All times are local unless otherwise stated.

Lokon-Empung (Indonesia) | 5 December-11 December 2007 | New Activity / Unrest Cite this Report
Lokon-Empung Sangihe Volcanic Arc	CVGHM raised the Alert Level for Lokon-Empung from 2 to 3 (on a scale of 1-4) on 9 December based on visual observations, inflation detected by deformation instruments, and an increase in seismicity. The water in the Tompaluan crater changed color from green to gray and noises from degassing became stronger. White plumes rose from the crater to an altitude of 1.6 km (5,200 ft) a.s.l. Visitors and tourists were advised not to go within a 2-km radius of the crater. Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
Turrialba (Costa Rica) | 5 December-11 December 2007 | New Activity / Unrest Cite this Report
Turrialba Central America Volcanic Arc	OVSICORI-UNA reported that members of the media and local communities observed a gas-and-steam plume from Turrialba that rose to an altitude greater than 5.3 km (17,400 ft) a.s.l. on 5 December. Fieldwork confirmed an unusual output of gas from several fumaroles along the S outer wall. Areas burned by acute acidification have extended in the last month. Pastures turned yellowish near the upper areas, and native and exotic tree species were impacted as well as birch tree patches along most drainages. Within the W crater, temperatures of fumaroles reached 280 degrees Celsius and native sulfur was present. Source: Observatorio Vulcanologico y Sismologico de Costa Rica-Universidad Nacional (OVSICORI-UNA)

Anatahan (United States) | 5 December-11 December 2007 | Continuing ActivityCite this Report
Anatahan Mariana Volcanic Arc	Low-level tremor at Anatahan continued during 30 November-7 December. The Volcanic Alert Level remained at Advisory and the Aviation Color Code remained at Yellow. Source: Emergency Management Office of the Commonwealth of the Mariana Islands and United States Geological Survey Volcano Hazards Program
Arenal (Costa Rica) | 5 December-11 December 2007 | Continuing ActivityCite this Report
Arenal Central America Volcanic Arc	In November, activity originating from Arenal's Crater C consisted of gas emissions, sporadic Strombolian eruptions, lava flows traveling down the S flank, and occasional avalanches from lava-flow fronts. Blocks from near the edge of the crater rolled down the SE and SW flanks. Volcanic activity was at relatively low levels and few eruptions occurred. Acid rain and small amounts of ejected pyroclastic material affected the NE and SE flanks. Eruptions produced ash plumes that rose about 2.2 km (7,100 ft) a.s.l. Small avalanches of volcanic material traveled down several ravines. Crater D showed only fumarolic activity. Source: Observatorio Vulcanologico y Sismologico de Costa Rica-Universidad Nacional (OVSICORI-UNA)
Bagana (Papua New Guinea) | 5 December-11 December 2007 | Continuing ActivityCite this Report
Bagana Solomon Volcanic Arc	RVO reported that during 18 October-10 December white vapor plumes from Bagana were occasionally accompanied by ash plumes generated by rockfalls from the edges of the lava flow on the SE flank. Occasionally, booming and roaring noises were heard and incandescence at the summit was observed. Two explosions were accompanied by ash plumes on 19 and 27 November. Incandescent lava fragments were ejected from the summit on 7 and 9 December. On 9 December, an ash plume rose to an altitude of 2.8 km (9,200 ft) a.s.l. A lava flow became active and was continuously incandescent down the SE flank. Source: Rabaul Volcano Observatory (RVO)
Karymsky (Russia) | 5 December-11 December 2007 | Continuing ActivityCite this Report
Karymsky Eastern Kamchatka Volcanic Arc	KVERT reported that seismic activity at Karymsky was slightly above background levels during 30 November-7 December. A decrease in activity based on observations of satellite imagery during November and December 2007 prompted KVERT to lower the Level of Concern Color Code to Yellow on 7 December. Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Kilauea (United States) | 5 December-11 December 2007 | Continuing ActivityCite this Report
Kilauea Hawaiian-Emperor Hotspot Volcano Group	HVO reported that web camera views of fissure D from Kilauea's 21 July fissure eruption were mostly blocked by fog and fumes during 5-9 December. A brief view on 5 December revealed several overflows on the W side of Pond 1, a perched lava pond in the eruption channel formed by fissure D. A pilot report from an overflight on 6 December noted that all of the activity was close to fissure D and none of the SE Thanksgiving Eve breakout (TEB) flows traveled beyond 1.5 km. On 8 December, minor incandescence was observed in Pu'u 'O'o crater for the first time since 31 August, and was accompanied by a possible inflationary signal. Clear web camera views on 9 and 10 December revealed that the TEB shield continued to build vertically and was an estimated 15 m high. A few small earthquakes were located beneath the summit area and along the upper E rift zone and S-flank fault. Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
Rabaul (Papua New Guinea) | 5 December-11 December 2007 | Continuing ActivityCite this Report
Rabaul Bismarck Volcanic Arc	RVO reported on 10 December that after five weeks of low-level activity from Rabaul, ash was emitted from a new vent in the NE crater during 8-9 December. Resultant ash plumes rose to an altitude of 2.6 km (8,500 ft) a.s.l. and drifted S during 8-10 December. Occasional roaring noises were heard. Continuous incandescence from the lava dome on the crater floor was visible at night. Source: Rabaul Volcano Observatory (RVO)
Sheveluch (Russia) | 5 December-11 December 2007 | Continuing ActivityCite this Report
Sheveluch Eastern Kamchatka Volcanic Arc	KVERT reported that seismic activity at Shiveluch was above background levels during 30 November-7 December. Based on seismic interpretation, ash plumes rose to an altitude of 5.3 km (17,000 ft) a.s.l. and hot avalanches occurred. Visual observations and video footage analysis indicated that gas-and-steam plumes rose to altitudes of 4-5 km (13,100-16,400 ft) a.s.l. during the reporting period. One ash plume rose to an altitude of 5.7 km (18,700 ft) a.s.l. on 2 December. Based on observations of satellite imagery, a thermal anomaly was present in the crater every day during 30 November-7 December. The Level of Concern Color Code remained at Orange. Based on information from the KEMSD, the Tokyo VAAC reported that an eruption plume rose to an altitude of 5.2 km (17,000 ft) a.s.l. on 10 December. Sources: Kamchatkan Volcanic Eruption Response Team (KVERT), Tokyo Volcanic Ash Advisory Center (VAAC)
Soufriere Hills (United Kingdom) | 5 December-11 December 2007 | Continuing ActivityCite this Report
Soufriere Hills Lesser Antilles Volcanic Arc	MVO reported that during 3-7 December the lava dome at Soufrière Hills changed very little, based on visual observations. Seismic activity was very low and low-level rockfall activity continued. Fumarolic activity on the N and E flanks of the dome continued. The Alert Level remained elevated at 4 (on a scale of 0-5). Source: Montserrat Volcano Observatory (MVO)
St. Helens (United States) | 5 December-11 December 2007 | Continuing ActivityCite this Report
St. Helens High Cascades Volcanic Arc	Data from deformation-monitoring instruments indicated that during 5-11 December lava-dome growth at Mount St. Helens continued. Based on interpretations of flow-monitoring system data, lahars flowed out of the crater on 4 December, after a weather system passed through the region. Seismicity persisted at low levels, punctuated by M 1.5-2.5, and occasionally larger, earthquakes. Clouds occasionally inhibited visual observations. Source: US Geological Survey Cascades Volcano Observatory (CVO)
Suwanosejima (Japan) | 5 December-11 December 2007 | Continuing ActivityCite this Report
Suwanosejima Ryukyu Volcanic Arc	Based on information from JMA, the Tokyo VAAC reported that eruption plumes from Suwanose-jima rose to altitudes of 1.5-1.8 km (5,000-6,000 ft) a.s.l. on 10 December and drifted W. Ash was not visible on satellite imagery. Source: Tokyo Volcanic Ash Advisory Center (VAAC)
Tungurahua (Ecuador) | 5 December-11 December 2007 | Continuing ActivityCite this Report
Tungurahua Northern Andean Volcanic Arc	IG reported that although visual observations were occasionally limited due to cloud cover, ash-and-steam and ash plumes from Tungurahua rose to altitudes of 6-8 km (19,700-26,200 ft) a.s.l. during 5-11 December. Plumes drifted SW, W, and NW. During 5-8 December, incandescence at the summit was observed and roaring noises and "cannon shots" were heard. During 6-7 December, incandescent material was propelled out of the crater and rolled about 1 km down the flanks. Explosions shook the ground and rattled windows in multiple areas, including at the Tungurahua Observatory (OVT) in Guadalupe, 11 km N. During 5-8 December, ashfall was reported in areas to the SW, W, and NW. Source: Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN)
Ubinas (Peru) | 5 December-11 December 2007 | Continuing ActivityCite this Report
Ubinas Central Andean Volcanic Arc	Based on Significant Meteorological Information (SIGMET) advisories and pilot reports, the Buenos Aires VAAC reported that ash plumes from Ubinas rose to altitudes of 5.5-8.5 km (18,000-28,000 ft) a.s.l. and drifted N and NE during 4-7 and 10 December. Source: Buenos Aires 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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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)