All times are local unless otherwise stated.

Bulusan (Philippines) | 23 May-29 May 2007 | New Activity / Unrest Cite this Report
Bulusan Eastern Philippine Volcanic Arc	According to news articles, scientists from PHIVOLCS conducted an aerial investigation of Bulusan and discovered lahar deposits and three steaming fissures. Lahars were previously reported from the municipalities of Irosin and Juban on 22 May. Scientists also observed steam plumes that rose to altitudes of 1.6-1.7 km (5,200-5,600 ft) a.s.l. and drifted NW and NE. PHIVOLCS reported that the S flank inflated 3 mm. Sources: GMA News, ABS-CBN News
Klyuchevskoy (Russia) | 23 May-29 May 2007 | New Activity / Unrest Cite this Report
Klyuchevskoy Eastern Kamchatka Volcanic Arc	KVERT reported that during 18-25 May, seismic activity at Kliuchevskoi continued above background levels and a thermal anomaly in the crater was detected on satellite imagery. On 18 May, ashfall was reported from the town of Klyuchi, about 30 km to the NE. According to video data and visual observations, Vulcanian activity at the summit crater and phreatic bursts on the NW flank of the volcano were observed during 22-24 May. Ash plumes rose to 5-8 km (16,000-25,600 ft) a.s.l. and drifted SE. Plumes were visible on satellite imagery drifting N, NE, and SE during the reporting period. Clouds inhibited observation on other days. The Level of Concern Color Code remained at Red. Based on satellite image observations and information from KVERT, the Tokyo VAAC reported that ash emissions produced possible plumes on 26 May to an altitude of 6.4 km (21,000 ft) a.s.l. and on 27 May to an altitude of 10.1 km (33,000 ft) a.s.l. Plumes drifted E, S, SW, and W. Ash plumes were also observed on satellite imagery during 28-29 May drifting S, SW, and W. Sources: Kamchatkan Volcanic Eruption Response Team (KVERT), Tokyo Volcanic Ash Advisory Center (VAAC)
Llaima (Chile) | 23 May-29 May 2007 | New Activity / Unrest Cite this Report
Llaima Southern Andean Volcanic Arc	Based on a Significant Meteorological Information (SIGMET) advisory and satellite image observations, the Buenos Aires VAAC reported that ash plumes from Llaima rose to altitudes of 3-4.3 km (10,000-14,000 ft) a.s.l. on 26 May. The plumes were visible on satellite imagery drifting E. On 28 May, a pilot reported that an ash plume rose to 5.5-6.7 km (18,000-22,000 ft) a.s.l. and drifted E. Source: Buenos Aires Volcanic Ash Advisory Center (VAAC)
Ritter Island (Papua New Guinea) | 23 May-29 May 2007 | New Activity / Unrest Cite this Report
Ritter Island Bismarck Volcanic Arc	On 30 May, RVO reported observations of Ritter Island following reports of a possible eruption and "sea surges" that destroyed homes on 19 May. On the S part of the island, scorched vegetation was observed and dead marine life (mainly reef fish) was seen around the coast line at heights of 4-6 m a.s.l. There was no evidence of fresh volcanic material, but a new landslide scar extended from the upper most part of the island down to sea level. Several more landslide scars were seen on the W wall. The estimated wave surge height resulting from the 19 May event reached 4-10 m, particularly around the S part of the island. Rockfalls continued to produce plumes that could be seen from a distance. Source: Rabaul Volcano Observatory (RVO)

Aira (Japan) | 23 May-29 May 2007 | Continuing ActivityCite this Report
Aira Ryukyu Volcanic Arc	Based on information from JMA and a pilot report, the Tokyo VAAC reported that ash plumes from Sakura-jima rose to altitudes of 1.8-2.1 km (6,000-7,000 ft) a.s.l. during 23-24 and 26-28 May. Plumes drifted E and SE and rose straight up. Source: Tokyo Volcanic Ash Advisory Center (VAAC)
Bagana (Papua New Guinea) | 23 May-29 May 2007 | Continuing ActivityCite this Report
Bagana Solomon Volcanic Arc	Based on satellite image observations and information from RVO, the Darwin VAAC reported that a diffuse ash-and-steam plume rose to an altitude of 3.7 km (12,000 ft) a.s.l. on 22 May and drifted W. Another diffuse plume was visible on satellite imagery to an altitude of 3 km (10,000 ft) a.s.l. on 28 May. Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Fuego (Guatemala) | 23 May-29 May 2007 | Continuing ActivityCite this Report
Fuego Central America Volcanic Arc	On 25 May, CONRED reported that the Alert Level for Fuego was lowered from Yellow to Green based on recent communication with nearby communities and monitoring by scientists at INSIVUMEH. During 28-29 May, INSIVUMEH reported that the lava flow on the S flank continued to advance and produce incandescent blocks that rolled W into the Taniluyá River valley. Low rumbling noises were heard during 26-27 May and occasionally accompanied pyroclastic explosions. Additional explosions produced plumes to an altitude of 4.1 km (13,500 ft) a.s.l. and expelled incandescent material about 100 m above the crater. Avalanches of blocks were observed on the S and SW flank. Gray plumes drifted S. Steam-and-gas plumes rose to an altitude of 4.6 km (15,100 ft) a.s.l. Sources: Coordinadora Nacional para la Reducción de Desastres (CONRED), Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Karymsky (Russia) | 23 May-29 May 2007 | Continuing ActivityCite this Report
Karymsky Eastern Kamchatka Volcanic Arc	Seismic activity at Karymsky was slightly above background levels during 18-25 May. A possible ash plume rose to an altitude of 2 km (6,400 ft) a.s.l. on 18 May. The Level of Concern Color Code remained at Orange. Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Kilauea (United States) | 23 May-29 May 2007 | Continuing ActivityCite this Report
Kilauea Hawaiian-Emperor Hotspot Volcano Group	During 23-29 May, lava from Kilauea flowed SE across a growing lava delta into the ocean at the Poupou entry. By 24 May, lava no longer entered the ocean at the Kamokuna entry. Incandescence was visible from several vents in the Pu'u 'O'o crater and from breakouts above and at the base of the Pulama pali fault scarp. The earthquake swarm that began on 12 May continued S and E of Halema'uma'u, in the upper E rift zone, and at scattered locations in the S flank. On 24 May, HVO recorded a M 4.7 earthquake at 0913, located beneath the upper E rift zone, near Puhimau crater, at a depth of 2 km. A M 4.1 aftershock occurred 20 minutes later and was located 1.5 km farther down-rift, beneath Koko'olau crater. A M 3.9 aftershock occurred at 1051 and was located another 2.5 km down-rift at a depth of 1 km. Since 1998, a few earthquakes with magnitudes greater than 4.0 have occurred at shallow depths beneath the upper E rift zone. Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
Lascar (Chile) | 23 May-29 May 2007 | Continuing ActivityCite this Report
Lascar Central Andean Volcanic Arc	Based on a Significant Meteorological Information (SIGMET) advisory and satellite image observations, the Buenos Aires VAAC reported that an ash plume from Lascar rose to an altitude of 9.1 km (30,000 ft) a.s.l. on 23 May and drifted SSE. Source: Buenos Aires Volcanic Ash Advisory Center (VAAC)
Manam (Papua New Guinea) | 23 May-29 May 2007 | Continuing ActivityCite this Report
Manam Bismarck Volcanic Arc	Based on satellite image observations and information from RVO, the Darwin VAAC reported that diffuse plumes from Manam rose to an altitude of 3 km (10,000 ft) a.s.l. on 23 May and drifted SW and W. Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Merapi (Indonesia) | 23 May-29 May 2007 | Continuing ActivityCite this Report
Merapi Sunda Volcanic Arc	According to a news article, "hot clouds" and incandescent material from Merapi traveled a distance of 1 km SE down the Gendol River on 23 May. People in the nearby village of Muntilan, about 16 km W, reported "hot clouds" and ashfall. Source: Antara News
Reventador (Ecuador) | 23 May-29 May 2007 | Continuing ActivityCite this Report
Reventador Northern Andean Volcanic Arc	Based on information from IG, the Washington VAAC reported that an ash plume from Reventador rose to an altitude of 3.7 km (12,000 ft) a.s.l. on 18 May and drifted NW. Ash was not observed on satellite imagery. Source: Washington Volcanic Ash Advisory Center (VAAC)
Sangay (Ecuador) | 23 May-29 May 2007 | Continuing ActivityCite this Report
Sangay Northern Andean Volcanic Arc	Based on pilot observations, the Washington VAAC reported that an ash plume from Sangay rose to an altitude of 7.3 km (24,000 ft) a.s.l. on 24 May. Source: Washington Volcanic Ash Advisory Center (VAAC)
Semeru (Indonesia) | 23 May-29 May 2007 | Continuing ActivityCite this Report
Semeru Sunda Volcanic Arc	Based on a pilot report and information from CVGHM, the Darwin VAAC reported diffuse ash plumes from Semeru at an altitude of 4.6 (15,000 ft) a.s.l. on 25 May. The plumes drifted W. Ash was not detected on satellite imagery. Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Sheveluch (Russia) | 23 May-29 May 2007 | Continuing ActivityCite this Report
Sheveluch Eastern Kamchatka Volcanic Arc	KVERT reported that seismic activity at Shiveluch continued above background levels during 18-25 May. Based on seismic interpretation, ash plumes possibly rose to altitudes of 4-8 km (13,100-26,200 ft) a.s.l. throughout the reporting period. Plumes were visible on satellite imagery drifting N, NE, and NW during 17-19 May. A large thermal anomaly was also visible on satellite imagery. The Level of Concern Color Code remained at Orange. Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Soufriere Hills (United Kingdom) | 23 May-29 May 2007 | Continuing ActivityCite this Report
Soufriere Hills Lesser Antilles Volcanic Arc	Based on visual observations, MVO reported that during 18-25 May lava-dome growth at Soufrière Hills likely ceased and the overall structure of the dome changed very little. Seismic activity was very low. The Alert Level remained at 4 (on a scale of 0-5). Source: Montserrat Volcano Observatory (MVO)
St. Helens (United States) | 23 May-29 May 2007 | Continuing ActivityCite this Report
St. Helens High Cascades Volcanic Arc	Data from deformation-monitoring instruments indicated that during 23-29 May lava-dome growth at Mount St. Helens continued. Seismicity persisted at low levels, punctuated by M 1.5-2.5, and occasionally larger, earthquakes. In some instances, clouds inhibited visual observations. Source: US Geological Survey Cascades Volcano Observatory (CVO)
Tungurahua (Ecuador) | 23 May-29 May 2007 | Continuing ActivityCite this Report
Tungurahua Northern Andean Volcanic Arc	IG reported that during 23-29 May, steam and steam-and-ash plumes intermittently visible from Tungurahua rose to altitudes of 6-8 km (19,700-26,200 ft) a.s.l. and drifted NW and W. Ashfall was reported from areas SW on 25 May, W and SW on 26 and 29 May, and NW on 27 May. Source: Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN)
Ubinas (Peru) | 23 May-29 May 2007 | Continuing ActivityCite this Report
Ubinas Central Andean Volcanic Arc	Based on pilot reports, observations from satellite imagery, and Significant Meteorological Information (SIGMET) advisories, the Buenos Aires VAAC reported that during 22-28 May ash plumes from Ubinas rose to altitudes of 5.5-7.3 km (18,000-24,000 ft) a.s.l. Plumes drifted NE, E, and ESE. Source: Buenos Aires Volcanic Ash Advisory Center (VAAC)

Weekly Reports Archive

Since the Weekly Volcanic Activity Report began in November 2000, there have been 20,627 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.

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)