All times are local unless otherwise stated.

Gaua (Vanuatu) | 5 October-11 October 2011 | New Activity / Unrest Cite this Report
Gaua Vanuatu Volcanic Arc	Vanuatu Geohazards Observatory reported that the seismic network monitoring Gaua detected volcanic activity in August. Gas plumes were detected by the OMI satellite on 17, 27, and 28 September, and ashfall was reported in the N, E, and W parts of Gaua on 10 October by local authorities. The Alert Level remained at 1 (on a scale of 0-4). Source: Vanuatu Meteorology and Geohazards Department (VMGD)
Hierro (Spain) | 5 October-11 October 2011 | New Activity / Unrest Cite this Report
Hierro Canary Volcanic Province	Instituto Geográfico Nacional (IGN) reported more than 700 new seismic events were detected at Hierro during 4-11 October, 52 of them were felt by residents. A M 4.3 earthquake was detected on 8 October, located 1.5 km from the SW coast of the island at 14 km depth. Following the event, the trend of the superficial deformation changed, suggesting deflation of the system. During the night of 8 October through the following day, low-magnitude seismic events occurred at depths of less than 2 km. Since 0515 on 10 October volcanic tremor was clearly recorded by all of the seismic stations on the island, with highest amplitudes recorded in the southernmost station. All data suggested a submarine eruption. On 11 October at about 0700 the amplitude of the tremor increased. During that morning residents on the S of the island reported feeling vibrations. After midday, the Government of the Canary Islands raised the Alert Code to Red for Restinga village (at the southernmost point of Hierro) and evacuated the residents. A maritime exclusion zone extended about 4 nautical miles from Restinga. Source: Instituto Geográfico Nacional (IGN)
Krakatau (Indonesia) | 5 October-11 October 2011 | New Activity / Unrest Cite this Report
Krakatau Sunda Volcanic Arc	On 8 October, a news article stated that activity at Anak Krakatau was increasing; the number of seismic events was 5,204 on 6 October, 5,543 on 7 October, and 5,883 on 8 October. The Alert Level remained at 3 (on a scale of 1-4), and visitors and residents were not permitted to approach the volcano within a 2-km radius. Source: The Jakarta Post
Sangay (Ecuador) | 5 October-11 October 2011 | New Activity / Unrest Cite this Report
Sangay Northern Andean Volcanic Arc	Based on information from the Guayaquil MWO and a pilot observation, the Washington VAAC reported that on 11 October an ash plume from Sangay from a possible eruption rose to an altitude of 6.7 km (22,000 ft) a.s.l. and drifted W. Ash was not observed in satellite imagery. Source: Washington Volcanic Ash Advisory Center (VAAC)
Sheveluch (Russia) | 5 October-11 October 2011 | New Activity / Unrest Cite this Report
Sheveluch Eastern Kamchatka Volcanic Arc	KVERT reported that seismic activity at Shiveluch was moderate during 30 September-7 October. Ash plumes rose to altitudes of 6-9 km (19,700-30,000 ft) a.s.l. during 3-5 October, followed by new lava-dome extrusion. Seismicity indicated that possible ash plumes rose to altitudes of 4.5-5 km (14,800-16,400 ft) a.s.l. during 5-6 October; ground-based observers noted that ash plumes rose to an altitude of 5 km (16,400 ft) a.s.l. on those same days. Satellite imagery showed a large and bright thermal anomaly on the lava dome on 5 October and ash plumes that drifted 100 km NE on 6 October. The Aviation Color Code was lowered to Orange. Based on information from KEMSD, the Tokyo VAAC reported that on 8 October an eruption produced a plume that rose to an altitude of 7 km (23,000 ft) a.s.l. and drifted E. Subsequent satellite images that day showed that ash was present and then had dissipated. An eruption on 10 October produced a plume that rose to an altitude of 7.3 km (24,000 ft) a.s.l. Sources: Kamchatkan Volcanic Eruption Response Team (KVERT), Tokyo Volcanic Ash Advisory Center (VAAC)
Tungurahua (Ecuador) | 5 October-11 October 2011 | New Activity / Unrest Cite this Report
Tungurahua Northern Andean Volcanic Arc	Based on information from IG, the Washington VAAC reported that on 7 October an ash plume from Tungurahua rose to an altitude of 6.1 km (20,000 ft) a.s.l. and drifted W. Ash was not observed in satellite imagery. [A 9 November VAAC report stated that IG noted no ash emissions from Tungurahua since June.] Source: Washington Volcanic Ash Advisory Center (VAAC)

Aira (Japan) | 5 October-11 October 2011 | Continuing ActivityCite this Report
Aira Ryukyu Volcanic Arc	Based on information from JMA, the Tokyo VAAC reported that during 5-11 October explosions from Sakura-jima produced plumes that rose to altitudes of 1.2-3 km (4,000-10,000 ft) a.s.l. and drifted NW, N, SE, and S. During 6-8 October pilots observed ash plumes that rose to altitudes of 1.8-3.7 km (6,000-12,000 ft) a.s.l. Source: Tokyo Volcanic Ash Advisory Center (VAAC)
Bagana (Papua New Guinea) | 5 October-11 October 2011 | Continuing ActivityCite this Report
Bagana Solomon Volcanic Arc	Based on analyses of satellite imagery, the Darwin VAAC reported that during 8-9 October ash plumes from Bagana rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted 45-55 km E and NW. Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Cleveland (United States) | 5 October-11 October 2011 | Continuing ActivityCite this Report
Cleveland Aleutian Ridge Volcanic Arc	AVO reported that during 5-6 and 9-11 October cloud cover over Cleveland prevented views of the lava dome in the summit crater. Partly cloudy satellite views during 7-8 October showed elevated surface temperatures at the summit. The Volcano Alert Level remained at Watch and the Aviation Color Code remained at Orange. No current seismic information was available because Cleveland does not have a real-time seismic network. Source: US Geological Survey Alaska Volcano Observatory (AVO)
Dukono (Indonesia) | 5 October-11 October 2011 | Continuing ActivityCite this Report
Dukono Halmahera Volcanic Arc	Based on analyses of satellite imagery, the Darwin VAAC reported that during 5-6 and 8-9 October ash plumes from Dukono rose to altitudes of 2.1-2.4 km (7,000-8,000 ft) a.s.l. and drifted 75-83 km NE and SE. Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Etna (Italy) | 5 October-11 October 2011 | Continuing ActivityCite this Report
Etna Sicily Volcanic Province	Sezione di Catania - Osservatorio Etneo reported that the sixteenth paroxysmal eruptive episode of 2011 took place at the New SE Crater (New SEC) of Etna during the afternoon of 8 October. A rapid increase in volcanic tremor amplitude was detected that morning, and at about 1300 weak and discontinuous Strombolian explosions were recorded by surveillance cameras. Two hours later, lava flowed from a deep notch in the SE rim of the crater. At around 1545 vigorous Strombolian activity was observed from numerous vents along a short fissure on the SE flank of the cone, which had first been active during the 29 August paroxysm (the twelfth). Weather conditions deteriorated at about 1615, preventing direct observations of the Strombolian activity changing into sustained lava fountaining and ash emissions. However, this change was audible around 1630, and a dense ash-and-vapor plume rapidly rose above the weather clouds and drifted E. At the same time lava flows descended on the W slope of the Valle del Bove. Eruptive vents opened on the NE flank of the cone, approximately along the fracture that first opened during 8 September, and two small lava flows were emitted. The more voluminous lava flow traveled a few hundred meters downslope. The paroxysmal phase lasted a little longer than 20 minutes and ended around 1650. Ash emissions continued until 1945, when the volcanic tremor amplitude returned to levels similar to those preceding the paroxysmal episode, and the lava flow fronts appeared to stagnate. The ash cloud drifted ENE and produced ash- and lapilli-fall in a narrow sector from the Ripe della Naca area and the village of Puntalazzo (13 km E) to the town of Mascali (18 km E). Source: Sezione di Catania - Osservatorio Etneo (INGV)
Karymsky (Russia) | 5 October-11 October 2011 | Continuing ActivityCite this Report
Karymsky Eastern Kamchatka Volcanic Arc	KVERT reported that seismic activity continued at a moderate level at Karymsky during 30 September-7 October and indicated that possible ash plumes rose to an altitude of 3.2 km (10,500 ft) a.s.l. Satellite imagery showed a thermal anomaly on the volcano during 4-5 October. The Aviation Color Code remained at Orange. Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Kilauea (United States) | 5 October-11 October 2011 | Continuing ActivityCite this Report
Kilauea Hawaiian-Emperor Hotspot Volcano Group	During 5-11 October, HVO reported that the lava lake circulated and periodically rose and fell in the deep pit within Kilauea's Halema'uma'u crater. Almost daily measurements indicated that the gas plume from the vent continued to deposit variable amounts of ash and occasionally fresh spatter nearby. At the E rift zone, the fissure that formed on 21 September on the upper E flank of Pu'u 'O'o continued to feed slowly-advancing lava flows to the NE and SE of the fissure. During the beginning of the week, overall activity within and SE of Pu'u 'O'o Crater had slowed; only a few lava patches were visible in webcams. During 7-8 October lava began to flow from a vent at the E end of the crater floor and from an area at the W end the next day. Lava flows from the E-end source stalled on 10 October. Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
Kizimen (Russia) | 5 October-11 October 2011 | Continuing ActivityCite this Report
Kizimen Eastern Kamchatka Volcanic Arc	KVERT reported that during 30 September-7 October video data showed that a large lava flow on Kizimen's NE flank continued to effuse. Strong fumarolic activity was observed during 29-30 September and 3-6 October. A thermal anomaly on the volcano was detected daily in satellite images but the temperature of the anomaly decreased during the end of the week. During 5-6 October the number of volcanic earthquakes decreased, from 1,300 to 500-700, as well as the magnitudes. The Aviation Color Code remained at Orange. Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Lokon-Empung (Indonesia) | 5 October-11 October 2011 | Continuing ActivityCite this Report
Lokon-Empung Sangihe Volcanic Arc	CVGHM reported that on 10 October white and gray plumes rose 100-300 m above Tompaluan crater, in the saddle between the Lokon-Empung peaks. Based on information from CVGHM, the Darwin VAAC reported that on 11 October an ash plume rose to an altitude of 2.1 km (7,000 ft) a.s.l. The Alert Level remained at 3 (on a scale of 1-4). Sources: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM), Darwin Volcanic Ash Advisory Centre (VAAC)
Marapi (Indonesia) | 5 October-11 October 2011 | Continuing ActivityCite this Report
Marapi Sunda Volcanic Arc	Based on a pilot report, the Darwin VAAC reported that on 11 October an ash plume from Marapi rose to an altitude of 3.7 km (12,000 ft) a.s.l. Ash was not identified in satellite imagery. Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Puyehue-Cordon Caulle (Chile) | 5 October-11 October 2011 | Continuing ActivityCite this Report
Puyehue-Cordon Caulle Southern Andean Volcanic Arc	Based on seismicity during 5-10 October, OVDAS-SERNAGEOMIN reported that the eruption from the Cordón Caulle rift zone, part of the Puyehue-Cordón Caulle volcanic complex, continued at a low level. Plumes visible with an area web camera rose no higher than 4 km above the crater during 5-7 October and were observed in satellite imagery drifting 30-60 km SE, SW, and N. On 9 October a white plume observed with the camera rose 4 km above the crater. Satellite imagery that day showed a widely dispersed ash plume drifting E. On 10 October a plume that was mostly white, but occasionally gray, rose 3.5 km above the crater. The Alert Level remained at Red. Source: Servicio Nacional de Geología y Minería (SERNAGEOMIN)

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.

Some of the documents on this server may contain live references (or pointers) to information created and maintained by other organizations. Please note that USGS does not control and cannot guarantee the relevance, timeliness, or accuracy of these outside materials.

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)