All times are local unless otherwise stated.

Barren Island | 3 December-9 December 2008 | New Activity / Unrest Cite this Report
Barren Island Andaman Islands (India)	The Darwin VAAC reported that during 7-8 December pilots observed lava flows on Barren Island; ash plumes were not present. Thermal anomalies were detected on satellite imagery. Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Klyuchevskoy | 3 December-9 December 2008 | New Activity / Unrest Cite this Report
Klyuchevskoy Central Kamchatka (Russia)	KVERT reported that seismic activity at Kliuchevskoi was above background levels during 28 November-10 December; Strombolian activity ejected bombs 500 m above the crater and lava effusion on the NW flank continued. Analysis of satellite imagery revealed a large daily thermal anomaly in the crater. During 27-29 November, and 2 and 4 December, gas-and-steam plumes with little ash content rose to altitudes of 6-6.2 km (19,700-20,300 ft) a.s.l. and drifted 40-115 km NE, E, SE, and SW. During 4-5 December, the ash content in plumes increased. On 8 December, phreatic bursts occurred where the lava flow front contacted the Erman Glacier. On 9 December, a 50-km-wide ash plume drifted about 550 km ENE. The Level of Concern Color Code was raised to Red. KVERT warned that the activity was dangerous for international and low-flying aircraft. On 10 December, the Level of Concern Color Code was lowered back to Orange because explosive activity decreased. A gas-and-steam plume with a small amount of ash drifted NE. Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Nevado del Huila | 3 December-9 December 2008 | New Activity / Unrest Cite this Report
Nevado del Huila Colombia	INGEOMINAS reported that seismicity from Nevado del Huila continued to be elevated during 2-9 December. On 4 and 6 December overflights were conducted to view the new lava dome at the S flank of Pico Central. The dome elongated towards the SW of Pico Central, following the topography, and measured 400 m in the north-south direction, 150 m in the east-west direction, and was 120 m high. The approximate volume of the dome was 4,500,000 cubic meters. Gas plumes rose 1 km above the dome. New cracks in the glacier were also noted. Source: Servicio Geológico Colombiano (SGC)
Soufriere Hills | 3 December-9 December 2008 | New Activity / Unrest Cite this Report
Soufriere Hills Montserrat	MVO reported a total of four explosive events from the Soufrière Hills lava dome during 2-5 December. The first event was triggered by a small dome collapse on 2 December, occurred without precursory seismicity, and was followed by a pyroclastic flow on the W flank. Resultant ash plumes, accompanied by lightning strikes, rose to an altitude of 12.2 km (40,000 ft) a.s.l. and drifted W. Explosions ejected incandescent blocks up to 1.6 km away from the dome that landed on Gages Mountain (about 1 km WNW), leaving impact craters. The pyroclastic flow also generated multiple pyroclastic surges that traveled S and N, setting fire to trees and bushes. On 3 December another explosion scattered incandescent blocks all over the NW side of Gages Mountain. The third eruptive event, forceful emissions of ash on 4 December, resulted in ash plumes that rose to an altitude of 4.6 km (15,000 ft) a.s.l. The fourth explosive event occurred on 5 December and ejected incandescent blocks that were deposited on the NW side of Gages Mountain. A pyroclastic flow traveled to the W down Gages valley into Plymouth (about 5 km W) and an ash plume drifted NW. On 3, 4, and 5 December small, relatively slow moving pyroclastic flows traveled no more than 3.2 km down the Gages valley. In periods between the events, near-continuous emissions of ash-laden steam were noted. The Hazard Level remained at 3. According to the Washington VAAC, MVO reported eruptions on 6 December. Ash was seen on satellite imagery expanding in multiple directions, then to the E, SE, and W. Sources: Montserrat Volcano Observatory (MVO), Washington Volcanic Ash Advisory Center (VAAC)

Batu Tara | 3 December-9 December 2008 | Continuing ActivityCite this Report
Batu Tara Komba Island	Based on analysis of satellite imagery, the Darwin VAAC reported that during 6-7 December ash plumes from Batu Tara rose to an altitude of 1.5 km (5,000 ft) a.s.l. and drifted about 55 km NW and SW. Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Chaiten | 3 December-9 December 2008 | Continuing ActivityCite this Report
Chaiten Southern Chile	Based on observations of satellite imagery, pilot reports, SIGMET notices, and web camera views, the Buenos Aires VAAC reported that during 3-8 December, ash plumes from Chaitén rose to altitudes 1.8-4.6 km (6,000-15,000 ft) a.s.l. and drifted NE, NW, and SW. A thermal anomaly was detected on satellite imagery during 4 and 6-8 December. Source: Buenos Aires Volcanic Ash Advisory Center (VAAC)
Colima | 3 December-9 December 2008 | Continuing ActivityCite this Report
Colima Mexico	During 3-8 December, gray plumes from Colima rose to altitudes of 4.2-4.6 km (13,800-15,100 ft) a.s.l. and drifted N and W; a gray plume rose to an altitude of 6.4 km (21,000 ft) a.s.l. on 4 December. White plumes were also observed and, during 4-8 December, rose to a maximum altitude of 4.2 km (13,800 ft) a.s.l. The white plumes drifted SW and SE. Source: Gobierno del Estado de Colima
Karymsky | 3 December-9 December 2008 | Continuing ActivityCite this Report
Karymsky Eastern Kamchatka (Russia)	KVERT reported that seismic activity at Karymsky was at background levels during 27-30 November; possible explosions may have generated ash-and-gas plumes to an altitude of 3.7 km (12,100 ft) a.s.l. Analysis of satellite imagery revealed a thermal anomaly in the crater during 27-29 November and 1 December. The Level of Concern Color Code remained at Orange. Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Kilauea | 3 December-9 December 2008 | Continuing ActivityCite this Report
Kilauea Hawaiian Islands (USA)	HVO reported that during 3-9 December lava flowed SE through a tube system from underneath Kilauea's Thanksgiving Eve Breakout (TEB) and rootless shield complex, reaching the Waikupanaha ocean entry. Incandescence was occasionally seen at the TEB vent, and surface flows were noted on and at the base of the pali. On 6 December, a few explosions originated from the ocean entry. Observers reported that a small bench collapse that occurred sometime between 6 and 7 December sent boulders up to 0.5 m in diameter inland about 50-75 m. Earthquakes were variously located beneath and to the S of the caldera, along the SW rift zone, and along the S-flank fault. The vent in Halema'uma'u crater continued to produce a predominantly white plume that drifted mainly SW and deposited small amounts of tephra. Night-time incandescence was rarely seen at the base of the plume, and sounds resembling rockfalls were heard in the vicinity of the crater. During 2-4 December, the plume drifted NW and high concentrations of sulfur dioxide were measured at various locations. On 4 December, hybrid earthquakes were followed by several minutes of dense brown emissions. A vent rim collapse was seen on 5 December after rockfall and booming sounds were heard, and brown ash was emitted. The sulfur dioxide emission rate at the summit was 1,000 and 500 tonnes per day on 4 and 5 December, respectively; the 2003-2007 average rate was 140 tonnes per day. Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
Rabaul | 3 December-9 December 2008 | Continuing ActivityCite this Report
Rabaul New Britain (Papua New Guinea)	Based on analysis of satellite imagery and information from RVO, the Darwin VAAC reported that during 3-5, 7, and 9 December ash plumes from Rabaul caldera's Tavurvur cone rose to altitudes of 2.1-3 km (7,000-10,000 ft) a.s.l. and drifted E, NE, NNW, WNW, and W. Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Sheveluch | 3 December-9 December 2008 | Continuing ActivityCite this Report
Sheveluch Central Kamchatka (Russia)	KVERT reported that seismic activity at Shiveluch was above background levels during 28 November-5 December. Based on interpretations of seismic data, ash plumes rose to an altitude of 5.8 km (19,000 ft) a.s.l. According to visual observations, gas-and-steam plumes rose to an altitude of 3.5 km (11,500 ft) a.s.l. during 27 and 29-30 November, and 2 December. Analysis of satellite imagery revealed a daily thermal anomaly on the lava dome. The Level of Concern Color Code remained at Orange. Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Tongariro | 3 December-9 December 2008 | Continuing ActivityCite this Report
Tongariro North Island (New Zealand)	The Alert Level for Tongariro was lowered to 0 (typical background activity) on 2 December. The number of volcanic earthquakes declined to background levels since mid-2008. In addition, regular measurements of volcanic gas levels and the temperature of the summit gas vent showed no changes over the previous two and a half years. Source: GeoNet
Tungurahua | 3 December-9 December 2008 | Continuing ActivityCite this Report
Tungurahua Ecuador	The IG reported that on 4 December an ash plume from Tungurahua rose to an altitude of 7 km (23,000 ft) a.s.l. and drifted E. Light ashfall was reported in Runtún (6 km NNE) and Pondoa (about 8 km N). Cloud cover prevented visual observations during 5-9 December. Source: Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN)

Weekly Reports Archive

Since the Weekly Volcanic Activity Report began in November 2000, there have been 19,584 individual reports over 1,195 weeks (average of 16 per week) on 332 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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For site security purposes and to ensure that this service remains available to all users, this government computer system employs software programs to monitor network traffic to identify unauthorized attempts to upload or change information, or otherwise cause damage. Unauthorized attempts to upload information or change information on this website are strictly prohibited and may be punishable under the Computer Fraud and Abuse Act of 1986 and the National Information Infrastructure Protection Act. Information may also be used for authorized law enforcement investigations. (Last modified September 21, 1999.)

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)