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Smithsonian/USGS Weekly Volcanic Activity Report 13-19 June 2012
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Smithsonian/USGS Weekly Volcanic Activity Report
13-19 June 2012
Sally Kuhn Sennert - Weekly Report Editor
kuhns@si.edu
URL: http://www.volcano.si.edu/reports/usgs/
New Activity/Unrest: | Fuego, Guatemala | Galeras, Colombia | Manam, Northeast of New Guinea (SW Pacific) | Nevado del Ruiz, Colombia | Sirung, Pantar Island (Indonesia)
Ongoing Activity: | Batu Tara, Komba Island (Indonesia) | Cleveland, Chuginadak Island | Dukono, Halmahera | Karymsky, Eastern Kamchatka (Russia) | Kilauea, Hawaii (USA) | Popocatépetl, México | Sakura-jima, Kyushu | Shiveluch, Central Kamchatka (Russia) | 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
FUEGO Guatemala 14.473°N, 90.880°W; summit elev. 3763 m
INSIVUMEH reported that during 14-15 and 17-18 June explosions from Fuego produced ash plumes that rose 300-800 m above the crater and drifted WSW, E, and NE. Explosions generated rumbling sounds and shock waves detected in areas as far as 6 km away. Tephra avalanches descended the SW flank, into the Ceniza drainage, and lava flowed 200 m SW, into the Taniluya drainage. Pulses of incandescence rose 50-75 m above the crater. During 18-19 June lava flows advanced 50 m and block avalanches 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/
GALERAS Colombia 1.22°N, 77.37°W; summit elev. 4276 m
INGEOMINAS reported that during 5-19 June seismicity at Galeras had increased in both magnitude and frequency since the previous week-long period, and indicated continuing ash and gas emissions. On 5, 6, and 12-19 June cameras recorded gas-and-ash emissions; an ash plume rose 1.4 and 2.4 km above the crater on 14 and 17 June, respectively. Ashfall was reported in Sandona (13 km NW), Samaniego (32 km NW), Mapachico (8 km NW), and Genoy (5 km NE). Sulfur dioxide emissions were moderate to high. The Alert Level remained at III (Yellow; "changes in the behavior of volcanic activity").
Geologic Summary. Galeras, a stratovolcano with a large breached caldera located immediately W of the city of Pasto, is one of Colombia's most frequently active volcanoes. The dominantly andesitic Galeras volcanic complex has been active for more than 1 million years, and two major caldera collapse eruptions took place during the late Pleistocene. Longterm extensive hydrothermal alteration has affected the volcano. This has contributed to large-scale edifice collapse that has occurred on at least three occasions, producing debris avalanches that swept to the W and left a large horseshoe-shaped caldera inside which the modern cone has been constructed. Major explosive eruptions since the mid Holocene have produced widespread tephra deposits and pyroclastic flows that swept all but the southern flanks. A central cone slightly lower than the caldera rim has been the site of numerous small-to-moderate historical eruptions since the time of the Spanish conquistadors.
Source: Instituto Colombiano de Geología y Minería (INGEOMINAS) http://www.ingeominas.gov.co/
MANAM Northeast of New Guinea (SW Pacific) 4.080°S, 145.037°E; summit elev. 1807 m
RVO reported low-to-moderate activity from Manam's Southern Crater during 1-15 June. Emissions consisted of gray and sometimes black ash clouds that rose from the crater on most days. Plumes drifted SE on 2 June and NW during 6-15 June. Ash fell in areas downwind between Yassa (WSW) and Baliau (NNW), and Warisi (ESE). Incandescent material was ejected from the crater, and roaring and rumbling noises were noted. Pyroclastic flows on 16 June (at 0700, 0720, 0722, and 0729) channeled into the SE valley. The last pyroclastic flow was perhaps the largest as it reached the lowest elevation, 300-400 m above sea level, but was far from populated areas. Ash plumes from the pyroclastic flows drifted WSW and WNW; ash fell in Bogia (22 km SSW, on the mainland). Emissions from Main Crater were milder and mostly characterized by white and bluish plumes. Light gray plumes were noted during 2 and 8-9 June. Fluctuating incandescence was intermittently observed and ash fell in the NW part of the island.
Geologic Summary. The 10-km-wide island of Manam, lying 13 km off the northern coast of mainland Papua New Guinea, is one of the country's most active volcanoes. Four large radial valleys extend from the unvegetated summit of the conical 1807-m-high basaltic-andesitic stratovolcano to its lower flanks. These "avalanche valleys," regularly spaced 90 degrees apart, channel lava flows and pyroclastic avalanches that have sometimes reached the coast. Two summit craters are present; both are active, although most historical eruptions have originated from the southern crater, concentrating eruptive products during much of the past century into the SE avalanche valley. Frequent historical eruptions, typically of mild-to-moderate scale, have been recorded at Manam since 1616. Occasional larger eruptions have produced pyroclastic flows and lava flows that reached flat-lying coastal areas and entered the sea, sometimes impacting populated areas.
Source: Rabaul Volcano Observatory (RVO)
NEVADO DEL RUIZ Colombia 4.895°N, 75.322°W; summit elev. 5321 m
According to INGEOMINAS, the Observatorio Vulcanológico and Sismológico de Manizales reported on 15 June that satellite image analyses and field observers of Nevado del Ruiz indicated significant sulfur dioxide emissions. Seismic signals on 15 and 18 June indicated continuing ash emissions. Based on analysis of satellite imagery and web camera views, the Washington VAAC reported that on 17 June a 5.5-km-wide gas plume, possibly containing ash, drifted more than 90 km NW. The VAAC noted on 18 June that INGEOMINAS reported a gas-and-ash plume drifting N and NW at an altitude of 6.1 km (20,000 ft) a.s.l. The plume was later detected in satellite imagery drifting more than 90 km NW. The Alert Level remained at II (Orange; "eruption likely within days or weeks") on 19 June.
Geologic Summary. Nevado del Ruiz is a broad, glacier-covered volcano in central Colombia that covers >200 sq km. Three major edifices, composed of andesitic and dacitic lavas and andesitic pyroclastics, have been constructed since the beginning of the Pleistocene. The modern cone consists of a broad cluster of lava domes built within the summit caldera of an older Ruiz volcano. The 1-km-wide, 240-m-deep Arenas crater occupies the summit. Steep headwalls of massive landslides cut the flanks of Nevado del Ruiz. Melting of its summit icecap during historical eruptions, which date back to the 16th century, has resulted in devastating lahars, including one in 1985 that was South America's deadliest eruption.
Sources: Instituto Colombiano de Geología y Minería (INGEOMINAS) http://www.ingeominas.gov.co/,
Washington Volcanic Ash Advisory Center (VAAC) http://www.ssd.noaa.gov/VAAC/messages.html
SIRUNG Pantar Island (Indonesia) 8.508°S, 124.13°E; summit elev. 862 m
CVGHM reported that during 1-13 June diffuse white plumes from Sirung rose 30-70 m above the crater. A sulfur odor was occasionally noted at the Sirung observation post. Based on seismic activity and visual observations, on 15 June CVGHM reiterated that the Alert Level remained at 2 (on a scale of 1-4).Visitors and tourists were not permitted to go within a 1.5 km radius of Sirung.
Geologic Summary. Sirung volcano is located at the NE end of a 14-km-long line of volcanic centers that form a peninsula at the southern end of Pantar Island. The low, 862-m-high volcano is truncated by a 2-km-wide caldera whose floor often contains one or more small lakes. Much of the volcano is constructed of basaltic lava flows, and the Gunung Sirung lava dome forms the high point on the caldera's western rim. A number of phreatic eruptions have occurred from vents within the caldera during the 20th century.
Source: Center of Volcanology and Geological Hazard Mitigation (CVGHM) http://proxy.vsi.esdm.go.id/index.php
Ongoing Activity
BATU TARA Komba Island (Indonesia) 7.792°S, 123.579°E; summit elev. 748 m
Based on analyses of satellite imagery, the Darwin VAAC reported that on 18 June ash plumes from Batu Tara rose to an altitude of 2.4 km (8,000 ft) a.s.l. and drifted 110-150 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
CLEVELAND Chuginadak Island 52.825°N, 169.944°W; summit elev. 1730 m
AVO reported that during 12-19 June meteorological cloud cover often prevented satellite views of Cleveland. Elevated surface temperatures at the summit were detected using infrared imagery during 12-13 and 18-19 June. A pilot report, a web camera image, and infrasound data all indicated that an ash-producing explosion occurred around 1405 on 19 June. The pilot report suggested that the cloud altitude was 10 km (35,000 ft) a.s.l. and the infrasound data indicated that the eruption duration was short. The Volcano Alert Level was raised to Watch and the Aviation Color Code was raised to Orange.
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/
DUKONO Halmahera 1.68°N, 127.88°E; summit elev. 1335 m
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.
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
KARYMSKY Eastern Kamchatka (Russia) 54.05°N, 159.45°E; summit elev. 1536 m
KVERT reported that moderate seismic activity from Karymsky continued to be detected during 8-15 June, and indicated that possible ash plumes rose to an altitude of 3 km (9,800 ft) a.s.l. during 8-13 June. Meteorological cloud cover prevented satellite image views. Based on analysis of seismic data, KVERT reported that on 18 June possible ash plumes rose to an altitude of 3 km (10,000 ft) a.s.l. 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 13-19 June HVO reported that the lava lake periodically rose and fell in the deep pit within Kilauea's Halema'uma'u Crater. Periodic measurements indicated that the gas plume from the vent continued to deposit variable amounts of ash and Pele's hair onto nearby areas. The lava pond in a small pit on the E edge of Pu'u 'O'o crater floor was visible with the web cameras, and on 15 June was 7-8 m below the rim. Incandescence emanated from two vents along the S edge of the crater floor, and a lava flow issued from a south-central vent on 14 June. Lava flows were active on the coastal plain and traveled as far as 1.1 km from the ocean. Lava flows were also sometimes active on the pali.
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/
POPOCATEPETL México 19.023°N, 98.622°W; summit elev. 5426 m
CENAPRED reported that during 13-19 June meteorological cloud cover often prevented observations of Popocatépetl's crater. Incandescence from the crater was occasionally visible at night. During 13-15 June gas-and-ash plumes that rose above the crater sometimes drifting NW and W. Ejected tephra fell onto the E, N, and W flanks, as far away as 500 m from the crater. The Alert Level remained at Yellow Phase Three.
Geologic Summary. Popocatépetl, whose name is the Aztec word for smoking mountain, towers to 5,426 m 70 km SE of Mexico City and is North America's second-highest volcano. Frequent historical eruptions have been recorded since the beginning of the Spanish colonial era. A small eruption on 21 December 1994 ended five decades of quiescence. Since 1996 small lava domes have incrementally been constructed within the summit crater and destroyed by explosive eruptions. Intermittent small-to-moderate gas-and-ash eruptions have continued, occasionally producing ashfall in neighboring towns and villages.
Source: Centro Nacional de Prevencion de Desastres (CENAPRED) http://www.cenapred.unam.mx/es/
SAKURA-JIMA Kyushu 31.585°N, 130.657°E; summit elev. 1117 m
JMA reported that during 11-15 June large explosive eruptions from Sakura-jima's Showa Crater occurred five times and ejected tephra as far as 800 m from the crater. A small eruption from Minami-dake Crater occurred on 13 June.
Based on information from JMA, the Tokyo VAAC reported that during 13-15 and 17-19 June explosions produced plumes that rose to altitudes of 1.8-3.4 km (6,000-11,000 ft) a.s.l. and drifted multiple directions. A pilot observed an ash plume on 19 June that rose to an altitude of 3.4 (11,000 ft) a.s.l. and drifted 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/,
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
KVERT reported that during 8-15 June explosive activity at Shiveluch continued. During 11-13 June a thermal anomaly on the lava dome was detected in satellite imagery and ground-based observers noted strong gas-and-steam activity. Seismic data indicated that a possible ash plume rose to an altitude of 8 km (26,200 ft) a.s.l. Meteorological cloud cover prevented observations of the volcano on the other days. Based on analyses of seismic data and information from KEMSD, the Tokyo VAAC reported that an eruption on 15 June produced an ash plume that rose to an altitude of 8.2 km (27,000 ft) a.s.l. Ash was not detected in satellite images. Based on analysis of seismic data, KVERT reported that on 18 June possible ash plumes rose to altitudes of 3.4-4 km (11,200-13,100 ft) a.s.l. 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.
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
TUNGURAHUA Ecuador 1.467°S, 78.442°W; summit elev. 5023 m
IG reported that during 13-19 June visual observations of Tungurahua were limited due to cloud cover. On 13 June ash plumes rose 2-2.5 km above the crater and drifted NE and N. Ashfall was reported in Cusúa (8 km NW) and Bilbao (8 km W). An explosion the next day caused windows to vibrate in areas 8 km SW and N. Steam plumes rose 0.5-2 km above the crater during 16-18 June. Windows in Manzano (8 km SW) vibrated during 18-19 June, and ashfall was reported in Palitagua, Runtún (6 km NNE), and Choglontús (SW).
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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