All times are local unless otherwise stated.

Aira | 30 September-6 October 2009 | New Activity / Unrest Cite this Report
Aira Unknown	Based on information from JMA and pilot observations, the Tokyo VAAC reported that explosions from Sakura-jima during 30 September-6 October produced plumes that rose to altitudes of 1.8-4.3 km (6,000-14,000 ft) a.s.l. Plumes occasionally drifted E, N, and W. The JMA reported that explosions from Showa crater on 2 October ejected incandescent tephra 800 m away from the rim. On 3 October, Minami-dake crater exploded violently, producing an ash plume that rose 3 km above the crater. Ballistics were ejected 1.7 km away. The most recent previous explosion from the Minami-dake crater occurred on 22 February. Sources: Tokyo Volcanic Ash Advisory Center (VAAC), Japan Meteorological Agency (JMA)
Chaiten | 30 September-6 October 2009 | New Activity / Unrest Cite this Report
Chaiten Unknown	During 16-30 September, SERNAGEOMIN reported that Chaitén's Domo Nuevo 1 (Phase I) and Domo Nuevo 2 (Phase II) lava-dome complex continued to grow, generating block-and-ash flows from the collapse of unstable slopes. Gas plumes continued to rise from the complex and were visible using the web camera, S of the volcano. On 29 September, people living in Chaitén town, 10 km SW, noticed that the eruption column was larger. A dark area in the plume seen on the web camera was interpreted to possibly be from collapse of part of the lava dome to the SW. Scientists conducted an overflight and saw a third lava dome (Phase III) in the SW area of the complex, which had filled up a depression left by a collapse on 19 February. They also noted a NNW-trending depression along the center of the lava domes with spines at the N end, and that the central spine complex had disappeared. Ash-and-gas plumes that occasionally rose 2 km above the lava domes had two sources: one from the new dome and one from the central depression. Several parts of the depressions circling the lava domes had been filled in by collapsed material, and the depositional area near the mouth of the Blanco River had also grown. Based on web camera views, SIGMET notices, and analyses of satellite imagery, the Buenos Aires VAAC reported that on 30 September and 3 October diffuse ash plumes, possibly mixed with steam and gas, rose to an altitude of 2.4 km (8,000 ft) a.s.l. and drifted as far away as 55 km SE. Sources: Buenos Aires Volcanic Ash Advisory Center (VAAC), Servicio Nacional de Geología y Minería (SERNAGEOMIN)
Cleveland | 30 September-6 October 2009 | New Activity / Unrest Cite this Report
Cleveland Unknown	A small explosive eruption of Cleveland on 2 October prompted AVO to raise the Volcano Alert Level to Watch and the Aviation Color Code to Orange. A detached ash cloud at estimated altitudes of 4.6-6.1 km (15,000-20,000 ft) a.s.l. was seen on satellite imagery; the cloud drifted about 600 km NE and dispersed over the Bering Sea. No further activity was reported. On 5 October, the Volcano Alert Level was lowered to Advisory and the Aviation Color Code was lowered to Yellow. No seismic information was available because Cleveland does not have a real-time seismic network. Source: US Geological Survey Alaska Volcano Observatory (AVO)
Galeras | 30 September-6 October 2009 | New Activity / Unrest Cite this Report
Galeras Unknown	An explosive eruption from Galeras on 30 September prompted INGEOMINAS to raise the Alert Level to I (Red; "imminent eruption or in progress"). National Park personnel reported two explosions and incandescent material ejected from the area of the active cone. An ash plume rose to an approximate altitude of 12.3 km (40,400 ft) a.s.l. and drifted E, then N. The sulfur dioxide emission rate was between 1,100 and 9,300 tons per day. Ash was deposited in Sandoná (15 km NW), and Ancuya, Linares, and Sotomayor (40 km NW). Seismicity decreased after the eruption. On 1 October, seismicity was low and the sulfur dioxide emission rate was 300 tons per day. The Alert Level was lowered to II (Orange; "probable eruption in term of days or weeks"), and then to III (Yellow; "changes in the behavior of volcanic activity") on 6 October. Source: Servicio Geológico Colombiano (SGC)
Gaua | 30 September-6 October 2009 | New Activity / Unrest Cite this Report
Gaua Unknown	According to news articles from 2 October, increased seismicity at Gaua was detected during the previous two weeks. Villagers living nearby reported ashfall and sulfur odors. Both villagers and a pilot flying past Gaua heard explosions. The Alert Level was raised to 1 (on a scale of 0-5). Source: Radio Australia
Karymsky | 30 September-6 October 2009 | New Activity / Unrest Cite this Report
Karymsky Unknown	KVERT reported that seismic activity at Karymsky was elevated above background levels during 25 September-2 October and possibly indicated weak ash explosions. Analyses of satellite imagery revealed a weak thermal anomaly over the lava dome on 28 September; cloud cover prevented observations on the other days. Scientists saw fumarolic activity during an overflight on 1 October. The Level of Aviation Color Code remained at Orange. Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Klyuchevskoy | 30 September-6 October 2009 | New Activity / Unrest Cite this Report
Klyuchevskoy Unknown	KVERT reported that during 25 September-2 October seismic activity from Kliuchevskoi was slightly above background levels and weak tremor was detected. Satellite imagery revealed a weak thermal anomaly over the volcano. Strombolian activity ejected tephra 70-100 m above the crater during 28-30 September. The Level of Aviation Color Code remained at Yellow. Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Sheveluch | 30 September-6 October 2009 | New Activity / Unrest Cite this Report
Sheveluch Unknown	KVERT reported that during 25 September-2 October seismic activity from Shiveluch was above background levels. Analyses of satellite imagery revealed a large daily thermal anomaly over the lava dome. Fumarolic activity was occasionally seen. Based on interpretations of seismic data, ash plumes possibly rose to an altitude of 7 km (23,000 ft) a.s.l. on 27 September and to an altitude of 4.5 km (14,800 ft) a.s.l. on other days. According to video camera data and visual observations, ash plumes rose to an altitude of 4 km (13,100 ft) a.s.l. on 28 September. An ash plume was seen on satellite imagery drifting 65 km ESE on 29 September. The Level of Aviation Color Code remained at Orange. Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Soufriere Hills | 30 September-6 October 2009 | New Activity / Unrest Cite this Report
Soufriere Hills Unknown	MVO reported that a short volcano-tectonic earthquake swarm from Soufrière Hills lava dome was detected at 2100 on 4 October. A period of tremor and vigorous ash venting followed about an hour later. The resulting ash plume drifted WNW across the island and out to sea, causing ashfall in Old Towne and Olveston. The seismic signals indicated no explosive activity or pyroclastic flows, but only two rockfalls after the ash-venting event. During midnight to 0600 on 5 October, intermittent ash venting produced ash plumes that drifted WNW. Two more "ash venting" events occurred at 1035 and 1325, without precursory seismicity, producing ash plumes that rose to altitudes of 3-4.6 km (10,000-15,000 ft) a.s.l. Ash fell S of inhabited areas. Based on information from MVO and analyses of satellite imagery, the Washington VAAC reported that on 6 October several ash clouds rose to altitudes of 3.7-5.5 km (12,000-18,000 ft) a.s.l. and drifted W. Sources: Montserrat Volcano Observatory (MVO), Washington Volcanic Ash Advisory Center (VAAC)

Batu Tara | 30 September-6 October 2009 | Continuing ActivityCite this Report
Batu Tara Unknown	Based on analyses of satellite imagery, the Darwin VAAC reported that during 30 September-3 October and 5-6 October ash plumes from Batu Tara rose to an altitude of 2.4 km (8,000 ft) a.s.l. and drifted 25-75 km W, NW, and N. Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Dukono | 30 September-6 October 2009 | Continuing ActivityCite this Report
Dukono Unknown	Based on analyses of satellite imagery, the Darwin VAAC reported that on 2 October an ash plume from Dukono rose to an altitude of 2.7 km (9,000 ft) a.s.l. and drifted 75 km NE. On 6 October, an ash plume rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted 55 km NE. Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Kilauea | 30 September-6 October 2009 | Continuing ActivityCite this Report
Kilauea Unknown	During 30 September-6 October, HVO reported that lava flowed SE from underneath Kilauea's Thanksgiving Eve Breakout (TEB) and rootless shield complex through a lava tube system, reaching the Waikupanaha ocean entry. Thermal anomalies detected in satellite images revealed active surface lava flows on top of the pali. The vent in Halema'uma'u crater continued to produce a diffuse white plume that drifted SW. Small amounts of occasional fresh ash were retrieved from collection bins placed near the plume. During 30 September and 2, 4, and 5 October, a lava pond within the vent, about 200 m below the Halema'uma'u crater floor, rose and fell, circulated, and weakly spattered. Preliminary measurements indicated that the sulfur dioxide emission rate at the summit remained elevated; 410, 650, and 480 tonnes per day were measured on 30 September, 1 and 2 October, respectively. The 2003-2007 average rate was 140 tonnes per day. Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
Langila | 30 September-6 October 2009 | Continuing ActivityCite this Report
Langila Unknown	Based on analyses of satellite imagery, the Darwin VAAC reported that on 30 September an ash plume from Langila drifted 260 km NW at an altitude of 4.3 km (14,000 ft) a.s.l. On 5 October, a diffuse ash plume rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted 185 km N. Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Popocatepetl | 30 September-6 October 2009 | Continuing ActivityCite this Report
Popocatepetl Unknown	CENAPRED reported that during 3-6 October emissions of steam and gas from Popocatépetl contained slight amounts of ash. Source: Centro Nacional de Prevencion de Desastres (CENAPRED)
Rabaul | 30 September-6 October 2009 | Continuing ActivityCite this Report
Rabaul Unknown	RVO reported that during 25 September-1 October gray ash plumes from Rabaul caldera's Tavurvur cone rose 2 km above the crater. Ashfall was reported in Rabaul town (3-5 km NW) and surrounding areas. Occasionally, incandescence from the summit crater was seen at night and incandescent lava fragments were ejected from the crater. Based on analyses of satellite imagery, the Darwin VAAC reported that on 6 October an ash plume rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted 55 km NW. Sources: Rabaul Volcano Observatory (RVO), Darwin Volcanic Ash Advisory Centre (VAAC)
Reventador | 30 September-6 October 2009 | Continuing ActivityCite this Report
Reventador Unknown	Based on information from IG, the Washington VAAC reported that on 4 October an ash plume from Reventador drifted W. Ash was not seen in satellite imagery, although meteorological clouds were present. An occasional thermal anomaly was seen, however. Source: Washington Volcanic Ash Advisory Center (VAAC)
Sangay | 30 September-6 October 2009 | Continuing ActivityCite this Report
Sangay Unknown	The Washington VAAC reported that on 4 October a pilot saw an ash plume from Sangay drifting W at altitudes of 5.2-7.6 km (17,000-25,000 ft) a.s.l. Meteorological clouds prevented satellite views of the area. No additional reports of the ash plume were received by the VAAC. Source: Washington Volcanic Ash Advisory Center (VAAC)
Suwanosejima | 30 September-6 October 2009 | Continuing ActivityCite this Report
Suwanosejima Unknown	Based on information from JMA, the Tokyo VAAC reported explosions from Suwanose-jima on 1 October. A plume rose to an altitude of 1.5 km (5,000 ft) a.s.l. and rifted W. Source: Tokyo Volcanic Ash Advisory Center (VAAC)

Weekly Reports Archive

Since the Weekly Volcanic Activity Report began in November 2000, there have been 20,140 individual reports over 1,221 weeks (average of 16 per week) on 334 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)