All times are local unless otherwise stated.

Concepcion (Nicaragua) | 9 December-15 December 2009 | New Activity / Unrest Cite this Report
Concepcion Central America Volcanic Arc	According to a news article, INETER reported that an explosion of ash and gas from Concepción on 11 December produced a plume that rose 150 m above the crater. Ashfall was reported in three nearby communities. Source: Reuters
Galeras (Colombia) | 9 December-15 December 2009 | New Activity / Unrest Cite this Report
Galeras Northern Andean Volcanic Arc	INGEOMINAS reported that observations of Galeras during an overflight on 3 December revealed thermal anomalies in the main crater measuring 155 degrees Celsius. During 8-11 December, seismic activity decreased, although some seismic signals resembled patterns seen prior to previous eruptions. Sulfur dioxide emissions were low. Seismicity increased on 12 December; earthquakes M 2.2 and less were detected within 2 km of the summit and at depths up to 3 km below the summit during 12-15 December. The Alert Level was raised to II (Orange; "probable eruption in term of days or weeks"). Source: Servicio Geológico Colombiano (SGC)
Mayon (Philippines) | 9 December-15 December 2009 | New Activity / Unrest Cite this Report
Mayon Eastern Philippine Volcanic Arc	According to news articles, PHIVOLCS reported that on 11 December an explosion from Mayon was detected by the seismic network. On 14 December, incandescence emanated from the lava dome in the summit crater and incandescent material traveled as far as 3 km down the S and SE flanks. At least five minor explosions were detected by the seismic network. Some local ashfall was reported. The Alert Level was raised to 3, prompting the order to evacuate about 50,000 people living within an 8-km radius from the base of the volcano. Sources: Inquirer.net, Philippine Daily Inquirer, The Manila Times
Piton de la Fournaise (France) | 9 December-15 December 2009 | New Activity / Unrest Cite this Report
Piton de la Fournaise Reunion Hotspot Volcano Group	OVPDLF reported that on 14 December an eruption from Piton de la Fournaise was preceded by a seismic crisis and summit deformation. Sub-parallel fissures along the rim of Dolomieu crater fed lava flows on the S slope. A third fissure that also produced lava flows opened on the E flank. The lava stopped flowing during the night, after a gradual decrease. On 15 December, gas was emitted from the S and SE fractures and low-intensity tremor was detected. Source: Observatoire Volcanologique du Piton de la Fournaise (OVPF)
Soufriere Hills (United Kingdom) | 9 December-15 December 2009 | New Activity / Unrest Cite this Report
Soufriere Hills Lesser Antilles Volcanic Arc	MVO reported that during 4-11 December activity from the Soufrière Hills lava dome continued at a high level and pyroclastic flow activity was concentrated on the N side. Pyroclastic flows traveled as far as 2 km NW into Tyers Ghaut and NE in abundance down Tuitt's Ghaut, and sometimes Whites Bottom Ghaut, continuing onto Farrell's plain. A few small pyroclastic flows also descended the Tar River valley to the E. On 10 December, a large seismic signal was associated with a relatively large pyroclastic flow in Tyers Ghaut that traveled 3.5 km, stopping just beyond the W end of Lee's village. The event prompted the National Disaster Preparedness and Response Advisory Committee (NDPRAC) to raise the Hazard Level to 4, restricting the hours residents can enter certain pre-designated hazard areas. Source: Montserrat Volcano Observatory (MVO)

Aira (Japan) | 9 December-15 December 2009 | Continuing ActivityCite this Report
Aira Ryukyu Volcanic Arc	Based on information from JMA, the Tokyo VAAC reported that explosions from Sakura-jima during 9-15 December produced plumes that rose to altitudes of 1.8-2.4 km (6,000-8,000 ft) a.s.l. and drifted NE, E, SE, and S. On 14 December, a pilot reported that an ash plume drifted S at an altitude of 2.7 km (9,000 ft) a.s.l. Source: Tokyo Volcanic Ash Advisory Center (VAAC)
Chaiten (Chile) | 9 December-15 December 2009 | Continuing ActivityCite this Report
Chaiten Southern Andean Volcanic Arc	Based on web camera views, the Buenos Aires VAAC reported that a steam-and-gas plume from Chaitén's lava-dome complex drifted SE on 12 December at altitudes of 1.5-2.1 km (5,000-7,000 ft) a.s.l. Source: Buenos Aires Volcanic Ash Advisory Center (VAAC)
Dukono (Indonesia) | 9 December-15 December 2009 | Continuing ActivityCite this Report
Dukono Halmahera Volcanic Arc	The Darwin VAAC reported that during 9-11 December ash plumes from Dukono rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted 90-130 km E and SE. Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Fuego (Guatemala) | 9 December-15 December 2009 | Continuing ActivityCite this Report
Fuego Central America Volcanic Arc	On 11, 14, and 15 December, INSIVUMEH reported that explosions from Fuego produced ash plumes that rose to altitudes of 4.1-4.7 km (13,500-15,400 ft) a.s.l. and drifted 8-12 km W and SW. Incandescence from the main crater and rumbling noises were noted. Avalanches descended the S and W flanks. Based on analyses of satellite imagery, the Washington VAAC reported that on 12 December a gas-and-ash plume drifted 20 km W. On 15 December, ashfall was reported in areas SW. Sources: Washington Volcanic Ash Advisory Center (VAAC), Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Karymsky (Russia) | 9 December-15 December 2009 | Continuing ActivityCite this Report
Karymsky Eastern Kamchatka Volcanic Arc	KVERT reported that analyses of satellite imagery revealed a thermal anomaly from Karymsky during 3 and 6-7 December; ash deposits extended 45 km SE on 6 December. A new lava flow was seen on the S flank on 8 December. Seismic data were seldom available due to technical problems. The Level of Aviation Color Code remained at Orange. Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Kilauea (United States) | 9 December-15 December 2009 | Continuing ActivityCite this Report
Kilauea Hawaiian-Emperor Hotspot Volcano Group	During 9-15 December, HVO reported that lava flowed SE from beneath Kilauea's Thanksgiving Eve Breakout (TEB) and rootless shield complex through a lava tube system, reaching the ocean at multiple locations between Waikupanaha and areas farther to the W. Towards the beginning of the reporting period, thermal anomalies detected by satellite and visual observations revealed occasional active lava flows. Incandescence was seen almost daily from Pu'u 'O'o crater. The vent in Halema'uma'u crater continued to produce an off-white plume that drifted predominantly to the SW, dropping small amounts of ash downwind. Incandescence originated from a few holes in the deep floor of the vent cavity. On 13 December, lava ponded on the floor, crusted over, and blocked the holes. Incandescence was again visible the next night. Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
Klyuchevskoy (Russia) | 9 December-15 December 2009 | Continuing ActivityCite this Report
Klyuchevskoy Eastern Kamchatka Volcanic Arc	KVERT reported that during 4-11 December seismic activity from Kliuchevskoi was above background levels and lava continued to flow down the ESE flank. Strombolian activity ejected tephra 200-300 m above the crater. Gas-and-steam plumes containing small amounts of ash rose to an altitude of 6.3 km (20,700 ft) a.s.l. and drifted E during 5-9 December. Satellite imagery revealed a large daily thermal anomaly at the volcano. The Level of Aviation Color Code remained at Orange. Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Manam (Papua New Guinea) | 9 December-15 December 2009 | Continuing ActivityCite this Report
Manam Bismarck Volcanic Arc	Based on analyses of satellite imagery, the Darwin VAAC reported that on 12 December an eruption from Manam produced a plume that rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted 75 km N. Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Nevado del Huila (Colombia) | 9 December-15 December 2009 | Continuing ActivityCite this Report
Nevado del Huila Northern Andean Volcanic Arc	Based on information from the Bogata MWO, the Washington VAAC reported that on 10 December an ash plume rose to an altitude of 7 km (23,000 ft) a.s.l. and drifted S. Ash was not identified in satellite imagery due to meteorological clouds in the area. INGEOMINAS reported that during 9-15 December seismic signals indicated occasional gas-and-ash emissions. White and bluish gas plumes seen on the web camera rose 2 km. Overflights revealed that the lava dome continued to grow and emit gases. Sources: Servicio Geológico Colombiano (SGC), Washington Volcanic Ash Advisory Center (VAAC)
Pacaya (Guatemala) | 9 December-15 December 2009 | Continuing ActivityCite this Report
Pacaya Central America Volcanic Arc	On 11, 14, and 15 December, INSIVUMEH reported that white and blue fumarolic plumes from Pacaya's MacKenney cone rose up 100 m and drifted S. Multiple lava flows on the S flank traveled 25-350 m. Incandescence from one of the inter-crater cones was noted. Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Rabaul (Papua New Guinea) | 9 December-15 December 2009 | Continuing ActivityCite this Report
Rabaul Bismarck Volcanic Arc	RVO reported that activity from Rabaul caldera's Tavurvur cone consisted of a few strong explosions towards the beginning of the 4-10 December reporting period, and emissions of gray ash afterwards. Diffuse white vapor was emitted during quieter intervals. Ash plumes rose 1 km above the summit and drifted SE towards Tokua and the Tokua airport, causing suspension of some flights. Based on analyses of satellite imagery, the Darwin VAAC reported that on 14 December an ash plume rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted 35 km SE. Sources: Rabaul Volcano Observatory (RVO), Darwin Volcanic Ash Advisory Centre (VAAC)
Santa Maria (Guatemala) | 9 December-15 December 2009 | Continuing ActivityCite this Report
Santa Maria Central America Volcanic Arc	On 11, 14, and 15 December, INSIVUMEH reported that explosions from Santa María's Santiaguito lava dome complex produced ash plumes that rose to altitudes of 2.8-3.5 km (9,200-11,500 ft) a.s.l. and drifted W and SW. Avalanches occasionally descended the SE flank of the dome. On 15 December, explosions generated pyroclastic flows that descended the E and SW flanks. Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Sheveluch (Russia) | 9 December-15 December 2009 | Continuing ActivityCite this Report
Sheveluch Eastern Kamchatka Volcanic Arc	KVERT reported that during 4-11 December seismic activity from Shiveluch was above background levels, possibly indicating ash plumes rising to an altitude of 5.5 km (18,000 ft) a.s.l. Fumarolic activity was seen with a video camera. Analyses of satellite imagery revealed a large daily thermal anomaly from the lava dome and an ash plume drifting 85 km SE on 6 December. The Level of Aviation Color Code remained at Orange. Based on information from KEMSD, the Tokyo VAAC reported that on 13 December an eruption produced a plume that rose to an altitude of 5.8 km (19,000 ft) a.s.l. Sources: Tokyo Volcanic Ash Advisory Center (VAAC), Kamchatkan Volcanic Eruption Response Team (KVERT)
Suwanosejima (Japan) | 9 December-15 December 2009 | Continuing ActivityCite this Report
Suwanosejima Ryukyu Volcanic Arc	Based on information from JMA, the Tokyo VAAC reported eruptions from Suwanose-jima on 14 and 15 December. Plumes rose to altitudes of 1.2-1.5 km (4,000-5,000 ft) a.s.l. and drifted E. Source: Tokyo Volcanic Ash Advisory Center (VAAC)

Weekly Reports Archive

Since the Weekly Volcanic Activity Report began in November 2000, there have been 20,652 individual reports over 1,244 weeks (average of 17 per week) on 338 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)