The launch of a new GVP website is scheduled for Monday, May 20, 2013.
Ongoing Activity: | Bezymianny, Kamchatka | Colima, México | Etna, Italy | Guagua Pichincha, Ecuador | Karangetang, Indonesia | Kilauea, USA | Komaga-take, Japan | Piton de la Fournaise, Réunion Island | Popocatepetl, México | Soufriere Hills, Montserrat | 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.
Ongoing Activity
BEZYMIANNY Kamchatka Peninsula, Russia 55.98°N, 160.59°E; summit elev. 2,882 m
The increase in seismicity that began on 30 October reportedly ended when seismicity decreased to background levels sometime during 3-10 November. Only gas-and-steam plumes were observed rising to a maximum height of 2 km above the volcano. KVERT lowered the Level of Concern Color Code from Yellow to Green.
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: KVERT via Alaska Volcano Observatory
Bezymianny Information from the Global Volcanism Program
COLIMA western México 19.514°N,103.62°W; summit elev. ~3,850 m; All times are local (= UTC - 6 hours)
The Volcanological Observatory of Colima University reported that small exhalations occurred at Colima at 1250 on 8 November, 1327 on 9 November, and at 1728 on 10 November. The Mexico City MWO reported that the 10 November exhalation produced an ash cloud that rose to 6 km a.s.l. and was blown to the ENE. The Washington VAAC reported that the ash cloud was not visible in GOES-8 imagery. According to the observatory, the events did not exceed the established safety limits so the zone of exclusion remained at 6.5 km around the volcano.
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 north and the historically active Volcan de Colima at the south. Volcan de Colima (also known as Volcan 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 repetitively from both the Nevado and Fuego cones, and have produced a thick apron of debris-avalanche deposits on three sides of the complex. Frequent historical eruptions have mostly originated from Colima's summit crater. The current eruptive episode began in November 1998 and has included summit lava dome growth to feed three SW-flank lava flows, pyroclastic flows, and intermittent explosive activity.
Sources: Volcanological Observatory of Colima University, and the Washington VAAC
Colima Information from the Global Volcanism Program
ETNA Sicily, Italy 37.73°N, 15.00°E; summit elev. 3,315 m
According to the Italy's Volcanoes website, during the week mild Strombolian activity continued at the Bocca Nuova Crater. The overall level of activity appeared to be generally lower than the previous week.
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.
Sources: Italy's Volcanoes: The Cradle of Volcanology, Sistema Poseidon, and Stromboli On-line
Etna Information from the Global Volcanism Program
GUAGUA PICHINCHA north-central Ecuador 0.17°S, 78.60°W; summit elev. 4,784 m
Volcanic activity at Guagua Pichincha was low during the week and seismicity was relatively stable. No dramatic changes in the morphology of the lava dome were observed.
Geologic Summary. Guagua Pichincha rises immediately west of Quito, Ecuador's capital city. The broad volcanic massif is cut by a large horseshoe-shaped summit caldera, ~6 km in diameter and 600 m deep, that was breached to the W during a slope failure ~50,000 years ago. Subsequent late-Pleistocene and Holocene eruptions from the central vent consisted of explosive activity with pyroclastic flows accompanied by periodic lava dome growth and destruction. A major eruption in 1660 deposited 30 cm of ash in Quito, but most of the many eruptions since the Spanish colonial era have been minor. The latest eruptive period began with phreatic explosions in 1998. Magmatic eruptions first occurred in October 1999, and intermittent eruptions of varying scale since have blanketed Quito and surrounding towns with ash.
Source: Instituto Geofísico
Guagua Pichincha Information from the Global Volcanism Program
KARANGETANG [Api Siau] Siau Island, Indonesia 2.47°N, 125.29°E; summit elev. 1,784 m; All times are local (= UTC + 9 hours)
The VSI reported that volcanic activity continued at Karangetang. At 2030 on 2 November a small explosion produced an ash cloud that reached a height of 1.5 km above the volcano. The ejected material fell around the summit and flowed 1.5 km down the E, S, and W flanks of the volcano. A "red flame" was observed some nights rising ~ 75 m above the volcano's summit.
Geologic Summary. Karangetang (also known as Api Siau) lies at the northern end of the island of Siau, N of Sulawesi, and contains five summit craters strung along a N-S line. One of Indonesia's most active volcanoes, Karangetang has had more than 40 recorded eruptions since 1675. Twentieth-century eruptions have included frequent explosions, sometimes accompanied by pyroclastic flows and lahars.
Source: VSI
Karangetang Information from the Global Volcanism Program
KILAUEA Hawaii, USA 19.43°N, 155.29°W; summit elev. 1,222 m
Lava continued to flow across the coastal flat and into the sea at the Kamokuna entry. Overall, volcanic tremor near Pu`u `O`o vent remained at a moderate level and earthquake activity was low across the island. The tilt-meters at Kilauea's summit and along the east rift zone showed flat signals.
Geologic Summary. Kilauea, one of five coalescing volcanoes that comprise the island of Hawaii, is one of the world's most active volcanoes. Historically its eruptions 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. The latest Kilauea eruption began in January 1983 along the E rift zone. The Pu`u `O`o-Kupaianaha eruption is now in its 18th year and 55th eruptive episode. Since 1986, flows have traveled 11-12 km from the vents to the sea, paving about 80 km2 of land on the S flank of Kilauea and building 205 hectares of new land.
Sources: US Geological Survey Hawaiian Volcano Observatory
Kilauea Information from the Global Volcanism Program
KOMAGA-TAKE Hokkaido, Japan 42.07°N, 140.68°E; summit elev. 1,140 m; All times are local (= UTC + 9 hours)
According to an Associated Press article, the JMA stated that at 0739 on 8 November an eruption occurred at Komaga-take, which is 710 km NE of Tokyo on Japan's northernmost island of Hokkaido. The eruption produced an ash cloud and coincided with 10 minutes of volcanic tremor. Ashfall was reported in the nearby town of Shikabe, but due to cloudy conditions the height of the ash plume was not observed. The volcano had previously erupted on 4 and 28 September, and 28 October 2000.
Geologic Summary. Komaga-take volcano on the Oshima Peninsula of southern Hokkaido is one of the most active volcanoes of Japan's northernmost island. The truncated volcano contains a breached crater that formed as a result of edifice collapse. Hummocky debris-avalanche material occurs at its base on three sides. The volcano's first historical eruption in 1640 began a period of more frequent explosive activity. The 1640 eruption, one of the largest in Japan during historical time, deposited ash as far away as central Honshu and produced a debris avalanche that reached the sea. The resulting tsunami caused 700 fatalities. Additional large eruptions took place in 1856 and 1929, but the volcano was quiescent from 1942 until minor eruptions in 1996, 1998, and 2000.
Sources: Associated Press and the Australian Broadcasting Company
Komaga-take Information from the Global Volcanism Program
PITON DE LA FOURNAISE Réunion Island, Indian Ocean 21.23°S, 55.71°E; summit elev. 2,631 m
According to OVPDLF, the eruption that began on 12 October at Piton de la Fournaise continued through 13 November. A new cone named "Piton Morgabim" developed in the beginning of November and on 8 November a 10- to 15-km-diameter lava lake formed, which had intense degassing and heavy lava fountaining. During the course of the eruption, 4.5-km-long lava flows formed E of the volcano in the "Grand Brûlé" area, and ~2-km-long lava flows issued from "Piton Morgabim."
Geologic Summary. The massive Piton de la Fournaise shield volcano on the island of Réunion is one of the world's most active volcanoes. Most historical eruptions have originated from the summit and flanks of a 400-m-high lava shield, Dolomieu, that has grown within the youngest of three large calderas. This depression is 8 km wide and is breached to below sea level on the eastern side. More than 150 eruptions, most of which have produced fluid basaltic lava flows within the caldera, have been documented since the 17th century.
Source: OVPDLF
Piton de la Fournaise Information from the Global Volcanism Program
POPOCATÉPETL Mexico 19.02°N, 98.62°W; summit elev. 5,426 m; All times are local (= UTC - 6 hours)
During the week volcanic activity was high at Popocatepetl, with several exhalations and eruptions. CENAPRED reported that exhalations at 1456 and 1541 on 7 November sent ash clouds to 2 and 4.5 km above the volcano, respectively. The Mexico City MWO reported to the Washington VAAC that an ash-and-steam exhalation at 1150 on 9 November sent ash to ~9.5 km a.s.l. According to a Reuters article, CENAPRED stated that light ashfall occurred in Santiago Xalitzintla, the closest village to the crater. The Washington VAAC reported that on 11 November eruptions at 0739, 0818, 0845, and 1418 sent ash to a maximum altitude of ~9.5 km a.s.l. The volcano's Alert Level remained at Yellow Phase III.
Geologic Summary. Popocatepetl, 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.
Map, Photos (CENAPRED Internet Site)
Sources: CENAPRED, Washington VAAC, Reuters, and the Associated Press
Popocatepetl Information from the Global Volcanism Program
SOUFRIERE HILLS Montserrat, West Indies 16.72°N, 62.18°W; summit elev. 1,013 m
The MVO reported that during 3-10 November, volcanism continued at an elevated level and seismicity was slightly higher than the previous week. Dome growth continued and rockfalls occurred on the E side of the crater. Heavy rainfall on 4 and 8 November produced mudflows that traveled to the NW down the Belham River. During the 8 November rainfall, continuous rockfalls and low-energy pyroclastic flows traveled to the E down the Tar River valley. The pyroclastic flows generated ash clouds that rose to ~2 km a.s.l. and were blown to the N. On 13 November the Washington VAAC reported that a low-level (~1.5 km a.s.l.) ash plume that was blown to the N was visible in GOES-8 imagery.
Geologic Summary. The complex andesitic Soufriere Hills volcano occupies the southern half of the island of Montserrat. The summit area consists primarily of a series of lava domes emplaced along an ESE-trending zone. Non-eruptive seismic swarms occurred at 30-year intervals in the 20th century, but the first well-documented historical eruption on Montserrat did not take place until 1995. Long-term small-to-moderate ash eruptions were accompanied by lava dome growth and pyroclastic flows that initially forced evacuation of the southern half of the island and then destroyed the capital city of Plymouth, causing severe social and economic disruption. The volcano is currently in a period of new dome growth.
Source: Montserrat Volcano Observatory
Soufriere Hills Information from the Global Volcanism Program
TUNGURAHUA Ecuador 1.47°S, 78.44°W; summit elev. 5,023 m
The IG reported that seismicity and explosive activity were at low levels during the week. The Washington VAAC reported that on 13 November a small ash cloud, which was near summit level and blown to the SE, was visible in GOES-8 imagery.
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. The volcano's historical eruptions have been restricted to 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 the evacuation of the town of Baños on the N side of the volcano.
Sources: Instituto Geofísico and the Washington VAAC
Tungurahua Information from the Global Volcanism Program
Additional Reports of Volcanic Activity by Country
The following websites have frequently updated activity reports on volcanoes in addition to those that meet the criteria for inclusion in the Weekly Volcanic Activity Report. The websites are organized by country and are maintained by various agencies.
Indonesia, Italy, New Zealand, United States and Russia
URL: http://www.volcano.si.edu/reports/usgs/
