequency tremor and slowly rising gray ash plumes. One explosion on 30 July possibly produced light ashfall to the NW. Seismic data indicated forceful degassing on 1 August. Based on analyses of satellite imagery, the Darwin VAAC reported that on 29 March 2011 an ash plume from Rabaul caldera's Tavurvur cone rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted more than 53 km NW. The low-lying Rabaul caldera lies on the tip of the Gazelle Peninsula at the NE end of New Britain.

PAPUA - NEW GUINEA - Manam volcano

October 20th, 2011

Based on analysis of satellite imagery, the Darwin VAAC reported that on 18 October ash plumes from Manam rose to an altitude of 3.7 km (12,000 ft) a.s.l. and drifted 150-170 km NW. PREVIOUS NEWS - RVO reported that the summit area of Manam was obscured by atmospheric clouds on most days during 1-19 August. When the summit was clear to viewers on the mainland, 15-20 km away from Manam, both vents were
emitting white vapor plumes. Main Crater produced light-gray ash clouds during 13 and 17-18 August, and bright, steady incandescence was visible on most clear nights. Weak incandescence was visible from Southern Crater on some nights. People living on the island reported occasional noises from both craters on 3 and 11 August. Seismicity during the reporting period was dominated by volcanic tremors. Discrete high-frequency volcano-tectonic earthquakes were also recorded. RVO noted that high-frequency volcano-tectonic earthquakes are not very common for Manam. An electronic tiltmeter located about 4 km SW from the summit craters continued to show inflation towards the summit area. Based on analysis of satellite imagery, the Darwin VAAC reported that during 18-21 August ash plumes rose to altitudes of 1.8-2.1 km (6,000-7,000 ft) a.s.l. and drifted 45-90 km NW and W. RVO reported that during 5-6 January low roaring from Manam's South Crater was heard and weak but steady crater incandescence was observed at night. Diffuse blue vapor was emitted from South Crater on 6 January. During 6-8 January white vapor rose from Main Crater and incandescence from both craters was observed at night. Diffuse brown ash plumes occasionally rose from South Crater on 7 January. The next day the Alert Level was lowered from Stage 3 to Stage 2. During 8-9 January Main Crater emitted white vapor and South Crater produced occasional gray ash plumes that drifted to the SE part of the island. Emissions from Main Crater turned to gray on 10 January. White-to-blue vapor plumes rose from South Crater. Both craters were incandescent at night during 8-10 January. The 10-km-wide island of Manam, lying 13 km off the northern coast of mainland Papua New Guinea, is one of the country's most active volcanoes.

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TONGA - Hunga Ha'apai islands

March 22nd, 2009

Local pilot reported that at 1015 on 21 March the island was covered by weather clouds, the crater was not visible, and there was no vertical plume; haze was again below an inversion layer at 1.5 km altitude. No eruptions were seen during the 15 minutes the island was visible on the return flight around 1250. However, steaming continued, with the plume rising to 1.8 km altitude. A new eruptive episode was reported by Tongatapu airport observers at 1409 on 21 March that sent an ash plume 800 m high. As of the 20th of March,Wellington VAAC reported that eruptive activity at Hunga Tonga-Hunga Ha'apai appears to have declined somewhat over the last 12 hours. The VAAC advisory, based on pilot observations and satellite imagery, reported no more active eruptions steaming 1800 metres high, with white and wispy ash haze extending to large areas ENE blw 5000ft [below 1500 metres]‘. An earlier advisory (17:58 GMT - 19th March) reported frequent eruptions and ash clouds to FL130 (13000 feet, 4000 metres), with a plume extending 300 miles (480 kilometres) ENE. At 01:30 GMT today NASA's Aqua satellite captured a MODIS image which showed only a small plume extending less than 10 kilometres ENE of the volcano (from the NASA MODIS). As of the 18th of March, the Global Volcanism Network (GVN) reported that a new eruption in Tonga was documented on 16 or 17 March by observers flying near the area. Preliminary description and coordinates suggest that the eruption is from Hunga Tonga-Hunga Ha'apai islands ( approx. coordinates S 20º 27' 73? W 175º 25' 61? given by the pilots). Residents said the steam and ash column first appeared on Monday morning, after a series of earthquakes were felt in the capital, Nuku'alofa. Press reported that spectacular columns spewed out of the sea about 6 miles (10 kilometers) from the southwest coast off the main island of Tongatapu. According to Tonga GeologicaI Service it was likely the underwater eruption was taking place to the west of the low-lying twin volcanic islands of Hunga Tonga and Hunga Ha'apai, within sight of Nuku'alofa. Preliminary report and photos.The small islands of Hunga Tonga and Hunga Ha'apai cap a large seamount located about 30 km SSE of Falcon Island. The two linear andesitic islands are about 2 km long and represent the western and northern remnants of a the rim of a largely submarine caldera lying east and south of the islands. Hunga Tonga and Hunga Ha'apai reach an elevation of only 149 m and 128 m above sea level, respectively, and display inward-facing sea cliffs with lava and tephra layers dipping gently away from the submarine caldera. A rocky shoal 3.2 km SE of Hunga Ha'apai and 3 km south of Hunga Tonga marks the most prominent historically active vent. Submarine eruptions were reported here in 1912 and 1937 and from a fissure 1 km SSE of Hunga Ha'apai in 1988. ***********************************************************************************************************************

Mariannes islands - Pagan volcano

February 3rd, 2012

Low-level gas-and-steam plumes from Pagan were observed in satellite imagery during 20-27 January. Based on information from the Honolulu MWO, satellite imagery, and a pilot observation, the Washington VAAC reported gas emissions and a possible light-brown ash plume drifting E on 30 January. The Aviation Color Code remained at Yellow and the Volcano Alert Level remained at Advisory.
Previously, Northern Mariana Islands status report noted that clear to partly-cloudy satellite images showed a persistent gas-and-steam plume drifting from Pagan during 25 November-2 December 2011. The Aviation Color Code remained at Yellow and the Volcano Alert Level remained at Advisory. Northern Mariana Islands status report noted that during 26 August-2 September low-level vapor plumes from Pagan, possibly containing minor amounts of ash, were visible in satellite imagery. Reports from people on Pagan Island also indicated intermittent low-level but diffuse ash emissions and trace amounts of ashfall on parts of the island. The Aviation Color Code remained at Yellow and the Volcano Alert Level remained at Advisory. A Northern Mariana Islands status report noted that on 7 July a low-level gas-and-steam plume with possible fine ash was detected in satellite imagery as well as noted by observers on the island. Low-level gas-and-steam plumes had been detected in satellite imagery during the previous few weeks. The Aviation Color Code remained at Yellow and the Volcano Alert Level remained at Advisory. On 22 February, the Aviation Color Code and the Volcano Alert Level for Pagan were lowered to Unassigned. With the exception of a faint steam-and-gas plume observed on 24 January, no unusual activity at Pagan volcano had been detected in satellite imagery during the previous six weeks. Pagan is not monitored with ground-based geophysical instrumentation; the only source of information is satellite observations and occasional reports from island visitors.The 570-m-high Mount Pagan at the NE end of the island rises above the flat floor of the northern caldera, which probably formed during the early Holocene. South Pagan is a 548-m-high stratovolcano with an elongated summit containing four distinct craters. Almost all of the historical eruptions of Pagan, which date back to the 17th century, have originated from North Pagan volcano. The largest eruption of Pagan during historical time took place in 1981 and prompted the evacuation of the sparsely populated island. Last know eruption occured in 2006.

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ANTARCTICA - Erebus Volcano

March 1st, 2009

As of the 1st of March 2009, the Mt. Erebus Volcano Observatory (MEVO) reported that Antarctica's Mt. Erebus continues with a molten lava lake and vapour emissions. It may be covered with glaciers, but they do little to cool the volcano's molten core. As of the 1st of August 2007, the Mt. Erebus Volcano Observatory (MEVO) was reported that Mt. Erebus has frequent Strombolian eruptions. Infrequent ash eruptions. Rare lava flows confined to inner crater. Notable features are: Persistent convecting phonolite lava lake. Persistent low-level eruptive activityAccording to the Mt. Erebus activity log, several "small- to medium-sized" eruptions occurred during 12-18 October 2005, with a "very large" eruption occurring on 14 October. The eruption sizes were based on comparisons of seismic data for known Erebus eruptions. Mt. Erebus, the southern most volcano in the world, still continues to be the most active volcano in Antarctica. Mt. Erebus (3794 meters above sea level) is classified as a polygenetic stratovolcano. The composition of the current eruptive activity on Mt. Erebus is anorthoclase-phyric tephriphonolite and phonolite, which constitute the bulk of exposed lava flow on the volcano. The oldest eruptive products from Mt. Erebus consist of relatively undifferentiated and non-viscous basanitic lavas that form the low, broad platform shield of the Erebus edifice. Slightly younger basanites and phonotephrite lavas crop out on Fang Ridge, an eroded remnant of an early Erebus volcano and at other isolated locations on the flanks of the Mt. Erebus edifice. Lava flows of more viscous phonotephrite, tephriphonolite and trachyte are erupted after the basanites. The upper slopes of Mt. Erebus are dominated by steeply dipping (~30°) tephriphonolite lava flows with large scale flow levees. A conspicuous break in slope at approximately 3200 meters is a summit plateau representing a caldera. The summit caldera itself is filled with small volume tephriphonolite and phonolite lava flows. In the center of the of the summit caldera is a small, steep-sided cone composed primarily of decomposed lava bombs and a lag deposit of anorthoclase crystals. It is within this summit cone that the active lava lake continuously degasses and periodically erupts. Mt. Erebus located on Ross Island, Antarctica is the world’s southern-most active volcano. Discovered in 1841 by James Ross, it is one of only a very few volcanoes in the world with a long-lived (decades or more) lava lake. Scientific research, sponsored by the U.S. National Science Foundation (NSF) since began the early 1970’s had included basic study of the petrology and geophysics of the volcano, the eruptive history, activity and degassing behavior of the lava lake, and the overall impact of the volcano on the Antarctica and global environment. Research on Mt. Erebus has been primarily conducted by scientists in the Department of Earth and Environmental Science and the Bureau of Geology and Mineral resources at the New Mexico Institute of Mining and Technology. Information from : MEVO - Live cam link

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Vanuatu - Aoba volcano (Ambae)

July 13th, 2011

On 11 July the Vanuatu Geohazards Observatory noted that there had been recent increases in activity from Aoba and that local earthquakes were volcanic.According to the analysis of data collected by the Vanuatu Meteorology and Geohazards Department (VMGD) in 12 July, the Ambae volcano have had small successive explosions in July 10th 2011 from 6:45 to 7:15pm. Though the volcano seemed quite in July 12th the data collected shows that volcano earthquakes still exist on this island. This means that this volcano activity still remains but moderate to weak. The trend of the activity of this volcano is not clear at this state. It is possible to be quiet but it is also likely that this volcano continue to go through small explosions from time to time. Satellite images collected by the Ozone Monitoring Instrument showed sulfur dioxide emissions. Observations on 4 June revealed that small explosions had been occurring from the crater lake and were accompanied by local ashfall around the crater. Some villagers in the N and W parts of the island had observed the explosions. The Vanuatu Volcano Alert Level (VVAL) remained at 1 (on a scale of 0-4). Aoba, also known as Ambae, is a massive 2500 cu km basaltic shield volcano that is the most voluminous volcano of the New Hebrides archipelago. A pronounced NE-SW-trending rift zone dotted with scoria cones gives the 16 x 38 km island an elongated form. A broad pyroclastic cone containing three crater lakes is located at the summit of the Hawaiian-style shield volcano within the youngest of at least two nested calderas, the largest of which is 6 km in diameter. Post-caldera explosive eruptions formed the summit craters of Lake Voui (also spelled Vui) and Lake Manaro Ngoru about 360 years ago. A tuff cone was constructed within Lake Voui about 60 years later. The latest known flank eruption, about 300 years ago, destroyed the population of the Nduindui area near the western coast.

VANUATU - Gaua - Mt. Garet volcano

October 20th, 2011

Based on a hazards assessment during 17-18 October, the Vanuatu Geohazards Observatory reported that Gaua had been emitting ash since September. Ash fell on western parts of the island. The Alert Level remained at 1 (on a scale of 0-4).The data collected by the monitoring system of Gaua volcano shows the existence of earthquakes caused by volcanic activity in August 2011. The OMI satellite images clearly shows that Gaua volcano has gone through some degassing in 17, 27, and 28 September 2011. This means that the Gaua volcano activity is ongoing. The local authorities have reported, in October 10th, the ashfall on the north eastern and the western part of Gaua. With this report the Alert Level of Gaua volcano remains at level 1 according to the Vanuatu volcanoes Alert Systems . However this alert Level may change after the Geohazards team risk assessment on this volcano in the coming days. Previous year news : At the current time of December, the Gaua volcano activity is low and has been low since September 2010. Latest observations on Gaua indicates that the vegetations near the volcano vent and the ones exposed to the trade winds on the western side of the island which were burnt by acid rains are now growing again. This means that the Gaua volcano is emitting less gas. This is also proven by the data recorded by the monitoring stations that clearly shows the decreasing number of counts of volcano triggered earthquakes since September 2010 As of the 24th of June, the Vanuatu Geohazards Observatory (VGO) reported that based on information from the Vanuatu Geohazards Observatory, the Wellington VAAC reported that during the 16th-19th of June ash plumes from Gaua rose to an altitude of 3 km (10,000 ft) a.s.l. On the 19th of June the plume drifted more than 90 km W. As of the 7th of May, Geohazard reported that field observations of Gaua volcano have shown that there has been moderate activity during the month of April through to the beginning of May. There has been significant emissions of ash and gas over the island of Gaua. This strong gas emission has caused the vegetations around the crater of the volcano to dry up as well as the areas that are exposed to dominant winds, especially from the North western to the South Western coast of the Island. Also during this month of April, mud flows were witnessed by the geo-hazards technical team at Ontar in West Gaua. Volcanic seismic data recorded by the station at Metsalewon in the North East, and the station in the South East both show that tremors have been occurring more frequent with time, since the beginning of the year till the present. As of the 22nd of April, the Vanuatu Geohazards Observatory (VGO) reported that the situation at Gaua is worsening. Ash from the current eruption is contaminating water and food supplies on the island. Authorities are planning on evacuating 3,000 people from the island if the eruption that started in 2009 gets worse, but there has already been significant ash fall, mudflows and explosions. As of the 7th of April, the analysis of data collected from the monitoring network of Gaua volcano since October 2009 indicates the existence of volcanic tremor. The OMI satellite images also show the abundance of gases emitted from this volcano daily. Field observations reported by the Geohazards officer in Gaua confirmed significant change of activity with ticker and higher emissions of ash columns. Since last week (end of march/beginning of April 2010) the ash plumes height dwell between 7000 and 10000 feet every day. Field reports also stated that the explosion sounds could be heard from the villages daily. Moreover, starting from the 3rd of April 2010 the volcanic bombes projections from Gaua volcano could be observed from all the coastal villages from the north to the south of the island with reports of the ashfall. As of the 29th of January, Geo-hazards Vanuatu reported that the volcanic activity on Gaua has changed significantly during the month of January. More gas has been emitted since 16 January, followed by multiple explosions with thicker and darker ash plume. This plume of ash and gas was being expelled to about more than 3000 meters high and carried by the wind to surrounding villages in the south and west. Strong strombolian activity was evident on the 24th of January 2010 as villagers were able to observe its projections. These signs indicate that the level of magma is rising. Very strong explosions have been heard and seen from the coastal villages of East Gaua this morning, January 29th 2010. Due to the current activity, the level of water and the rate of river flow from the waterfall and outlets were observed to have risen from 20 to 30cm since January 22nd. This occurrence is possibly due to the disturbance within the Lake Letas which is feeding the river due to the rising activity. Water from water thanks in the eastern coast is becoming acid from the acid rains. This means that there can be greater threats posed given the occurrence of volcanic explosions. As of the 13th of January 2010, Geo-Hazards Vanuatu reported that the continuous ash emission activity of the Gaua volcano that begun on Monday 14th December 2009 with the significant emissions of ashes is still ongoing. This was accompanied by explosions heard from the villages on the 29th of December 2009. This eruptive phase is different from previous activities with thicker and darker plumes (see photos). These changes reflect the evolution of the source (alimentation) of the volcano. Ash falls continue to persist in the western part of Gaua and with the changes in the direction of the wind; it is possible that ash falls may also be experienced in the eastern part of the island. Chemical analysis of the ashes that fell and were collected in October, which was carried out by York University in England, have indicated that there is a high concentration of chemicals which are hazardous to the human health within these ash particles from Gaua. More analysis will be coming up on the new deposits. The latest OMI satellite images clearly show the persistence of significant flux of gases being emitted from Gaua volcano. As of the 27th of November, the Geo-hazards Officer who is responsible for the Gaua volcano monitoring works on Gaua has confirmed the big explosion of the Gaua volcano in November 18th 2009 at 2pm. This explosion has been followed by very thick and high emissions of ash columns that were covering the areas exposed to trade winds in the West. Volcano-seismic data recorded by the monitoring station based in east Gaua shows the increase in volcano activity signals starting from October 25th. Until present, the data shows that the activity of Gaua volcano remains significant. With this trend, it is recommended that the Alert Level of the volcano be remained at level 2 according to the Vanuatu volcano Alert Levels (VVAL) while Geo-hazards is carrying out a very close monitoring with the IGNS counterparts. The danger persists in the red and yellow colour zones of the hazard map, especially the risks of ash falls and mudflows in the zone 1, zone 2 and zone 3 of the revised hazards map. According to news release more than 300 villagers were evacuated on Thursday 26th of November after an eruption started from the volcano and spewing smoke and ash onto the island and villages around. Residents were loaded onto fishing boats and shipped to the far side of Gaua island after the volcano. Also, according to Vanuatu's National Disaster Management Office they're evacuating people to the other side of the island. The Red Cross is providing water containers and purification tablets for the villagers, who have been hit by respiratory problems and diarrhoea caused by the volcano's pungent sulphur fumes. The evacuees will have to stay away from their villages until the volcano subsides, he said. The area has been put on the second highest alert level. No more information was reported directly from VGO yet. Previously, as of the 13th of October VGO (Vanuatu Geohazards Observatory) latest bulletin reported that after the assessment of the geohazards team on Gaua volcano from 3-7 October 2009, it is confirmed that Mont Garet volcano is going through an eruptive phase starting from the 27th of September 2009. Seismic records of the seismic station installed on Gaua show that many explosions occurred on Gaua volcano. Volcanic gas flux measurements on October 3rd show that 3000 tons of sulfuric dioxide is released from this volcano each day, this means that a significant quantity of magma is degassing from Gaua volcano. The lake letas, localised close to the Mont Garet volcano, is one of the biggest crater lake of South Pacific, its volume reachs 800 million cubic meters which is drained out through the river of the Waterfall. With this information, the Alert level of this volcano is now raised to Level 2 on the Vanuatu Volcano Alert Level (VVAL). This means that this volcano is going through a minor eruption. It is not recommended to approach the volcano. The danger remains in the red zone area on the hazard map including all the river outlets in Gaua, especially the river of waterfall (see Hazard map). With the related alert level, a level of response from the community is required (see attached Community Disaster response plan). Geohazards is doing its best with the limited resources available to continue monitoring this volcano. As of the 6th of october, local New Zealand information reported that volcanologists in Vanuatu are closely monitoring the Gaua volcano to consider whether to move its alert to level two. A senior vulcanologist at the geohazards department, Douglas Charley, reported his team has recorded more activity since last night. Very late yesterday the team started to observe an increase of a high volcanic high frequency. The level remains at one and the team will be trying to observe this until the next 48 hours. If activity will increasing further, Alert level will be putting to level two.Douglas Charley says they have one monitoring station in the field, but are now requesting more to get more reliable data. As of the 1st of october 2009, the national authorities of the republic of Vanuatu from the the Vanuatu Department of Geology Mines and Water Resources have issued an alert (at the lowest level of one , on a scale of 1-5) for Gaua volcano island, also known as Santa Maria Island located the northern part of the archipelago. The volcano has been showing signs of activity for the last two weeks, with accounts of repeated explosions and ash and gas emission. Local inhabitants have reported large quantities of smoke being produced by the volcano, a strong smell of sulphur and some contamination of local water and food supplies. About 2000 people live on the island. The roughly 20-km-diameter Gaua Island, also known as Santa Maria, consists of a basaltic-to-andesitic stratovolcano with an 6 x 9 km wide summit caldera. Small parasitic vents near the caldera rim fed Pleistocene lava flows that reached the coast on several sides of the island; several littoral cones were formed where these lava flows reached the sea. Quiet collapse that formed the roughly 700-m-deep caldera was followed by extensive ash eruptions. Construction of the historically active cone of Mount Garat (Gharat) and other small cinder cones in the SW part of the caldera has left a crescent-shaped caldera lake. The symmetrical, flat-topped Mount Garat cone is topped by three pit craters. The onset of eruptive activity from a vent high on the SE flank of Mount Garat in 1962 ended a long period of dormancy. Last know significative activity occures in 1982 (GVN/GVP)

VANUATU - Ambrym volcano

June 28th, 2011

As of the 27th of June, the data collected by the Vanuatu Meteorology and Geohazards Department from the
Ambrym volcano monitoring network shows that this volcano activity remains with daily significant degassing and occasional explosions are occurring in the crater. Field assessments conducted on this volcano proved that the level of lava lakes in all volcano vents is high and that volcanic gas emitted daily could cause damage to the environment and water in the villages. Reports from the villages during the month of June confirm that minor ash falls and acid rains that burn vegetations could be experienced in some villages from the west, the
south to the east of Ambrym Island.Ambrym, a large basaltic volcano with a 12-km-wide caldera, is one of the most active volcanoes of the New Hebrides arc. A thick, almost exclusively pyroclastic sequence, initially dacitic, then basaltic, overlies lava flows of a pre-caldera shield volcano. The caldera was formed during a major Plinian eruption with dacitic pyroclastic flows about 1900 years ago. Post-caldera eruptions, primarily from Marum and Benbow cones, have partially filled the caldera floor and produced lava flows that ponded on the caldera floor or overflowed through gaps in the caldera rim. Post-caldera eruptions have also formed a series of scoria cones and maars along a fissure system oriented ENE-WSW. Eruptions have apparently occurred almost yearly during historical time from cones within the caldera or from flank vents. However, from 1850 to 1950, reporting was mostly limited to extra-caldera eruptions that would have affected local populations.

VANUATU - Yasur volcano ( Tanna island)

June 15, 2011

On 13 June, the Vanuatu Geohazards Observatory reported that activity from Yasur decreased during the previous week after a brief period of high activity with significant explosions and ashfall. Even though Strombolian activity occasionally ejected bombs that fell around the crater, explosions had become slightly weaker and less frequent. The Alert Level was lowered to 2 (on a scale of 0-4).Following the assessment done by the Geohazards team on the 31 th May and 01 st   June, Yasur volcano has maintained its high activity with the strong explosions and ashes/bombs emissions from all the three active vents. The increasing activity of the Yasur volcano since May 2011 led us to upgrade the hazard rating of this volcano at Alert Level 3 starting from June 01, 2011.On 12 May 2011, the Vanuatu Geohazards Observatory reported that, based on information collected by the Vanuatu Meteorology and Geohazards Department, satellite imagery showed strong degassing from Yasur during the previous week. Residents living close to the volcano reported persistent strong explosions that were heard and felt on 12 May. The Vanuatu Volcano Alert Level (VVAL) remained at 2 (on a scale of 0-4). Update past year : 10th of June 2010 - Observations and assessments on the Yasur volcano during the past week week have indicated that Yasur's volcanic activity has decreased after a brief period of high activity with significant explosions and ash falls at the end of May 2010. Explosions have become less frequent yet constant strombolian activity with occasional ejections of lava bombs still occur around the volcano. Therefore with these indications the Alert Level of Yasur volcano is now decreased to Level 2 on the Vanuatu Volcano Alert Level (VVAL) . Visitors to the volcano are still advised to observe the volcano from safe distance away from the vent. It is advisable that visitors and tourist agencies must carefully consider this information given, to avoid the risks and dangers of the volcano. As of the 27th of May, Geohazard Vanuatu reported the increasing activity of the Yasur volcano since January 2010 led us to upgrade the hazard rating of this volcano at Alert Level 3 starting from May 27, 2010 .  Therefore the access to the volcano is now closed and its 500 m surrounding zone is strictly prohibited. Yasur volcano is currently undergoing moderate to large eruption with strong explosions ejecting volcanic bombs reaching the view points for visitors and the parking area with the significant ash fall in the villages nearby. High risk of volcanic projections remains in the red color Zone and threats of ash fall in parts of the yellow color zone that are exposed to trade winds that Following the assessment done by the Geohazards team on the 26th and 27th April, Yasur volcano has maintained its high activity with the strong degassing and ash emissions from all the three active vents and falling on most parts of the island from the east to the west. Fresh volcanic bombs have fallen around the crater rim; few of them have even reached the ash plain and the parking area. Explosions could be heard and viewed from the villages. Around 5 volcanic bombs have already fallen on the observation point B since beginning of April. Tour operators and local population have confirmed that the activity remains very important since the beginning of April. OMI pictures and the seismic data collected from the monitoring station confirmed this important activity with the strong degassing and very explosive activity to date Following the observations of the Geo-hazards team on in March 8th 2010 and the analysis of the volcano-seismic data recorded by the monitoring network of this volcano, it is confirmed that the activity of this volcano is increasing since January 2010, as indicated in the satellite images. This is also proven by the activity of all the three active vents and the recent volcanic bombs that fell on visitors' observation path. Under these circumstances, the Alert Level for Yasur volcano is raised to LEVEL 2 according to the Vanuatu Volcanoes Alert Levels (VVAL) . This means that eruptions are moderate and danger close to the volcano, within parts of Red Zone of the Hazard map. Thus approaching the volcano could be dangerous; it would be safer to view the yasur volcano from the parking area to avoid the volcano impact. Visitors and tourism agencies are advised to consider this information until the next alert is released. Previously, as of the 12th of August 2009, John Seach reported that eruptive activity continues at Yasur volcano in Vanuatu. During a visit to the volcano from 1-3 August, John Seach observed Strombolian explosions ejecting lava to a height of 300 m above the vent. Ash emissions were lower than normal, which allowed good views into the crater. One vent was active in the northern crater, and two vents active in the southern crater. As of the 1st of March 2009, Yasur volcano continues to erupt many times per hour as it has done so for at least 800 years. Previously, as of the 1st of October, mainly from reports from colleague, John Seach of Australia, reports that Yasur is still currently erupting. Strombolian and mild Vulcanian eruptions continue at Yasur volcano. Three main active vents are visible inside the summit crater. Incandescent lava explosions reached 250 m above the crater, accompanied by loud explosions. Projectiles were observed falling on the crater rim, 170 m from the vents. As of the 9th of April 2008, mainly from reports of John Seach , reported that a major earthquake (magnitude 7.6) hit southern Vanuatu today at 2346hrs local time. The earthquake was located east of the South New Hebrides Trench and 97 km SW of Yasur volcano. The Joint Australian Tsunami Warning Centre said there was no tsunami threat. The main earthquake was preceded by a large and two medium sized earthquakes; magnitude 6.5, 5.9, and 4.9. Yasur is the closest active volcano to the earthquake epicentre and is currently erupting. As of the 1st of April, activity has been almost continuous at the Yasur volcano in Vanuatu. As of the 26th of March, the Darvin Volcanic Ash Advisory (DVAAC) has reported that Strombolian and mild Vulcanian eruptions continue at Yasur volcano. Three main active vents are visible inside the summit crater. Incandescent lava explosions reached 250 m above the crater, accompanied by loud explosions. On 7-8th March, ash emissions increased at Yasur producing ashfall over villages within 4 km of the crater. Projectiles were observed falling on the crater rim, 170 m from the vents. Previous information from IRD reported that a new cycle of important activity has began at the end of June 2004. Its the fifth cycles of strong activity since the beginning of the permanent monitoring in 1993. This activity produced important ashfalls ( several millimeters as far 4 km distance of the volcano). Main eruptive activity occurred from the Crater A with strombolian explosions. Height has been estimated estimated to some 300 m high above the crater rim. Sulphur dioxide measurements (SO2) made between 11-17 of July 2004 with mini Doas spectrometer reaches average values of 1000 tonnes per day (500 tonnes per day in April 2004). Information from Michel Lardy (IRD Noumea) and DGMWR (Vanuatu) Yasur is one of the world's most active volcanoes. Previous informations from IRD reported that a new cycle of important activity has began at the end of June 2004. Its the fifth cycles of strong activity since the beginning of the permanent monitoring in 1993. This activity produced important ashfalls ( several millimeters as far 4 km distance of the volcano). Main eruptive activity occured from the Crater A with strombolian explosions. Height has been estimated estimated to some 300 m high above the crater rim. Sulphur dioxyde measurements (SO2) made between 11-17 of July 2004 with mini Doas spectrometer reaches average values of 1000 tons per day (500 tons per day in April 2004). Information from Michel Lardy (IRD Noumea) and DGMWR (Vanuatu)Previous significative information (September 2002) reported an increasing level of activity at Yasur since October 2001 and the volcanic quake of August 29, 2002 (about 3:00 pm local time), led local volcanologist to upgrade the hazard rating to Alarm Level 3. Access to the volcano was closed.The August 29 quake, magnitude 6 was strongly felt by the inhabitants of the whole district around the volcano (White Sands, Port Resolution, …). This was the first time since the seismic station was installed in October 1992 that a shock of such magnitude was recorded (see graphs below). Elders of the Yasur district confirm that such a quake had not been experienced within living memory.Two new seismological monitoring stations are about to be installed, to complement the existing alarm system installed 2 km from Yasur and the Isangel station. At this time, evacuation of the roughly 6000 inhabitants of the district has not been considered. Information bulletins will be broadcast by Radio Vanuatu to keep the population concerned informed of new developments. Yasur's activity follows a long volcanic history in the southeastern part of the island , whose main phases, over approximately the last 10,000 years, have produced: 1/ lava flows; 2/ extensive glowing ash flows that covered the entire region from Kwamera to Waisisi, and 3/ the construction of another small volcanic cone, the Ombus. Yasur volcano lies over a large and shallow (less than 10 km from the surface) magmatic chamber whose center is located between Port-Resolution and Sulfur Bay; thus, the possibility of a major eruption within a century or a millennium cannot be ignored. Such an eruption, however, would be preceded by numerous earthquakes. Should this happen, evacuation of the local population toward the west coast, the central districts and the north of the island would have to be carried out rapidly. Informations from :M.Lardy (IRD Noumea)