Saturday, November 30, 2013

[ Volcano ] Smithsonian/USGS Weekly Volcanic Activity Report 13-19 November 2013



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Smithsonian/USGS Weekly Volcanic Activity Report 13-19 November 2013
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Smithsonian/USGS Weekly Volcanic Activity Report

13-19 November 2013

Sally Kuhn Sennert - Weekly Report Editor

kuhns@si.edu

URL: http://www.volcano.si.edu/reports/usgs/

New Activity/Unrest: | Colima, México border | Etna, Sicily (Italy) | Merapi, Central Java (Indonesia) | Sinabung, Sumatra (Indonesia) | Yasur, Vanuatu (SW Pacific)

Ongoing Activity: | Bagana, Bougainville | Chirinkotan, Kuril Islands | Chirpoi, Kuril Islands (Russia) | Copahue, Central Chile-Argentina | Fuego, Guatemala | Karymsky, Eastern Kamchatka (Russia) | Kilauea, Hawaii (USA) | Manam, Northeast of New Guinea (SW Pacific) | Rabaul, New Britain | Shiveluch, Central Kamchatka (Russia) | Ulawun, New Britain

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

COLIMA México 19.514°N, 103.62°W; summit elev. 3850 m

The Washington VAAC reported that at 0730 on 17 November a possible ash emission from Colima produced a plume that drifted almost 20 km E.

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

ETNA Sicily (Italy) 37.734°N, 15.004°E; summit elev. 3330 m

INGV reported that weak Strombolian explosions from Etna's New Southeast Crater (NSEC) were visible on 13 November. INGV-Osservatorio Etneo staff visited the area the next day and noted that explosions were heard one to three times per minute, and during times of good visibility no pyroclastic material was ejected. Sporadic ejections of incandescent pyroclastics were observed after nightfall. Early on 16 November Strombolian activity gradually intensified; however, only pulsating puffs of vapor, but no ash, were produced.

On 17 November a new paroxysmal eruptive episode was characterized by violent Strombolian activity and pulsating lava fountains, emission of lava flows that traveled S, ESE, and NE, and the formation of an eruption column charged with pyroclastic material that drifted NE. The episode ended with a long series of powerful explosions and loud bangs heard tens of kilometers away. Strombolian activity continued until the late evening; after nightfall, a small lava flow issued from an effusive vent located on the lower E flank of the NSEC cone.

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: INGV Sezione di Catania - Osservatorio Etneo www.ct.ingv.it/

MERAPI Central Java (Indonesia) 7.542°S, 110.442°E; summit elev. 2968 m

According to news articles, a phreatic eruption at Merapi on 18 November produced an ash plume that rose 2 km above the crater and caused ashfall in areas as far as 60 km E. About 600 families from the Glagaharjo village gathered at evacuation assembly points, while others on the W flank evacuated then returned to their homes hours later.

Geologic Summary. Merapi, one of Indonesia's most active volcanoes, lies in one of the world's most densely populated areas and dominates the landscape immediately N of the major city of Yogyakarta. The steep-sided modern Merapi edifice, its upper part unvegetated due to frequent eruptive activity, was constructed to the SW of an arcuate scarp cutting the eroded older Batulawang volcano. Pyroclastic flows and lahars accompanying growth and collapse of the steep-sided active summit lava dome have devastated cultivated and inhabited lands on the volcano's western-to-southern flanks and caused many fatalities during historical time. The volcano is the object of extensive monitoring efforts by the Merapi Volcano Observatory (MVO).

Source: Jakarta Post http://www.thejakartapost.com/news/2013/11/19/hundreds-villagers-flee-mount-merapi-eruptio ns.html

SINABUNG Sumatra (Indonesia) 3.17°N, 98.392°E; summit elev. 2460 m

Based on webcam data and satellite images, the Darwin VAAC reported that during 13-14 November an ash plume from Sinabung rose to an altitude of 3.7 km (12,000 ft) a.s.l. and drifted almost 150 km NW and W. According to a news article, a pyroclastic flow traveled 1.2 km down the SE flank on 14 November, prompting more evacuations from villages near the base of the volcano. The article noted that more than 7,000 people had been evacuated from 10 villages.

An explosion observed with the webcam on 18 November produced an ash plume that rose to an altitude of 7.6 km (25,000 ft) a.s.l. About 30 minutes later an ash plume also visible in satellite images rose to an altitude of 11.3 km (37,000 ft) a.s.l. and drifted 65 km W. Four hours later satellite images showed ash plumes at an altitude of 9.1 km (30,000 ft) a.s.l. to the W of Sinabung and at an altitude of 4.6 km (15,000 ft) a.s.l. over the crater. On 19 November the webcam recorded an ash plume that rose to an altitude of 4.6 km (15,000 ft) a.s.l. over the crater. A news article stated that later that night that an ash plume rose to an altitude of 10 km (32,800 ft) a.s.l.

A news article from 20 November noted that volcanologists updated the hazard map for Sinabung. The second-tier disaster-prone area, previously defined as a radius of 2-3 km from Sinabung's crater, was expanded to 4-5 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.

Sources: Darwin Volcanic Ash Advisory Centre (VAAC) ftp://ftp.bom.gov.au/anon/gen/vaac/

Jakarta Post http://www.thejakartapost.com/news/2013/11/15/volcanic-ash-n-sumatra-floods-w-papua-force- villagers-flee.html

Jakarta Post http://www.thejakartapost.com/news/2013/11/20/mt-sinabung-record-breaking-ash-cloud.html

Jakarta Post http://www.thejakartapost.com/news/2013/11/20/scientists-redraw-hazard-map-mt-sinabung.htm l

YASUR Vanuatu (SW Pacific) 19.53°S, 169.442°E; summit elev. 361 m

On 19 November, the Vanuatu Geohazards Observatory reported that a new phase of ash emissions from Yasur began on 3 November. The intensity of the explosive activity remained low; therefore the Alert Level remained at 1 (on a scale of 0-4).

Geologic Summary. Yasur, the best-known and most frequently visited of the Vanuatu volcanoes, has been in more-or-less continuous Strombolian and vulcanian activity since Captain Cook observed ash eruptions in 1774. This style of activity may have continued for the past 800 years. Yasur is a mostly unvegetated pyroclastic cone with a nearly circular, 400-m-wide summit crater. Yasur is largely contained within the small Yenkahe caldera in SE Tanna Island. It is the youngest of a group of Holocene volcanic centers constructed over the down-dropped NE flank of the Pleistocene Tukosmeru volcano. Active tectonism along the Yenkahe horst accompanying eruptions of Yasur has raised Port Resolution harbor more than 20 m during the past century.

Source: Vanuatu Geohazards Observatory http://www.geohazards.gov.vu/

Ongoing Activity

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 during 14-18 November ash plumes from Bagana rose to an altitude of 2.7 km (9,000 ft) a.s.l. and drifted 35-110 km W and SW.

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

CHIRINKOTAN Kuril Islands 48.980°N, 153.480°E; summit elev. 724 m

SVERT reported that during 13-15 November a thermal anomaly over Chirinkotan was observed, as well as steam-and-gas emissions during 14-15 November. 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 from Snow, a volcano of Chirpoi, was detected in satellite images during 13-15 November. 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

COPAHUE Central Chile-Argentina border 37.85°S, 71.17°W; summit elev. 2997 m

Based on ODVAS webcam views and satellite images, the Buenos Aires VAAC reported that on 15 November a low-level diffuse plume from Copahue drifted almost 40 km NW. Later that night a thermal anomaly was detected by satellite and light from a full moon allowed webcam views of a possible ash emission. The next day steam-and-gas emissions were observed with the webcam. The Alert Level remained at Yellow.

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: Buenos Aires Volcanic Ash Advisory Center (VAAC) http://www.smn.gov.ar/vaac/buenosaires/productos.php

FUEGO Guatemala 14.473°N, 90.880°W; summit elev. 3763 m

On 18 November INSIVUMEH reported that during the previous week explosions from Fuego produced ash plumes that rose 450-750 m and drifted W and SW. Some of the explosions generated rumbling noises, shock waves detected within 15 km, and rattled structures in Panimaché (8 km SW), Panimaché II (8 km SW), Morelia (9 km SW), Santa Sofía (12 km SW), and Sangre de Cristo (8 km WSW). A 600-m-long lava flow was active on the SE flank, and block avalanches that descended the Ceniza drainage (SSW) reached vegetated areas. Ashfall was reported in Panimaché, Morelia, and Sangre de Cristo.

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 at Karymsky was detected during 8-15 November. Satellite images detected a daily thermal anomaly on the volcano, possibly indicating weak Vulcanian and Strombolian activity. Ash plumes drifted 140 km SE and E during 9-10 November. 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 November HVO reported that the circulating lava lake occasionally rose and fell in the deep pit within Kilauea's Halema'uma'u Crater. 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. On 18 November the southernmost spatter cone produced a lava flow that after a few hours burst out in a dome fountain; lava spread over much of the S crater floor before stopping about 30 minutes later. The 7.1-km-long Kahauale'a 2 lava flow, fed by the NE spatter cone, was active with scattered break-out flows and burned the forest N 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/

MANAM Northeast of New Guinea (SW Pacific) 4.080°S, 145.037°E; summit elev. 1807 m

RVO reported that both Manam's Southern Crater and Main Crater were quiet during 1 October-15 November. White vapor emissions rose from Southern Crater and on some days were slightly bluish. Light gray ash clouds and bright incandescence were visible on 31 October. Main Crater only produced white vapor plumes.

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)

RABAUL New Britain 4.271°S, 152.203°E; summit elev. 688 m

RVO reported that Rabaul caldera's Tavurvur cone was quiet during 1-12 November. At 0516 on 13 November a moderate explosion generated a dense billowing ash cloud that rose 1 km above the crater and drifted NW. A few more explosions continued after that, at irregular intervals; notably on 14 November at 0738, 0851, 1308, 2044, and on 15 November at 1903. Ash plumes from these events also drifted NW. During 1-15 November seismicity was very low, except for events associated with the explosions. Deformation measurements showed slight inflation of the central part of the caldera; the long-term inflationary trend continued.

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)

SHIVELUCH Central Kamchatka (Russia) 56.653°N, 161.360°E; summit elev. 3283 m

KVERT reported that during 8-15 November several strong explosions from Shiveluch generated ash plumes that rose to a maximum altitude of 7 km (24,600 ft) a.s.l. Viscous lava continued to effuse onto the N and NE flanks of the lava dome, accompanied by hot avalanches, incandescence, ash explosions, and fumarolic activity. A daily thermal anomaly was detected 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://ds.data.jma.go.jp/svd/vaac/data/vaac_list.html

ULAWUN New Britain 5.05°S, 151.33°E; summit elev. 2334 m

RVO reported that during 1 October-15 November activity at Ulawun was low; small volumes of white vapor and gray and gray-brown ash plumes rose 100 m above the crater and drifted S. Seismicity was low with RSAM values fluctuating between 100 and 150 units throughout the period.

Geologic Summary. The symmetrical basaltic to andesitic Ulawun stratovolcano is the highest volcano of the Bismarck arc, and one of Papua New Guinea's most frequently active. Ulawun rises above the N coast of New Britain opposite Bamus volcano. The upper 1,000 m of the 2,334-m-high volcano is unvegetated. A steep-walled valley cuts the NW side of the volcano, and a flank lava-flow complex lies to the S of this valley. Historical eruptions date back to the beginning of the 18th century. Twentieth-century eruptions were mildly explosive until 1967, but after 1970 several larger eruptions produced lava flows and basaltic pyroclastic flows, greatly modifying the summit crater.

Source: Rabaul Volcano Observatory (RVO)

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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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