All times are local unless otherwise stated.

Merapi (Indonesia) | 10 May-16 May 2006 | New Activity / Unrest Cite this Report

Merapi Sunda Volcanic Arc

CVGHM reported that on 11 May, gas plumes rose to ~600 m above Merapi (or 11,600 ft a.s.l.). Avalanches of incandescent material extended 200 m SE towards the Gendol River, and 1.5 km SW towards the Krasak River. Several small incandescent avalanches of volcanic material were visible from observatory posts. The new lava dome at the volcano's summit had grown to fill the gap between the 2001 lava flows and the 1997 lava flows on the W side of the summit. The lava dome reached a height above that of the 1997 lava flows. Seismicity was dominated by multi-phase earthquakes and signals associated with avalanches. On 13 May at 0940, the Alert Level was raised from 3 to 4, the highest level. The Darwin VAAC reported that on 11 May an ash plume was visible on satellite imagery below 3.7 km (12,000 ft) a.s.l. An ash plume at an unknown height was visible on satellite imagery on 15 May. According to news reports, after the Alert Level was raised to 4 on 13 May, about 4,500 people living near the volcano were evacuated. Intense activity occurred on 15 May, with pyroclastic flows traveling as far as 4 km to the W. By 16 May a total of about 22,000 people were evacuated; according to figures posted at the district disaster task force center about 16,870 people were evacuated from three districts in Central Java Province, and more than 5,600 others were evacuated from the Slemen district, a part of Yogyakarta Province. Activity decreased on 16 May. On 17 May pyroclastic flows traveled as far as 3 km. Local volcanologists reported that the lava dome continued to grow, but at a slower rate than during previous days. Sources: Darwin Volcanic Ash Advisory Centre (VAAC), Agence France-Presse (AFP), Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM), Associated Press, Reuters

Arenal (Costa Rica) | 10 May-16 May 2006 | Continuing ActivityCite this Report
Arenal Central America Volcanic Arc	On 10 May around 1000, a pyroclastic flow traveled down Arenal's N flank. An ash-and-gas cloud was produced that drifted SW. Source: Observatorio Vulcanologico y Sismologico de Costa Rica-Universidad Nacional (OVSICORI-UNA)
Bezymianny (Russia) | 10 May-16 May 2006 | Continuing ActivityCite this Report
Bezymianny Eastern Kamchatka Volcanic Arc	Following an explosive eruption at Bezymianny on 9 May, seismicity was at background levels on 10 May. In addition, fumarolic plumes were observed and lava flows probably extended from the lava dome. On 11 May the Concern Color Code at Bezymianny was reduced from Orange to Yellow. On 12 May, seismicity remained at background levels and gas-and-steam plumes were visible. Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Galeras (Colombia) | 10 May-16 May 2006 | Continuing ActivityCite this Report
Galeras Northern Andean Volcanic Arc	INGEOMINAS reported that during 9-15 May, a partially solidified lava dome remained in Galeras' main crater. Seismicity and the sulfur-dioxide flux continued at low levels. Gas and sporadic ash emissions rose to low levels. Galeras remained at Alert Level 2 (likely eruption in days or weeks). Source: Servicio Geológico Colombiano (SGC)
Karymsky (Russia) | 10 May-16 May 2006 | Continuing ActivityCite this Report
Karymsky Eastern Kamchatka Volcanic Arc	During 5-12 May, eruptive activity continued at Karymsky. Based on interpretations of seismic data, ash plumes rose to a height of ~5.3 km (17,400 ft) a.s.l. A thermal anomaly was present on satellite data when the crater was visible. Ash plumes drifted SE. KVERT warned that activity from the volcano could affect nearby low-flying aircraft. Karymsky remained at Concern Color Code Orange. Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Kilauea (United States) | 10 May-16 May 2006 | Continuing ActivityCite this Report
Kilauea Hawaiian-Emperor Hotspot Volcano Group	During 15-16 May, lava from Kilauea continued to flow off of a lava delta into the ocean at the East Lae`apuki entry. No surface lava flows were visible on the Puluma pali fault scarp, as has been the case since 8 February. Kilauea's summit began to deflate on 14 May. On 16 May, inflation occurred that was accompanied by an abrupt drop in volcanic tremor at Kilauea's summit. Volcanic tremor reached moderate levels at Pu`u `O`o. Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
Lopevi (Vanuatu) | 10 May-16 May 2006 | Continuing ActivityCite this Report
Lopevi Vanuatu Volcanic Arc	The Wellington VAAC reported that a slow moving plume from Lopevi reached a height of 3 km (10,000 ft) a.s.l. on 10 May. On 11 May, a plume rose to 4.6 km (15,000 ft) a.s.l. and trended SE. During 12-13 May, the plume height lessened to 3 km (10,000 ft) a.s.l. as the eruption vigor reportedly decreased. According to Vanuatu's National Disaster Office, a news article reported that on 15 May an eruption at Lopevi produced heavy ashfall extending to the neighboring islands of Ambrym and Paama. Source: Wellington Volcanic Ash Advisory Center (VAAC)
Semeru (Indonesia) | 10 May-16 May 2006 | Continuing ActivityCite this Report
Semeru Sunda Volcanic Arc	An ash plume from Semeru at a height of 6.1 km (20,000 ft) a.s.l. was observed on satellite imagery. Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Soufriere Hills (United Kingdom) | 10 May-16 May 2006 | Continuing ActivityCite this Report
Soufriere Hills Lesser Antilles Volcanic Arc	During 5-12 May, the new lobe of the lava dome at Soufrière Hills that developed towards the S produced rockfalls that predominantly extended from the W to the SE. On the 12th, the lava dome volume was approximately 80 million cubic meters, having grown at an average rate of 8 cubic meters per second through April. Seismicity typical of this current growth phase was dominated by rockfall activity during the report period. The average sulfur-dioxide flux during the week was 702 metric tons per day. Sources: Washington Volcanic Ash Advisory Center (VAAC), Montserrat Volcano Observatory (MVO)
St. Helens (United States) | 10 May-16 May 2006 | Continuing ActivityCite this Report
St. Helens High Cascades Volcanic Arc	Analysis of photographs revealed that a slab of rock approximately 50,000 cubic meters in volume was shed from the N margin of the growing spine at Mt. St. Helens sometime during 6-7 May. This activity probably coincided with a large seismic signal recorded on the night of 7 May. Rock-avalanche deposits extended a few hundred meters to the NE. The avalanche was accompanied by an ash cloud. The spine continued to grow during 10-15 May, producing rockfalls that intensified on the evening of 14 May. Incandescence was visible on satellite imagery. The volcano remained at Volcano Advisory (Alert Level 2); aviation color code Orange. Source: US Geological Survey Cascades Volcano Observatory (CVO)
Tungurahua (Ecuador) | 10 May-16 May 2006 | Continuing ActivityCite this Report
Tungurahua Northern Andean Volcanic Arc	During 15-16 May, small-to-moderate explosions at Tungurahua produced plumes composed of gas, steam, and small amounts of ash. A news article reported that on 15 May blasts could be heard within 20 km of the volcano, and a moderate-to-large explosion was heard in nearby communities. On 16 May, a plume reached a height of ~2 km above the crater (or 23,000 ft a.s.l.) and drifted W. Sources: Washington Volcanic Ash Advisory Center (VAAC), Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN)
Ubinas (Peru) | 10 May-16 May 2006 | Continuing ActivityCite this Report
Ubinas Central Andean Volcanic Arc	Based on information from significant meteorological advisories (SIGMET) and pilot reports, the Buenos Aires VAAC reported that ash emitted from Ubinas during 9-11 and 13-14 May rose to a maximum height of 7.3 km (24,000 ft) a.s.l. Source: Buenos Aires Volcanic Ash Advisory Center (VAAC)
Ulawun (Papua New Guinea) | 10 May-16 May 2006 | Continuing ActivityCite this Report
Ulawun Bismarck Volcanic Arc	On 14 May, an ash plume from Ulawun of unknown height was visible on satellite imagery. Source: Darwin Volcanic Ash Advisory Centre (VAAC)

Weekly Reports Archive

Since the Weekly Volcanic Activity Report began in November 2000, there have been 20,627 individual reports over 1,243 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)