All times are local unless otherwise stated.

Machin | 12 May-18 May 2004 | New Activity / Unrest Cite this Report
Machin Colombia	According to news articles, the Observatory Vulcanológico and Sismológico de Manizales reported that there was an increase in seismicity at Machín in April. About 60 earthquakes were recorded daily, in comparison to the 1-10 earthquakes normally recorded. No surficial changes were seen at the volcano. Sources: El Tiempo, El Tiempo
Mayon | 12 May-18 May 2004 | New Activity / Unrest Cite this Report
Mayon Luzon (Philippines)	According to a news article, PHIVOLCS reported that three volcanic earthquakes were recorded at Mayon during the week of 9 May, suggesting a renewed period of unrest. In addition, incandescence was visible in the crater and moderate steaming was seen. On 12 May, the sulfur-dioxide flux increased from the normal level of ~500 tons per day to ~1,170 tons. People were reminded not to enter the 6-km-diameter Permanent Danger Zone around Mayon. Source: ABS-CBN News
Sirung | 12 May-18 May 2004 | New Activity / Unrest Cite this Report
Sirung Pantar Island	According to a news article, Sirung began erupting "smoke and dust" around 13 May. A local government official reportedly said that hundreds of residents were evacuated from within 1 or 2 kilometers of the volcano. There were no reports of injuries or damage. Source: ABC News - Australian Broadcasting Corporation
Tenerife | 12 May-18 May 2004 | New Activity / Unrest Cite this Report
Tenerife Canary Islands	Local volcanologists reported that there was increased seismicity at Tenerife in mid-May, according to a news article. The article stated that during several days before 18 May there were "five successive low-intensity earthquakes in the island's most volcanically active zone in the area between Mont Teide and Santiago del Teide." The director of the Estación Vulcanológica de Canarias stated that the earthquakes, which were less than M 2, could be an early sign that something unusual was happening at the volcano. Source: Yorkshire Post Today News

Aira | 12 May-18 May 2004 | Continuing ActivityCite this Report
Aira Kyushu (Japan)	Based on information from JMA, the Tokyo VAAC reported that explosions at Sakura-jima occurred on 15 May at 1107 and on 17 May at 1946, sending ash plumes to heights of ~1.8 km and 2.1 km a.s.l., respectively. A pilot reported ash on 18 May, at a height of ~1.2 km a.s.l., ~23 km S of the Amori region. Sources: Tokyo Volcanic Ash Advisory Center (VAAC), Associated Press, Itar-Tass News
Anatahan | 12 May-18 May 2004 | Continuing ActivityCite this Report
Anatahan Mariana Islands (USA)	During 13-17 May, volcanic activity continued at Anatahan. Explosions occasionally threw volcanic material hundreds of meters out of the crater, and steam-and-ash emissions probably rose several hundred meters above the volcano. On 17 May the seismic energy release nearly doubled in comparison to the previous several days, but remained well below the peak level reached on 24 April. Source: Emergency Management Office of the Commonwealth of the Mariana Islands and United States Geological Survey Volcano Hazards Program
Colima | 12 May-18 May 2004 | Continuing ActivityCite this Report
Colima Mexico	Universidad de Colima reported on 15 May that low-intensity activity continued at Colima, with an average of three ash-containing explosions daily during the previous few days. The plumes rose to less than 2 km above the volcano and drifted W, N, and E. Some explosions produced pyroclastic flows to distances less than 2 km. On 14 May at 1028 an explosion produced a plume to ~2 km above the volcano that drifted E. In addition, three small pyroclastic flows traveled down the volcano's W, N, and E flanks. Sources: Washington Volcanic Ash Advisory Center (VAAC), Centro Universitario de Estudios Vulcanológicos (CUEV) - Universidad de Colima
Fuego | 12 May-18 May 2004 | Continuing ActivityCite this Report
Fuego South-Central Guatemala	During 10-17 May, moderate volcanic activity continued at Fuego. Several explosions produced ash plumes, with the highest one reaching ~1.8 km above the volcano on 13 May. Explosions on 13 May at 0411 and 0618 emitted incandescent volcanic material ~150 m. In addition, a lahar traveled W toward Seca Ravine. Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Karymsky | 12 May-18 May 2004 | Continuing ActivityCite this Report
Karymsky Eastern Kamchatka (Russia)	During 7-14 May, seismicity was above background levels at Karymsky, with 330-450 shallow earthquakes occurring daily. Based on interpretations of seismic data, possible ash-and-gas explosions rose to 2.5-3 km a.s.l. daily. On 8 May an ash plume was visible extending more than 16 km NE of the volcano. Karymsky remained at Concern Color Code Orange. Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Kilauea | 12 May-18 May 2004 | Continuing ActivityCite this Report
Kilauea Hawaiian Islands (USA)	On 12 May, the Banana lava flow at Kilauea stopped moving toward the sea. There were several incandescent areas along the route of the flow from Paliuli to the top of Pulama pali. During the report period, tremor was at low levels at Kilauea's summit and at moderate levels at Pu`u `O`o. A deflation-inflation-deflation event occurred at Kilauea's summit on 15 May. Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
Nyamulagira | 12 May-18 May 2004 | Continuing ActivityCite this Report
Nyamulagira DR Congo	During a flight over Nyamuragira on 12 May scientists noted that volcanic activity remained strong, but stable. The lava lake at the volcano's summit was in a ~15-m-deep pit and its activity had greatly decreased in comparison to observations on 9 May. The lake's surface had crusted over, with three vents exhibiting Strombolian activity (lava spattering and overflows producing short lava flows). In addition, the eruptive fracture on the volcano's NNW flank had four main cones with very active lava fountains reaching heights of 30-50 m. Small lava flows from the cones coalesced into one wide lava flow, covering a large area to a distance of ~12 km. The TOMS (Total Ozone Mapping Spectrometer) Volcanic Emissions Group reported that sulfur-dioxide clouds were visible on TOMS satellite imagery since the eruption began on 8 May, although some of the gas may be attributed to emissions from neighboring Nyiragongo (~13 km SE from Nyamuragira). Sources: Observatoire Volcanologique de Goma (OVG), OMI Sulfur Dioxide Group
Piton de la Fournaise | 12 May-18 May 2004 | Continuing ActivityCite this Report
Piton de la Fournaise Reunion Island (France)	The eruption that began at Piton de la Fournaise on 2 May continued through 15 May. After 2 days of low activity, eruption tremor increased by about a factor of 3 on the morning of 15 May. Lava flows followed the S border of Enclos Fouqué caldera and flowed down the Grandes Pentes area. Source: Observatoire Volcanologique du Piton de la Fournaise (OVPF)
Reventador | 12 May-18 May 2004 | Continuing ActivityCite this Report
Reventador Ecuador	During 3-9 May, the level of seismicity at Reventador did not change significantly. During 7-8 May, lahars traveled down Reventador's flanks, disrupting travel on the Chaco-Lumbaquí road for about a day. Source: Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN)
Santa Maria | 12 May-18 May 2004 | Continuing ActivityCite this Report
Santa Maria Southwestern Guatemala	During 10-17 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. Small partial collapses at the edge of the Caliente lava dome produced avalanches of incandescent volcanic material to the SW. On 17 May a lahar traveled S down Nimá River I. Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Sheveluch | 12 May-18 May 2004 | Continuing ActivityCite this Report
Sheveluch Central Kamchatka (Russia)	During 7-14 May seismic activity was above background levels at Shiveluch, with a large number of shallow earthquakes occurring. Based on interpretations of seismic data, during 6-7 May there may have been three ash-and-gas explosions that produced plumes to ~ 7 km a.s.l. On 9 May a strong explosion deposited ash in Ust-Kamchatsk, closing the airport. The road and the dam in the area of the Bekesh river were destroyed by mud flows. Sources: Kamchatkan Volcanic Eruption Response Team (KVERT), Tokyo Volcanic Ash Advisory Center (VAAC)
Shishaldin | 12 May-18 May 2004 | Continuing ActivityCite this Report
Shishaldin Fox Islands (USA)	During 7-14 May seismic unrest continued at Shishaldin, characterized by sequences of volcanic earthquakes, small explosions, and seismic tremor. A weak thermal anomaly observed at Shishaldin's summit on 11 May was similar to those detected occasionally since January 2004. Shishaldin remained at Concern Color Code Yellow. Source: US Geological Survey Alaska Volcano Observatory (AVO)
Soufriere Hills | 12 May-18 May 2004 | Continuing ActivityCite this Report
Soufriere Hills Montserrat	Volcanic and seismic activity at Soufrière Hills remained at low levels during 7-14 May. Spasmodic tremor ceased on 7 May, ending a protracted period of low-to-moderate amplitude tremor that began on 15 March. The sulfur-dioxide flux was at low-to-moderate levels, reaching the lowest recorded value on 13 May (146 metric tons per day) since the major explosions and collapse event during 12-15 July 2003. Source: Montserrat Volcano Observatory (MVO)
Tungurahua | 12 May-18 May 2004 | Continuing ActivityCite this Report
Tungurahua Ecuador	During 12-17 May, moderate emissions of steam, gas, and ash continued at Tungurahua. On 12 May, an explosion produced an ash cloud to ~3 km above the volcano that drifted SW. On 13 May seismicity increased moderately, related to the increased numbers of emissions. Incandescence was visible at the lava dome during some nights. Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN), Washington Volcanic Ash Advisory Center (VAAC)
Veniaminof | 12 May-18 May 2004 | Continuing ActivityCite this Report
Veniaminof Alaska Peninsula, Alaska	During 7-14 May unrest continued at Veniaminof, characterized by intermittent low-level volcanic tremor and small volcanic earthquakes. No emissions were seen. In comparison to the previous week, seismicity was more intermittent and lower in amplitude. However, seismicity suggested that ash bursts occasionally occurred. 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 19,996 individual reports over 1,215 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.

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)