All times are local unless otherwise stated.

Bulusan | 1 December-7 December 2010 | New Activity / Unrest Cite this Report
Bulusan Luzon (Philippines)	PHIVOLCS reported that volcanic earthquakes from Bulusan were detected during 1-6 December; no earthquakes were recorded on 7 December. Steam from known thermal vents rose 100 m and drifted SW on 1 December. Cloud cover prevented visual observations during 2-4 and 6-7 December. Diffuse steam rose from the crater and from known vents on 5 December. The Alert Level remained at 1 (on a scale of 0-5). Source: Philippine Institute of Volcanology and Seismology (PHIVOLCS)
Klyuchevskoy | 1 December-7 December 2010 | New Activity / Unrest Cite this Report
Klyuchevskoy Central Kamchatka (Russia)	KVERT reported that seismic activity at Kliuchevskoi was slightly above background levels during 26-27 November, and did not exceed background levels during 28 November-3 December. Satellite imagery showed gas-and-ash plumes drifting 430 km N and NE during 26-29 November and a weak thermal anomaly over the crater on 26, 28, and 29 November. Ash plumes were seen rising to an altitude of 6.3 km (20,700 ft) a.s.l. on 26 and 29 November and 1 December. Ash fell in Kozyrevsk (about 50 km W) on 27 November and in Klyuchi (30 km NNE) on 28 November. Strombolian activity was observed on 1 and 2 December. The Aviation Color Code level remained at Orange. Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Merapi | 1 December-7 December 2010 | New Activity / Unrest Cite this Report
Merapi Central Java	CVGHM reported that activity at Merapi declined during 1-3 December. Seismic data showed a decrease in the number of earthquakes as well as amplitude of the events. Deformation measurements did not show any significant changes. Although fog often prevented visual observations or views through webcams, gas plumes were seen rising 500 m above the crater and drifting W. Sulfur dioxide plumes were no longer detected in satellite imagery. CVGHM noted that lahar deposits were seen in multiple drainages and that several bridges had been recently damaged by lahar activity. On 4 December, the Alert Level was lowered to 3 (on a scale of 1-4). Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
Tengger Caldera | 1 December-7 December 2010 | New Activity / Unrest Cite this Report
Tengger Caldera Eastern Java	On 6 December, CVGHM reported that seismicity from Tengger Caldera's Bromo cone had declined since 30 November, and deformation measurements showed deflation. White-to-gray plumes rose 200-300 m above the crater rim and drifted N. The Alert Level was lowered to 3 (on a scale of 1-4). Residents and tourists were not permitted within a 2-km-radius of the active crater. Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
Tungurahua | 1 December-7 December 2010 | New Activity / Unrest Cite this Report
Tungurahua Ecuador	During 2-3 December, IG reported that Strombolian activity from Tungurahua was seen at night. Ash plumes on 3 December rose to an altitude of 8 km (26,200 ft) a.s.l. and ashfall was reported in nearby areas. On 4 December, a sudden increase in tremor detected by the seismic network was followed by intense roaring noises, an increase in the number and intensity of explosions, and window and ground vibrations. Pyroclastic flows descended the N and W drainages at 0939 and continued to occur in those and additional drainages until 1522, including Cusúa, Mandur, and Juive (NW), as well as Rea, Choglontús, and Mapayacu (SW). Ashfall occurred in uninhabited regions to the S and SE. According to news articles, people within 8 km of the summit were evacuated. On 5 December, satellite images showed ash plumes drifting SW. Ashfall was reported in areas within 8 km SW, W, NNW, and NW. Explosions caused windows to vibrate. During 5-6 December, blocks ejected from Strombolian activity rolled 1 km down the flanks. On 6 December, ash plumes rose to an altitude of 8 km (26,200 ft) a.s.l. and drifted NW, W and SW, causing ashfall downwind. Gas-and-ash plumes on 7 December rose to altitudes of 7-8 km (23,000-26,200 ft) a.s.l. and drifted SW and W. Ashfall resulted in deposits up to 1 mm thick in areas to the W. Ejected blocks rolled 1-2 km down the flanks and explosions vibrated windows. Sources: Reuters, Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN)

Aira | 1 December-7 December 2010 | Continuing ActivityCite this Report
Aira Kyushu (Japan)	Based on information from JMA, the Tokyo VAAC reported that during 1-7 December explosions from Sakura-jima produced plumes that rose to altitudes of 1.2-2.7 km (4,000-9,000 ft) a.s.l. and drifted E, SE, W, NW, and N. During 2 and 4-5 December, pilots reported that ash plumes rose to altitudes of 1.5-4.6 km (5,000-15,000 ft) a.s.l. Source: Tokyo Volcanic Ash Advisory Center (VAAC)
Dukono | 1 December-7 December 2010 | Continuing ActivityCite this Report
Dukono Halmahera	Based on analyses of satellite imagery, the Darwin VAAC reported that during 3-5 December ash plumes from Dukono rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted 55-110 km W. Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Fuego | 1 December-7 December 2010 | Continuing ActivityCite this Report
Fuego South-Central Guatemala	Based on analysis of satellite imagery, the Washington VAAC reported that on 4 December a diffuse plume of gas and possibly ash drifted SW. On 6 December, INSIVUMEH reported that explosions produced ash plumes that rose 900 m above the crater and drifted 6 km SW. Sources: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH), Washington Volcanic Ash Advisory Center (VAAC)
Karymsky | 1 December-7 December 2010 | Continuing ActivityCite this Report
Karymsky Eastern Kamchatka (Russia)	KVERT reported that seismic activity at Karymsky was above background levels during 26 November-3 December, suggesting that possible ash plumes rose to an altitude of 5.3 km (17,400 ft) a.s.l. during 25-26 and 30 November, and 1-2 December. Thermal anomalies were detected in satellite imagery on 26 and 27 November, and 1 December. The Aviation Color Code level remained at Orange. Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Kilauea | 1 December-7 December 2010 | Continuing ActivityCite this Report
Kilauea Hawaiian Islands (USA)	During 1-7 December, HVO reported that activity at Kilauea continued from the summit caldera and the east rift zone. At the summit caldera, the level of the lava-pool surface in the deep pit within Halema'uma'u crater remained mostly stable at approximately 135 m below the crater floor, periodically rising about 15 m above that level. Nighttime incandescence has been visible from the Jaggar Museum on the NW caldera rim since early 2010. A plume from the vent mostly drifted SW and deposited ash and fresh spatter nearby. At the east rift zone, lava flowed a short distance through the TEB lava-tube system before breaking out onto the surface at a saddle between two rootless shields at around the 610 m elevation on 1 December. Lava started to build a shield and also extended several hundred meters from both sides of the lava tube. A small breakout lava flow on top of the pali traveled 100 m downslope to within about 6 km of Kalapana Gardens. During 2-7 December, lava flows at the saddle area advanced W, N, and E. Lava was last observed entering the ocean at Puhi-o-Kalaikini during 29-30 November. Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
Machin | 1 December-7 December 2010 | Continuing ActivityCite this Report
Machin Colombia	According to INGEOMINAS, Observatory Vulcanológico and Sismológico de Manizales reported increased seismicity from Cerro Machín on 3 December. About 340 volcano-tectonic earthquakes with low magnitudes were located SW of the main lava dome, at an average depth of 4 km. The largest event, a M 3.7 earthquake located SW of the dome at a depth of about 3.5 km, was felt by local residents. The Alert level remained at III (Yellow; "changes in the behavior of volcanic activity"). Source: Servicio Geológico Colombiano (SGC)
Popocatepetl | 1 December-7 December 2010 | Continuing ActivityCite this Report
Popocatepetl Mexico	CENAPRED noted that steam-and-gas emissions rose from Popocatépetl during 1-7 December. Based on a SIGMET notice, the Washington VAAC reported that a small and brief emission of gas and ash on 5 December was too small or diffuse to be detected in satellite images. Sources: Centro Nacional de Prevencion de Desastres (CENAPRED), Washington Volcanic Ash Advisory Center (VAAC)
Sangay | 1 December-7 December 2010 | Continuing ActivityCite this Report
Sangay Ecuador	Based on information from Guayaquil MWO, the Washington VAAC reported ash from Sangay on 5 December; weather clouds prevented satellite observations. IG noted elevated seismicity. Source: Washington Volcanic Ash Advisory Center (VAAC)
Sheveluch | 1 December-7 December 2010 | Continuing ActivityCite this Report
Sheveluch Central Kamchatka (Russia)	KVERT reported that moderate seismic activity from Shiveluch was detected during 26 November-3 December. A bright thermal anomaly over the volcano was observed in satellite imagery. Strong gas-and-steam activity was observed on 26 and 29 November. Satellite images showed ash plumes drifting 153 km N and NE during 29-30 November, as well as several ash clouds (as large as 81 by 16 km) at distances as far as 351 km N and NE. Seismic data analysis suggested that ash plumes rose to an altitude of 5.5 km (18,000 ft) a.s.l. on 1 December. The Aviation Color Code level remained at Orange. Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Soufriere Hills | 1 December-7 December 2010 | Continuing ActivityCite this Report
Soufriere Hills Montserrat	MVO reported that during 26 November-3 December activity from the Soufrière Hills lava dome was at a low level. Part of the large unstable overhanging area on the W side of the lava dome collapsed on 29 November, generating pyroclastic flows that traveled about 2 km W. Small pyroclastic flows also occurred on the E side of the dome. On 2 December, small areas of incandescence were visible on the back wall of the 11 February collapse scar. The Hazard Level remained at 3. Source: Montserrat Volcano Observatory (MVO)
Suwanosejima | 1 December-7 December 2010 | Continuing ActivityCite this Report
Suwanosejima Ryukyu Islands (Japan)	Based on information from JMA, the Tokyo VAAC reported explosions from Suwanose-jima during 1-4 December. Plumes rose to an altitude of 1.2 km (4,000 ft) and drifted SE on 4 December. Source: Tokyo Volcanic Ash Advisory Center (VAAC)

Weekly Reports Archive

Since the Weekly Volcanic Activity Report began in November 2000, there have been 19,386 individual reports over 1,186 weeks (average of 16 per week) on 331 different volcanoes.

Use the dropdowns to choose the year and week for archived Weekly Reports.

 News Feeds and Google Placemarks

 Criteria & Disclaimers

The Weekly Volcanic Activity Report does not necessarily include all volcanic activity that occurred on Earth during the week. More than a dozen volcanoes globally have displayed more-or-less continuous eruptive activity for decades or longer, and such routine activity is typically not reported here. Moreover, Earth's sea-floor volcanism is seldom reported even though in theory it represents the single most prolific source of erupted material. The Weekly Volcanic Activity Report summarizes volcanic activity that meets one or more of the following criteria:

- A volcano observatory raises or lowers the alert level at the volcano.
- A volcanic ash advisory has been released by a volcanic ash advisory center (VAAC) stating that an ash cloud has been produced from the volcano.
- A verifiable news report of new activity or a change in activity at the volcano has been issued.
- Observers have reported a significant change in volcanic activity. Such activity can include, but is not restricted to, pyroclastic flows, lahars, lava flows, dome collapse, or increased unrest.

Volcanoes are included in the "New Activity/Unrest" section of the Weekly Volcanic Activity Report if the activity occurs after at least 3 months of quiescence. Once a volcano is included in the "New Activity/Unrest" section, updates will remain in that section unless the activity continues for more than 1 month without escalating, after which time updates will be listed in the "Continuing Activity" section. Volcanoes are also included in the "New Activity/Unrest" section if the volcano is undergoing a period of relatively high unrest, or increasing unrest. This is commonly equal to Alert Level Orange on a scale of Green, Yellow, Orange, Red, where Red is the highest alert. Or alert level 3 on a scale of 1-4 or 1-5.

It is important to note that volcanic activity meeting one or more of these criteria may occur during the week, but may not be included in the Weekly Volcanic Activity Report because we did not receive a report.

1. The Weekly Volcanic Activity Report is intended to provide timely information about global volcanism on a weekly basis. Consequently, the report is generated rapidly by summarizing volcanic reports from various sources, with little time for fact checking. The accuracy of the Weekly Volcanic Activity Report is dependent upon the quality of the volcanic activity reports we receive. Reports published in the Bulletin of the Global Volcanism Network are cover longer time periods and are more carefully reviewed, although all of the volcanoes discussed in the Weekly Volcanic Activity Report are not necessarily reported in the Bulletin. Because of our emphasis on rapid reporting on the web we have avoided diacritical marks. Reports are updated on the Weekly Volcanic Activity Report web page as they are received, therefore information may be included regarding events that occurred before the current report period.

2. Rapidly developing events lead to coverage that is often fragmentary. Volcanoes, their eruptions, and their plumes and associated atmospheric effects are complex phenomena that may require months to years of data analysis in order to create a comprehensive summary and interpretation of events.

3. Preliminary accounts sometimes contain exaggerations and "false alarms," and accordingly, this report may include some events ultimately found to be erroneous or misleading.

4. 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.

5. USGS Disclaimer Statement for this Website:

Information presented on this website is considered public information and may be distributed or copied. Use of appropriate byline/photo/image credit is requested. We strongly recommend that USGS data be acquired directly from a USGS server and not through other sources that may change the data in some way. While USGS makes every effort to provide accurate and complete information, various data such as names, telephone numbers, etc. may change prior to updating. USGS welcomes suggestions on how to improve our home page and correct errors. USGS provides no warranty, expressed or implied, as to the accuracy, reliability or completeness of furnished data.

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U.S. Department of the Interior, U.S. Geological Survey, Reston, VA, USA
URL: https://volcano.si.edu/reports_weekly.cfm

 Acronyms and Abbreviations

a.s.l. - above sea level

AVO - Alaska Volcano Observatory

AVHRR - Advanced Very High Resolution Radiometer

CENAPRED - Centro Nacionale de Prevencion de Desastres (México)

CONRED - Coordinadora Nacional para la Reducción de Desastres

COSPEC - Correlation Spectrometer

CVGHM (formerly VSI) - Center of Volcanology and Geological Hazard Mitigation

CVO - Cascades Volcano Observatory (USGS)

GMS - Geostationary Meteorological Satellite

GOES - Geostationary Operational Environmental Satellite

GVO - Goma Volcano Observatory

GVP - Global Volcanism Program (Smithsonian Institution)

HVO - Hawaiian Volcano Observatory (USGS)

ICE - Instituto Costarricense de Electricidad (Costa Rica)

IG - Instituto Geofísico (Ecuador)

IGNS - Institute of Geological and Nuclear Sciences (New Zealand) - now GNS Science

INETER - Instituto Nicaragüense de Estudios Territoriales (Nicaragua)

INGEMMET - Instituto Geológical Minero y Metalúrgico (Peru)

INGEOMINAS - Instituto Colombiano de Geología y Minería (Colombia)

INGV-CT - Istituto Nazionale di Geofisica e Vulcanologia - Sezione di Catania (Italy)

INSIVUMEH - Instituto Nacional de Sismologia, Vulcanologia, Meteorologia e Hidrologia (Guatemala)

IRD - Institut de Recherche pour le Développement (France)

JMA - Japanese Meteorological Agency

KEMSD - Kamchatkan Experimental and Methodical Seismilogical Department

KVERT - Kamchatkan Volcanic Eruption Response Team

M - magnitude

METEOSAT - Meteorological Satellite

MEVO - Mount Erebus Volcano Observatory

MODIS - Moderate Resolution Imaging Spectroradiometer

MVO - Montserrat Volcano Observatory

MWO - Meteorological Watch Office

NEIC - National Earthquake Information Center

NIED - National Research Institute for Earth Science and Disaster Prevention (Japan)

NOAA - National Oceanic and Atmospheric Administration

NOTAM - Notice to Airmen

OVDAS - Observatorio Volcanologico de los Andes del Sur (Chile)

OFDA - Office of US Foreign Disaster Assistance

ONEMI - Oficina Nacional de Emergencia - Ministerio del Interior (Chile)

OVPDLF - Observatoire Volcanologique du Piton de la Fournaise (France)

OVSICORI-UNA - Observatorio Vulcanologico y Sismologico de Costa Rica, Universidad Nacional (Costa Rica)

PHIVOLCS - Philippine Institute of Volcanology and Seismology (Philippines)

RSAM - Real-time Seismic Amplitude Measurement

RVO - Rabaul Volcano Observatory

SERNAGEOMIN - Servicio Nacional de Geologia y Mineria (Chile)

SIGMET - Significant Meteorological Information

SNET - Servicio Nacional de Estudios Territoriales (El Salvador)

SVERT - Sakhalin Volcanic Eruption Response Team (Russia)

USAID - US Agency for International Development

USGS - United States Geological Survey

UTC - Coordinated Universal Time

VAAC - Volcanic Ash Advisory Center

VAFTAD - Volcanic Ash Forecast Transport And Dispersion

VDAP - Volcano Disaster Assistance Program (USGS)

VHP - Volcano Hazards Program (USGS)

VRC - Volcano Research Center (Japan)