All times are local unless otherwise stated.

Cleveland | 4 April-10 April 2012 | New Activity / Unrest Cite this Report
Cleveland Chuginadak Island (USA)	AVO reported that a small explosion from Cleveland was detected at 0112 on 4 April by distant seismic stations and infrasound arrays. Weather conditions prevented the detection of a possible eruption cloud in satellite images or by visual observation of the summit. Observations the next day revealed a thermal anomaly and that the 70-m-diameter lava dome had been destroyed by the explosion. This was the third lava dome that was erupted and subsequently destroyed by explosive events since the eruption began in July 2011. On 6 April two short-duration explosions occurred at about 1635 and 2126. The resulting eruption clouds were ash poor and did not rise above 3 km (10,000 ft) a.s.l. Elevated surface temperatures were observed using infrared satellite images near the times of the explosions. Satellite observations were obscured by clouds during 8-10 April. No seismic information was available because Cleveland does not have a real-time seismic network. Source: US Geological Survey Alaska Volcano Observatory (AVO)
Fuego | 4 April-10 April 2012 | New Activity / Unrest Cite this Report
Fuego South-Central Guatemala	INSIVUMEH reported that during 9-10 April explosions from Fuego produced ash plumes that rose 100-900 m above the crater and drifted 10-15 km E and SE. Explosions produced shock waves detected within 8 km of the volcano. Avalanches descended the flanks. Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Nevado del Ruiz | 4 April-10 April 2012 | New Activity / Unrest Cite this Report
Nevado del Ruiz Colombia	According to INGEOMINAS, the Observatorio Vulcanológico and Sismológico de Manizales reported that during 4-10 April seismicity at Nevado del Ruiz fluctuated but remained elevated. Sulfur dioxide emissions also remained high; occasionally a sulfur odor was reported in Manizales, about 25 km NW. On 5 April a volcano-tectonic earthquake, M 2.8, occurred below Arenas crater at a depth of 1 km, and was the highest magnitude earthquake recorded since February. During 4-6 April gas-and-steam plumes drifted NW. Gas-and-steam plumes rose 3 km above the crater on 7 April and 1.5 km above the crater on 10 April; the plumes drifted SE both days. The Alert Level remained at II (Orange; "eruption likely within days or weeks"). Source: Servicio Geológico Colombiano (SGC)
Soufriere Hills | 4 April-10 April 2012 | New Activity / Unrest Cite this Report
Soufriere Hills Montserrat	MVO reported that during 30 March-6 April activity at the Soufrière Hills lava dome was generally at a low level and no ash-venting episodes had been detected since 23 March. The average sulfur dioxide emission rate measured during the week was 529 tonnes per day with a minimum of 200 and a maximum of 1,033. Scientists aboard a helicopter overflight on 4 April observed a new vent which had formed on 23 March; it was 30-50 m across and on the W side of the crater floor. The Hazard Level remained at 2. Source: Montserrat Volcano Observatory (MVO)

Karymsky | 4 April-10 April 2012 | Continuing ActivityCite this Report
Karymsky Eastern Kamchatka (Russia)	KVERT reported that during 30 March-6 April moderate seismic activity from Karymsky continued to be detected, and indicated that possible ash plumes rose to an altitude of 2.5 km (8,200 ft) a.s.l. Satellite imagery showed a thermal anomaly on the volcano on 29 March. The Aviation Color Code remained at Orange. Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Kilauea | 4 April-10 April 2012 | Continuing ActivityCite this Report
Kilauea Hawaiian Islands (USA)	During 4-10 April HVO reported that the circulating lava lake 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. Incandescence was visible from both a lava pond in a small pit on the E edge and a small spatter cone on the SE edge of the Pu'u 'O'o crater floor, and on the upper part of the lava-tube system on the E flank. Lava flows continued to advance down the pali and across the coastal plain, reaching about 1.6 km from the coast. During 6-9 April a small lava flow issued three times from a vent on the SE edge of the Pu'u 'O'o crater floor. The first two flows advanced N almost the entire width of the floor. Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
Pagan | 4 April-10 April 2012 | Continuing ActivityCite this Report
Pagan Mariana Islands (USA)	Clear-to-partly-cloudy satellite images of Pagan showed a gas-and-steam plume extending downwind from the summit vent during 30 March-6 April. The Aviation Color Code remained at Yellow and the Volcano Alert Level remained at Advisory. According to the Washington VAAC a pilot observed a plume containing a small amount of ash that rose to an altitude below 1.5 km (5,000 ft) a.s.l. on 7 April. Satellite imagery showed a gas-and-steam plume, with possible ash content, drifting 204 km SSW. Sources: Washington Volcanic Ash Advisory Center (VAAC), Emergency Management Office of the Commonwealth of the Mariana Islands and United States Geological Survey Volcano Hazards Program
Puyehue-Cordon Caulle | 4 April-10 April 2012 | Continuing ActivityCite this Report
Puyehue-Cordon Caulle Central Chile	OVDAS-SERNAGEOMIN reported that during 9-10 April satellite and web camera observations of the Cordón Caulle rift zone, part of the Puyehue-Cordón Caulle volcanic complex, showed plumes that rose no higher than 450 m above the crater. Incandescence from the crater was also observed. The Alert Level remained at Orange. Source: Servicio Nacional de Geología y Minería (SERNAGEOMIN)
Ranakah | 4 April-10 April 2012 | Continuing ActivityCite this Report
Ranakah Flores Island	CVGHM reported that during January-8 April white plumes rose 10-15 m above the Anak Ranakah lava dome and seismicity decreased. On 9 April the Alert Level was lowered to 1 (on a scale of 1-4). Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
Santa Maria | 4 April-10 April 2012 | Continuing ActivityCite this Report
Santa Maria Southwestern Guatemala	Based on analyses of satellite imagery and reports from INSIVUMEH, the Washington VAAC reported that on 7 April multiple ash clouds from explosions at Santa María drifted 37 km SW and 11 km S. INSIVUMEH reported that during 8-10 April explosions from Caliente dome generated ash plumes that rose 600-900 m above the dome and drifted 15 km S and SW. Lava flows continued to produce avalanches that descended the flanks. Sources: Washington Volcanic Ash Advisory Center (VAAC), Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Sheveluch | 4 April-10 April 2012 | Continuing ActivityCite this Report
Sheveluch Central Kamchatka (Russia)	KVERT reported that explosive activity at Shiveluch continued during 29 March-6 April. Ground-based observers and satellite imagery indicated that a viscous lava flow continued to effuse in the crater formed during a 2010 eruption. Visual observations revealed that ash plumes rose to an altitude of 4 km (13,100 ft) a.s.l. on 30 March and 3 April. Seismic data indicated that ash plumes potentially rose to an altitude of 6.6 km (21,600 ft) a.s.l. every day. Satellite imagery showed a weak thermal anomaly on the lava dome during 29-31 March and 3 April, and ash plumes that drifted 114 km W, E, and NE during 29-30 March and 3 April. The Aviation Color Code remained at Orange. Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Tambora | 4 April-10 April 2012 | Continuing ActivityCite this Report
Tambora Sumbawa Island	CVGHM reported that during January-8 April plumes did not rise from Tambora, no changes were observed around the caldera, and seismicity decreased. On 9 April the Alert Level was lowered to 1 (on a scale of 1-4). Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
Tungurahua | 4 April-10 April 2012 | Continuing ActivityCite this Report
Tungurahua Ecuador	IG reported that during 4-8 April visual observations of Tungurahua were limited due to cloud cover. During 9-10 April ash-and-steam plumes rose 2-3 km above the crater and drifted from NE to SE. Explosions were heard in areas near the volcano. Ashfall was reported in Capil, Palictahua, and Los Toctes on 9 April. Lahars descended the W flank on 10 April and caused the road between Baños and Penipe to close. Source: Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN)

Weekly Reports Archive

Since the Weekly Volcanic Activity Report began in November 2000, there have been 20,019 individual reports over 1,216 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)