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Smithsonian/USGS Weekly Volcanic Activity Report 7-13 March 2012
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Smithsonian/USGS Weekly Volcanic Activity Report
7-13 March 2012
Sally Kuhn Sennert - Weekly Report Editor
kuhns@si.edu
URL: http://www.volcano.si.edu/reports/usgs/
New Activity/Unrest: | Bezymianny, Central Kamchatka (Russia) | Cleveland, Chuginadak Island | Ijen, Eastern Java (Indonesia) | Iliamna, Southwestern Alaska | Lamongan, Eastern Java (Indonesia) | Marapi, Sumatra (Indonesia) | Nevado del Ruiz, Colombia | Tungurahua, Ecuador
Ongoing Activity: | Karymsky, Eastern Kamchatka (Russia) | Kilauea, Hawaii (USA) | Kizimen, Eastern Kamchatka (Russia) | Puyehue-Cordón Caulle, Central Chile | Sakura-jima, Kyushu | Santa María, Guatemala | Shiveluch, Central Kamchatka (Russia) | Villarrica, Central Chile
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
BEZYMIANNY Central Kamchatka (Russia) 55.978°N, 160.587°E; summit elev. 2882 m
KVERT reported that a strong explosive eruption from Bezymianny was detected by seismic instruments on 9 March. Ash plumes rose to altitudes of 3.5-5 km (11,500-16,400 ft) a.s.l. and drifted NE. During the most intense phase of the eruption ash plumes from pyroclastic flows rose to an altitude of 8 km (26,200 ft) a.s.l. Satellite imagery showed the plume drifting 700 km NE. 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. 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.
Geologic Summary. Prior to its noted 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.
Source: Kamchatkan Volcanic Eruption Response Team (KVERT) http://www.kscnet.ru/ivs/kvert/index_eng.php
CLEVELAND Chuginadak Island 52.825°N, 169.944°W; summit elev. 1730 m
AVO reported that a small explosion from Cleveland was detected at 1905 on 7 March by distant seismic stations and infrasound arrays. Weather conditions prevented the detection of a possible eruption cloud in satellite images or by visual observation of the summit. Another small explosion was detected at 1605 on 9 March and again weather conditions prevented observations. No other activity was detected during 11-13 March. The Volcano Alert Level remained at Watch and the Aviation Color Code remained at Orange. No current seismic information was available because Cleveland does not have a real-time seismic network.
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/
IJEN Eastern Java (Indonesia) 8.058°S, 114.242°E; summit elev. 2799 m
CVGHM raised the Alert Level for Ijen from 2 to 3 (on a scale of 1-4) on 12 March because of increased seismicity and visual observations. On 10 March scientists observed some plant damage around the crater lake and a 10-m-wide area of disrupted water on the crater-lake surface.
Geologic Summary. The Ijen volcano complex consists of a group of small stratovolcanoes constructed within the large 20-km-wide Ijen (Kendeng) caldera. The N caldera wall forms a prominent arcuate ridge, but elsewhere the caldera rim is buried by post-caldera volcanoes, including Gunung Merapi stratovolcano, which forms the 2,799 m high point of the Ijen complex. Immediately W of Gunung Merapi is the renowned historically active Kawah Ijen volcano, which contains a nearly 1-km-wide, turquoise-colored, acid crater lake. The picturesque lake is the site of a labor-intensive sulfur mining operation, in which sulfur-laden baskets are hand-carried from the crater floor. A half dozen small-to-moderate phreatic eruptions have taken place from Kawah Ijen during the 20th century.
Source: Center of Volcanology and Geological Hazard Mitigation (CVGHM) http://www.vsi.esdm.go.id/
ILIAMNA Southwestern Alaska 60.032°N, 153.090°W; summit elev. 3053 m
AVO reported that earthquake activity had steadily increased at Iliamna during the past three months. On 9 March AVO increased the Alert Level to Advisory and the Aviation Color Code to Yellow. The report noted that the current activity was characterized by numerous earthquakes that had varied in their number and magnitude over the past week.
Geologic Summary. 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.
Source: Alaska Volcano Observatory (AVO) http://www.avo.alaska.edu/
LAMONGAN Eastern Java (Indonesia) 7.979°S, 113.342°E; summit elev. 1651 m
CVGHM reported that during 1 February-9 March diffuse white plumes rose at most 20 m above Lamongan. Seismicity increased on 23 February, then fluctuated in intensity through 7 March. Seismicity increased significantly on 8 March and tremor was recorded continuously the next day. CVGHM raised the Alert Level to 2 (on a scale of 1-4) on 9 March. Residents and tourists were prohibited from going within a 1-km-radius of the active crater.
Geologic Summary. Lamongan, a small 1,631-m-high stratovolcano located between the massive Tengger and Iyang-Argapura volcanic complexes, is surrounded by numerous maars and cinder cones. The currently active cone has been constructed 650 m to the SW of Gunung Tarub, the volcano's high point. As many as 27 maars with diameters from 150 to 700 m, some containing crater lakes, surround the volcano, along with about 60 cinder cones and spatter cones. Lake-filled maars, including Ranu Pakis, Ranu Klakah, and Ranu Bedali, are located on the eastern and western flanks; dry maars are predominately located on the northern flanks. None of the Lamongan maars has erupted during historical time, although several of the youthful maars cut drainage channels from Gunung Tarub. Lamongan was very active from the time of its first historical eruption in 1799 through the end of the 19th century, producing frequent explosive eruptions and lava flows from vents on the western side of the volcano ranging from the summit to about 450 m elevation.
Source: Center of Volcanology and Geological Hazard Mitigation (CVGHM) http://www.vsi.esdm.go.id/
MARAPI Sumatra (Indonesia) 0.381°S, 100.473°E; summit elev. 2891 m
According to a news article from 5 March, several eruptions from Marapi produced ash plumes during the previous week. An ash plume rose 1 km above the crater on 4 March and drifted 10 km S. A representative from CVGHM noted that the Alert Level remained at 2 (on a scale of 1-4).
Geologic Summary. Gunung Marapi, not to be confused with the better known Merapi volcano on Java, is Sumatra's most active volcano. Marapi is a massive complex stratovolcano that rises 2,000 m above the Bukittinggi plain in Sumatra's Padang Highlands. A broad summit contains multiple partially overlapping summit craters constructed within the small 1.4-km-wide Bancah caldera. The summit craters are located along an ENE-WSW line, along which volcanism has migrated to the W. More than 50 eruptions, typically consisting of small-to-moderate explosive activity, have been recorded since the end of the 18th century; no historical lava flows outside the summit craters have been reported.
Source: BNO News http://channel6newsonline.com/2012/03/indonesias-mount-marapi-still-highly-active/
NEVADO DEL RUIZ Colombia 4.895°N, 75.322°W; summit elev. 5321 m
INGEOMINAS reported a significant increase in seismicity at Nevado del Ruiz during 5-11 March. On 8 March scientists aboard an overflight observed a gas plume that rose 1.4 km above Arenas crater, originating from multiple emission sources and thermally anomalous areas within the crater. They noted ash deposits on the glacier, near the crater rim and on the E flank, likely from an explosion on 22 February. Later that day a small explosion detected by the seismic network produced an ash emission that was observed with a camera installed in La Piranha (NW). Increased sulfur dioxide emissions were also detected. Fieldwork revealed ash deposits at the headwaters of Gualí River, SW of Arenas crater.
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.
Source: Instituto Colombiano de Geología y Minería (INGEOMINAS) http://www.ingeominas.gov.co/
TUNGURAHUA Ecuador 1.467°S, 78.442°W; summit elev. 5023 m
IG reported that, although visual observations of Tungurahua during 6-11 March were sometimes limited due to cloud cover, steam plumes were noted on 6 and 8 March, and a gas-and-ash plume that rose 500 m above the crater was observed on 7 March. Slight ashfall was reported in Choglontus (13 km WSW) on 7 March. An ash plume rose 1 km above the crater on 11 March and drifted SE. Lahars descended the Chacauco (NW) and Mapayacu (SW) drainages. The next day seismicity increased and an ash plume rose 2-3 km above the crater that drifted W and SW. During 12-13 March ashfall was reported in Choglontus and Manzano (8 km 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/
Ongoing Activity
KARYMSKY Eastern Kamchatka (Russia) 54.05°N, 159.45°E; summit elev. 1536 m
KVERT reported that during 2-9 March seismic activity from Karymsky continued to be detected and indicated that possible ash plumes rose to an altitude of 3.4 km (11,000 ft) a.s.l. on 3 March. Satellite imagery showed a thermal anomaly on the volcano on 2 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 7-13 March, HVO reported that the lava lake periodically rose and fell in the deep pit within Kilauea's Halema'uma'u Crater. Almost daily measurements indicated that the gas plume from the vent continued to deposit variable amounts of ash and fresh spatter nearby. Incandescence was visible from both a small pit on the NE edge and a small spatter cone on the SE edge of the Pu'u 'O'o crater floor, and on the upper part of the lava-tube system on the E flank. Lava flows continued to advance down the pali and across the coastal plain. On 12 March the leading edge of the flows were 9 km SE of Pu'u 'O'o and about 2 km from the coast.
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/
KIZIMEN Eastern Kamchatka (Russia) 55.130°N, 160.32°E; summit elev. 2376 m
KVERT reported moderate seismic activity at Kizimen during 2-9 March and a large thermal anomaly that was detected in satellite images. Video and satellite observations indicated both continued effusion of a large lava flow on the E flank and hot avalanches. 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
PUYEHUE-CORDON CAULLE Central Chile 40.590°S, 72.117°W; summit elev. 2236 m
Based on seismicity detected during 6-13 March, OVDAS-SERNAGEOMIN reported that the eruption from the Cordón Caulle rift zone, part of the Puyehue-Cordón Caulle volcanic complex, continued at a low level. Plumes observed most days in web camera and satellite images rose 0.3-1.2 km above the crater and drifted 30-50 km NNE, E, and SW. Incandescence from the crater was observed during 5-8 and 10-13 March. The Alert Level remained at Red.
Geologic Summary. The Puyehue-Cordón Caulle volcanic complex (PCCVC) is a large NW-SE-trending late-Pleistocene to Holocene basaltic-to-rhyolitic transverse volcanic chain SE of Lago Ranco. The 1799-m-high Pleistocene Cordillera Nevada caldera lies at the NW end, separated from Puyehue stratovolcano at the SE end by the Cordón Caulle fissure complex. The Pleistocene Mencheca volcano with Holocene flank cones lies NE of Puyehue. The basaltic-to-rhyolitic Puyehue volcano is the most geochemically diverse of the PCCVC. The flat-topped, 2236-m-high Puyehue volcano was constructed above a 5-km-wide caldera and is capped by a 2.4-km-wide summit caldera of Holocene age. Lava flows and domes of mostly rhyolitic composition are found on the eastern flank of Puyehue. Historical eruptions originally attributed to Puyehue, including major eruptions in 1921-22 and 1960, are now known to be from the Cordón Caulle rift zone. The Cordón Caulle geothermal area, occupying a 6 x 13 km wide volcano-tectonic depression, is the largest active geothermal area of the southern Andes volcanic zone.
Source: Servicio Nacional de Geología y Minería (SERNAGEOMIN) http://www.sernageomin.cl/
SAKURA-JIMA Kyushu 31.585°N, 130.657°E; summit elev. 1117 m
Based on information from JMA, the Tokyo VAAC reported that during 7-9 and 11-13 March explosions from Sakura-jima often produced plumes that rose to altitudes of 1.2-2.7 km (4,000-9,000 ft) a.s.l. and drifted E and SE. Pilots observed ash plumes during 9 and 11-13 March that rose to altitudes of 1.8-3 km (6,000-10,000 ft) a.s.l.
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.
Source: Tokyo Volcanic Ash Advisory Center (VAAC) http://www.ssd.noaa.gov/VAAC/OTH/JP/messages.html
SANTA MARIA Guatemala 14.756°N, 91.552°W; summit elev. 3772 m
INSIVUMEH reported that during 8-9 March explosions from Santa María's Santiaguito lava-dome complex generated ash plumes that rose 800-1,000 m above the crater and drifted W and SW. Block avalanches descended the SE and NW flanks. Ashfall was reported in the communities of Loma Linda, San Marcos, and Palajunoj. During 11-12 March explosions generated ash plumes that rose 800 m above the crater and drifted 20 km SSW. Ashfall was reported at the observatory, on the El Faro and Patzulin ranches, and in the village of Las Marías. Lava flows continued to produce avalanches.
Geologic Summary. Symmetrical, forest-covered Santa María volcano is one of a chain of large stratovolcanoes that rises dramatically above the Pacific coastal plain of Guatemala. The stratovolcano has a sharp-topped, conical profile that is cut on the SW flank by a large, 1-km-wide crater, which formed during a catastrophic eruption in 1902 and extends from just below the summit to the lower flank. The renowned Plinian eruption of 1902 followed a long repose period and devastated much of SW Guatemala. The large dacitic Santiaguito lava-dome complex has been growing at the base of the 1902 crater since 1922. Compound dome growth at Santiaguito has occurred episodically from four westward-younging vents, accompanied by almost continuous minor explosions and periodic lava extrusion, larger explosions, pyroclastic flows, and lahars.
Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
http://www.insivumeh.gob.gt/
SHIVELUCH Central Kamchatka (Russia) 56.653°N, 161.360°E; summit elev. 3283 m
KVERT reported that seismic activity at Shiveluch was low during 2-9 March. Ground-based observers and satellite imagery indicated that a viscous lava flow continued to effuse in the crater formed during a 2010 eruption. Moderate fumarolic activity at the lava dome was observed during 2 and 5-8 March; cloud cover prevented observations on the other days. Satellite imagery showed a weak thermal anomaly over the lava dome during 3, 5, and 7-8 March. The Aviation Color Code remained at Orange.
Based on information from KVERT, the Tokyo VAAC reported that on 10 March an ash plume rose to an altitude of 5.2 km (17,000 ft) a.s.l. and drifted NE. Yelizovo Airport (UHPP) reported that an ash plume rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted SW.
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://www.ssd.noaa.gov/VAAC/OTH/JP/messages.html
VILLARRICA Central Chile 39.42°S, 71.93°W; summit elev. 2847 m
According to Projecto Observación Visual Volcán Villarrica (POVI), two small ash emissions from Villarrica occurred on 7 March. Incandescence from the crater was observed from the town of Pucon (16 km N) during 7-8 March.
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/
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