All times are local unless otherwise stated.

Awu (Indonesia) | 19 May-25 May 2004 | New Activity / Unrest Cite this Report
Awu Sangihe Volcanic Arc	DVGHM reported a sudden increase in seismicity at Awu beginning on 16 May when 12 volcanic earthquakes were recorded. In addition, tremor was recorded during 1110-1540. Gas plumes rose ~75 m above the crater that were thicker than earlier in the month, but they did not change color or form clumps. On 18 May, six volcanic earthquakes were recorded and tremor continued. The same day DVGHM raised the Alert Level from 1 to 2. According to news reports, on 21 May hundreds of residents of the villages of Manente, Kolongan, Kendahe, and North Tabukan began to flee due to fears of an eruption. Sources: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM), Agence France-Presse (AFP), The Jakarta Post
Sirung (Indonesia) | 19 May-25 May 2004 | New Activity / Unrest Cite this Report
Sirung Sunda Volcanic Arc	According to DVGHM, the news reports of an eruption at Sirung around 13 May were false. There was no activity at the volcano. Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)

Aira (Japan) | 19 May-25 May 2004 | Continuing ActivityCite this Report
Aira Ryukyu Volcanic Arc	Based on information from JMA, during 19-24 May several explosions at Sakura-jima produced ash clouds. The highest reported ash cloud reached ~2.4 km a.s.l. on 24 May. Source: Tokyo Volcanic Ash Advisory Center (VAAC)
Anatahan (United States) | 19 May-25 May 2004 | Continuing ActivityCite this Report
Anatahan Mariana Volcanic Arc	During 20-25 May, volcanic activity continued at Anatahan. Explosions every few minutes threw volcanic material hundreds of meters out of the crater, and steam-and-ash emissions probably rose several hundred meters above the volcano. On 25 May satellite imagery showed an ash plume extending at least 5 km NW of the volcano. Source: Emergency Management Office of the Commonwealth of the Mariana Islands and United States Geological Survey Volcano Hazards Program
Dukono (Indonesia) | 19 May-25 May 2004 | Continuing ActivityCite this Report
Dukono Halmahera Volcanic Arc	During 19-25 May, Dukono occasionally emitted ash plumes that were visible on satellite imagery. Plumes rose to heights of ~3 km a.s.l. Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Fuego (Guatemala) | 19 May-25 May 2004 | Continuing ActivityCite this Report
Fuego Central America Volcanic Arc	During 18-21 May, moderate volcanic activity continued at Fuego. Several explosions produced ash plumes, with the highest one reaching ~1.2 km above the volcano on 20 May. On 21 May, avalanches of incandescent volcanic material traveled toward the ravines of Seca (to the W) and Taniluya (to the SW). Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Kilauea (United States) | 19 May-25 May 2004 | Continuing ActivityCite this Report
Kilauea Hawaiian-Emperor Hotspot Volcano Group	During 19-21 May, the Banana lava flow traveled toward down the Pulama pali toward the sea, reaching within ~200 m of the sea cliff before stopping on the morning of 21 May. Around this time, a few incandescent areas were visible along the flow. During 19-23 May, tremor was at low levels at Kilauea's summit and at moderate levels at Pu`u `O`o. There were small episodes of inflation and deflation at the volcano. Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
Nyamulagira (DR Congo) | 19 May-25 May 2004 | Continuing ActivityCite this Report
Nyamulagira Albertine Rift Volcanic Province	The Toulouse VAAC reported that satellite imagery showed a weak eruption of ash at Nyamuragira on 25 May. Source: Toulouse Volcanic Ash Advisory Centre (VAAC)
Nyiragongo (DR Congo) | 19 May-25 May 2004 | Continuing ActivityCite this Report
Nyiragongo Albertine Rift Volcanic Province	The Toulouse VAAC reported that satellite imagery showed a weak eruption of Nyiragongo on 21 May. Activity intensified during the evening of 24 May. By the evening of 25 May, the volcano was no longer visible on satellite imagery due to meteorological clouds in the area. Source: Toulouse Volcanic Ash Advisory Centre (VAAC)
Piton de la Fournaise (France) | 19 May-25 May 2004 | Continuing ActivityCite this Report
Piton de la Fournaise Reunion Hotspot Volcano Group	The eruptive episode that began at Piton de la Fournaise on 2 May stopped on 18 May. This followed 2 days of high eruptive activity when numerous pahoehoe lava flows and Pele's hair were produced. Around 1550 on the 18th the amount of eruption tremor decreased, completely stopping at 1615 and signaling the eruption's end. Source: Observatoire Volcanologique du Piton de la Fournaise (OVPF)
Reventador (Ecuador) | 19 May-25 May 2004 | Continuing ActivityCite this Report
Reventador Northern Andean Volcanic Arc	Strong rain on 15 May caused several lahars to travel down Reventador's flanks. They persisted through 16 May. Source: Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN)
Santa Maria (Guatemala) | 19 May-25 May 2004 | Continuing ActivityCite this Report
Santa Maria Central America Volcanic Arc	During 18-21 May, weak-to-moderate explosions at Santa María's Santiaguito lava-dome complex produced gas-and-ash plumes that rose to ~1 km above the crater. Many of the moderate explosions were accompanied by avalanches of incandescent volcanic material. On 20 May around 1800 a small partial collapse at the edge of the Caliente lava dome produced an avalanche of incandescent volcanic material to the SW that reached the base of the dome. Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Semeru (Indonesia) | 19 May-25 May 2004 | Continuing ActivityCite this Report
Semeru Sunda Volcanic Arc	The Darwin VAAC reported that a thin ash plume from Semeru was visible on satellite imagery on 23 May around 0625. The plume reached a height of ~4.3 km a.s.l. and extended ~110 km SSE. Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Shishaldin (United States) | 19 May-25 May 2004 | Continuing ActivityCite this Report
Shishaldin Aleutian Ridge Volcanic Arc	During 14-21 May seismic unrest continued at Shishaldin, characterized by weak seismic tremor and small explosions. On 16 May, a pilot reported an ash plume that rose ~300 m above the volcano's summit. Satellite imagery from 17 May showed a vigorous plume emanating from the summit that may have contained small amounts of ash. Shishaldin remained at Concern Color Code Yellow. Source: US Geological Survey Alaska Volcano Observatory (AVO)
Soufriere Hills (United Kingdom) | 19 May-25 May 2004 | Continuing ActivityCite this Report
Soufriere Hills Lesser Antilles Volcanic Arc	Volcanic and seismic activity at Soufrière Hills during 14-21 May remained at low levels. On 21 May intense rainfall produced large mudflows in the Belham Valley. At the peak of the activity, the entire width of the valley floor at Belham Bridge was flooded and standing waves up to 2 m high were observed. The sulfur-dioxide flux was low for most of the report period. Source: Montserrat Volcano Observatory (MVO)
Tungurahua (Ecuador) | 19 May-25 May 2004 | Continuing ActivityCite this Report
Tungurahua Northern Andean Volcanic Arc	During 19-24 May, small-to-moderate emissions of gas, steam, and ash continued at Tungurahua. The highest rising plume reached ~2.5 km above the volcano on 23 May. On the morning of 19 May a mudflow occurred in the Pampas sector, but it did not affect the highway. Strombolian activity was visible in the crater on the evening of 23 May. Sources: Washington Volcanic Ash Advisory Center (VAAC), Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN)
Veniaminof (United States) | 19 May-25 May 2004 | Continuing ActivityCite this Report
Veniaminof Aleutian Ridge Volcanic Arc	Unrest continued at Veniaminof during 14-21 May, characterized by intermittent volcanic tremor. The tremor was similar to seismic signals recorded the previous month in association with small ash plumes, suggesting that ash bursts continued. A pilot report on 18 May indicated the presence of an ash plume rising to heights of 300-900 m above the volcano's summit and extending ~32 km NE. Veniaminof remained at Concern Color Code Yellow. Source: US Geological Survey Alaska Volcano Observatory (AVO)

Weekly Reports Archive

Since the Weekly Volcanic Activity Report began in November 2000, there have been 21,515 individual reports over 1,280 weeks (average of 17 per week) on 341 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)