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Smithsonian/USGS Weekly Volcanic Activity Report 19-25 March 2014
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Smithsonian/USGS Weekly Volcanic Activity Report
19-25 March 2014
Sally Kuhn Sennert - Weekly Report Editor kuhns@si.edu
URL: http://www.volcano.si.edu/reports/usgs/
New Activity/Unrest: | Copahue, Central Chile-Argentina | Fuego, Guatemala | Ubinas, Perú
Ongoing Activity: | Aira, Kyushu | Bagana, Bougainville | Batu Tara, Komba Island (Indonesia) | Chirinkotan, Kuril Islands | Chirpoi, Kuril Islands (Russia) | Colima, México border | Dukono, Halmahera | Etna, Sicily (Italy) | Karymsky, Eastern Kamchatka (Russia) | Kilauea, Hawaii (USA) | Rabaul, New Britain | Shishaldin, Fox Islands | Shiveluch, Central Kamchatka (Russia) | Sinabung, Sumatra (Indonesia) | Tungurahua, Ecuador
The Weekly Volcanic Activity Report is a cooperative project between the Smithsonian's Global Volcanism Program and the US Geological Survey's Volcano Hazards Program. Updated by 2300 UTC every Wednesday, notices of volcanic activity posted on these pages are preliminary and subject to change as events are studied in more detail. This is not a comprehensive list of all of Earth's volcanoes erupting during the week, but rather a summary of activity at volcanoes that meet criteria discussed in detail in the "Criteria and Disclaimers" section. Carefully reviewed, detailed reports on various volcanoes are published monthly in the Bulletin of the Global Volcanism Network.
Note: Many news agencies do not archive the articles they post on the Internet, and therefore the links to some sources may not be active. To obtain information about the cited articles that are no longer available on the Internet contact the source.
New Activity/Unrest
COPAHUE Central Chile-Argentina border 37.85°S, 71.17°W; summit elev. 2997 m
OVDAS-SERNAGEOMIN reported that a gradual increase of volcanic tremor was detected at Copahue starting at 0230 on 20 March; from 0230 to 1100 the signal fluctuated and intense periods lasted up to 3 hours. Cameras showed minimal activity at the surface while concentrations of sulfur dioxide increased. The Alert Level was raised to Orange. Residents and visitors were prohibited within a 3-km radius of the active crater. During 21-24 March gas plumes rose at most 500 m and drifted E. Seismicity continued to increase.
Geologic Summary. 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.
Source: Servicio Nacional de Geología y Minería (SERNAGEOMIN) http://www.sernageomin.cl/
FUEGO Guatemala 14.473°N, 90.880°W; summit elev. 3763 m
INSIVUMEH reported that during 20-21 March explosions at Fuego produced ash plumes that rose 500-800 m above the crater and drifted 9-10 km W. Incandescent material was ejected 200 m high. Later on 21 March seismicity increased. The number of explosions also increased to 7-9 moderate to strong explosions per hour. Ash plumes rose 750-950 m and drifted 15 km WSW. Shock waves vibrated structures in areas 8 km away, including Santa Sofía (12 km SW), Panimaché (8 km SW), and Morelia (9 km SW). During 22-23 March explosions generated ash plumes that rose 500-800 m and drifted 10-12 km S and SW. Incandescent material was ejected 200 m high. Ashfall was reported in Santa Sofía, Panimaché, Panimaché II (8 km SW), and Morelia. On 25 March INSIVUMEH noted that activity remained high; 8-14 explosions per hour generated ash plumes that rose 850-1,050 m and drifted 12 km W and SW. Ashfall was reported in Sangre de Cristo (8 km WSW) and surrounding areas. Explosions again vibrated structures in Santa Sofía, Panimaché, Panimaché II, and Morelia.
Geologic Summary. Volcán Fuego, one of Central America's most active volcanoes, is one of three large stratovolcanoes overlooking Guatemala's former capital, Antigua. The scarp of an older edifice, Meseta, lies between 3,763-m-high Fuego and its twin volcano to the N, Acatenango. Construction of Meseta volcano continued until the late Pleistocene or early Holocene, after which growth of the modern Fuego volcano continued the southward migration of volcanism that began at Acatenango. Frequent vigorous historical eruptions have been recorded at Fuego since the onset of the Spanish era in 1524, and have produced major ashfalls, along with occasional pyroclastic flows and lava flows. The last major explosive eruption from Fuego took place in 1974, producing spectacular pyroclastic flows visible from Antigua.
Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH) http://www.insivumeh.gob.gt/
UBINAS Perú 16.355°S, 70.903°W; summit elev. 5672 m
In a 23 March news article IGP volcanologists noted that the seismic network at Ubinas indicated a large output of lava during 10-11 March; sulfur dioxide emissions also increased during this period. Lava in the crater was incandescent. Based on analysis of satellite images and the INGEMMET web cam, the Buenos Aires VAAC reported that an emission of gas and steam on 23 March possibly contained diffuse ash. The plume drifted NE before dissipating about 55 km away. The next day another steam-and-gas emission possibly containing some ash drifted NE.
On 25 March Observatorio Vulcanológico del INGEMMET (OVI) reported that in the previous days bluish white gas plumes rose 1.3 km above the crater rim and sulfur dioxide emissions averaged 2,200 tons per day. The report also noted that lava had continued to erupt in recent weeks.
Geologic Summary. A small, 1.2-km-wide caldera that cuts the top of Ubinas, Peru's most active volcano, gives it a truncated appearance. Ubinas is the northernmost of three young volcanoes located along a regional structural lineament about 50 km behind the main volcanic front of Peru. The upper slopes of the stratovolcano, composed primarily of Pleistocene andesitic lava flows, steepen to nearly 45 degrees. The steep-walled, 150-m-deep summit caldera contains an ash cone with a 500-m-wide funnel-shaped vent that is 200 m deep. Debris-avalanche deposits from the collapse of the SE flank of Ubinas extend 10 km from the volcano. Widespread Plinian pumice-fall deposits from Ubinas include some of Holocene age. Holocene lava flows are visible on the volcano's flanks, but historical activity, documented since the 16th century, has consisted of intermittent minor explosive eruptions.
Sources: Instituto Geológico Minero y Metalúrgico (INGEMMET) http://www.ingemmet.gob.pe/form/Inicio.aspx,
Grupo RPP http://www.rpp.com.pe/2014-03-23-arequipa-revelan-que-magma-se-incrementa-en-crater-del-vo lcan-ubinas-noticia_678859.html,
Buenos Aires Volcanic Ash Advisory Center (VAAC) http://www.smn.gov.ar/vaac/buenosaires/productos.php
Ongoing Activity
AIRA Kyushu 31.585°N, 130.657°E; summit elev. 1117 m
JMA reported that during 17-20 March five explosions from Showa Crater at Aira Caldera's Sakurajima volcano ejected tephra as far as 1,300 m. Incandescence from the crater was detected at night during 17-18 March. The Alert Level remained at 3 (on a scale of 1-5). The Tokyo VAAC reported that during 20-25 March plumes rose to altitudes of 1.2-2.7 km (4,000-9,000 ft) a.s.l. and drifted SE, SW, N, and NE.
Geologic Summary. The Aira caldera in the northern half of Kagoshima Bay contains the post-caldera Sakurajima volcano, one of Japan's most active. Eruption of the voluminous Ito pyroclastic flow accompanied formation of the 17 x 23 km caldera about 22,000 years ago. The smaller Wakamiko caldera was formed during the early Holocene in the NE corner of the Aira caldera, along with several post-caldera cones. The construction of Sakurajima began about 13,000 years ago on the southern rim of Aira caldera and built an island that was finally joined to the Osumi Peninsula during the major explosive and effusive eruption of 1914. Activity at the Kitadake summit cone ended about 4850 years ago, after which eruptions took place at Minamidake. Frequent historical eruptions, recorded since the 8th century, have deposited ash on Kagoshima, one of Kyushu's largest cities, located across Kagoshima Bay only 8 km from the summit. The largest historical eruption took place during 1471-76.
Sources: Japan Meteorological Agency (JMA) http://www.jma.go.jp/jma/index.html,
Tokyo Volcanic Ash Advisory Center (VAAC) http://ds.data.jma.go.jp/svd/vaac/data/vaac_list.html
BAGANA Bougainville 6.140°S, 155.195°E; summit elev. 1750 m
Based on analyses of satellite imagery and wind data, the Darwin VAAC reported that on 22 March an ash plume from Bagana rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted 110 km NE.
Geologic Summary. 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.
Source: Darwin Volcanic Ash Advisory Centre (VAAC) http://www.ssd.noaa.gov/VAAC/OTH/AU/messages.html
BATU TARA Komba Island (Indonesia) 7.792°S, 123.579°E; summit elev. 748 m
Based on analyses of satellite imagery and wind data, the Darwin VAAC reported that on 22 March an ash plume from Batu Tara drifted almost 20 km W.
Geologic Summary. The small isolated island of Batu Tara in the Flores Sea about 50 km north of Lembata (formerly Lomblen) Island contains a scarp on the eastern side similar to the Sciara del Fuoco of Italy's Stromboli volcano. Vegetation covers the flanks of Batu Tara to within 50 m of the 748-m-high summit. Batu Tara lies north of the main volcanic arc and is noted for its potassic leucite-bearing basanitic and tephritic rocks. The first historical eruption from Batu Tara, during 1847-52, produced explosions and a lava flow.
Source: Darwin Volcanic Ash Advisory Centre (VAAC) ftp://ftp.bom.gov.au/anon/gen/vaac/
CHIRINKOTAN Kuril Islands 48.980°N, 153.480°E; summit elev. 724 m
SVERT reported that a steam-and-gas plume from Chirinkotan was observed in satellite images drifting more than 80 km SE on 20 March. Diffuse steam-and-gas emissions were observed during 21-22 March. Cloud cover obscured views on the other days during 17-19 and 23-24 March. The Aviation Color Code remained at Yellow.
Geologic Summary. The small, mostly unvegetated 3-km-wide island of Chirinkotan occupies the far end of an E-W-trending volcanic chain that extends nearly 50 km west of the central part of the main Kuril Islands arc. Chirinkotan is the emergent summit of a volcano that rises 3000 m from the floor of the Kuril Basin. A small 1-km-wide caldera about 300-400 m deep is open to the SE. Lava flows from a cone within the breached crater reached the north shore of the island. Historical eruptions have been recorded at Chirinkotan since the 18th century. Fresh lava flows also descended the SE flank of Chirinkotan during an eruption in the 1880s that was observed by the English fur trader Captain Snow.
Source: Sakhalin Volcanic Eruption Response Team (SVERT) http://www.imgg.ru/?id_d=659
CHIRPOI Kuril Islands (Russia) 46.525°N, 150.875°E; summit elev. 742 m
SVERT reported that a steam-and-gas plume from Snow, a volcano of Chirpoi, was detected in satellite images drifting 150 km SE on 20 March. Cloud cover obscured views during 17-19 and 21-24 March. The Aviation Color Code remained at Yellow.
Geologic Summary. 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.
Source: Sakhalin Volcanic Eruption Response Team (SVERT) http://www.imgg.ru/en/home.html
COLIMA México 19.514°N, 103.62°W; summit elev. 3850 m
Based on observations of satellite images, the Washington VAAC reported that on 19 March small diffuse puffs rose from Colima to an altitude of 4.6 km (15,000 ft) a.s.l., drifted E, and dissipated almost 30 km away. A diffuse ash plume drifted N on 22 March.
Geologic Summary. The Colima volcanic complex is the most prominent volcanic center of the western Mexican Volcanic Belt. It consists of two southward-younging volcanoes, Nevado de Colima (the 4,320 m high point of the complex) on the N and the historically active Volcán de Colima on the S. Volcán de Colima (also known as Volcán Fuego) is a youthful stratovolcano constructed within a 5-km-wide caldera, breached to the S, that has been the source of large debris avalanches. Major slope failures have occurred repeatedly from both the Nevado and Colima cones, and have produced a thick apron of debris-avalanche deposits on three sides of the complex. 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.
Source: Washington Volcanic Ash Advisory Center (VAAC) http://www.ssd.noaa.gov/VAAC/messages.html
DUKONO Halmahera 1.68°N, 127.88°E; summit elev. 1335 m
Based on analyses of satellite imagery and wind data, the Darwin VAAC reported that during 20-25 March ash plumes from Dukono rose to altitudes of 2.4-2.7 km (8,000-9,000 ft) a.s.l. and drifted 45-100 km SE, E, and NE.
Geologic Summary. 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. During a major eruption in 1550, a lava flow filled in the strait between Halmahera and the N-flank cone of Gunung Mamuya. Dukono is a complex volcano presenting a broad, low profile with multiple summit peaks and overlapping craters. Malupang Wariang, 1 km SW of Dukono's summit crater complex, contains a 700 x 570 m crater that has also been active during historical time.
Source: Darwin Volcanic Ash Advisory Centre (VAAC) ftp://ftp.bom.gov.au/anon/gen/vaac/
ETNA Sicily (Italy) 37.734°N, 15.004°E; summit elev. 3330 m
INGV reported on 24 March that during the previous week Strombolian activity with occasional diffuse ash emissions continued from one or two vents at the base of Etna's New Southeast Crater (NSEC) cone. Strombolian activity intensified during 18-22 March, producing more ash, and then decreased; no ash was emitted on 23 March. Lava flows originating from a vent on the upper wall traveled towards the upper part of the W wall of the Valle del Bove and also NE in the direction of Monte Simone.
Geologic Summary. Mount Etna, towering above Catania, Sicily's second largest city, has one of the world's longest documented records of historical volcanism, dating back to 1500 BC. Historical lava flows cover much of the surface of this massive basaltic stratovolcano, the highest and most voluminous in Italy. Two styles of eruptive activity typically occur at Etna. Persistent explosive eruptions, sometimes with minor lava emissions, take place from one or more of the three prominent summit craters, the Central Crater, NE Crater, and SE Crater. Flank eruptions, typically with higher effusion rates, occur less frequently and originate from fissures that open progressively downward from near the summit. A period of more intense intermittent explosive eruptions from Etna's summit craters began in 1995. The active volcano is monitored by the Instituto Nazionale di Geofisica e Volcanologia (INGV) in Catania.
Source: Sezione di Catania - Osservatorio Etneo (INGV) http://www.ct.ingv.it/
KARYMSKY Eastern Kamchatka (Russia) 54.05°N, 159.45°E; summit elev. 1536 m
KVERT reported that Vulcanian and Strombolian activity at Karymsky continued during 14-21 March. Satellite images detected a bright thermal anomaly on the volcano daily. Ash plumes rose to altitudes of 1.5-2 km (3,300-6,600 ft) a.s.l. and drifted 70-150 km SE during 16-18 and 21 March. The Aviation Color Code remained at Orange.
Geologic Summary. Karymsky, the most active volcano of Kamchatka's eastern volcanic zone, is a symmetrical stratovolcano constructed within a 5-km-wide caldera that formed about 7,600-7,700 radiocarbon years ago. Construction of the Karymsky stratovolcano began about 2,000 years later. The latest eruptive period began about 500 years ago, following a 2,300-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. Most seismicity preceding Karymsky eruptions has originated beneath Akademia Nauk caldera, which is located immediately S of Karymsky volcano and erupted simultaneously with Karymsky in 1996.
Source: Kamchatkan Volcanic Eruption Response Team (KVERT) http://www.kscnet.ru/ivs/kvert/index_eng.php
KILAUEA Hawaii (USA) 19.421°N, 155.287°W; summit elev. 1222 m
During 19-25 March HVO reported that the circulating lava lake occasionally rose and fell in the deep pit within Kilauea's Halema'uma'u Crater. Gas emissions remained elevated. The plume from the vent continued to deposit variable amounts of ash, spatter, and Pele's hair onto nearby areas; smaller particles may have been dropped several kilometers away. At Pu'u 'O'o Crater, glow emanated from spatter cones on the N and S portions of the crater floor, and from the lava pond in the NE spatter cone. Lava from the pond periodically spilled over the rim during 18-19 March. Breakouts from the main stalled lobe of the Kahauale'a 2 lava flow, fed by the NE spatter cone, continued to advance and burn adjoining forest. Overflight mapping on 21 March showed that the edge of the most distant breakout flow was 8.2 km NE of Pu'u 'O'o.
Geologic Summary. Kilauea, one of five coalescing volcanoes that comprise the island of Hawaii, is one of the world's most active volcanoes. Eruptions at Kilauea originate primarily from the summit caldera or along one of the lengthy E and SW rift zones that extend from the caldera to the sea. About 90% of the surface of Kilauea is formed of lava flows less than about 1,100 years old; 70% of the volcano's surface is younger than 600 years. A long-term eruption from the East rift zone that began in 1983 has produced lava flows covering more than 100 sq km, destroying nearly 200 houses and adding new coastline to the island.
Source: US Geological Survey Hawaiian Volcano Observatory (HVO) http://hvo.wr.usgs.gov/
RABAUL New Britain 4.271°S, 152.203°E; summit elev. 688 m
RVO reported that explosions from Rabaul caldera's Tavurvur cone were detected during 1-11 March, notably during 1 and 6-11 March, and generated ash plumes that rose 1 km and drifted E and SE. Mild ash emissions on other days during 1-15 March also drifted E and SE. Gases from Tavurvur caused browning vegetation on Turangunan (South Daughter) since early January.
Geologic Summary. The low-lying Rabaul caldera on the tip of the Gazelle Peninsula at the NE end of New Britain forms a broad sheltered harbor. The outer flanks of the 688-m-high asymmetrical pyroclastic shield volcano are formed by thick pyroclastic-flow deposits. The 8 x 14 km caldera is widely breached on the E, where its floor is flooded by Blanche Bay. Two major Holocene caldera-forming eruptions at Rabaul took place as recently as 3,500 and 1,400 years ago. Three small stratovolcanoes lie outside the northern and NE caldera rims. Post-caldera eruptions built basaltic-to-dacitic pyroclastic cones on the caldera floor near the NE and western caldera walls. Several of these, including Vulcan cone, which was formed during a large eruption in 1878, have produced major explosive activity during historical time. A powerful explosive eruption in 1994 occurred simultaneously from Vulcan and Tavurvur volcanoes and forced the temporary abandonment of Rabaul city.
Source: Rabaul Volcano Observatory (RVO)
SHISHALDIN Fox Islands 54.756°N, 163.97°W; summit elev. 2857 m
AVO reported that ground-coupled air waves from small explosions at Shishaldin's summit area were detected in seismic data during 19-25 March. Elevated surface temperatures were identified on most days during this period. The Aviation Color Code remained at Yellow and the Volcano Alert Level remained at Advisory.
Geologic Summary. The beautifully symmetrical volcano of Shishaldin is the highest and one of the most active volcanoes of the Aleutian Islands. The 2,857-m-high, glacier-covered volcano is the westernmost of three large stratovolcanoes along an E-W line in the eastern half of Unimak Island. Constructed atop an older glacially dissected volcano, Shishaldin is Holocene in age and largely basaltic in composition. Remnants of an older ancestral volcano are exposed on the W and NE sides at 1,500-1,800 m elevation. Shishaldin contains over two dozen pyroclastic cones on its NW flank, which is blanketed by massive aa lava flows. Frequent explosive activity, primarily consisting of Strombolian ash eruptions from the small summit crater, sometimes producing lava flows, have been recorded since the 18th century.
Source: US Geological Survey Alaska Volcano Observatory (AVO) http://www.avo.alaska.edu/
SHIVELUCH Central Kamchatka (Russia) 56.653°N, 161.360°E; summit elev. 3283 m
KVERT reported that during 14-21 March lava-dome extrusion at Shiveluch was accompanied by ash explosions, incandescence, hot avalanches, and fumarolic activity. A bright thermal anomaly was detected daily in satellite images. The Aviation Color Code remained at Orange.
Geologic Summary. The high, isolated massif of Shiveluch volcano (also spelled Sheveluch) rises above the lowlands NNE of the Kliuchevskaya volcano group and forms one of Kamchatka's largest and most active volcanoes. The currently active Molodoy Shiveluch lava-dome complex was constructed during the Holocene within a large breached caldera formed by collapse of the massive late-Pleistocene Strary Shiveluch volcano. At least 60 large eruptions of Shiveluch have occurred during the Holocene, making it the most vigorous andesitic volcano of the Kuril-Kamchatka arc. Frequent collapses of lava-dome complexes, most recently in 1964, have produced large debris avalanches whose deposits cover much of the floor of the breached caldera. Intermittent explosive eruptions began in the 1990s from a new lava dome that began growing in 1980. The largest historical eruptions from Shiveluch occurred in 1854 and 1964.
Source: Kamchatkan Volcanic Eruption Response Team (KVERT) http://www.kscnet.ru/ivs/kvert/index_eng.php
SINABUNG Sumatra (Indonesia) 3.17°N, 98.392°E; summit elev. 2460 m
PVMBG described activity at Sinabung during 15-22 March based on observations from a post in the Ndokum Siroga village, 8.5 km away. Dense white plumes rose 500 m above the lava dome daily, and as high as 1 km on 21 March. Lava had traveled 2.4 km down the flanks as of 20 March and was incandescent at various areas. Incandescent material originating from the edges of the lava dome and flow traveled up to 1.5 km S and 200 m SE. A pyroclastic flow traveled 3 km S on 17 March. Tremor and volcanic earthquakes were detected, and signals representing avalanches from the unstable and still-growing dome decreased slightly. Sulfur dioxide emissions varied between 300 and 598 tons per day, indicating no new magma. The Alert Level remained at 4 (on a scale of 1-4). Visitors and tourists were prohibited from approaching the crater within a radius of 5 km.
Geologic Summary. Gunung Sinabung is a Pleistocene-to-Holocene stratovolcano with many lava flows on its flanks. The migration of summit vents along a N-S line gives the summit crater complex an elongated form. The youngest crater of this conical, 2460-m-high andesitic-to-dacitic volcano is at the southern end of the four overlapping summit craters. An unconfirmed eruption was noted in 1881, and solfataric activity was seen at the summit and upper flanks of Sinabung in 1912, although no confirmed historical eruptions were recorded prior to 2010.
Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) also known CVGHM http://www.vsi.esdm.go.id/
TUNGURAHUA Ecuador 1.467°S, 78.442°W; summit elev. 5023 m
IG reported that activity at Tungurahua was at moderate levels during 19-25 March; cloud cover often prevented observations. On 21 March an explosion was later followed by ashfall in Choglontus (SW). Heavy rains caused lahars in the Achupashal drainage (NW) which led to traffic disruption on the Baños- Penipe highway. Lahars also descended the Juive drainage (7 km NNW). On 25 March an ash plume rose 3 km and drifted N. Ashfall was reported in Quero (20 km NW) and Puñachiza.
Geologic Summary. The steep-sided Tungurahua stratovolcano towers more than 3 km above its northern base. It sits ~140 km S of Quito, Ecuador's capital city, and is one of Ecuador's most active volcanoes. Historical eruptions have all originated from the summit crater. They have been accompanied by strong explosions and sometimes by pyroclastic flows and lava flows that reached populated areas at the volcano's base. The last major eruption took place from 1916 to 1918, although minor activity continued until 1925. The latest eruption began in October 1999 and prompted temporary evacuation of the town of Baños on the N side of the volcano.
Source: Instituto Geofísico-Escuela Politécnica Nacional (IG) http://www.igepn.edu.ec/
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Sally Kuhn Sennert
SI/USGS Weekly Volcanic Activity Report Editor
Global Volcanism Program
http://www.volcano.si.edu/reports/usgs/
Smithsonian Institution, National Museum of Natural History
Department of Mineral Sciences, MRC-119
Washington, D.C., 20560
Phone: 202.633.1805
Fax: 202.357.2476
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