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NEWS Highlight today : eruption is still continuing at low levels at the Pavlof volcano - Aleutian islands - U.S.A. ( report below )- |
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ECUADOR - Guagua
Pichincha volcano January 2nd, 2013 No recent events occured since september 2010. 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 May 22nd, 2013 IG reported that during 15-20 May seismicity at Tungurahua remained at a moderate level and then decreased on 21 May. Visual observations were often limited due to cloud cover; steam plumes were observed rising from the crater on 17 and 19 May. A slight amount of ash fell in Choglontus (SW) on 15 May, and small lahars traveled down the Bilbao (W), Pingullo (NW), and La Pampa (S) on 20 May. IG reported that although cloud cover often prevented observations of Tungurahua during 8-14 May, ash plumes were observed almost daily. Seismicity remained at a moderate level. Explosions occasionally vibrated structures nearby and at the Tungurahua Observatory (OVT) in Guadalupe (14 km N). Strombolian activity was observed on most nights ejecting blocks sometimes 500 m above the crater; blocks that fell onto the flanks rolled as far as 1 km. During 9-10 May lava fountains rose 700 m above the crater. During 8-11 May ash plumes rose 1-2.5 km and drifted SW, W, and NW, producing ashfall in El Manzano (8 km SW), Choglontus (SW), Quero (20 km NW), Mocha (25 km WNW), Pillate (8 km W), Tisaleo (29 km NW), and Penipe on 8 and 10 May, and in Santa Fe de Galán, Mocha, Sabañag (15 km WNW), Tisaleo, and Quero (20 km NW) on 11 May. Ashfall was reported in Quero on 12 May. The next day explosions generated ash plumes that rose 2-3 km and drifted NW and W, producing ashfall in El Manzano. Roaring and sounds resembling rolling blocks were reported. On 14 May ash fell in Choglontus, El Manzano, and Mocha. Previously, IG reported that although cloud cover often prevented observations of Tungurahua during 1-7 May ash plumes were observed almost daily. Seismicity remained at a moderate level, although it increased on 4 May. On 1 May an explosion and rolling blocks were heard, and ashfall was reported in El Manzano (8 km SW). The next day steam-and-ash plumes rose 1-1.5 km above the crater and drifted W. Ashfall was reported in Cevallos (23 km NW), Tisaleo (29 km NW), Quero (20 km NW), and Mocha (25 km WNW). During 2-4 May Strombolian activity was observed at night. On 3 May several explosions produced ash plumes that rose 2-3 km above the crater and drifted N and NW. Ash fell in Juive (7 km NNW), Runtún (6 km NNE), Pondoa 8 km N), Baños (8 km N), Patate (NW), Pelileo (8 km N), Ambato (31 km NW), Cevallos, and at the Tungurahua Observatory (OVT) in Guadalupe (14 km N). On 4 May explosions rattled windows in Baños, and ash plumes rose 1-1.5 km and drifted N and NW. Large lahars traveled down the La Pampa drainage on the S flank, while other lahars traveled down the Vazcún, Juive, and Mandur drainages on the N and NW flanks. Explosions on 5 May rattled windows in Ventanas, Pondoa, and Runtún. An ash plume rose 2 km and drifted W. Ashfall was again reported in Cevallos, Tisaleo, Quero, and Mocha. A pyroclastic flow descended the NW flank 2 km. On 6 May ash plumes drifted SW and ashfall was reported in Cevallos, Tisaleo, Quero, Mocha, Pillate (8 km W), Choglontus (SW), and El Manzano. The next day ash plumes rose 3 km and drifted SW. Ashfall was reported in Sabañag (15 km WNW), Chazo, Ilapo, and Riobamba (30 km S). 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 ********************************************************************************************************************* ECUADOR - Reventador volcano May 14th, 2013 IG reported that during the morning of 8 May incandescence from
Reventador's crater was observed in addition to steam-and-ash plumes that
rose 1 km above the crater and drifted NW. Cloud cover prevented *************************************************************************************************************************** |
Tungurahua volcano 1999 - H. Gaudru |
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MONTSERRAT - Soufriere Hills volcano - West-Indies May 18th, 2013 Reports for the
period from 5th of February 2013 to 17th of May 2013 - Activity at the Soufrière Hills Volcano is still low. The seismic network recorded two rockfalls and five volcano-tectonic this week from 10th to 17th of May. Sulphur-dioxide measurements gave an average flux of 373 tonnes/day with a maximum of 553 and a minimum of 137 tonnes/day. The seismic network recorded three rockfalls, three volcano-tectonic earthquakes and one long-period earthquake this week from 3rd to 10th of May. Sulphur-dioxide measurements gave an average flux of 313 tonnes/day with a maximum of 435 and a minimum of 160 tonnes/day. Measurements were only possible on three days this week because of adverse wind conditions. The seismic network recorded three volcano-tectonic earthquakes this week from 26th of April to 3rd of May. Sulphur-dioxide measurements gave an average flux of 379 tonnes/day with a maximum of 466 and a minimum of 254 tonnes/day. The wind has been mainly towards the north and north-east since the night of 1/2 May. This has blown the volcanic plume over inhabited areas and the smell of volcanic gases has been noticeable at times. The seismic network recorded three volcano-tectonic earthquakes the previous week from 19th to 26th of April. Sulphur-dioxide measurements gave an average flux of 366 tonnes/day with a maximum of 535 and a minimum of 181 tonnes/day. There have been no good views of the dome for over a month now. Reports from helicopter pilots suggest that most of the large slab on the eastern side of the dome is now gone; removed by the pyroclastic flow on 28 March 2013. As of the 19th of April, MVO reported that activity at the Soufrière Hills Volcano is still low. The seismic network recorded two rockfalls and four volcano-tectonic earthquakes during the week from 12th to 19th of April. Sulphur-dioxide measurements gave an average flux of 556 tonnes/day with a maximum of 1155 and a minimum of 271 tonnes/day. Past week 5th to 12th of April, the seismic network recorded no seismic events related to the volcano this week. Sulphur-dioxide measurements gave an average flux of 325 tonnes/day with a maximum of 585 and a minimum of 186 tonnes/day. MVO reported that during 22-29 March activity at the Soufrière Hills lava
dome was at a low level. A pyroclastic flow traveled down the Tar River
Valley (E) at about 0500 on 28 March. The flow was not observed directly,
but the deposits indicated that it traveled halfway down the valley, 1-1.5
km from the dome. There were no reports of ashfall; any ash was probably
blown over Plymouth and out to sea. The source of the flow was not known
due to cloud cover, but was likely from the failure a large slab that had
been slowing moving away from the dome. Heavy rainfall during the evening
of 28 March generated large lahars in several valleys around the volcano,
including in the Belham Valley (NW). These started at about 1900 and lasted
for several hours. The Hazard Level remained at 2 (on a scale of 1-5). Activity at the Soufrière Hills Volcano is still low.The seismic network recorded one rockfall and three volcano-tectonic earthquakes this week from 15th to 22nd of March.Sulphur-dioxide measurements were possible on only three days this week, giving an average flux of 359 tonnes/day with a maximum of 540 and a minimum of 258 tonnes/day. There appear to have been no changes in the large slab recently observed to be peeling away from the dome above the Tar River Valley. The slab is now estimated to have dimensions of 80 by 60 by 4-6 metres. If this slab falls as a single block it will produce a large pyroclastic flow in the Tar River Valley, safely away from populated areas. previously , the seismic network recorded one rockfall this week from 8th to 15th of March.Sulphur dioxide measurements were possible on only three days this week, giving an average flux of 251 tonnes/day with a maximum of 264 and a minimum of 227 tonnes/day. During a helicopter inspection on 8 March 2013, we observed a large fissure in the cliff on the eastern side of the dome, part of which has existed since 2007. This fissure is the result of slow cooling and erosion of the dome. It is parallel to the cliff face and is estimated to be two metres wide, suggesting that a large slab is slowing peeling away from the dome. If this slab falls as a single block it will probably produce a moderate-to-large pyroclastic flow in the Tar River Valley, safely away from populated areas The seismic network recorded one rockfall, two volcano-tectonic earthquakes and one hybrid event this week from 1st to 8th of March.Sulphur dioxide measurements for the week gave an average flux of 368 tonnes/day with a maximum of 552 and a minimum of 213 tonnes/day. Variable winds blew the volcanic plume over inhabited areas for much of the week, particularly the first half, and the smell of volcanic gases was very noticeable at times. There has been no visible emission of ash from the volcano this week. MVO has received some reports of ash, but these could not be verified. The seismic network recorded one volcano-tectonic earthquake the past week from 22nd of February to 1st of March. Sulphur dioxide measurements for the week gave an average flux of 503 tonnes/day with a maximum of 1078 and a minimum of 312 tonnes/day. Variable winds blew the plume over inhabited areas on Thursday 28 February and the small of volcanic gases was noticeable at times. Past week, activity at the Soufrière Hills Volcano wasstill low. The sulphur-dioxide flux has returned to typical levels. The seismic network recorded three rockfalls this week. Sulphur dioxide measurements for the week gave an average flux of 442 tonnes/day with a maximum of 566 and a minimum of 236 tonnes/day. These are similar to the levels measured before the activity that occurred between 3 and 6 February. Previous week, activity at the Soufrière Hills Volcano was low, although the sulphur-dioxide flux remained elevated following the activity between 3 and 6 February. The seismic network recorded one rockfall and one volcano-tectonic earthquake this week from 8th to 15th 2013.Sulphur dioxide measurements for the week gave an average flux of 910 tonnes/day with a maximum of 1236 and a minimum of 575 tonnes/day. An elevated level of flux has been observed ever since the activity that occurred between 3 and 6 February. Previous week, activity was alsol low, although there was a slight increase between 3 and 6 February. This involved VT earthquakes, an elevated gas flux and possibly light venting of ash. This type of activity has been observed on several occasions since the end of extrusion on 11 February 2010 and this week's was the most intense since the ash-venting episode on 23-25 March 2012. The seismic network recorded one rockfall, 25 volcano-tectonic earthquakes and two hybrid events this week from 1st to 8th of February. The VT earthquakes occurred mainly in four brief swarms, at 10:20 pm on 3 February, at 9:15 am and 9:50 pm on 4 February and at 6:20 am on 5 February (all local time). The second swarm was the most intense. One of the hybrid events occurred at the end of the second swarm and the other was an isolated event. Sulphur dioxide measurements for the week gave an average flux of 929 tonnes/day with a maximum of 2381 and a minimum of 273 tonnes/day. The flux was not steady, with peaks of 962, 1266 and 2381 on 1, 4 and 6 February respectively. The last of these is the highest daily value since the ash-venting episode on 23-25 March 2012. After the second, largest, VT swarm on 4 February, there were increases in the temperatures of several fumaroles inside the 11 February 2010 collapse scar, as observed using a handheld thermal infra-red camera at MVO, 5.7 km away. There was a further increase, as well as some loud roaring sounds, around the time of the third swarm. It is likely that the activity included minor ash venting from a large fumarole in the floor of the collapse scar as fresh ash deposits were observed adjacent to this fumarole on the morning of 5 February. All fumaroles had returned to background levels of activity and temperature by later that day. Montserrat Volcano Observatory - View
latest NOAA satellite image of Montserrat ( every 30 mn) |
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MEXICO - Popocatepetl volcano May 22nd , 2013 At 0028 on 17 May another strong explosion ejected incandescent tephra 1.5
km from the crater, and generated an ash plume that rose over 4 km and
drifted NE. Later that day plumes of vapor and gas rose 1 km and drifted
SW. During an overflight on 18 May volcanologists observed a crater 200 m
wide and 40 m deep in the dome's surface; the material was likely excavated
by the explosions during 14 and 16-17 May. The rest of the dome was covered
with rock fragments. Gas-and-ash plumes rose 500 m and drifted SW. MEXICO - Colima volcano April 7th, 2013 As of the 6th of April, the summit lava dome showed some collapses. (video). Following more than one year without activity, an explosion occurred on 6th of January 2013 generating a volcanic plume that rose to about 2500 m above the summit crater, then quickly drifted toward the small town of Atenquique located 20 km East of the volcano. (video). 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 ********************************************************************************************************************** GUATEMALA - Fuego volcano May 22nd, 2013 INSIVUMEH reported that during 16-17 May white plumes rose 300 m from
Fuego's crater and drifted W and SW. Explosions during 17 and 19-21 May
generated ash plumes that rose 350-650 m and drifted 6 km W and SW. On 19
and 21 May explosions ejected incandescent material 100 m above the crater. GUATEMALA - Santa Maria - Santiaguito May 22nd, 2013 INSIVUMEH reported that on 16 May an explosion from Santa María's Santiaguito lava-dome complex produced an ash plume that rose 600 m and drifted 6 km SE. Ashfall was reported in La Florida and Monte Claro. A lava flow on the NE lava dome traveled S. During 20-21 May a few explosions generated ash plumes that rose 500-700 m and drifted 10 km W and SW. INSIVUMEH reported that on 23 April two explosions were accompanied by white plumes that rose 800 m above Santa María's Santiaguito lava-dome complex and drifted SW. The next day explosions produced ash plumes that rose 600 m and drifted SSW. Avalanches were generated by active lava flows on the SW flank. Explosions were heard on 25 April but cloud cover prevented visual confirmation. On 28 April a small explosion generated a white plume that rose 500 m and drifted NE. Explosions on 29 April produced ash plumes that rose 800 m and drifted SE, causing ashfall in San Jose, La Quina, and areas near Calahuache. INSIVUMEH reported that during 27-29 March explosions from Santa María's Santiaguito lava-dome complex produced ash plumes that rose 800 m and drifted SW. During 29-30 March ashfall was reported in El Faro (SW flank) and La Florida (5 km S). An explosion during 1-2 April generated ash plumes that rose 500 m and drifted SE, causing ashfall in San José. Avalanches were generated by active lava flows during 29 March-2 April. INSIVUMEH reported that during 13-19 March explosions from Santa María's Santiaguito lava-dome complex produced ash plumes that rose as high as 4 km and drifted NE, E, S, SW, and W. Explosions were heard during 25-26 March. Avalanches from lava-flow fronts traveled down the flanks, and incandescence in the crater was observed on some nights. Ashfall was reported in El Faro (SW flank) and La Florida (5 km S) during 13-14 and 25-26 March, in Quetzaltenango (18 km WNW) during 17-18 March, and in San Jose on 19 March. INSIVUMEH reported that during 13-19 March explosions from Santa María's Santiaguito lava-dome complex produced ash plumes that rose as high as 4 km and drifted NE, E, S, SW, and W. Avalanches from lava-flow fronts traveled down the flanks, and incandescence in the crater was observed on some nights. Ashfall was reported in El Faro (SW flank) and La Florida (5 km S) during 13-14 March, in Quetzaltenango (18 km WNW) during 17-18 March, and in San Jose on 19 March. (scientific blog about Santiaguito). 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 May 22nd, 2013 INSIVUMEH reported that weak incandescence from Pacaya's MacKenney cone was observed through the night during 15-16 May. Blue and white plumes rose 800 m and drifted S. On 17 May white plumes drifted W and NW. Incandescence from the crater was again observed at night during 19-21 May. On 20 and 21 May Strombolian activity ejected material 25 m above the crater. INSIVUMEH reported that on 23 April fumarolic plumes from Pacaya's MacKenney cone rose 100 m and drifted N. On 24 April tephra was ejected 25 m high by weak explosions. Incandescence from the crater was observed through the night, and explosions were detected the next day. Incandescence and explosions were again detected on 29 April. As of the 8th of April, INSIVUMEH team climbed the volcano and filmed the small active "lava lake" in the Mmackenney crater during their visit (video). INSIVUMEH reported that during 13-14 and 16-18 March weak gas-and-ash plumes rose from Pacaya and drifted N, NW, and S. A diffuse white plume rose less than 500 m and drifted E on 19 March. INSIVUMEH reported that during 8-12 March diffuse white plumes rose from Pacaya and drifted N, E, S, and SW. INSIVUMEH reported that on 5 March a gas-and-ash plume rose from Pacaya's MacKenney cone and drifted S. Based on INSIVUMEH notices, CONRED reported that explosions at Pacaya detected on 13 February were accompanied by rumbling. No material was ejected. The next day a diffuse white plume rose 200 m and drifted W and SW. Rumbling was heard in San Francisco de Sales (5 km N) and San Vicente Pacaya (5 km NW). 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. ************************************************************************************************************************* 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 ************************************************************************************************************ COSTA RICA- Poas Volcano October 28th, 2012 OVSICORI-UNA reported that on October 27, 2012 at 5:57 pm a phreatic eruption at Lake Poás ultra-acid of moderate energy was recorded by seismographs OVSICORI-A located at the top of the volcano. This eruption produced the ejection of agua, sulfur-rich sediments and rock fragments out of the lake. Hours earlier, at 11:20 am, there was a small phreatic eruption was also recorded by seismographs.
According to a news COSTA RICA - Turrialba volcano February 5th , 2012 OVSICORI-UNA reported that while conducting field work at Turrialba during 2-3 February, scientists observed incandescence with temperatures between 600-700 degrees Celsius from the three main vents of the W crater. The vents are comprised of the 2010 vent (on the SW rim), the 2011 vent (on the N side at the bottom of the crater), and the 2012 vent (on the SE flank). During the evening of 18 January 2012 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.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 February 28th, 2013 OVSICORI-UNA received reports at 0530 on 26 February 2013 of pulsing white
plumes rising from Rincon de la Vieja's active crater about every four
minutes. The seismic records showed no signals associated with a phreatic
eruption or sudden gas output. Cloud cover prevented views of the active
crater during an overflight later that day, however clear views of the N
and S flanks and areas SW showed no changes. NICARAGUA - Telica volcano September 20th, 2012 During 10-11 September INETER reported "jet" sounds from Telica, two
incandescent fumaroles, and gas-and-steam plumes rising 100-200 m above the
crater. On 11 September two small explosions occurred in the crater. During
12-14 and 17 September gas plumes rose 30-150 m and incandescence from the
crater was observed. Gas measurements on 14 and 17 September showed normal
levels of sulfur dioxide emissions. NICARAGUA - San Cristobal volcano January 2nd, 2013 INETER reported that on 26 December four explosions at San Cristóbal produced ash plumes that were observed in satellite imagery drifting W and reaching the Pacific Ocean. Ashfall was reported in areas within 5-6 km of the volcano. The next day explosions produced ash plumes that rose 200 m above the crater. On 28 December gas-and-ash plumes drifted NW, W, and SW, reaching the Pacific Ocean and the coast of El Salvador. Explosions were detected until 1100. Sulfur dioxide emissions continued and drifted W and SW; the emissions decreased the next day. As of the 25th of December, INETER reported that on 25 December at 1800 seismicity at San Cristóbal increased. A series of explosions starting at 2000 produced ash-and-gas plumes that rose 500 m above the crater and drifted SW and likely W. Ash fell near the volcano. Seismicity increased significantly the next day. Explosions continued to generate ash-and-gas plumes that rose 2.5 km above the crater and drifted N, W, and SW as far as the Pacific Ocean (30-40 km SW and W, respectively). Ashfall was reported in areas downwind, including Puerto Morazan, Jiquilillo, Aposentillo, Tonalá, El Viejo, Santa Marta, and the cities of Chinandega, Chichigalpa, Corinth, and Realejo. According to news articles, some families near the volcano self-evacuated.(video). Orange alert level has been decreated for the Chinandega area. PREVIOUS NEWS - On 10 September 2012 , INETER reported that seismicity decreased after the 8 September eruption at San Cristóbal. Sulfur dioxide emissions had decreased since the previous day. During 10-11 September steam plumes rose 200-300 m above the crater and drifted W. Three small explosions on 11 September generated ash-and-gas plumes that rose 300 m above the crater and drifted W. An explosion and ash venting was observed a few hours later; a plume drifted S and ash fell on the flanks. The seismic network detected small explosions on 13 September. Sulfur dioxide gas emissions were above normal, and similar to levels detected on 8 September. Sulfur dioxide gas emissions increased on 14 September. The next day a small explosion was observed and gas plumes drifted NE. Gas plumes drifted N on 17 September. INETER reported that on 8 September three explosions from San Cristóbal produced ash-and-gas plumes that rose 1.5 km above the crater and drifted 9 km/hr NW. Ashfall was reported in El Viejo (18 km WSW), El Chonco, and Ranchería. Sporadic explosions later that day generated ash plumes that rose 1.5-5 km and drifted 50 km WNW. Ash fell in an area covering 2,438 square kilometers, including the communities of El Viejo, La Grecia, La Joya, Santa Catalina, El Piloto, Las Banderas, Las Rojas, Carlos Fonseca, Jiquilillo, Mechapa, and Cosiguina. Ashfall was 5 cm thick in areas near the crater and up to 3 mm thick in more distant places. Sulfur dioxide emissions were 3,221 tons per day, well above the normal range of 550 to 700 tons per day. A resident near the volcano reported landslides and falling rocks in the N part of the crater. Incandescent rocks fell in areas NW, causing burns on livestock. Residents in Versalles Arriba, near the crater, reported seeing a fissure. According to a news article, officials evacuated about 3,000 people. SINAPRED reported that airplanes were diverted around San Cristóbal to other airways. (video). 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 planned for early December 2012- registration open here NICARAGUA - Apoyeque caldera September 12th, 2012 INETER reported that a seismic swarm near Apoyeque started at 1627 on 6 September in an area between the volcano and Managua (less than 10 km SW). At the time of the report, almost four hours after the start of the event, 17 earthquakes had been detected; three events were M 2.3-3.7, at depths ranging from 2.8 to 6 km. No earthquakes were recorded on 9 September. The Apoyeque volcanic complex occupies the broad Chiltepe Peninsula, which extends into south-central Lake Managua. The peninsula is part of the Chiltepe pyroclastic shield volcano, one of three large ignimbrite shields on the Nicaraguan volcanic front. A 2.8-km wide, 400-m-deep, lake-filled caldera whose floor lies near sea level truncates the low Apoyeque volcano, which rises only about 500 m above the lake shore. The caldera was the source of a thick mantle of dacitic pumice that blankets the surrounding area. The 2.5 x 3 km wide lake-filled Xiloá (Jiloá) maar, is located immediately SE of Apoyeque. The Talpetatl lava dome was constructed between Laguna Xiloá and Lake Managua. Pumiceous pyroclastic flows from Laguna Xiloá were erupted about 6100 years ago and overlie deposits of comparable age from the Masaya plinian eruption. (GVN/GVP) *************************************************************************************************************************** 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 *********************************************************************************************************************** COLOMBIA - Galeras volcano April 22nd, 2013 INGEOMINAS reported that during 15-21 May seismicity at Galeras was at a low level; during 19-20 May earthquakes with magnitudes 2.6 or less were concentrated in an area 3 km SW at depths near 4 km. Gas plumes rose 500 m above the crater and contained small amounts of ash during 15-16 and 20-21 May. Sulfur dioxide emissions were low. The Alert Level remained at III (Yellow; "changes in the behavior of volcanic activity"). INGEOMINAS reported that during 10-16 April 2913 earthquakes at Galeras were located in various areas as far as 13 km from the crater, at depths no greater than 14 km and with maximum magnitudes of 2. Moderate levels of sulfur dioxide were detected; plumes drifted NW. Cameras recorded ash emissions all week, especially on 9, 11, 12, and 14 April, when pulsating activity produced plumes that drifted W. Plumes rose no more than 1 km above the crater. The Alert Level remained at III (Yellow; "changes in the behavior of volcanic activity").INGEOMINAS reported that during 30 October-6 November 2012 seismicity at Galeras fluctuated but was slightly lower compared to the previous week. Sulfur dioxide gas emissions were low. Cameras around Galeras recorded gas-and-ash plumes rising from the crater on 30 October and 1 November. The Alert Level remained at III (Yellow; "changes in the behavior of volcanic activity"). 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 Ruiz April 18th, 2013 INGEOMINAS reported that during 13-14 April seismicity associated with
fluid movement beneath Nevado del Ruiz was detected along with
volcano-tectonic earthquakes. The earthquakes were located NW of Arenas ************************************************************************************************************************* PERU - Sabancaya volcano April 12th, 2013 On 10 May Instituto Geofísico de Perú (IGP) reported that results of an
interferogram of Sabancaya provided by a collaborator at Cornell University
showed that an area of deformation (subsidence of 7 cm centered at 6 km NE
of the crater) was coincident with the main area of seismicity.
Volcano-tectonic (VT) earthquakes continued to dominate the seismic
signals, although long-period (LP) events continued to be detected. There CHILE - ARGENTINA - Copahue volcano May 10th, 2013 OVDAS-SERNAGEOMIN reported that an explosion from Copahue at 1015 on 7 May recorded by a webcam produced a gas, steam, and ash plume that rose 350 m and drifted SE. Incandescence from the crater was visible at night. The Alert Level was raised to Yellow. Based on analysis of satellite imagery and a pilot observation, the Buenos Aires VAAC reported that on 28 March steam-and-gas emissions with small amounts of ash rose from Copahue. Previously, OVDAS-SERNAGEOMIN reported that during 29 January-4 February the web camera near Copahue recorded white gas plumes rising 350-1,550 m above the crater and drifting E and SE. Seismicity fluctuated but mostly remained at low levels. The Alert Level was lowered to Yellow on 4 February. The Buenos Aires VAAC noted that although a pilot reported an ash plume between the altitudes of 3-4.6 km (10,000-15,000 ft) a.s.l. on 4 February, no ash was detected in mostly clear satellite images. The VAAC also noted that steam emissions with possible ash were recorded by the OVDAS webcam. OVDAS-SERNAGEOMIN reported that during 22-28 January the web camera near Copahue recorded white gas plumes rising 100-800 m above the crater and drifting E and SE. Seismicity remained at low levels. An explosion at 2355 on 22 January produced a gas plume (with no ash) that rose 1.45 km above the crater. The Alert Level remained at Orange.OVDAS-SERNAGEOMIN reported that the web camera near Copahue recorded white gas plumes rising 250-1,300 m above the crater during 15-18 January and drifting W and NW. Seismicity remained at low levels. The Alert Level was lowered from Orange to Yellow on 18 January. A seismic swarm of long-period earthquakes started at 1420 on 22 January. The earthquakes were initially deep but became shallower, and volcano-tectonic events were more frequently detected, until the next report posted at 2200. Web camera and satellite images did not show any changes. The Alert Level was raised to Orange. OVDAS-SERNAGEOMIN reported that the web camera near Copahue recorded white gas plumes rising 0.9-1.5 km above the crater during 9-15 January and drifting NNE, E, ESE, and SSE. Incandescence from the crater was observed on some nights. Satellite images showed plumes drifting 10 km E and SSE during 10-12 January. The Alert Level remained at Orange. OVDAS-SERNAGEOMIN reported that seismicity at Copahue during 31 December, and 2 and 4-5 January indicated magma movement focused at 4 km below the crater and moving to shallower depths. On 5 January seismicity increased as well as gray emissions observed with a web camera. The Alert Level was raised to Orange. Incandescence on the crater was noted during 5-6 January, and plumes rose 200 m above the crater and drifted E during 5-7 January. OVDAS-SERNAGEOMIN reported that during 25-29 December white plumes observed with a web camera installed near Copahue rose 450-850 m and drifted NE and E. Plumes detected in satellite imagery drifting 16 km NE on 26 December. Incandescence from the crater was observed at night during 26-28 December; explosions were detected during 27-28 December. Seismicity had decreased during the reporting period. The Alert Level was lowered to Yellow on 29 December. As of the 25th of December, SERNAGEOMIN reported that the activity decreased to low values and tremor was not detected. Cloud cover obscured web camera views. Diffuse plumes visible in satellite images drifted 70 km SE. On 24 December seismicity decreased. The camera recorded crater incandescence which increased to heights of 200 m with explosions. Incandescent blocks were again ejected with Strombolian explosions. Plumes rose 300 m and drifted SE; they were mostly white, but turned dark with ash during explosions. The Alert Level was lowered to Orange. On 23 December incandescence from the crater increased with explosions, as high as 450 m. Strombolian activity ejected incandescent blocks, and mostly white plumes turned dark during explosions. The plumesrose 1 km and drifted SE. As of the 23rd of December in the morning , SERNAGEOMIN reported that an eruptive activity started on Saturday 22nd of December at 10:45 am (local time) at the Copahue volcano. An explosive activity started and a volcanic plume rose at about 1500 m high and drifted 300 km toward the Southeast according to MODIS satellite image taken at 2:45 pm (TU). Following this phreatic phase, magmatic activity started and local scientific authorities decreted alert level orrange then Red. No evacuation was planned for the moment. Scientists aboard an overflight observed a low plume rising 1.5 km above a vent in Del Agrio Crater, in the same area as the previous eruption in 2000, and drifting SE. The scientists noted that at 1600 the emissions changed from ash to gas. Later that day web cameras showed incandescence from the crater reflecting in the clouds. The Alert Level was raised to Red, and people within a 15-km-radius and along drainages were warned about potential increases in activity or lahars. Volcán Copahue is an elongated composite cone constructed along the Chile-Argentina border within the 6.5 x 8.5 km wide Trapa-Trapa caldera that formed between 0.6 and 0.4 million years ago near the NW margin of the 20 x 15 km Pliocene Caviahue (Del Agrio) caldera. The eastern summit crater, part of a 2-km-long, ENE-WSW line of nine craters, contains a briny, acidic 300-m-wide crater lake (also referred to as El Agrio or Del Agrio) and displays intense fumarolic activity. Acidic hot springs occur below the eastern outlet of the crater lake, contributing to the acidity of the Río Agrio, and another geothermal zone is located within Caviahue caldera about 7 km NE of the summit. Infrequent mild-to-moderate explosive eruptions have been recorded at Copahue since the 18th century. Twentieth-century eruptions from the crater lake have ejected pyroclastic rocks and chilled liquid sulfur fragments. The previous eruption in June 2011 of Chile's Puyehue volcano interfered with air travel in much of the southern cone of South America and as far away as Australia. (GVN/GVP) CHILE - Laguna del Maule volcano - Descabezado Grande volcano March 9th, 2013 As of the 8th of March, following important changes of the geophysical parameters, SERNAGEOMIN and ONEMI raised to the alert level to yellow for this volcanic field.
OVDAS-SERNAGEOMIN reported that during 1-28 February seismicity increased
at Descabezado Grande, in the Laguna del Maule volcanic complex area. There
were 127 earthquakes detected, with magnitudes 1.7 or less, mostly
comprised of volcano-tectonic earthquakes. The seismic swarms were
associated with deformation and considered to beat a high level. CHILE - Lascar volcano April 6th, 2013 OVDAS-SERNAGEOMIN reported that during March a web camera monitoring Láscar
recorded white gas plumes rising 600 m above the crater. At night during
2-4 April incandescence from the crater was observed. On 3 April increased
emissions from the crater fluctuated from white to gray, indicating
possible ash. Plumes rose 320 m and drifted SE. Seismicity remained at
normal levels during the increased emissions. On 5 April the Alert Level
was raised to Yellow.
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) |
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JAPAN - Suwanose-Jima volcano (Ryukyu Islands) March 8th, 2012 JAPAN - Sakurajima volcano May 22nd, 2013 JMA reported that during 13-17 May Sakura-jima's Showa Crater had 13
explosions ejecting tephra that fell at most 1.8 km from the crater. Crater
incandescence was occasionally detected at night. Based on information from
JMA, the Tokyo VAAC reported that during 15, 17-18, and 20-21 May
explosions produced plumes that rose to altitudes of 1.2-3.7 km
(4,000-12,000 ft) a.s.l. and drifted E and W. On 21 May a pilot observed an *********************************************************************************************************************** |
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USA - Kilauea volcano ( Hawaian islands) May 22nd, 2013 During 15-21 May HVO reported that the circulating lava lake occasionally rose and fell in the deep pit within Kilauea's Halema'uma'u Crater. The plume from the vent continued to deposit variable amounts of ash, spatter, and Pele's hair onto nearby areas. At Pu'u 'O'o Crater, glow emanated from three spatter cones and a small lava pond on the E part of the crater floor. Lava from base of Pu'u 'O'o cone traveled N and was named the Kahauale'a II flow. Peace Day activity, fed by lava tubes extending from Pu'u 'O'o, consisted of lava flows active on the coastal plain that were entering the ocean at a location outside the National Park boundary. As of the 17th of may, HVO reported that at the summit, tiltmeters recorded slowing DI deflationary tilt and the lava lake level continued to drop but at a slower rate. At Pu`u `O`o vent in the middle east rift zone, there was no new activity within the crater but lava flows remained active on the north base of the cone. To the southeast, the Peace Day pali flow remained active on the coastal plain while the main flow branch continued to enter the ocean in at least 2 locations spanning the Hawai`i Volcanoes National Park boundary. Gas emissions remained elevated. During 8-14 May HVO reported that the circulating lava lake occasionally rose and fell in the deep pit within Kilauea's Halema'uma'u Crater. The plume from the vent continued to deposit variable amounts of ash, spatter, and Pele's hair onto nearby areas. At Pu'u 'O'o Crater, glow emanated from three spatter cones and a small lava pond on the E part of the crater floor. Lava from the E lava pond traveled down the N, NE, E, and S flanks, extending beyond the base of Pu'u 'O'o cone. During 10-11 May the SW spatter cone erupted lava, and during 11-12 May the SE spatter cone also produced flows. Peace Day activity, fed by lava tubes extending from Pu'u 'O'o, consisted of lava flows active on the pali and on the coastal plain. Lava also entered the ocean in at least two locations spanning the National Park boundary. As of the 10th of May, HVO reported that conditions of unrest have increased slightly: At the summit, there was general inflation with a rising lava lake, clusters of earthquakes south of Halema`uma`u and spread out across the south flank, and an increase in microseismicity in the upper east rift zone. At Pu`u `O`o vent in the middle east rift zone, inflation continued and lava flows advanced down the flank of the cone to the northeast and north approximately along the track of the now-dead Kahauale`a flow. The Peace Day pali flow progressed across the coastal plain while the main flow branch continued to enter the ocean in at least 2 locations spanning the Hawai`i Volcanoes National Park boundary. Gas emissions remained elevated. During 1-7 May HVO reported that the circulating lava lake occasionally rose and fell in the deep pit within Kilauea's Halema'uma'u Crater. The plume from the vent continued to deposit variable amounts of ash, spatter, and Pele's hair onto nearby areas. At Pu'u 'O'o Crater, glow emanated from three spatter cones and a small lava pond on the E part of the crater floor. Small lava flows issued from the N spatter cone on 1 May and from the SW cone on 2 May. The lava pond overflowed during 3-4 and 6-7 May. Peace Day activity, fed by lava tubes extending from Pu'u 'O'o, consisted of lava flows active above the pali SE of Pu'u 'O'o, on the pali, and on the coastal plain. Lava also entered the ocean in at least two locations spanning the National Park boundary. On 3 May a breakout on the top of the pali produced a lava flow that traveled down to the coastal plain in about 1 hour. Branches from the flow advanced during 4-6 May. As of the 3rd of May, HVO reported that no significant changes: at the summit, the lava lake remained steady. At Pu`u `O`o vent in the middle east rift zone, the usual sources glowed overnight within the crater with a minor lava flow issuing from the southwest spatter cone in the early afternoon yesterday and a brief east pond overflow early this morning; to the southeast, the Peace Day flow entered the ocean at several locations that produced two gas plumes spanning the Hawai`i Volcanoes National Park boundary. Gas emissions remained elevated. During 24-30 April HVO reported that the circulating lava lake periodically rose and fell in the deep pit within Kilauea's Halema'uma'u Crater. The plume from the vent continued to deposit variable amounts of ash, spatter, and Pele's hair onto nearby areas. At Pu'u 'O'o Crater, glow emanated from three spatter cones, a small lava pond on the crater floor, and cracks in a recently emplaced lava flow on the crater floor. Small lava flows issued from the SW spatter cone on 24 April. On 28 April lava gushed from the N spatter cone for more than 2.5 hours, covering the N portion of the crater floor. A second flow was observed on 29 April. Peace Day activity, fed by lava tubes extending from Pu'u 'O'o, consisted of lava flows active above the pali SE of Pu'u 'O'o, on the pali, and on the coastal plain. Lava also entered the ocean at two or three locations spanning the National Park boundary. During 17-23 April HVO reported that the circulating lava lake periodically rose and fell in the deep pit within Kilauea's Halema'uma'u Crater. The plume from the vent continued to deposit variable amounts of ash, spatter, and Pele's hair onto nearby areas. At Pu'u 'O'o Crater, glow emanated from three spatter cones and a small lava pond on the crater floor. Just before midnight on 19 April a vigorous lava flow gushed out of the N spatter cone and quickly covered the N portion of the crater floor, then went over the E rim. The lava pond on the NE crater's edge. briefly overflowed. On 21 April the two spatter cones on the S portion of the crater floor produced lava flows. Two lava flows (Peace Day and Kahauale'a) were fed by lava tubes extending from Pu'u 'O'o. Multiple lava flows from the NE spatter cone, collectively called the Kahauale'a flow, stopped advancing on 20 April, although a few breakout lava flows were observed during 20-22 April. Peace Day activity consisted of lava flows active above the pali (5 km SE of Pu'u 'O'o), on the pali, and on the coastal plain. Lava also entered the ocean at two or three locations spanning the National Park boundary..As of the 19th of April, HVO reported that there were no significant changes. DI inflation and a rising, circulating lava lake were the action at the summit of Kilauea volcano while the Pu`u `O`o vent in the middle east rift zone fed two lava flows: the Kahauale`a lava flow, which was weakly active about 5 km to the northeast on older Pu`u `O`o flows, and the Peace Day flow, which extended more than 10 km to the southeast and was entering the ocean in two main locations spanning the National Park boundary. Gas emissions remained elevated. During 10-16 April HVO reported that the circulating lava lake periodically rose and fell in the deep pit within Kilauea's Halema'uma'u Crater. The plume from the vent continued to deposit variable amounts of ash, spatter, and Pele's hair onto nearby areas. January 2013 marked the 30 th anniversary of Kilauea's East Rift Zone eruption, which began on January 3, 1983, and continues today. 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 ************************************************************************************************************************* U.S.A. - Mauna Loa ( Hawaii) January 12th, 2013 No recent news about Mauna Loa since 2010 - News 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. ************************************************************************************************************************** USA - Cleveland volcano (Alaska) May 22nd, 2013 AVO reported that during 14-15 and 18-19 May elevated surface temperatures over Cleveland were observed in satellite images. Clouds obscured views during 16 and 20-21 May. Satellite image analysis revealed that a small lava flow had breached the SE rim of the summit crater and traveled as far as1.5 km down the flank. The Volcanic Alert Level remained at Watch and the Aviation Color Code remained at Orange. Cleveland Volcano remained active during the past week 10-17 May. During clear satellite views, vigorous steam plumes and elevated surface temperatures were observed. Re-analysis of earlier images revealed that a small lava flow had breached the southeast rim of the summit crater and extended up to about 1.5 km down the flank.AVO reported that during 8-9 May no further explosions had been detected at Cleveland based on regional infrasonic data. Cloud cover prevented satellite observations of the crater. Clear satellite views revealed vigorous steam plumes during 10-11 May and thermal anomalies during 10-14 May. On 14 May AVO noted that analysis of recent satellite imagery revealed a 100-m-wide lava flow, breaching the SE rim of the summit crater, and extending about 1.5 km down the SE flank. The Volcanic Alert Level remained at Watch and the Aviation Color Code remained at Orange. As of the 6th of may, AVO reported that low-level eruption at Cleveland volcano continues. Explosions were detected at 11:23 PM AKDT 5 May (7:23 UTC 6 May) and 08:00 AM AKDT 6 May (16:00 UTC) by the Okmok network, 120 km (80 mi) to the northeast. Overall however infrasonic data suggest that the eruption may have waned since yesterday. The volcano is obscured by clouds in satellite data, but a thermal anomaly continues to be visible. As of the 4th of may, AVO reported that the current eruption of Cleveland Volcano, which began with an explosion on the morning at 5:00 AM AKDT (13:00 UTC), has transitioned into a continuous low-level eruption. The activity is characterized by long duration airwave signals measured on the nearby Okmok seismic network, 120 km (80 mi) to the northeast. Larger discrete explosions occurred at roughly 5:00 AM, 9:17 AM, and 11:44 AM AKDT (13:00, 17:17, and 1944 UTC). Satellite and webcam data suggest continuous low-level emissions of gas, steam, and minor amounts of ash over the past several hours with a faint plume extending eastward below 15,000 ft. Satellite data also show highly elevated surface temperatures at the summit. AVO reported that during 6-7 March clouds obscured satellite views of Cleveland's lava dome. On 8 March AVO noted that the lava dome had remained unchanged since 6 February, and the last thermal anomalies were observed on 26 February. Although cloud cover often prevents observations of the dome, clear views between 1 and 5 March verified no changes. The Volcanic Alert Level was lowered to Advisory and the Aviation Color Code was lowered to Yellow. AVO reported that during 27 February-5 March clouds obscured satellite views of Cleveland's lava dome. The Volcanic Alert Level remained at Watch and the Aviation Color Code remained at Orange. AVO reported that during 20-26 February clouds obscured satellite views of Cleveland's lava dome. The Volcanic Alert Level remained at Watch and the Aviation Color Code remained at Orange. AVO reported that during 12-15 February elevated surface temperatures from Cleveland's lava dome were detected in satellite images. Clouds obscured views of the dome during 16-19 February. The Volcanic Alert Level remained at Watch and the Aviation Color Code remained at Orange. On 6 February AVO reported that satellite imagery acquired on 30 January indicated that a lava dome had grown in Cleveland's summit crater, prompting AVO to raise the Volcanic Alert Level to Watch and the Aviation Color Code to Orange. The dome was about 100 m in diameter and may have begun forming as early as 24 January when elevated surface temperatures were observed in satellite images. The size and shape of the dome appeared to be unchanged based on satellite data acquired on 2 February. Elevated surface temperatures from the lava dome were detected during 5-6 and 8-11 February. 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. ************************************************************************************************************************ USA - Iliamna volcano (Alaska) January 10th, 2013 On 9 January, AVO reported that unrest at Iliamna had decreased over the past several months, reaching background levels. The Volcano Alert Level was lowered to Normal and the Aviation Color Code was lowered to Green. The report also noted that occasional small earthquakes had continued, but at a greatly reduced rate and magnitude relative to the peak of unrest in March 2012. Steam and sulfur gas emissions continued to be observed from sites near the summit during periods of favorable meteorological conditions, not unusual at Iliamna. Previously,AVO reported that during 24-30 October 2012 seismicity at Iliamna remained slightly elevated. Clear satellite and web camera views showed nothing unusual. The Alert Level remained at Advisory and the Aviation Color Code remained at Yellow. As of the 15th of June, AVO reported that seismic activity at Iliamna Volcano continue slightly above background, and nothing unusual has been observed in satellite or web camera images during clear periods. Seismic activity at Iliamna Volcano has been slightly above background throughout the past week. Nothing unusual was observed in mostly clear web camera and satellite images during the week from 12th to 18th of May. AVO has received no reports of unusual activity at the volcano.Seismic activity at Iliamna Volcano remains slightly above background, and the rate of seismic activity has declined over recent weeks. Nothing unusual was observed in web camera and cloudy satellite images over the past 24 hours. As of the 6th of April seismic activity at Iliamna Volcano remains slightly above background. Intermittent clear web camera and satellite views over the past week show no unusual activity.The current activity at Iliamna does not indicate an imminent or certain eruption. A similar seismic swarm at Iliamna in 1996-1997 was not followed by eruptive activity. Iliamna is a prominent, 3053-m-high glacier-covered stratovolcano in Lake Clark National Park on the western side of Cook Inlet, about 225 km SW of Anchorage. Its flat-topped summit is flanked on the south, along a 5-km-long ridge, by the prominent North and South Twin Peaks, satellitic lava dome complexes. The Johnson Glacier dome complex lies on the NE flank. Steep headwalls on the southern and eastern flanks expose an inaccessible cross-section of the volcano. Major glaciers radiate from the summit, and valleys below the summit contain debris-avalanche and lahar deposits. Only a few major Holocene explosive eruptions have occurred from the deeply dissected volcano, which lacks a distinct crater. Most of the reports of historical eruptions may represent plumes from vigorous fumaroles east and SE of the summit, which are often mistaken for eruption columns (Miller et al., 1998). Eruptions producing pyroclastic flows have been dated at as recent as about 300 and 140 years ago (into the historical period), and elevated seismicity accompanying dike emplacement beneath the volcano was recorded in 1996. U.S.A. - Pavlof volcano (Aleutian Islands) May 24th, 2013
The eruption of Pavlof continues at low levels today. Small discrete events, likely indicative of small explosions continue to be detected on seismic and pressure sensor networks over the past 24 hours. Seismic tremor declined markedly on Tuesday morning and has not resumed. Cloudy conditions obscured satellite observations of the volcano over the past 24 hours but a pilot report and photos from yesterday afternoon showed a very weak steam and gas plume with little to no ash issuing from the vent. Elevated surface temperatures were observed in satellite images, even through cloud cover, indicative of continued activity. During 18-19 May a narrow plume of steam, ash, and gas, occasionally rising
up to 6.7 km (22,000 ft) a.s.l., and drifting southeast, was visible in
satellite images. Pilot reports indicated that lava fountaining and ash
emission continued. Overnight, trace amounts of ash fell on the community
of Sand Point. During the afternoon on 19 May pilots reported that ash
plumes rose to altitudes of 4.6-6.7 km (15,000-22,000 ft) a.s.l. Trace
amounts of ash fell in Nelson Lagoon, 78 km NNE, during 19-20 May. The
Volcanic Alert Level remained at Watch and the Aviation Color Code remained
at Orange.
A news article stated that on 20 May a regional airline canceled about a
dozen flights to several remote communities, including Sand Point. Another |
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ITALY - Etna volcano ( Sicily) April 28th, 2013 The 13th episode of lava fountaining (paroxysm) of this year at Etna's New Southeast Crater took place on the evening of 27 April 2013, one week after the previous episode, and after a "prelude" characterized by Strombolian activity and frequent ash emissions. which had started already on 21 April, just one day after the 20 April paroxysm. After a gradual increase in both the eruptive activity and in the volcanic tremor amplitude, which had started on the evening of 26 April, the paroxysmal phase began shortly after sunset on 27 April, with lava fountains 300-500 m high, emission of lava flows from the southeastern and northeastern flanks of the New Southeast Crater cone and from the "saddle" between the two Southeast Crater cones, forming small lava flows toward south and north. A portion of the eastern flank of the cone collapsed, generating a pyroclastic flow, which advanced about 1 km toward the Valle del Bove. Furthermore, a cloud of gas and pyroclastic material formed, which was blown by the wind to the northeast, resulting in ash and lapilli falls in the area of Linguaglossa, and more distant Taormina and Messina. The paroxysmal phase lasted about 2 hours; lava emission toward southeast continued for many hours and ceased during the forenoon of 28 April. Since the last paroxysm, eruptive activity continued with strombolian explosions. but the volcanic tremor decreased during the past days. INGV reported that a new episode of lava fountaining (paroxysm) has taken place on the afternoon of 20 April 2013 at Etna's New Southeast Crater (NSEC), the 12th event of this type within two months. Explosive activity had resumed on 19 April, less than 24 hours after the end of the previous paroxysm. During the night of 19-20 April, the explosive activity switched to quiet, non-explosive emission of lava from the eruptive fissure at the southeastern base of the NSEC cone, which had opened a the end of the 12 April paroxysm but remained inactive during the subsequent paroxysm on 18 April. During the day of 20 April, effusive activity continued, but explosive phenomena were virtually absent until about 15:00 GMT (=local time -2), when violent explosions started, which rapidly passed into a lava fountain accompanied by the formation of an eruption column. The lava fountains reached heights of 800-1000 m above the crater, whereas the cloud of pyroclastic material expanded toward east-southeast, leading to heavy falls of ash and lapilli over the areas of Zafferana Etnea, Milo, Santa Venerina and further downslope, in the area of Giarre. A well-fed lava flow expanded down the western slope of the Valle del Bove, locally interacting with residual patches of snow, which resulted in the formation of lahars and ground-hugging steam and ash clouds, a phenomenon seen several times during previous paroxysms during the winter season on Etna. Lava fountaining continued for about one hour, and then passed into sporadic explosions and ash emission between 16:15 and 16:25. The episode was essentially over by 16:40, although the lava flow is still showing movement and possibly is still being fed from its source vent (19:00 GMT on 20 April 2013). The 11th paroxysmal eruptive episode of the year 2013 at Etna's New Southeast Crater occurred on the early afternoon of the 18th of April, with lava fountains, a lava flow directed into the Valle del Bove, and a column of ash and lapilli that expanded south-southwestward. The phase of lava fountaining was followed by a long series of powerful explosions, with detonations audible as far as Catania; this activity essentially ceased in the late afternoon. On the evening of 16 April 2013, mild explosive activity resumed at Etna's New Southeast Crater, with ash emissions and small Strombolian explosions. This activity continued, with minor fluctuations until the early morning of 18 April, when the intensity and frequency of the explosions started to increase. At (07:30 GMT [=local time -2] on 18 April), Strombolian activity was nearly continuous, and the volcanic tremor amplitude was showing a gradual increase. According to preliminary news from INGV, a new eruptive episode (paroxysm) - the 10th of the year 2013 - occurred during the late forenoon of 12 April 2013 at Etna's New Southeast Crater, with lava fountains and a tall eruption column heavily charged with pyroclastics (ash and scoriaceous lapilli). Lava flows were emitted from the "saddle" area between the two Southeast Crater cone, toward south and then southeast, from the New Southeast Crater itself toward southeast, and from vents on the northeast side of the cone. Eruptive activity started on the afternoon of 8 April with L'attività è iniziata nel pomeriggio del 8 aprile 2013, with explosions that emitted ash; this activity continued until the afternoon of 10 April, and then passed into Strombolian explosions. On 11 April, this activity gradually incrased, and became almost continuous on the evening, with powerful explosions and loud detonations. A more detailed report will be posted here shortly . .After 18 days of quiescence, Etna's New Southeast Crater produced the 9th eruptive episode (paroxysm) of this year on the afternoon of 3 April 2013, with lava fountains and powerful explosions, emission of lava flows from its southern, southeastern and northeastern flanks, and generation of a tephra cloud, which once more was blown southeast by the wind, toward the population centers of Zafferana Etnea, Santa Venerina, and Acireale. The "prelude" to this episode started on the morning of 2 April with small ash emissions, and Strombolian activity during the following night. Following the day before strombolian explosions, on the morning of March 16, the activity was still in progress, characterized by continuous explosions ejectecting incandescent material to a few tens of meters above the crater. The intensity of the explosive activity, increased between 6:15 PM and 6:30 PM, the time interval in which the strombolian explosions evolved in lava fountains and a slow overflow began to went down the eastern flank of the cone. Between 6:30 PM and 6:45 PM lava fountaining has quickly reached its maximum intensity, with sustained lava fountains that rose during few moments to one kilometer height. That was the beginning of the eighth eruptive paroxysm at 8:13 PM, at the Southeast Crater. During this phase a dense column of sustained pyroclastic material has been transported by winds towards the southeastern side of the volcano.The activity was maintained constant for about 20 minutes. At around 7:05 PM (UTC +2) gradual decrease occurred in the intensity of the fountains and lava ceased at around 7:15 PM. Between 7:15 PM and 7:45 PM ??some bursts of large bubbles of gas launched volcanic bombs incandescent of metric dimensions in all directions. The final explosive activity ceased shortly before 8:00 PM. The slow mobilization of pyroclastic material deposited on the steep southern flank of the east cone of the SEC, generated a slow avalanche that went down to the base of the same cone. At 04:50 on 17 March, there has been a strong explosive sequence lasted only a few minutes. The main explosion has produced a plume of gas and ash that rose vertically on top of the volcano for several hundred meters and drifted by the winds to the east. There were no replicas phenomenon. This morning at the base of the South East ESA was visible a fumarole, at the eruptive fissure opened on 28 February ( FEBC ) which only produced gas emissions. At 01:50 AM, on March 18 there was no eruptive activity. Previously, as of the 16th of March Etnawalk reported that during the afternoon yesterday, March 15, the strombolian activity has resumed from the eastern Southeast Crater cone. Activity has gradually intensified over the course of hours, but bad weather prevented complete observation of phenomena. However, few before dawn, it was possible to see that the explosions were continuous and throwing incandescent material several hundred feet over the edge of the crater. Strong explosions have been reported at the foothills of the volcano. Day real-time signals of INGV observed, yesterday afternoon, a slow and gradual increase of the average of the volcanic tremor. As of the 6th of March, INGV reported that a new paroxysmal episode occured yesterday evening. The eruptive phase started around 7:55 PM (local time) with a strombolian activity from the saddle between the two Southeast cones and slighlthy increasing during the next hours still accompanied with the Voragine strombolian explosions. At about 11 PM, a new lava flow issuing from the same eruptive zone and went down toward the South. In the early morning, at about 0:20 AM the paroxysmal phase started from the new Southeast cone with an intense lava fountaining. Around 0:34 AM a second lava flow was emitted from the East base of the new Southeast cone (from the notch) and went down to the Valle del Bove. This short paroxysm ended at about 1:15 AM and both lava foutaining and lava emission stopped. As of the 1st of March, INGV reported that following the yesterday paroxysm, lava flows were still active on the morning. Activity at the Voragine was also continuing with explosive ejection of incandescent material. On the late forenoon of 28 February 2013, Etna's New Southeast Crater has produced yet another paroxysmal eruptive episode, which culminated with the opening of an eruptive fissure in the saddle between the old and new cones of the Southeast Crater. A lava flow emitted from this fissure reached the monitoring station of Belvedere and descended onto the western slope of the Valle del Bove. Pyroclastic material and gas formed a large plume, which was blown eastward, leading to heavy fallout of ash and scoriae in the area between Milo and Fornazzo on Etna's flank, and Giarre and Riposto on the Ionian coast. This paroxysm had been preceded during the night of 27-28 February by intense Strombolian activity both at the Voragine and at the Bocca Nuova. On the morning of 27 February 2013, an episode of strong Strombolian activity and small lava fountains started within Etna's Bocca Nuova. This event is very similar to the episodes observed at the same crater between mid-January and early February; however, explosive activity was also observed at the Voragine, which since 1999 had not produced any magmatic activity. As of the 25th of February, INGV reported that following the paroxyms eruptive activity was continuing this morning. A lava flow is still went down from above part of the eruptive fissure opened at the base of the new Southeast cone. On the evening of 23 February 2013, a new episode of lava fountaining occurred again at Etna's New Southeast Crater, two-and-a-half days after the previous episode from the same crater, and 36 hours after the latest eruptive episode in the summit area, which took place at the Bocca Nuova on the morning of 22 February. The 23 Febriary paroxysm was more intense than its predecessors, with lava fountains up to 600-800 m tall, and an eruption cloud charged with ash and scoriae that was blown northeastward by strong wind, whereas the lava volume this time is smaller than that of the previous episodes. The culminating phase of this episode lasted less than one hour. As of the 21st of February, INGV reported that the fourth episode of lava fountaining at Etna's New Southeast Crater in little more than 48 hours took place on the morning of 21 February 2013. The new paroxysm occurred at 2:45 AM; this new activity started with a lava flow from a fissure located at the East base of the new Southeast cone. Then strombolian activity started at 4:40 AM. From 5:52 AM , the eruptive activity increased and an important overflowing occurred from the new Southeast cone generating a large lava flow toward the Valle Del Bove It's the fourth eruptive episode. Following the paroxysm during the early morning, a new increasing activity started the same day 20th of february at 11:56 AM characterized by ash venting from the new southeast cone. Around 2:07 PM the eruptive plume rose permanently from the cone. The rapid succession of three paroxysmal eruptive episodes in less than 36 hours is quite notable; the only known historic precedent of three paroxysms occurring in such a short time interval at Etna was the series of eruptive episodes in 2000. At that time, especially during the first few weeks of that series, in February 2000, paroxysmal episodes would occur sometimes at a rate of up to three per day. As of the 20th of February, INGV reported that in the early morning hours of 20 February 2013; southeast Crater has produced the second episode of lava fountaining within less than 24 hours, emitting an ash plume toward southeast, lava flows from the fissure cutting the southeastern crater rim and also from a new eruptive fissure, which opened on the lower southwestern flank of the cone, and small lahars. The last time that Etna produced two paroxysms in less than 24 hours was on 1 June 2000. Yesterday, during the early morning hours of 19 February 2013, Etna's New Southeast Crater produced a first lava fountaining episode, the first event of this kind since the paroxysm on 24 April 2012. During the preceding days, the same crater had been the site of intermittent, weak Strombolian activity. Following the increasing of the strombolian explosions, lava fountaining started around 4:40 AM and culminated to about 5:30 AM. A lava flow emission started around 4:45 AM and went down slowly toward the Valle Del Bove, reaching 2600 m elevation (North Sierra Giannicola Picola) around 6:30 AM. Previously, volcanologists visited Etna on 5 February and observed the recent changes that had taken place at Bocca Nuova Crater, notably the growth of a pyroclastic cone surrounding the eruptive vent in the SE portion of the crater. This cone had grown at least 50-70 m, about halfway up the inner crater wall, and was leaning into the wall. The entire crater floor was covered with recent lava. Later in the evening of 5 February a webcam recorded weak Strombolian activity at NSEC, which continued until daybreak the next day, and then became invisible due to deteriorating weather conditions. Seismic data showed an instantaneous increase of tremor at 1020; volcanic tremor amplitude rose to a peak within a few minutes after the start of the activity, and began to descend after less than one hour. People in the ski area on the NE flank of the volcano briefly saw a dense but ash-free gas plume rising from the summit. After the episode on 6 February through most of 8 February sporadic ash emissions from NSEC were observed, although poor weather conditions often prevented observations. On the evening of 8 February weak glow from NSEC was intermittently visible. At 2100 a webcam recorded fluctuating glow from within Bocca Nuova which became more intense over the next 10 minutes. Around 2125 jets of incandescent lava were repeatedly seen rising above a thick blanket of clouds drifting over the summit area of Etna. Contemporaneously, the volcanic tremor amplitude rose sharply. After 2200 the volcanic tremor amplitude began to decrease, whereas the eruptive activity continued without showing signs of diminishing until about 30 minutes later. After 2230 on 8 February and during 9-10 cloud cover prevented observations. A brief ash emission was observed on 10 February. As of the 2nd of February, INGV reported that a new explosive activity occurred at 2:59 AM on the early morning characterized by strombolian explosions from the summit of the new Southeast cone. Few hours later at 4:30 AM strombolian activity started from the Bocca Nuova crater. Following the beginning of the activity from the Bocca Nuova, explosions from the new Southeast cone decreased and stopped at about 5:50 AM. Strombolian activity continued from the Bocca Nuova and slighly dropped in the morning. As of the 31st of January, INGV reported that following an increasing of the tremor, strombolian explosions started from Bocca Nuova during the night 30th to 31st of January. Some explosions ejected blocs and incandescent volcanic bombs that rose to about many tens meters above the crater rim and were falling on the South part of the Bocca Nuova. As of the 29 th of January, INGV reported that the activity at the Bocca Nuova stopped at about 11 PM. As of the 28th of January INGV reported that activty slightly increased from the Bocca Nuova on the morning at about 9.20 AM. This activity characterized by ash and gas venting was continuing over the day. Also, some glowing was visible in the late of the afternoon.As of the 18th of January, INGV reported that a new short eruptive phase occurred between 5 PM and 10:30 PM from the Bocca Nuova. This activity was accompanied by a volcanic tremor. As of the 16th of January, INGV reported that following a short stop, a brief but significant explosive activity started at about 6:56 PM. Due to bad meteorological condition no direct observation was possible, but red glowing was visible above the summit zone. As of the 15th of January, INGV reported that the intense Strombolian activity within Etna's Bocca Nuova, which started early on 10 Jnuary 2013, continued for five days and then ended during the early morning hours of 15 January. At night during the past few days, in conditions of good visibility, the activity was well visible from population centers around the volcano; often the jets of incandescent bombs rose many tens of meters above the crater rim. On the evening of 14 January, the activity was particularly intense, with jets that reached about 100 m above the crater rim As of the 11th of January, INGV reported that strombolian activity is still continuing from the Bocca Nuova crater. Tremor signal remains at a high level. (webcam).Three months after the latest episode of intracrater Strombolian and effusive activity of Etna's Bocca Nuova, vigorous Strombolian activity started during the night of 9-10 January 2013. Starting around 23:00 GMT (=local time -1) on 9 January, the INGV-Osservatorio Etneo seismic surveillance network showed a rapid rise in the volcanic tremor amplitude, in particular at the "ECPN" (Etna Cratere del Piano) station, which among the currently functioning stations station is the one closest to Bocca Nuova. At 23:10 GMT, the high-sensitivity visual surveillance camera on the Montagnola (EMOH) recorded a first brief, and weak burst of incandescence coming from the eastern part of the crater. This was followed by others, which progressively became stronger and more frequent. From 02:50 GMT on, jets of incandescent lava fragments began to rise significantly higher than the crater rim, producing also small anomalies in images recorded by the thermal surveillance camera on the Montagnola (EMOT). The images at left show some of these jets, which between 04:00 and 05:30 GMT reached heights of 50-80 m above the crater rim. With daylight, the phenomenon was no longer visible via the surveillance cameras; however, throughout the morning the volcanic tremor amplitude remained elevated but started to show a diminution around noon. This crater has been erupting intermittently since July 2011, and more vigorously so since July 2012; the latest episode of Strombolian activity and intracrater lava flows was in early October 2012. . www.ct.ingv.it . Live cam Etna - Etna monitoring page ************************************************************************************************************************* ITALY - Stromboli volcano (Eolian Islands) April 18th , 2013
A new episode of spattering and low lava fountaining started on the afternoon of 17 April 2013 at the small cone sitting on the northwestern rim of the crater terrace, producing a well-fed lava overflow onto the northwestern portion of the Sciara del Fuoco. Differently from earlier communications, the lava flow has not reached the shore at the base of the Sciara del Fuoco, but the active lava flow front currently are at about 500 m elevation. As of 07:30 GMT on 13 April 2013, the activity is continuing without significant variations. A second episode of lava
overflow started on the evening of 1 March and ceased the next afternoon.
Both overflows were fed by continuous spattering from vent N2, which lies
at the top of a hornito perched on the N rim of the crater terrace. As of the 28th of February, INGV reported that the lava overflow from the crater terrace, which began on the afternoon of 27 February, ceased during the late evening of the same day. Sezione di Catania - Osservatorio Etneo reported that a new phase of
intermittent effusive activity at Stromboli, which consisted of small
overflows of lava from the crater terrace, began on 8 February and
continued until the morning of 17 February. During this interval several
episodes of effusive activity occurred in the N and NW sectors of the
Sciara del Fuoco, producing lava flows that traveled several tens to a few
hundred meters.
Lava overflows ceased on the afternoon of 10 February, but effusive
activity resumed in the early morning hours of the next day. On the
afternoon of 11 February, three small lava flows were visible on the upper
slope of the Sciara del Fuoco; the westernmost flow traveled a few hundred
meters. That evening two of these flows remained active and continued to be
fed until the morning of 12 February. The more westerly of the flows then
stopped, whereas the flow traveling N continued until the early afternoon.
After an interval of non-visibility due to inclement weather conditions, a
new lava flow traveled NW in the evening of 12 February. This flow
progressively diminished, but was still active at about 1100 on 13
February. On 9 February Sezione di Catania - Osservatorio Etneo reported that after
about three weeks of normal explosive activity, new, small lava overflows
again occurred on Stromboli's crater terrace. The first overflow started in
the morning of 8 February, producing a small lava flow that descended the
upper NW slope of the Sciara del Fuoco, and ceased during the afternoon.
The second overflow began shortly after midnight on 9 February and produced
a lava flow that traveled N. Bad weather prevented surveillance video
transmission after 0125; when the transmission resumed at 1000, the feeding
of the lava flow had diminished, and the active flow front was retreating
upslope, generating frequent rockfalls. In the late afternoon of 9 February
lava effusion ceased altogether, but resumed once more during the early
morning hours of 10 February, generating a small flow that slowly advanced
downslope for a few tens of meters. The lava front continuously produced
incandescent rockfalls. During the day, lava emission progressively
diminished, and ceased completely in the late afternoon. As of the 18th of January, INGV reported that
the volcano was still erupting with lava flows went down to the Sciara del Fuoco. There is no signs of stopping for the moment.
At daybreak on 15 January, only a small lava flow was active, but on the afternoon the effusion rate once more increased, feeding a flow that was well visible at sunset.
Around 04:20 GMT on 14 January, a second lava lobe developed next to the already active flow, but further to the north, reaching a length of about 100 m ; after one hour, the lobe was no longer fed and started cooling. The main lava flow, however, continued its downslope movement without significant variations, and around 06:20 GMT another overflow began to take the same path as the small lobe of 04:20 GMT. This time supply of lava to the flow was rather vigorous, forming a fan-shaped lobe (Fig. 6, top right), which descended rapidly next to the earlier main flow. During the daylight hours, interaction of hot material from the lava flow and sea water generated dense vapor clouds, mixed with ash generated by numerous small landslides; these phenomena reached their maximum intensity during the early afternoon. At dusk, three lava flows were active on the upper slope of the Sciara; of these, only one remained active on the late evening
As of the 13th of january, INGV reported that on the late evening of 13 January, renewed lava effusion started to produce an overflow toward northwest, which continued in a pulsating manner through the night, intensifying notably after 03:30 GMT on 14 January. Since the morning of 23 December 2012, there have been repeated lava overflows from the crater terrace of Stromboli, generating small lava flows down the northern and northwestern sectors of the Sciara del Fuoco (see images below). Furthermore, the rapid accumulation of fluid spatter during intense explosive activity often generated small flows; these phenomena were accompanied by numerous landslides. The major lava flows occurred on the evening of 23 December (toward north), on 25-27 December 2012 (toward northwest), and on the morning of 7 January 2012 (toward northwest). Lava emission occurred from vents lying just below the rim of the northernmost explosive vent on the crater terrace. During the intervals between the main effusive episodes, lava was extruded at extremely low rates from the effusive vents, resulting in the descent of numerous incandescent blocks down the Sciara. At times, small lava flows advanced for a few tens of meters before disintegrating into blocks, such as on the morning of 10 January 2013 (see the last photo in the sequence below). In all cases, the effusion of lava was preceded, and often accompanied, by intense explosive activity on the crater terrace
. e
Spectacular incandescent nighttime explosions at
Stromboli volcano have long attracted visitors to the "Lighthouse of the
Mediterranean."Stromboli, the NE-most of the Aeolian Islands, has lent its
name to the frequent mild explosive activity that has characterized its
eruptions throughout historical time. The small, 926-m-high island of
Stromboli is the emergent summit of a volcano that grew in two main
eruptive cycles, the last of which formed the western portion of the
island. The active summit vents are located at the head of the Sciara del
Fuoco, a horseshoe-shaped scarp formed as a result of slope failure that
extends to below sea level and funnels pyroclastic ejecta and lava flows to
the NW. Essentially continuous mild Strombolian explosions, sometimes
accompanied by lava flows, have been recorded at Stromboli since Roman ************************************************************************************************************************* ICELAND - Hekla Volcano April 2nd, 2013 On 29 March the Icelandic Meteorological Office noted that Hekla had been
quiet the previous few days; no additional earthquakes had been detected
since a period of increased seismicity during 10-26 March. The Icelandic
Civil Defense continued to maintain a level of "uncertainty".
The Icelandic Meteorological Office noted that since 10 March, at least
seven micro-earthquakes at Hekla, ranging in size from M 0.4 to 1, had been
detected within a small area about 4.5 km NE of the summit, at depths of
11-12 km. These earthquakes were high-frequency, suggestive of brittle
fracturing rather than magma movement. At Hekla, such a clustering of
earthquakes is unusual in between eruptions. Continuous measurements of
borehole strain and ground-based GPS showed no changes in crustal
deformation.
On 26 March the Icelandic Meteorological Office increased the Aviation
Colour Code from Green to Yellow, because of the increased seismic
activity. Icelandic Civil Defense together with the Police in Hvolsvöllur
had also declared a level of uncertainty for Hekla, although there were no
observable signs that an eruption of Hekla was imminent.
One of Iceland's most prominent and active volcanoes,
Hekla lies near the southern end of the eastern rift zone. Hekla occupies a
rift-transform junction, and has produced basaltic andesites, in contrast
to the tholeiitic basalts typical of Icelandic rift zone volcanoes.
Vatnafjöll, a 40-km-long, 9-km-wide group of basaltic fissures and crater
rows immediately SE of Hekla forms a part of the Hekla-Vatnafjöll volcanic
system. A 5.5-km-long fissure, Heklugjá, cuts across the 1491-m-high Hekla
volcano and is often active along its full length during major eruptions.
Repeated eruptions along this rift, which is oblique to most rifting
structures in the eastern volcanic zone, are responsible for Hekla's
elongated ENE-WSW profile. Frequent large silicic explosive eruptions
during historical time have deposited tephra throughout Iceland, providing
valuable time markers used to date eruptions from other Icelandic
volcanoes. Hekla tephras are generally rich in fluorine and are
consequently very hazardous to grazing animals. Extensive lava flows from
Hekla's historical eruptions, which date back to 1104 AD, cover much of the
volcano's flanks. (GVN7GVP) SPAIN - Hierro island (Canary) April 2nd, 2013 On 18 March seismic activity at El Hierro sharply increased. Earthquakes
were initially located around the NW tip of the island, at about 20 km
depth, then later migrated W about 12-15 km offshore W of El Hierro Island,
at similar depth. About 100 earthquakes of Mb 3.5 (body wave measurement)
or greater had been located, many of them felt by residents. The biggest
events occurred on 29 March (Mb 4.7) and 31 March (Mw 4.6, moment
magnitude) both at 20 km depth. IGN's GPS data showed inflation of the
island, with maximum deformation at the westernmost station of about 10 cm
in the horizontal component and about 11 cm in the vertical. Deformation
rates reached a maximum during 23-24 March. An increase in carbon dioxide |
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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 Brűlé 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 *********************************************************************************************************** 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 .*********************************************************************************************************** TANZANIE - Lengai volcano October 30th, 2012 News and recent photos taken in September 2012 at the summit crater. Previously, as of the 22nd of February 2010 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. ********************************************************************************************************* 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. November 2nd, 2012 The Toulouse VAAC reported that, according to a Volcano Observatory Notices
for Aviation (VONA) issued by the Goma Volcano Observatory, a gas plume
composed mostly of sulfur dioxide rose from Nyiragongo on 1 November. Previously 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) 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. **************************************************************************************************************************** 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 February 5th, 2012 According to a member of Activ website, and following a recently 2012 fieldtrip a lava lake lies within the South pit-crater of the Erta Ale caldera. This lake was about 15 m depth with 50-60 m diameter. Important degassing occured from incandescent hornitos within the North pit-crater. News 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 May 9th, 2013 At 0800 on 8 May, PHIVOLCS reported that two rockfalls at Mayon had been
detected within the previous 24 hours. Seismicity remained within
background levels and indicated no increase in overall volcanic activity. 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 April 28h, 2012 As of the PHIVOLCS reported that the Alert Level for Bulusan was lowered to 0 (on a scale of 0-5) on 24 April following a decline in activity after a phreatic eruption on 13 May 2011. The frequency of earthquakes decreased to baseline levels of 0-2 per day, measurements indicated deflation since late November 2011, and steaming activity from the crater and known thermal vents had been frequently weak compared to more moderate steam emissions during periods of unrest. Entry into the permanent danger zone, defined by a 4-km radius around the volcano, remained prohibited. 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 2012 - 2013 Tangkubanparahu volcano ( Java) - CVGHM reported that phreatic eruptions from Tangkubanparahu's Ratu Crater occurred on 28 February 2013 and during 4-6 March, and generated ash plumes that rose up to 100 m above the crater. Sulfur dioxide emissions increased to a high level on 24 February and then decreased through 3 March. Sulfur dioxide emissions again increased during 5-9 March; CVGHM speculated that the increase was due to an enlargement of the eruptive vent, which had grown to a diameter of 20 m. Gas emissions decreased abruptly on 10 March and emission sounds stopped. Seismicity had significantly increased on 22 February, marked by a growing number of daily events. A significant decrease was detected on 9 March. Deflation was detected from 24 February through early March, but was then stable during 7-14 March. On 18 March the Alert Level was lowered to 1 (on a scale of 1-4). CVGHM reported that on 21 February tremor increased at tangkubanparahu and diffuse ash emissions rose from Ratu Crater. Based on the seismicity, visual observations, and temperature increases of the land around the crater, the Alert Level was raised to 2 (on a scale of 1-4) and visitors were reminded not to approach the crater within a radius of 1.5 km. Tangkubanparahu is a broad shield-like stratovolcano overlooking Indonesia's former capital city of Bandung that was constructed within the 6 x 8 km Pleistocene Sunda caldera. The volcano's low profile is the subject of legends referring to the mountain of the "upturned boat." The rim of Sunda caldera forms a prominent ridge on the western side; elsewhere the caldera rim is largely buried by deposits of Tangkubanparahu volcano. The dominantly small phreatic historical eruptions recorded since the 19th century have originated from several nested craters within an elliptical 1 x 1.5 km summit depression. Tangkubanparahu last erupted in September 1983, when ash rose up to 150 m above the rim of Kawah Ratu. (GVN/GVP) Dieng volcano complex (Java) -
CVGHM reported that on 28 March 2013 gas emissions continued to be elevated at
Timbang, a cone that is part of the Dieng Volcanic Complex. Plumes
containing carbon dioxide drifted 2 km towards the S valley of Kali Sat,
prompting a road closure until the early evening when the gas concentration
decreased. On 30 March carbon dioxide gas emissions were not detected;
however, "smoke" rose at most 100 m above the crater. Hydrogen sulfide
odors were very potent in areas 1 km W and weak in areas 1.5 km S. On 19
April sulfur dioxide odors were reported.
On 24 March Sileri Crater lake water changed from dark gray to brown. On 7
April white plumes rose 50 m and the water color returned to normal. Guntur volcano (Java) - CVGHM reported that in early March 2013 a slight increase of deep and shallow
volcanic-tectonic earthquakes at Guntur was recorded; volcanic tremor
became continuous on 2 April, prompting CVGHM to raise the Alert Level to 2
(on a scale of 1-4).
Temperature measurements of hot springs in five different areas fluctuated
until mid-April and then were relatively stable through early May.
Seismicity also decreased in early May. On 7 May the Alert Level was
lowered to 1.
Guntur is a complex of several overlapping
stratovolcanoes about 10 km NW of the city of Garut in western Java. Young
lava flows, the most recent of which was erupted in 1840, are visible on
the flanks of the erosionally unmodified Gunung Guntur, which rises about
1,550 m above the plain of Garut. Guntur is one of a group of younger cones
constructed to the SW of an older eroded group of volcanoes at the NE end
of the complex. Guntur, whose name means "thunder," is the only
historically active center, with eruptions having been recorded since the
late-17th century. Although Guntur produced frequent explosive eruptions in
the 19th century, making it one of the most active volcanoes of western
Java, it has not erupted since. (GVN/GVP) Mount Semeru ( Java) -
CVGHM reported that during 1-29 February 2012 multiple pyroclastic flows from Mount Galunggung (Java) -CVGHM reported that, since the Alert Level was raised on 12 February, Paluweh volcano (Lesser Sunda Islands) - Based on analyses of satellite imagery and wind data, the Darwin VAAC reported that on 13 May 2013 ash plumes from Paluweh rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted over 90 km WNW and NW. Based on analyses of satellite imagery and wind data, the Darwin VAAC reported that during 4-5 May 2013 ash plumes from Paluweh rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted 45-55 km SW and W. Based on analyses of satellite imagery and wind data, the Darwin VAAC reported that during 29-30 April ash plumes from Paluweh rose to altitudes of 2.1-3 km (7,000-10,000 ft) a.s.l. and drifted 35-110 km NW and W.Based on analyses of satellite imagery and wind data, the Darwin VAAC reported that on 20 April an ash plume from Paluweh rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted 45 km NW.Based on analyses of satellite imagery and wind data, the Darwin VAAC reported that on 16 April an ash plume from Paluweh rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted 37 km E. During 6-7 April ash plumes rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted over 45 km W and WSW. Based on analyses of satellite imagery and wind data, the Darwin VAAC reported that during 27 March-1 April ash plumes from Paluweh rose to altitudes of 2.4-3.7 km (8,000-12,000 ft) a.s.l. and drifted 45-100 km N, NE, and E. Based on analyses of satellite imagery and wind data, the Darwin VAAC reported that during 19-21 and 24-26 March ash plumes from Paluweh rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted 55-335 km SW, WSW, W, NW, and NE. Based on analyses of satellite imagery and wind data, the Darwin VAAC reported that during 13 and 17-19 March ash plumes from Paluweh rose to altitudes of 2.4 km (7,000-13,000 ft) a.s.l. and drifted 35-95 km E, W, and WNW.Based on analyses of satellite imagery and wind data, the Darwin VAAC reported that during 9-12 March ash plumes from Paluweh rose to altitudes of 2.4 km (7,000-13,000 ft) a.s.l. and drifted 25-75 km E and NW. Based on analyses of satellite imagery and wind data, the Darwin VAAC reported that during 17-18 February ash plumes rose to an altitude of 7 km (13,000 ft) a.s.l. and drifted 75 km E and NE. On 2 February an explosion produced an ash plume that rose 4 km and was accompanied by booms and rumbling. The ash plume drifted S and deposited ashfall up to 1 mm thick in Ende (60 km S); thick ashfall was reported in Ona (SE part of the island) and thin deposits were reported in other areas of the island to the W, N, and E. About 25% of the S portion of the dome was lost; the lava-dome volume was an estimated 5.1 million cubic meters on 13 January.(lava dome video) .On 3 February an ash eruption was observed as well as incandescence from the crater. During 4-10 February diffuse white plumes rose 50-100 m. The Alert Level remained at 3 (on a scale of 1-4), and visitors and residents were prohibited from approaching the crater within a 3-km-radius. NE. (satellite image). Due to the growing lava dome several valley located West and Southwest around now could be impacted in addition to the South open valley Several villages are directly threatened with the eruptive activity (Nitunglea, Rokirole, Tuanggeo, Ona, Wolondopo). Ashfalls also could be occurs around the volcano. Based on analyses of satellite imagery and wind data, the Darwin VAAC reported that during 8-12 February ash plumes from Paluweh rose to altitudes of 2.1-3.7 km (7,000-12,000 ft) a.s.l. and drifted 35-110 km NW, NNW, and N. According to news articles, an explosion from Paluweh occurred at 2300 on 2 February and was clearly heard by local residents. Authorities evacuated by boat all residents from the eight villages on the island. Ashfall was reported during 2-3 February. Paluweh volcano, also known as Rokatenda, forms the 8-km-wide island of Paluweh N of the volcanic arc that cuts across Flores Island. Although the volcano rises about 3,000 m above the sea floor, its summit reaches only 875 m above sea level. The broad irregular summit region contains overlapping craters up to 900 m wide and several lava domes. Several flank vents occur along a NW-trending fissure. The largest historical eruption of Paluweh occurred in 1928, when a strong explosive eruption was accompanied by landslide-induced tsunamis and lava-dome emplacement. (GVN/GVP) Sangang Api ( Lesser Sunda islands) -
CVGHM reported that during 1-19 May 2013 diffuse white plumes rose 10 m above
Sangeang Api's crater. Both the lava dome and surrounding areas showed no
changes since November 2012. Seismicity had increased on 26 April and
remained high. The Alert Level was raised to 3 (on a scale of 1-4) on 19
May. Residents and tourists were advised not to approach the craters within
a radius of 5 km.
Sangeang Api volcano, one of the most active in the
Lesser Sunda Islands, forms a small 13-km-wide island off the NE coast of
Sumbawa Island. Two large trachybasaltic-to-tranchyandesitic volcanic
cones, 1949-m-high Doro Api and 1795-m-high Doro Mantoi, were constructed
in the center and on the eastern rim, respectively, of an older, largely
obscured caldera. Flank vents occur on the south side of Doro Mantoi and
near the northern coast. Intermittent historical eruptions have been
recorded since 1512. Dukono (Halmahera) - Based on analyses of satellite imagery, the Darwin VAAC reported that on 18 June an ash plume from Dukono rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted 110 km W. An ash plume rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted almost 85 km W on 19 June. Based on analyses of satellite imagery, the Darwin VAAC reported that on 25 May an ash plume from Dukono rose to an altitude of 4.5 km (14,000 ft) a.s.l. and drifted 185 km E. Ash plumes again rose to an altitude of 4.5 km (14,000 ft) a.s.l. drifting 130 km E on 27 May and 93 km NE on 28 May. An ash plume rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted 75 km NE during 28-29 May. Based on analyses of satellite imagery, the Darwin VAAC reported that on 18 May an ash plume from Dukono rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted 55 km E. Based on analyses of satellite imagery, the Darwin VAAC reported that during 8-9 May ash plumes from Dukono rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted 75 km SE. 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)-
Based on analyses of satellite imagery and wind data, the Darwin VAAC Anak Krakatau (
Sunda Strait) -
According to NASA's Earth Observatory, a satellite image of Krakatau Soputan volcano
(Sulawesi) -
CVGHM reported that seismicity at Soputan increased during January-18 April
2013 and then significantly increased on 19 April. The Alert Level was raised to
3 (on a scale of 1-4) on 19 April. Visitors and residents were prohibited
from going within a 6.5-km radius of the crater. Batu Tara volcano (Flores) -
Based on analyses of satellite imagery and wind data, the Darwin Volcanic Lewotobi volcano (Flores Island) -
CVGHM reported that seismicity at Lewotobi Lakilaki, one of two |
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RUSSIA - Bezymianny volcano (Kamchatka) February 10th, 2013 KVERT reported that during 1-8 February seismic activity at Bezymianny was obscured by strong seismicity at Tolbachik. A viscous lava flow continued to effuse on the lava-dome flank, accompanied by gas-and-steam emissions. A thermal anomaly was detected in satellite imagery on 31 January and 1 February; cloud cover prevented views on the other days. As of the 3rd of September, KVERT reported that Based on seismic data analyses, an explosive eruption occurred from 0716 to 0745 on 2 September. Ash plumes rose to altitudes of 10-12 km and drifted more than 1,500 km ENE. A thermal anomaly observed in satellite imagery was very bright before the explosion. Ash plumes rose to an altitude of 4 km (13,100 ft) a.s.l. and drifted NE later that day, then ash emissions ceased. Ash plumes continued to be detected in satellite imagery and drifted 450-600 km ENE and SE. The Aviation Color Code was lowered to Yellow. On 3 September seismic activity was low. A viscous lava flow effused on the lava-domeflank, and was accompanied by fumarolic activity and hot avalanches. (photos). During 9-13 March strong gas-and-steam emissions were noted, a viscous lava flow effused onto the lava-dome flank, and a thermal anomaly continued to be detected in satellite imagery. The Aviation Color Code was lowered to Orange on 14 March. As of the 9th of March, KVERT reported that a strong explosive eruption began at 21:27 UTC on March 08. According to seismic data, the culmination phase of the eruption occurred from 21:27 till 22:10 UTC on March 08, a magnitude of volcanic tremor was 7.52 µm/s at that time. From 23:00 UTC on March 08, volcanic tremor was not registering. Ash plumes from pyroclastic deposits rose up to 26,200 ft (8 km) a.s.l. and extended to the northeast of the volcano on the height about 19,700 ft (6 km) a.s.l. At about 00:15 UTC on March 09, probably a new portion of ash began to extending a little to northern to northeast of the volcano. According to satellite data, a length of ash plume was about 434 mi (700 km) at 04:32 UTC on March 09. According to video data, gas-steam plumes containing ash are raising up to 11,500-13,100 ft (3.5-4.0 km) a.s.l. and extending to the north-east of the volcano.(MODIS image) Ashfall was reported in Ust-Kamchatsk Village (120 km ENE). Later that day activity decreased significantly and the Aviation Color Code was lowered to Orange. Previous news - Seismic activity increased on February 12 and remained the same till February 29: about 7-19 weak seismic events were registering each day. There were 40 weak seismic events on March 01 and 25 events on March 02. Long episode of volcanic tremor was registered on March 02. Probably an extrude of lava blocks at the top of the dome occur, that prepares a strong explosive eruption of the volcano. According to satellite data, a size and a brightness of a thermal anomaly abrupt increased on March 02 (at 09:35 UTC on March 02, a temperature of the thermal anomaly was +53.4 degrees of Celsius). Density clouds obscured the volcano on March 02. Seismic activity increased on February 12 and remains the same till now: about 9-17 weak seismic events are registering each day. Two short episodes of volcanic tremor were registered on February 15 and 22. Probably an extrude of lava blocks at the top of the dome occur, that prepares a strong explosive eruption of the volcano. A strong and moderate gas-steam activity was observed at the volcano all week. According to satellite data, a thermal anomaly over the volcano continues to noting on the satellite images; gas-steam plumes were extending to the northeast of the volcano on February 20 and 22. 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. (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) May 20th, 2013 Based on visual observations and analyses of satellite data, KVERT reported that during 10-16 May a viscous lava flow effused on the N flank of Shiveluch's lava dome, accompanied by hot avalanches, incandescence, and fumarolic activity. Satellite imagery showed a daily thermal anomaly on the lava dome. The Aviation Color Code remained at Orange. Based on analyses of satellite imagery and notices from Yelizovo Airport (UHPP), the Tokyo VAAC reported that on 18 May ash plumes rose to an altitude of 5.5 km (18,000 ft) a.s.l. and drifted NE. Based on visual observations and analyses of satellite data, KVERT reported that during 3-10 May a viscous lava flow effused on the NW and NE flanks of Shiveluch's lava dome, accompanied by hot avalanches, incandescence, and fumarolic activity. Satellite imagery showed a daily thermal anomaly on the lava dome. The Aviation Color Code remained at Orange.Based on visual observations and analyses of satellite data, KVERT reported that during 26 April-3 May a viscous lava flow effused on the NW and NE flanks of Shiveluch's lava dome, accompanied by hot valanches, incandescence, and fumarolic activity. Satellite imagery showed a daily thermal anomaly on the lava dome. The Aviation Color Code remained at Orange. Based on analyses of satellite imagery and notices from Yelizovo Airport (UHPP), the Tokyo VAAC reported that on 5 May an ash plume rose to an altitude of 4.6 km (15,000 ft) a.s.l. and drifted E. Based on visual observations and analyses of satellite data, KVERT reported that during 19-26 April a viscous lava flow effused on the NW flank of Shiveluch's lava dome, accompanied by hot avalanches, incandescence, and fumarolic activity. Satellite imagery showed a daily thermal anomaly on the lava dome. The Aviation Color Code remained at Orange. Based on visual observations and analyses of satellite data, KVERT reported that during 12-19 April a viscous lava flow effused on the NW flank of Shiveluch's lava dome, accompanied by hot avalanches, incandescence, and fumarolic activity. Satellite imagery showed a daily thermal anomaly on the lava dome. Based on analyses of satellite imagery, the Tokyo VAAC reported that on 22 April ash plumes rose to an altitude of 3.7 km (12,000 ft) a.s.l. and drifted NE. Subsequent images that day showed that the ash had dissipated. The Aviation Color Code remained at Orange. Based on visual observations and analyses of satellite data, KVERT reported that during 5-12 April a viscous lava flow effused on the E flank of Shiveluch's lava dome, accompanied by hot avalanches, incandescence, and fumarolic activity. Satellite imagery showed a daily thermal anomaly on the lava dome. The Aviation Color Code remained at Orange. 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) May 5th, 2013 KVERT reported that satellite data showed a thermal anomaly on Karymsky on 26 April. Two streaks of ash deposits near the volcano were observed during 1-2 May: about 15 km to the W and about 30 km to the NW of the volcano. Technical problems prevented seismic data collection during 26 April-3 May. The Aviation Color Code remained at Orange. KVERT reported that satellite data showed a thermal anomaly on Karymsky on 1 and 3 April. Technical problems prevented seismic data collection. The Aviation Color Code remained at Orange. KVERT reported that weak-to-moderate seismic activity at Karymsky was detected during 15-22 March. Satellite data showed a weak thermal anomaly on the volcano on 18 March. The Aviation Color Code remained at Orange. KVERT reported that weak-to-moderate seismic activity at Karymsky was detected during 8-15 March. Satellite data showed that the volcano was quiet. The Aviation Color Code remained at Orange. KVERT reported that moderate seismic activity at Karymsky was detected during 28 February-7 March. The Aviation Color Code remained at Orange. 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.
March 20th, 2013 KVERT reported that activity at Kliuchevskoi decreased in late 2012, around the same time the Tolbachik eruption started. In mid-January 2013 seismic activity decreased and Strombolian activity ceased. Starting in February incandescence at the summit and thermal anomalies were not observed. Weak seismic activity continued. On 18 March the Aviation Color Code was lowered to Green, the lowest level. KVERT reported that during 18-25 January video footage and satellite imagery showed Strombolian explosions at Kliuchevskoi, along with crater incandescence and gas-and-steam emissions. Views from satellite were obscured by cloud cover. The Aviation Color Code remained at Orange.Previously KVERT reported that during 14-21 December 2012 video footage and satellite imagery showed Strombolian explosions at Kliuchevskoi, along with crater incandescence and gas-and-steam emissions. A thermal anomaly was detected in satellite images on 16 and 18 December; cloud cover obscured views on the other days. The Aviation Color Code remained at Orange.KVERT reported that during 7-14 December video footage and satellite imagery showed Strombolian explosions at Kliuchevskoi, along with crater incandescence and gas-and-steam emissions. A thermal anomaly was detected in satellite images during 7-8, 10, and 12-13 December; cloud cover obscured views on the other days. The Aviation Color Code remained at Orange. KVERT reported that during 30 November-7 December video footage and satellite imagery showed Strombolian explosions at Kliuchevskoi, along with crater incandescence and gas-and-steam emissions. A weak thermal anomaly was detected in satellite images during 1 and 4-6 December; cloud cover obscured views on the other days. 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 - Tolbalchik volcano May 18th, 2013 KVERT reported that the S fissure along the W side of Tolbachinsky Dol, a
lava plateau on the SW side of Tolbachik, continued to produce very fluid
lava flows during 10-16 May that traveled to the W, S, and E sides of the
plateau. Cinder cones continued to grow along the S fissure and gas-and-ash
plumes were observed. A large thermal anomaly on the N part of Tolbachinsky
Dol was visible daily in satellite imagery. The Aviation Color Code
remained at Orange. KVERT reported that the S fissure along the W side of Tolbachinsky Dol, a
lava plateau on the SW side of Tolbachik, continued to produce very fluid
lava flows during 3-10 May that traveled to the W, S, and E sides of the
plateau. Cinder cones continued to grow along the S fissure and gas-and-ash
plumes were observed. A large thermal anomaly on the N part of Tolbachinsky
Dol was visible daily in satellite imagery. The Aviation Color Code
remained at Orange. KVERT reported that the S fissure along the W side of Tolbachinsky Dol, a
lava plateau on the SW side of Tolbachik, continued to produce very fluid
lava flows during 26 April-3 May that traveled to the W, S, and E sides of
the plateau. Cinder cones continued to grow along the S fissure and
gas-and-ash plumes were observed. A large thermal anomaly on the N part of
Tolbachinsky Dol was visible daily in satellite imagery. The Aviation Color
Code remained at Orange. KVERT reported that the S fissure along the W side of Tolbachinsky Dol, a
lava plateau on the SW side of Tolbachik, continued to produce very fluid
lava flows during 19-26 April that traveled to the W, S, and E sides of the
plateau. Cinder cones continued to grow along the S fissure. Gas-and-ash
plumes rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted in
multiple directions. A large thermal anomaly on the N part of tolbachinsky
Dol was visible daily in satellite imagery. The Aviation Color Code
remained at Orange. KVERT reported that the S fissure along the W side of Tolbachinsky Dol, a
lava plateau on the SW side of Tolbachik, continued to produce very fluid
lava flows during 12-19 April that traveled to the W, S, and E sides of the
plateau. Cinder cones continued to grow along the S fissure. Gas-and-ash
plumes rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted in
multiple directions. A large thermal anomaly on the N part of Tolbachinsky
Dol was visible daily in satellite imagery. The Aviation Color Code
remained at Orange. KVERT reported that the S fissure along the W side of Tolbachinsky Dol, a
lava plateau on the SW side of Tolbachik, continued to produce very fluid
lava flows during 5-12 April that traveled to the W, S, and E sides of the
plateau. Cinder cones continued to grow along the S fissure. Gas-and-ash
plumes rose to an altitude of 3.5 km (11,500 ft) a.s.l. and drifted in
multiple directions. A very large thermal anomaly on the N part of
Tolbachinsky Dol was visible daily in satellite imagery. A weak thermal
anomaly was detected over the crater of the volcano on 6 and 9 April. The
Aviation Color Code remained at Orange. KVERT reported that the S fissure along the W side of Tolbachinsky Dol, continued to produce very fluid
lava flows during 29 March-5 April that traveled to the W, S, and E sides
of the plateau. Cinder cones continued to grow along the fissure.
Gas-and-ash plumes rose to an altitude of 3.5 km (11,500 ft) a.s.l. and
drifted in multiple directions. A very large thermal anomaly on the N part
of Tolbachinsky Dol was visible daily in satellite imagery. The Aviation
Color Code remained at Orange.
KVERT reported that the S fissure along the W side of Tolbachinsky Dol, a
lava plateau on the SW side of Tolbachik, continued to produce very fluid
lava flows during 22-29 March that traveled to the W, S, and E sides of the
plateau. Cinder cones continued to grow along the fissure. Gas-and-ash
plumes rose to an altitude of 3.5 km (11,500 ft) a.s.l. and drifted in
multiple directions. A very large thermal anomaly on the N part of
Tolbachinsky Dol was visible daily in satellite imagery. The Aviation Color
Code remained at Orange.
KVERT reported that the S fissure along the W side of Tolbachinsky Dol, a
lava plateau on the SW side of Tolbachik, continued to produce very fluid
lava flows during 15-22 March that traveled to the W, S, and E sides of the
plateau. Cinder cones continued to grow along the fissure. Gas-and-ash
plumes rose to an altitude of 3.5 km (11,500 ft) a.s.l. and drifted in
multiple directions. A very large thermal anomaly on the N part of
Tolbachinsky Dol was visible daily in satellite imagery. The Aviation Color
Code remained at Orange.
KVERT reported that the S fissure along the W side of Tolbachinsky Dol, continued to produce very fluid
lava flows during 8-15 March that traveled to the W, S, and E sides of the
plateau. Cinder cones continued to grow along the fissure. Gas-and-ash
plumes rose to an altitude of 3.5 km (11,500 ft) a.s.l. and drifted in
multiple directions. A very large thermal anomaly on the N part of
Tolbachinsky Dol was visible daily in satellite imagery. The Aviation Color
Code remained at Orange.
KVERT reported that the S fissure along the W side of Tolbachinsky Dol, continued to produce very fluid
lava flows during 28 February-7 March that traveled to the W, S, and E
sides of the plateau. Cinder cones continued to grow along the fissure.
Gas-and-ash plumes rose to an altitude of 3.5 km (11,500 ft) a.s.l. and
drifted in multiple directions. A very large thermal anomaly on the N part
of Tolbachinsky Dol was visible daily in satellite imagery. The Aviation
Color Code remained at Orange.
KVERT reported that the S fissure along the W side of Tolbachinsky Dol, continued to produce very fluid
lava flows during 22 February-1 March that traveled to the W, S, and E
sides of the plateau. Cinder cones continued to grow on the fissure.
Gas-and-ash plumes rose to an altitude of 3.5 km (11,500 ft) a.s.l. and
drifted in multiple directions. A very large thermal anomaly on the N part
of Tolbachinsky Dol was visible daily in satellite imagery. The Aviation
Color Code remained at Orange.
KVERT reported that the S fissure along the W side of Tolbachinsky Dol, a
lava plateau on the SW side of Tolbachik, continued to produce very fluid
lava flows during 15-22 February that traveled to the W, S, and SE sides of
the plateau. Four cinder cones continued to grow on the S fissure above
Krasny cone. Gas-and-ash plumes rose to an altitude of 3.5 km (11,500 ft)
a.s.l. and drifted in multiple directions. A very large thermal anomaly on
the N part of Tolbachinsky Dol was visible daily in satellite imagery. The
Aviation Color Code remained at Orange. KVERT reported that the S fissure along the W side of Tolbachinsky Dol, a
lava plateau on the SW side of Tolbachik, continued to produce very fluid
lava flows during 8-15 February that traveled to the W, S, and SE sides of
the plateau. Four cinder cones continued to grow on the S fissure above
Krasny cone. Gas-and-ash plumes rose to an altitude of 3.5 km (11,500 ft)
a.s.l. and drifted in multiple directions. A very large thermal anomaly on
the N part of Tolbachinsky Dol was visible daily in satellite imagery. The
Aviation Color Code remained at Orange. KVERT reported that the S fissure along the W side of Tolbachinsky Dol, a
lava plateau on the SW side of Tolbachik, continued to produce very fluid
lava flows during 1-8 February that traveled to the W and S sides of the
plateau. Four cinder cones continued to grow on the S fissure above Krasny
cone. Gas-and-ash plumes rose to an altitude of 3.5 km (11,500 ft) a.s.l.
and drifted in multiple directions. A very large thermal anomaly on the N
part of Tolbachinsky Dol was visible daily in satellite imagery. The
Aviation Color Code remained at Orange. KVERT reported that the S fissure along the W side of Tolbachinsky Dol, a
lava plateau on the SW side of Tolbachik, continued to produce very fluid
lava flows during 25 January-1 February that traveled to the W and S sides
of Tolbachinsky Dol. Four cinder cones continued to grow on the S fissure
above Krasny cone. Gas-and-ash plumes rose to an altitude of 3.5 km (11,500
ft) a.s.l. and drifted in multiple directions. A very large thermal anomaly
on the N part of Tolbachinsky Dol was visible daily in satellite imagery.
The Aviation Color Code remained at Orange. KVERT reported that the S fissure along the W side of Tolbachinsky Dol, a
lava plateau on the SW side of Tolbachik, continued to produce very fluid
lava flows during 18-25 January that traveled to the W and S sides of
Tolbachinsky Dol. Four cinder cones continued to grow on the S fissure
above Krasny cone. Gas-and-ash plumes rose to an altitude of 4 km (13,100
ft) a.s.l. and drifted in multiple directions. A very large thermal anomaly
on the N part of Tolbachinsky Dol was visible daily in satellite imagery.
The Aviation Color Code remained at Orange. KVERT reported that the S fissure along the W side of Tolbachinsky Dol, a
lava plateau on the SW side of Tolbachik, continued to produce very fluid
lava flows during 11-18 January that traveled to the W and S sides of
Tolbachinsky Dol. Gas-and-ash plumes rose to an altitude of 4 km (13,100
ft) a.s.l. and drifted in multiple directions. A very large thermal anomaly
on the N part of Tolbachinsky Dol was visible daily in satellite imagery.
The Aviation Color Code remained at Orange. KVERT reported that the S fissure along the W side of Tolbachinsky Dol, a
lava plateau on the SW side of Tolbachik, continued to produce very fluid
lava flows during 4-15 January that traveled to the W and SE sides of
Tolbachinsky Dol. Gas-and-ash plumes rose to an altitude of 4.5 km (14,800
ft) a.s.l. and drifted in multiple directions. A very large thermal anomaly
on the N part of Tolbachinsky Dol was visible daily in satellite imagery.
The Aviation Color Code remained at Orange. KVERT reported that the S fissure along the W side of Tolbachinsky Dol, a
lava plateau on the SW side of Tolbachik, continued to produce very fluid
lava flows during 28 December-8 January. Strong seismicity was detected.
Gas-and-ash plumes drifted in multiple directions, and a fifth cone
continued to grow above the fissure. A very large thermal anomaly on the N
part of Tolbachinsky Dol was visible daily in satellite imagery. The
Aviation Color Code remained at Orange. KVERT reported that the S fissure along the W side of Tolbachinsky Dol, a
lava plateau on the SW side of Tolbachik, continued to produce very fluid
lava flows during 21-28 December. Strong seismicity was detected.
Gas-and-ash plumes drifted in multiple directions, and a fifth cone
continued to grow above the fissure. A very large thermal anomaly on the N
part of Tolbachinsky Dol was visible daily in satellite imagery. The
Aviation Color Code remained at Orange. KVERT reported that the S fissure along the W side of Tolbachinsky Dol, a
lava plateau on the SW side of Tolbachik, continued to produce very fluid
lava flows that traveled 17-20 km during 17-21 December. Strong seismicity
was detected. Gas-and-ash plumes drifted in multiple directions, and a
fifth cone grew above the fissure. A very large thermal anomaly on the N
part of Tolbachinsky Dol was visible in satellite imagery. The Aviation
Color Code remained at Orange. KVERT reported that the S fissure along the W side of Tolbachinsky Dol, a
lava plateau on the SW side of Tolbachik, continued to produce very fluid
lava flows that traveled 17-20 km during 7-17 December. Strong seismicity
was detected. Ash plumes rose less than 1 km and drifted in multiple
directions, and at least two cones grew above the fissure. A very large
thermal anomaly on the N part of Tolbachinsky Dol was visible in satellite
imagery. The Aviation Color Code remained at Orange. As of the 14th of December, KVERT reported that eruptive activity was still continuing.
Lava flows effused on the West Flank of the rift zone (Tolbachinsky Dol). The eruptive plume decreased slightly above the volcano during the past hours. As of the 12th of December, KVERT reported that
KVERT reported that the eruption from Tolbachik that began on 27 November
continued through 11 December. A very large thermal anomaly on the N part of
Tolbachinsky Dol, a lava plateau on the SW side of the volcano, was
reported daily. Lava effused from two fissures along the W side of
Tolbachinsky Dol; lava had flowed 17-20 km away from the S fissure by 7
December. Ash plumes rose less than 500 m during 1-5 December, and minor
ashfall was reported in Kozyrevsk (40 km NW) and Klyuchi (65 km NW)
villages on 3 December. Gas-and-steam plumes drifted 250 km SE on 5
December, and rose as high as 1 km during 7-11 December and drifted SW and
W. The Aviation Color Code remained at Orange. As of the 7th of December, KVERT reported that the eruption was still continuing but seemed decreasing regarding the prvious days. (photos). As of the 5th of December, KVERT reported that the eruptive activity was still continuing. On the morning, the eruptive plume rose to about 4000 m above the volcano. (image Modis).
KVERT reported that an eruption from Tolbachik that began on 27 November
continued through 30 November. Lava effused from two fissures along the W
side of Tolbachinsky Dol, a lava plateau on the SW side of the volcano, and
ash plumes rose less than 500 m on 28 November. A large thermal anomaly was
detected on the N part of Tolbachinsky Dol. On 29 November the Aviation
Color Code was raised to Red. Ash plumes rose less than 500 m and drifted
300 km ESE. Later that day seismicity decreased and the Aviation Color Code
was lowered to Orange. During 29 November-1 December Strombolian activity
and lava effusion from two fissures continued. A large thermal anomaly
continued to be detected in satellite imagery, and ashfall was reported in
Kozyrevsk (40 km NW). According to a news article on 30 November, the lava
flows destroyed two scientific base camps 10 km away. On 1 December
gas-and-steam plumes with small amounts of ash rose over 400 m.
The eruption poses no threat to the local population. Previously, KVERT reported that episodes of volcanic tremor were detected in the area
of Plosky Tolbachik during 7-10, 18, and 26 November. The number of shallow
volcanic earthquakes increased to 250 on 26 November. A strong event
occurred at 1652 on 27 November. The Aviation Color Code was raised to
Yellow. That same day observers from Kozyrevsk (40 km NW) and Lazo (50 km
SW) villages reported ash explosions and lava flows at Tolbachinsky Dol, in
the same area as the 1975 eruption (northern vents). Ashfall, 4 cm thick,
was reported in Krasny Yar (60 km NNW). The Aviation Color Code was raised
to Orange. Based on information from the Kamchatka Branch of Geophysical
Services (KGBS), the Tokyo VAAC reported that ash plumes possibly rose to
altitudes of 6.1-10.1 km (20,000-33,000 ft) a.s.l. Ash plumes were not
detected in satellite imagery. Plume altitudes were estimated based on
seismic data.
The massive Tolbachik basaltic volcano is located at the
southern end of the dominantly andesitic Kliuchevskaya volcano group. The
Tolbachik massif is composed of two overlapping, but morphologically
dissimilar volcanoes. The flat-topped Plosky Tolbachik shield volcano with
its nested Holocene Hawaiian-type calderas up to 3 km in diameter is
located east of the older and higher sharp-topped Ostry Tolbachik
stratovolcano. The summit caldera at Plosky Tolbachik was formed in
association with major lava effusion about 6500 years ago and
simultaneously with a major southward-directed sector collapse of Ostry
Tolbachik volcano. Lengthy rift zones extending NE and SSW of the volcano
have erupted voluminous basaltic lava flows during the Holocene, with
activity during the past two thousand years being confined to the narrow
axial zone of the rifts. The 1975-76 eruption originating from the
SSW-flank fissure system and the summit was the largest historical basaltic
eruption in Kamchatka. February 24th, 2012 There was not seismic data from February 05 till present by technical reasons. 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 February 19-21 at satellite images. According to visual data, a strong and moderate gas-steam activity of the volcano was observed on February 11-14; clouds obscured the volcano on the other days of week. A thermal anomaly was registering over the volcano on February 11 at satellite images. Seismic activity of the volcano remains some heightened on February 02-04; there was not seismic data from February 05 by technical reasons. 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 February 04-05 and 07 at satellite images. According to visual data, a strong and moderate y 28 and 31, and February 01-02; clouds obscured the volcano in the other days of week. A thermal anomaly was registering over the volcano on January 28 and 31, and February 02 at satellite images. 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 May 18th, 2013 KVERT reported that during 10-16 May moderate seismic activity continued at Kizimen. Video and satellite data showed that lava continued to extrude from the summit, producing incandescence, strong gas-and-steam activity, and hot avalanches on the W and E flanks. A thermal anomaly was detected daily in satellite images. The Aviation Color Code remained at Orange. KVERT reported that during 3-10 May moderate seismic activity continued at Kizimen. Video and satellite data showed that lava continued to extrude from the summit, producing incandescence, strong gas-and-steam activity, and hot avalanches on the W and E flanks. A thermal anomaly was detected daily in satellite images. The Aviation Color Code remained at Orange. KVERT reported that during 26 April-3 May l moderate seismic activity continued at Kizimen. Video and satellite data showed that lava continued to extrude from the summit, producing incandescence, strong gas-and-steam activity, and hot avalanches on the W and E flanks. A thermal anomaly was detected daily in satellite images. The Aviation Color Code remained at Orange.KVERT reported that during 19-26 April moderate seismic activity continued at Kizimen. Video and satellite data showed that lava continued to extrude from the summit, producing incandescence, strong gas-and-steam activity, and hot avalanches on the W and E flanks. Cloud-free satellite images detected a thermal anomaly over the volcano. The Aviation Color Code remained at Orange. KVERT reported that during 12-19 April moderate seismic activity continued at Kizimen. Video and satellite data showed that lava continued to extrude from the summit, producing incandescence, strong gas-and-steam activity, and hot avalanches on the W and E flanks. Satellite images detected a daily thermal anomaly over the volcano. The Aviation Color Code remained at Orange. KVERT reported that during 5-12 April moderate seismic activity continued at Kizimen. Video and satellite data showed that lava continued to extrude from the summit, producing incandescence, strong gas-and-steam activity, and hot avalanches on the W and E flanks. Satellite images detected a daily thermal anomaly over the volcano. The Aviation Color Code remained at orange. 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. RUSSIA - Grozny group - Kurile islands April 5th, 2013 SVERT reported that on 3 April at 0755 ash from Grozny Group fell in
Kurilsk (23 km N) and Kitovy, producing deposits 2-3 mm thick. Cloud cover
prevented observations of the volcano. The next day satellite images showed
an ash plume that rose 3 km (10,000 ft) a.s.l. and drifted W and NW. The
Aviation Color Code remained at Yellow. Based on analysis of satellite images, the Tokyo VAAC reported that on 30
March a possible eruption from Grozny Group may have produced a plume that
rose 2.1 km (7,000 ft) a.s.l. and drifted E. A later VAAC notice stated
that ash had dissipated.
The Grozny volcano group in central Iturup Island
contains the complex volcanoes of Ivan Grozny and Tebenkov. The former has
a 3-3.5 km diameter caldera that is open to the south, where the large,
1158-m-high andesitic Grozny extrusion dome (also known as
Etorofu-Yake-yama) was emplaced. Several other lava domes of Holocene age
were constructed to the NE; extrusion of these domes has constricted a
former lake in the northern side of the caldera to an extremely sinuous
shoreline. The forested andesitic Tebenkov volcano, also known as
Odamoi-san, lies immediately to the NE of the Grozny dome complex. The
large Machekh crater, which displays strong fumarolic activity, lies
immediately south of Tebenkov. Historical eruptions, the first of which
took place in 1968, have been restricted to Ivan Grozny. (GVN/GVP) January 9th, 2013 According to KVERT, observers on both Paramushir (SE) and Shumshu islands reported weak gas-and-steam plumes containing small amounts of ash from Alaid during 5, 11, 16-17, 23, and 27-28 October 2012. Photos taken on 27 October showed ash deposits on the cone and a small cinder cone growing in the crater. The cone was again covered by ash on 8 November. Seismicity increased on 16 November and remained elevated until 6 December, when it decreased until 10 December. Technical problems prevented seismic recordings after that. Satellite imagery showed a weak thermal anomaly on the volcano until 12 December. On 8 January 2013 the Aviation Color Code was lowered to Green. According to KVERT, observers on Paramushir Island (SE) reported weak gas-and-steam activity from Alaid during 11 and 16-17 October. A thermal anomaly on the volcano was detected in satellite imagery during 12 and 14-17 October. Cloud cover prevented observations during 19-22 October. Observers on Shumshu Island (50 km E) reported that an ash plume rose 700 m above the crater on 23 October and a thermal anomaly was detected in satellite imagery. The Aviation Color Code remained at Yellow. According to KVERT, observers on Paramushir Island reported that on 5 October a large gas-and-steam plume from Alaid rose 200 m above the crater. A thermal anomaly on the volcano was detected in satellite imagery for 7.5 hours the next day. The increased activity prompted KVERT to raise the Aviation Color Code to Yellow on 7 October. Satellite imagery detected a thermal anomaly on 15 October. The highest and northernmost volcano of the Kurile Islands, 2,339-m-high Alaid is a symmetrical stratovolcano when viewed from the N, but has a 1.5-km-wide summit crater that is breached widely to the S. Alaid is the northernmost of a chain of volcanoes constructed W of the main Kuril archipelago and rises 3,000 m from the floor of the Sea of Okhotsk. Numerous pyroclastic cones dot the lower flanks of Alaid, particularly on the NW and SE sides, including an offshore cone formed during the 1933-34 eruption. Strong explosive eruptions have occurred from the summit crater beginning in the 18th century. Reports of eruptions in 1770, 1789, 1821, 1829, 1843, 1848, and 1858 were considered incorrect by Gorshkov (1970). Explosive eruptions in 1790 and 1981 were among the largest in the Kurile Islands (gvn/gvp) article about Kurils Islands RUSSIA - Chirpoi volcano (Kurile islands) April 30th, 2013 SVERT reported that a weak thermal anomaly over Snow, a volcano of Chirpoi, was detected in satellite images on 24 and 26 April. SVERT reported that a weak thermal anomaly over Snow, a volcano of Chirpoi, was detected in satellite images during 12-13 April; cloud cover prevented observations of the volcano on other days during 8-15 April . SVERT reported that a weak thermal anomaly over Snow, a volcano of Chirpoi, was detected in satellite images on 6 April; cloud cover prevented observations of the volcano on other days during 1-8 April. SVERT reported that a weak thermal anomaly over Snow, a volcano of Chirpoi, was detected in satellite images on 14 March; cloud cover prevented observations of the volcano on other days during 11-18 March. SVERT reported that steam-and-gas emissions from Snow, a volcano of Chirpoi, were detected in satellite images on 5 March; cloud cover prevented observations of the volcano on other days during 4-11 March. SVERT reported that weak steam-and-gas emissions from Snow, a volcano of Chirpoi, were observed on 25 February, and 1 and 3 March. A thermal anomaly was detected in satellite images on 28 February and 3 March. Cloud cover prevented observations of the volcano on other days during 25 February-4 March. The Aviation Color Code was Yellow. SVERT reported that a thermal anomaly and weak steam-and-gas emissions from Snow, a volcano of Chirpoi, were detected in satellite images during 19 and 22-23 February; cloud cover prevented observations of the volcano on other days during 18-25 February. The Aviation Color Code was Yellow. SVERT reported that a thermal anomaly and weak steam-and-gas emissions from Snow, a volcano of Chirpoi, were detected in satellite images during 14-15 February; cloud cover prevented observations of the volcano on other days during 11-18 February. The Aviation Color Code was Yellow. SVERT reported that a thermal anomaly and steam-and-gas emissions from Snow, a volcano of Chirpoi, were detected in satellite images on 7 and 10 February; cloud cover prevented observations of the volcano on other days during 4-11 February. SVERT reported that steam-and-gas emissions from Snow, a volcano of Chirpoi, were detected in satellite images on 1 February; cloud cover prevented observations of the volcano on other days during 28 January-4 February. Chirpoi, a small island lying between the larger islands of Simushir and Urup, contains a half dozen volcanic edifices constructed within an 8-9 km wide, partially submerged caldera. The southern rim of the caldera is exposed on nearby Brat Chirpoev Island. Two volcanoes on Chirpoi Island have been historically active. The symmetrical Cherny volcano, which forms the 691 m high point of the island, erupted twice during the 18th and 19th centuries. The youngest volcano, Snow, originated between 1770 and 1810. It is composed almost entirely of lava flows, many of which have reached the sea on the southern coast. No historical eruptions are known from 742-m-high Brat Chirpoev, but its youthful morphology suggests recent strombolian activity. (GVN/GVP) *************************************************************************************************************************** NEW ZEALAND - Tongariro volcano March 30th, 2013 On 25 March GeoNet reported that Tongariro remained quiet with no eruptive
activity being detected since the explosion on 21 November 2012.
Steam-and-gas plumes rose from the Te Maari Craters. The Aviation Colour NEW ZEALAND - White island volcano May 2nd, 2013 On 29 April GeoNet Data Centre reported that activity at White Island
remained at a persistently low level, characterized by tremor and
degassing. No mud or ash eruptions had been observed since early April. A NEW ZEALAND - Havre seamount - Kermadec islands October 2nd, 2012 The GeoNet Data Centre reported that on 1 October a pilot observed floating
pumice in the Kermadec Islands NE of New Zealand. The area of pumice
started about 300 km W of Raoul Island and extended in a NE direction for
about 600 km. The report speculated that the pumice was from the 18-19 July
eruption of Havre Seamount and noted that there was no evidence that the
volcano had erupted again. previously, as of the 9th of August. local news reported that a large pumice raft was spotted North of the New Zealand coast. This pumice raft is probably the product of a submarine volcanic eruption from one of the multiple of seamounts that are part of Kermadec arc north of New Zealand. Exactly which volcano is the source of the pumice is unclear yet - First, it was suggested that Monowai was the source, but that seems to be in some question based on the location of the 26,000 km2 pumice raft.
According to Institute of Geological & Nuclear Sciences Limited (GNS) in a
media release on 11 August, the Laboratoire de Géophysique (Papeete,
Tahiti) described the source of a pumice raft in the Kermadec Islands. They
noted that a short seismic swarm with hydro-acoustic and seismic phases was
recorded by the Polynesian Network during 17-18 July. More than 157 events
were detected, at magnitudes between 3 and 4.8. The large pumice raft was
first observed on 19 July, W and S of Raoul Island, then reported for
several more days. Analysis of satellite imagery indicated that the source
of the pumice raft was at 30.95 S and 179.13 W, 72 km SW of Curtis Island.
A scientist aboard the HMNZS Canterbury described the pumice raft as 0.6 m
thick, 1 km wide, and extended to the right and left as far as the eye
could see. According to a news article, a pilot of an Air Force Orion
aircraft reported on 9 August that the raft was 463 km by 55 km, or
covering an area of approximately 25,000 square kilometers.
Scientists analyzing satellite imagery and sea floor bathymetry suggested
that the eruption originated from the Havre Seamount. The earliest evidence
of the eruption was detected in thermal imagery at 2250 on 18 July. March 13th, 2013 On 12 March, GeoNet reported that the Volcanic Alert Level for Ruapehu remained at 1 (signs of volcano unrest) and the Aviation Colour Code was lowered to Green based on the analysis of monitoring data and the lack of recent seismic activity. On 5 March, GeoNet reported that monitoring of the Ruapehu Crater Lake showed that temperatures at depth remained above background levels but had started a declining trend. Gas data from January and February showed emission rates of 15-25 tonnes per day of sulfur dioxide and around 650 tonnes per day carbon dioxide; these are within the usual range of emissions measured at Ruapehu. Seismicity remained low, characterized by weak volcanic tremor and some shallow earthquakes. Areas of discoloration in the lake, sometimes observed during the previous few weeks, are relatively common and thought to reflect internal lake convection processes. Scientists speculated that there was a partial blockage between the deep and shallow systems causing the lake temperature to remain steady; the relatively low temperature of Crater Lake, 22-25°C since March 2012, is one of the longest periods of low lake temperatures recorded. The Volcanic Alert Level remained at 1 (signs of volcano unrest) and the Aviation Colour Code remained at Yellow. 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 ********************************************************************************************************* PAPUA - NEW GUINEA - Manam volcano May 18th, 2013 RVO reported that during 29 April-16 May activity at Manam was low,
characterized by white, and sometimes blue, vapor plumes rising from
Southern Crater. White vapor plumes also rose from Main Crater. Seismicity February 28th, 2013
Based on analyses of satellite imagery and wind data, the Darwin VAAC
reported that on 26 February an ash plume from Karkar rose to an altitude
of 8.5 km (28,000 ft) a.s.l. and drifted 75 km N and 130 km E.
Karkar volcano is a 19 x 25 km wide, forest-covered island that
is truncated by two nested summit calderas. The 5.5-km-wide outer caldera
was formed during one or more eruptions, the last of which occurred 9000
years ago. The eccentric 3.2-km-wide inner caldera was formed sometime
between 1500 and 800 years ago. Parasitic cones are present on the northern
and southern flanks of basaltic-to-andesitic Karkar volcano; a linear array
of small cones extends from the northern rim of the outer caldera nearly to
the coast. Most historical eruptions, which date back to 1643, have
originated from Bagiai cone, a pyroclastic cone constructed within the
steep-walled, 300-m-deep inner caldera. The floor of the caldera is covered
by young, mostly unvegetated andesitic lava flows. (GVN/GVP) May 18th, 2013 RVO reported that during 29 April-16 May white vapor plumes sometimes
containing fine ash rose at most 200 m from Rabaul caldera's Tavurvur cone
and drifted NW. Ashfall was reported in areas downwind including Rabaul
town (3-5 km NW). Roaring and rumbling noises also continued. Seismicity
was low. RVO reported that during 24-28 April white vapor plumes sometimes
containing ash rose at most 200 m from Rabaul caldera's Tavurvur cone and
drifted SE. Roaring and rumbling noises also continued but the intensity PAPUA - NEW GUINEA - Bagana volcano (Bougainville island) May 7th, 2013 Based on analyses of satellite imagery and wind data, the Darwin VAAC reported that during 5-6 May ash plumes from Bagana rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted 75-85 km W.Based on analyses of satellite imagery and wind data, the Darwin VAAC reported that during 10-11 April ash plumes from Bagana rose to an altitude of 2.4 km (8,000 ft) a.s.l. and drifted 75 km SW and W. On 15 April an ash plume rose to an altitude of 1.8 km (6,000 ft) a.s.l. and drifted almost 30 km S and W. The next day ash plumes rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted 65 km SW. Based on analyses of satellite imagery and wind data, the Darwin VAAC reported that on 7 April ash plumes from Bagana rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted almost 85 km SW and WSW. On 9 April an ash plume rose to an altitude of 4 km (13,000 ft) a.s.l. and drifted almost 75 km SW. Based on analyses of satellite imagery and wind data, the Darwin VAAC reported that during 25-26 March ash plumes from Bagana rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted 45-55 km E. Based on analyses of satellite imagery and wind data, the Darwin VAAC reported that during 12-14 February ash plumes from Bagana rose to an altitude of 1.5 km (5,000 ft) a.s.l. and drifted 35-55 km SW and NW. Based on analyses of satellite imagery and wind data, the Darwin VAAC reported that during 8-12 February ash plumes from Bagana rose to altitudes of 1.5-3 km (5,000-10,000 ft) a.s.l. and drifted 35-130 km E and NW. Bagana volcano, occupying a remote portion of central Bougainville Island, is one of Melanesia's youngest and most active volcanoes. Bagana is a massive symmetrical lava cone largely constructed by an accumulation of viscous andesitic lava flows. The entire lava cone could have been constructed in about 300 years at its present rate of lava production. Eruptive activity at Bagana is characterized by non-explosive effusion of viscous lava that maintains a small lava dome in the summit crater, although explosive activity occasionally producing pyroclastic flows also occurs. Lava flows form dramatic, freshly preserved tongue-shaped lobes up to 50-m-thick with prominent levees that descend the volcano's flanks on all sides. (GVN/GVP Papua-New Guinea - Ulawun volcano (New britain) December 18th, 2012 RVO reported that dense gray-brown ash plumes that began rising from Ulawun
on 6 November ceased on 11 December. During 12-16 December variable amounts
of white vapor plumes rose from the crater. SANTA CRUZ ISLAND - Tinakula volcano February 22nd, 2012
According to NASA's Earth Observatory, thermal anomalies from Tinakula were
detected in satellite data during 13-14 February and a gas plume with
possible ash content rose from the volcano on 14 February. Mariannes islands - Pagan volcano February 18th , 2013 Satellite imagery showed a plume of gas and water vapor drifting 240 km downwind from Pagan daily during 9-15 February. A USGS team that visited Pagan on 9 February observed a continuous, vigorous plume and noted a sulfur odor downwind of the summit. Previous year news :Satellite imagery showed a plume drifting from Pagan during 1-7 December 2012. On 29 November observers in Saipan reported hazy sky conditions associated with N winds that pushed the gas-and-vapor plume from Pagan S. Since then, no additional reports of haze or vog associated with the Pagan plume were noted. Clear satellite views showed steam-and-gas emissions drifting from Pagan during 17-24 November. According to the Washington VAAC, ash from an unknown volcano was reported by a pilot in the vicinity of Pagan on 25 November. Satellite imagery suggested continuing degassing, but it was possible that ash was present in a 30-km-wide plume that was drifting almost 90 km S. Mostly gas was seen drifting S in an image later that day.Continuous steam-and-gas plumes from Pagan were observed in clear satellite images during 12-19 October. According to NASA's Earth Observatory, a satellite image acquired on 16 October showed a steam-and-gas plume drifting WNW. The Aviation Color Code remained at Yellow and the Volcano Alert Level remained at Advisory. 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. *************************************************************************************************************************** INDIAN OCEAN SOUTH - Heard island volcano April 25th, 2013 According to NASA Earth Observatory (EO) an image acquired on 7 April 2013 from
the Advanced Land Imager (ALI) on NASA's EO-1 satellite showed that
Mawson's Peak crater on Heard Island had filled and a lava flow had
traveled down the SW flank. The lava flow was visible in an image acquired
on 20 April and had slightly widened just below the summit. Heard Island on the Kerguelen Plateau in the southern
Indian Ocean consists primarily of the emergent portion of two volcanic
structures. The large glacier-covered composite basaltic-to-trachytic cone
of Big Ben comprises most of the island, and the smaller Mt. Dixon volcano
lies at the NW tip of the island across a narrow isthmus. Little is known
about the structure of Big Ben volcano because of its extensive ice cover.
The historically active Mawson Peak forms the island's 2745-m high point
and lies within a 5-6 km wide caldera breached to the SW side of Big Ben.
Small satellitic scoria cones are mostly located on the northern coast.
Several subglacial eruptions have been reported in historical time at this
isolated volcano, but observations are infrequent and additional activity
may have occurred.(Smithsonian Scientific Event Alert Network
Bulletin). March 1st, 2012 As of the 1st of March 2012, 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. Previous special news : 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 ************************************************************************************************************ Vanuatu - Aoba volcano (Ambae) March 8th, 2013 According to observations by the Vanuatu Meteorology and Geohazards
Department, a report from 6 March stated that the minor activity at Aoba
that began in December 2012 was likely continuing. Satellite images 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 |
Bezymianny volcano - H. Gaudru 1992 |
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VANUATU - Yasur volcano ( Tanna island) April 7th, 2013 According to observations by the Vanuatu Meteorology and Geohazards department, started from 02nd April 2013, the explosive activity level of Yasur volcano has slightly increased. Explosions have become slightly stronger and more frequent. The fresh volcanic bombs from active vents have been falling around the summit area, the tourist walk and the parking area. Yasur volcano exhibited ash venting beginning on 02nd April 2013 and believed to continue. With this situation, villages and communities located far away and close to the volcano, especially those in the prevailing trade winds direction will expect ash falls (See Fig.2a/b). The Volcanic Alert Level of Yasur volcano increase at Level 2, the risk remains near the volcano crater for volcanic projections, and in part of the Red Zone for volcanic ash falls. This level of alert could evolve in the coming days. Moderate ash venting occurred at Yasur volcano at 15:15 pm (02 April), at 09:30 am (4 April) and at 07:00am (5 April). Satellite image (OMI) on 01st April 2013 shows the light degassing from Yasur volcano Previously, past year, following an assessment during 7-12 July 2012, the Geohazards Observatory team concluded that explosive activity at Yasur had slightly increased, becoming stronger and more frequent, and shifting from Strombolian to sub-Plinian. Bombs ejected from the vents fell in the crater, around the summit area, and on the tourist walk and parking area. The explosions were heard, felt, and observed from nearby villages and schools. Activity at all three volcanic vents was characterized by degassing, ash emissions, and ejection of bombs. On 13 July the Alert Level was raised to 3 (on a scale of 0-4). Previously, On 13 June 2011, 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) VANUATU - SVE Travel volcanic fieldtrip in project for 2013 (SEPTEMBER ?) - if you are interested please contact us : info@sveurop.org
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