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Smithsonian/USGS Weekly Volcanic Activity Report 7-13 November 2012
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Smithsonian/USGS Weekly Volcanic Activity Report
7-13 November 2012
Sally Kuhn Sennert - Weekly Report Editor
URL: http://www.volcano.si.edu/reports/usgs/
New Activity/Unrest: | Cleveland, Chuginadak Island | Kizimen, Eastern Kamchatka (Russia) | Paluweh, Lesser Sunda Islands (Indonesia) | Reventador, Ecuador | Villarrica, Central Chile
Ongoing Activity: | Fuego, Guatemala | Karymsky, Eastern Kamchatka (Russia) | Kilauea, Hawaii (USA) | Lokon-Empung, Sulawesi | Ruapehu, North Island (New Zealand) | Sakura-jima, Kyushu | Shiveluch, Central Kamchatka (Russia) | Tongariro, North Island (New Zealand)
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
CLEVELAND Chuginadak Island 52.825°N, 169.944°W; summit elev. 1730 m
AVO reported that on 6 November thermal infrared satellite images of Cleveland showed elevated surface temperatures. Clouds obscure views of the lava dome during 7-9 November. A small ash cloud drifting ENE was detected in satellite imagery at 1147 on 10 November. The Volcano Alert Level was raised to Watch and the Aviation Color Code was raised to Orange. At 1843 the ash cloud was observed almost 100 km S of Dutch Harbor (260 km ENE). No new activity was observed in mostly cloudy images during11-13 November. Post-event analysis of infrasound data suggested that a small explosion likely occurred at 1125 on 10 November.
Geologic Summary. Symmetrical Mount Cleveland stratovolcano is situated at the western end of the uninhabited dumbbell-shaped Chuginadak Island in the east-central Aleutians. The 1,730-m-high stratovolcano is the highest of the Islands of Four Mountains group and is one of the most active in the Aleutians. Numerous large lava flows descend its flanks. It is possible that some 18th to 19th century eruptions attributed to Carlisle (a volcano located across the Carlisle Pass Strait to the NW) should be ascribed to Cleveland. 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.
Source: Alaska Volcano Observatory (AVO) http://www.avo.alaska.edu/
KIZIMEN Eastern Kamchatka (Russia) 55.130°N, 160.32°E; summit elev. 2376 m
KVERT reported that during 2-9 November moderate seismic activity at Kizimen was detected. Video and satellite images showed lava flows effusing from the summit and the E flank, summit incandescence, strong gas-and-steam activity, and hot avalanches on the S flank. During 1-2 and 6-7 November a thermal anomaly was detected in satellite images. The Aviation Color Code remained at Orange.
Geologic Summary. Kizimen is an isolated, conical stratovolcano that is morphologically similar to Mount St. Helens prior to its 1980 eruption. The summit of Kizimen consists of overlapping lava domes, and blocky lava flows descend the flanks of the volcano, which is the westernmost of a volcanic chain north of Kronotsky volcano. The 2,376-m-high Kizimen was formed during four eruptive cycles beginning about 12,000 years ago and lasting 2,000-3,500 years. The largest eruptions took place about 10,000 and 8300-8400 years ago, and three periods of longterm lava-dome growth have occurred. The latest eruptive cycle began about 3,000 years ago with a large explosion and was followed by lava-dome growth lasting intermittently about 1,000 years. An explosive eruption about 1,100 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.
Source: Kamchatkan Volcanic Eruption Response Team (KVERT) http://www.kscnet.ru/ivs/kvert/index_eng.php
PALUWEH Lesser Sunda Islands (Indonesia) 8.32°S, 121.708°E; summit elev. 875 m
Based on analysis of satellite imagery and other data, the Darwin VAAC reported that during 11-13 November ash plumes from Paluweh rose to an altitude of 2.4 km (8,000 ft) a.s.l. and drifted 90-150 km NW and W.
Geologic Summary. 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.
Source: Darwin Volcanic Ash Advisory Centre (VAAC) ftp://ftp.bom.gov.au/anon/gen/vaac
REVENTADOR Ecuador 0.077°S, 77.656°W; summit elev. 3562 m
On 9 November, IG reported that since February Reventador began a new phase of activity characterized by lava flows from the crater, steam plumes, and thermal anomalies detected in satellite images. The lava flows traveled as far as 2 km down the N and S flanks, and steam plumes rose 200-500 m above the crater. Field visits by volcanologists in recent months confirmed that the lava dome in the crater had continued to grow above the rim, becoming the highest point of the volcano. Blocks from the lava dome and lava-flow fronts rolled down the flanks. IG noted that during 3-4 November emissions increased; a steam-and-ash plume rose 3 km above the crater. The seismic network detected an increase in the magnitude of volcanic tremor. Steam-and-gas plumes contained ash within the previous few days.
According to the Washington VAAC, the IG reported that on 9 November an ash emission from Reventador rose to an unknown height. On 13 November a gas-and-ash plume rose to an altitude of 5.2 km (17,000 ft) a.s.l. and drifted SE. Ash was not detected in satellite imagery on either day.
Geologic Summary. Reventador is the most frequently active of a chain of Ecuadorian volcanoes in the Cordillera Real, well E of the principal volcanic axis. It is a forested stratovolcano that rises above the remote jungles of the western Amazon basin. A 3-km-wide caldera breached to the E was formed by edifice collapse and is partially filled by a young, unvegetated stratovolcano that rises about 1,300 m above the caldera floor. Reventador has been the source of numerous lava flows as well as explosive eruptions that were visible from Quito in historical time. Frequent lahars in this region of heavy rainfall have constructed a debris plain on the eastern floor of the caldera.
Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG) http://www.igepn.edu.ec/,
Washington Volcanic Ash Advisory Center (VAAC) http://www.ssd.noaa.gov/VAAC/messages.html
VILLARRICA Central Chile 39.42°S, 71.93°W; summit elev. 2847 m
According to Projecto Observación Visual Volcán Villarrica (POVI), incandescence from Villarrica's crater subsided mid-April and was undetected by satellite and ground observations at least through 10 November. Images captured by a camera in Pucon (16 km N) on 10 November showed an increase in the plume intensity. Small water vapor plumes, 50 m wide, rose from the depths of the crater.
Geologic Summary. Villarrica, one of Chile's most active volcanoes, rises above the lake and town of the same name. It is the westernmost of three large stratovolcanoes that trend perpendicular to the Andean chain. A 6-km wide caldera formed during the late Pleistocene, more than 0.9 million years ago. A 2-km-wide postglacial caldera is located at the base of the presently active, dominantly basaltic-to-andesitic cone at the NW margin of the Pleistocene caldera. About 25 scoria cones dot Villarrica's flanks. Plinian eruptions and pyroclastic flows have been produced during the Holocene from this dominantly basaltic volcano, but historical eruptions have consisted largely of mild-to-moderate explosive activity with occasional lava effusion. Lahars from the glacier-covered volcano have damaged towns on its flanks.
Source: Projecto Observación Visual Volcán Villarrica (POVI) http://www.povi.cl/
Ongoing Activity
FUEGO Guatemala 14.473°N, 90.880°W; summit elev. 3763 m
INSIVUMEH reported that during 8-9 and 11-12 November explosions from Fuego ejected incandescent material 100-200 m above the lava dome, and produced ash plumes that rose 200-430 m and drifted W and SW. Avalanches were generated near the crater. During 8-9 and 11-13 November lava flows traveled 200-500 m SSW down the Ceniza drainage, producing incandescent block avalanches that reached vegetated areas.
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/
KARYMSKY Eastern Kamchatka (Russia) 54.05°N, 159.45°E; summit elev. 1536 m
KVERT reported that moderate seismic activity continued at Karymsky during 2-9 November. Satellite imagery detected a thermal anomaly on the volcano during 7-8 November. The Aviation Color Code remained at Orange. Based on analyses of satellite imagery, the Tokyo VAAC reported that on 10 November a possible eruption produced a plume that rose to an altitude of 5.5 km (18,000 ft) a.s.l. and drifted E.
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.
Sources: Kamchatkan Volcanic Eruption Response Team (KVERT) http://www.kscnet.ru/ivs/kvert/index_eng.php,
Tokyo Volcanic Ash Advisory Center (VAAC) http://ds.data.jma.go.jp/svd/vaac/data/vaac_list.html
KILAUEA Hawaii (USA) 19.421°N, 155.287°W; summit elev. 1222 m
During 7-13 November HVO reported that the circulating lava lake periodically rose and fell in the deep pit within Kilauea's Halema'uma'u Crater. Occasional measurements indicated that the gas plume from the vent continued to deposit variable amounts of spatter and Pele's hair onto nearby areas. Lava flows were active in the Royal Gardens subdivision and flowed across the coastal plain, but were about 500 m from the coast.
Activity at Pu'u 'O'o Crater remained elevated. Lava circulated within the perched lava lake at the NE pit at Pu'u 'O'o Crater, and glow emanated from vents at the S edge of the crater floor and from a spatter cone at the N edge. Small lava flows issued a few times from the westernmost vent at the S edge of the crater floor.
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/
LOKON-EMPUNG Sulawesi 1.358°N, 124.792°E; summit elev. 1580 m
Based on a SIGMET, the Darwin VAAC reported that on 11 November an ash plume from Lokon-Empung rose to an altitude of 1.5 km (5,000 ft) a.s.l.
Geologic Summary. The twin volcanoes Lokon and Empung, rising about 800 m above the plain of Tondano, are among the most active volcanoes of Sulawesi. Lokon, the higher of the two peaks (whose summits are only 2.2 km apart) has a flat, craterless top. The morphologically younger Empung volcano has a 400-m-wide, 150-m-deep crater that erupted last in the 18th century, but all subsequent eruptions have originated from Tompaluan, a 150 x 250 m wide double crater situated in the saddle between the two peaks. Historical eruptions have primarily produced small-to-moderate ash plumes that have occasionally damaged croplands and houses, but lava-dome growth and pyroclastic flows have also occurred.
Source: Darwin Volcanic Ash Advisory Centre (VAAC) ftp://ftp.bom.gov.au/anon/gen/vaac
RUAPEHU North Island (New Zealand) 39.28°S, 175.57°E; summit elev. 2797 m
On 5 November, GeoNet reported that Ruapehu's summit Crater Lake was hot during field visits in December 2011 and January 2012, exhibiting temperatures over 35 degrees Celsius. The lake cooled afterwards, reaching 16 degrees in May and fluctuating between 18-24 degrees during June-October. Scientists visited the lake in late October and reported that the water temperature was 19.5 degrees. During that visit they observed weak convection near the center of the blue-green lake.
GeoNet noted that Ruapehu is often seismically active; during the last month weak volcanic tremor was recorded and more recently several small earthquakes under the volcano had been detected. The largest earthquake was an M 2.
An overflight on 26 October to measure gas flux revealed that sulfur dioxide was 63 tonnes per day and carbon dioxide was 908 tonnes per day. The Aviation Colour Code remained at Green and the Volcanic Alert Level remained at 1 (signs of volcano unrest).
Geologic Summary. Ruapehu, one of New Zealand's most active volcanoes, is a complex stratovolcano constructed during at least four cone-building episodes. The 110 cu km volcanic massif is elongated in a NNE-SSW direction and is surrounded by another 100 cu km ring plain of volcaniclastic debris. A single historically active vent, Crater Lake, is located in the broad summit region, but at least five other vents on the summit and flanks have been active during the Holocene. Frequent mild-to-moderate explosive eruptions have occurred in historical time from the Crater Lake vent. Lahars produced by phreatic eruptions from the summit crater lake are a hazard to a ski area on the upper flanks and to river valleys below the volcano.
Source: New Zealand GeoNet Project http://www.geonet.org.nz/
SAKURA-JIMA Kyushu 31.585°N, 130.657°E; summit elev. 1117 m
JMA reported that during 5-9 November explosions from Sakura-jima's Showa Crater ejected tephra as far as 1.3 km from the crater. Very small eruptions at Minami-dake Crater occurred during 8-9 November. Based on information from JMA, the Tokyo VAAC reported that explosions during 7-12 November produced plumes that rose to altitudes of 1.2-3 km (4,000-10,000 ft) a.s.l. and drifted S, SE, and E. During 8-9 November pilots observed ash plumes that rose to altitudes of 2.4-4 km (8,000-13,000 ft) a.s.l. and drifted SE and E.
Geologic Summary. Sakura-jima, one of Japan's most active volcanoes, is a post-caldera cone of the Aira caldera at the northern half of Kagoshima Bay. Eruption of the voluminous Ito pyroclastic flow was associated with the formation of the 17 x 23-km-wide Aira caldera about 22,000 years ago. The construction of Sakura-jima began about 13,000 years ago and built an island that was finally joined to the Osumi Peninsula during the major explosive and effusive eruption of 1914. Activity at the Kita-dake summit cone ended about 4,850 years ago, after which eruptions took place at Minami-dake. Frequent historical eruptions, recorded since the 8th century, have deposited ash on Kagoshima, one of Kyushu's largest cities, located across Kagoshima Bay only 8 km from the summit. The largest historical eruption took place during 1471-76.
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
SHIVELUCH Central Kamchatka (Russia) 56.653°N, 161.360°E; summit elev. 3283 m
Based on visual observations and analyses of satellite data, KVERT reported that during 2-9 November a viscous lava flow continued to effuse on the NW flank of Shiveluch's lava dome, accompanied by hot avalanches and fumarolic activity. Satellite imagery showed a daily thermal anomaly on the lava dome. During 10-12 November weak seismicity was registered and satellite imagery showed a thermal anomaly. Video images recorded gas-and-steam activity, which contained ash on 12 November. 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 12 November ash plumes rose to altitudes of 3-4.3 km (10,000-14,000 ft) a.s.l. and drifted S.
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.
Sources: Kamchatkan Volcanic Eruption Response Team (KVERT) http://www.kscnet.ru/ivs/kvert/index_eng.php,
Tokyo Volcanic Ash Advisory Center (VAAC) http://ds.data.jma.go.jp/svd/vaac/data/vaac_list.html
TONGARIRO North Island (New Zealand) 39.13°S, 175.642°E; summit elev. 1978 m
On 5 November, GeoNet reported that several teams of scientists had been visiting Tongariro's Te Mari Craters to service portable seismometers (complementing four permanent installations), sample gas vents, and collect samples of ejecta. The report noted that not many earthquakes had been recorded recently, and that the hottest gas vent was 235 degrees Celsius while the others ranged from 95-104 degrees. On 30 October the sulfur dioxide flux was 154 tonnes per day and the carbon dioxide flux was 477 tonnes per day. The volcano continued to actively degas. The Aviation Colour Code remained at Yellow and the Volcanic Alert Level remained at 1 (signs of volcano unrest).
Geologic Summary. Tongariro is a large andesitic volcanic massif, located immediately NE of Ruapehu volcano, that is composed of more than a dozen composite cones constructed over a period of 275,000 years. Vents along a NE-trending zone extending from Saddle Cone (below Ruapehu volcano) to Te Mari crater (including vents at the present-day location of Ngauruhoe) were active during a several hundred year long period around 10,000 years ago, producing the largest known eruptions at the Tongariro complex during the Holocene. The youngest cone of the complex, Ngauruhoe, has grown to become the highest peak of the massif since its birth about 2500 years ago. The symmetrical, steep-sided Ngauruhoe, along with its neighbor Ruapehu to the south, have been New Zealand's most active volcanoes during historical time.
Source: New Zealand GeoNet Project http://www.geonet.org.nz/
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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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