Smithsonian/USGS Weekly Volcanic Activity Report 12-18 March 2014
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Smithsonian/USGS Weekly Volcanic Activity Report
12-18 March 2014
Sally Kuhn Sennert - Weekly Report Editor kuhns@si.edu
URL: http://www.volcano.si.edu/reports/usgs/
New Activity/Unrest: | Ubinas, Perú
Ongoing Activity: | Aira, Kyushu | Chirinkotan, Kuril Islands | Chirpoi, Kuril Islands (Russia) | Colima, México border | Dukono, Halmahera | Etna, Sicily (Italy) | Karymsky, Eastern Kamchatka (Russia) | Kilauea, Hawaii (USA) | Santa María, Guatemala | 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
UBINAS Perú 16.355°S, 70.903°W; summit elev. 5672 m
Based on analyses of satellite imagery, the Buenos Aires VAAC reported that diffuse plumes from Ubinas, possibly containing ash, drifted WNW on 13 March and SW on 15 March. Satellite images on 16 March showed a diffuse gas plume containing some ash drifting WSW.
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.
Source: 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 10-14 March two 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. Volcanologists conducting a field survey on 10 March noted that sulfur dioxide emissions were 190 tons per day, lower than the 1,900 tons per day they measured on 4 March. The Alert Level remained at 3 (on a scale of 1-5).
The Tokyo VAAC reported explosions during 12 and 15-17 March. On 12 March pilots observed ash plumes that rose to altitudes of 1.2-1.8 km (4,000-6,000 ft) a.s.l. and drifted N. During 15-18 March plumes rose to altitudes of 1.8-2.7 km (6,000-9,000 ft) a.s.l. and drifted E, SE, and S. Pilots observed ash plumes drifting SE at an altitude of 3.4 km (11,000 ft) a.s.l. on 16 March, and drifting SE at an altitude of 3 km (10,000 ft) a.s.l. on 18 March.
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
CHIRINKOTAN Kuril Islands 48.980°N, 153.480°E; summit elev. 724 m
SVERT reported that a thermal anomaly over Chirinkotan was observed in satellite images on 10 and 13 March. Steam-and-gas emissions were observed on 10 March and drifted more than 40 km SW on 12 March. Cloud cover obscured views on the other days during 11-17 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 thermal anomaly over Snow, a volcano of Chirpoi, was detected in satellite images during 10-12 March. Diffuse steam-and-gas emissions were observed on 15 March. Cloud cover obscured views during 13-14 and 16-17 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 12 March an ash plume from Colima drifted 25 km NNE and dissipated.
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 on 14 March an ash plume from Dukono rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted 90-160 km NW. During 16-17 March ash plumes drifted 130-150 km SW at an altitude of 2.4 km (8,000 ft) a.s.l.
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 17 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. Lava flows originating from a vent on the upper wall traveled towards the upper part of the W wall of the Valle del Bove. During 14-15 March lava also flowed 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 7-14 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 120 km SW on 12 March and 300 km SE on 13 March. Satellite images detected an ash plume that rose to altitudes of 1.5-2 km (3,300-6,600 ft) a.s.l. and drifted 100 km SE on 17 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 12-18 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. 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. On 12 March lava flowed S from the S cone. Once on 14 March and twice on 17 March lava from the pond rose and spilled over the rim.
Breakouts from the stalled main lobe of the Kahauale'a 2 lava flow continued to advance and burned adjoining forest. A satellite image from 11 March showed that the edge of the most distant breakout flow was 8 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/
SANTA MARIA Guatemala 14.756°N, 91.552°W; summit elev. 3772 m
INSIVUMEH reported that during 13-14 March an explosion from Santa María's Santiaguito lava-dome complex generated an ash plume that rose 700 m and drifted SW, causing ashfall in areas within 3 km including La Florida and Monte Claro. During 15-18 March gas plumes rose as high as 150 m and small avalanches from lava flows descended the E and SE flanks.
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 during 7-14 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 8-15 March based on observations from a post in the Ndokum Siroga village, 8.5 km away. Dense white plumes rose from the lava dome daily, as high as 1 km on most days; plumes rose 2 km on 12 March. Incandescent material originating from various parts of the lava dome traveled up to 2 km S and SE. Tremor and volcanic earthquakes were detected, and signals representing avalanches from the unstable and still-growing dome increased. Sulfur dioxide emissions varied between 300 and 598 tons per day. Observations on 13 March showed that lava from the dome had flowed 2.4 km downslope. The report also noted that three people burned during a pyroclastic flow on 1 February later died in the hospital bringing the total number of casualties from that day to 17. 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 11-16 March, but then declined during 17-18 March; cloud cover occasionally prevented observations. On 11 March rain caused major lahars in the Achupashal drainage which led to traffic disruption on the Baños- Penipe highway. Ash plumes on 12 March rose 1 km above the crater. On 14 March ash plumes rose 3 km and drifted W and SE. Sounds resembling blocks rolling down the flanks were reported by residents in Runtún (6 km NNE).
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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