All times are local unless otherwise stated.

Chikurachki | 30 April-6 May 2003 | Continuing ActivityCite this Report
Chikurachki Paramushir Island (Russia)	Chikurachki began erupting on 18 April 2003 and the eruption was clearly continuing through 25 April. Associated ash plumes were over 100 km long. During this week, 30 April-6 May, the Tokyo VAAC issued ash advisories on Chikurachki plumes for aviators. Early in the week the critical visual and satellite observations remained ambiguous with respect to the presence of ash in the atmosphere. On 2 May (at 1934 UTC) U.S. Airforce meteorologists detected Chikurachki ash emissions at ~3 km altitude and moving ESE at ~50 km/hour. Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Colima | 30 April-6 May 2003 | Continuing ActivityCite this Report
Colima Mexico	In the midst of an interval of ongoing tranquility, small explosive eruptions came from Colima on 2 May generating minor ash clouds visible on satellite imagery and local video monitoring. The ash clouds apparently rose no more than about 500 m above the crater. Source: Centro Universitario de Estudios Vulcanológicos (CUEV) - Universidad de Colima
Fuego | 30 April-6 May 2003 | Continuing ActivityCite this Report
Fuego South-Central Guatemala	At the end of April U.S. Air Force meteorologists used GOES-12 imagery to describe a thin plume of Fuego's ash that rose to ~7 km a.s.l. and blew SW at 20-30 km/hour. The ash plume was visible for over an hour. On 2 May the Washington VAAC reported that Fuego discharged small eruptions, with most ash remaining near the summit and little if any ash clearly visible on satellite imagery. Sources: Washington Volcanic Ash Advisory Center (VAAC), US Air Force Weather Agency
Guagua Pichincha | 30 April-6 May 2003 | Continuing ActivityCite this Report
Guagua Pichincha Ecuador	This week Guagua Pichincha was marked by low-to-modest seismicity, which included earthquakes on 30 April and 1 May with magnitudes less than 3. Both had epicenters within an earthquake swarm N of Quito. Episodes of harmonic tremor appeared, most noteworthy on 4 and 5 May with each episode lasting under 40 minutes. Cloud cover obscured the crater area for much of the week (during 30 April and on 2 and 4 May), and civil defense observers monitoring the volcano noted little in the way of sulfurous odors and no noise. Improved visibility on 3 May enabled these observers to see modest fumaroles, with condensate visible at 3 to 100 m heights. This week's observations were similar to those of January, February, and March 2003. Source: Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN)
Kilauea | 30 April-6 May 2003 | Continuing ActivityCite this Report
Kilauea Hawaiian Islands (USA)	Lava flows continued to descend the S flanks and pour into the sea. Distances measured across Kilauea caldera between two points ~10 km apart, remained stable as they have since early 2003. There had been consistent progressive lengthening of this distance during late 2001 through mid-2002, and some minor fluctuations after that. In general, tilt during late April through 2 May changed little at Uwekahuna station (W side of the caldera), and showed a progressive decline at Pu`u `O`o station (E of the caldera). In the first few days of May slight inflationary tilt appeared at both stations. Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
Klyuchevskoy | 30 April-6 May 2003 | Continuing ActivityCite this Report
Klyuchevskoy Central Kamchatka (Russia)	KVERT reported above-background seismicity at Kliuchevskoi during the week ending 1 May. Specifically, there were 25 earthquakes over M 1.25 at ~30 km depth, and 19 earthquakes over M 1.25 at shallower depths, including some within the edifice. In addition, during the same week instruments registered numerous weak, shallow earthquakes, and continuous spasmodic tremor. Residents in the city of Klyuchi saw various gas-and-steam plumes rising to these heights above the crater: on 25 April up to 300 m; and several other late April plumes up to ~ 2 km. The plume of 28 April extended over 5 km to the SE. Videos suggested that plumes escaping the crater in the early morning hours of 2 May could have contained ash. Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Nyamulagira | 30 April-6 May 2003 | Continuing ActivityCite this Report
Nyamulagira DR Congo	A report issued on 2 May noted an inferred renewal of activity on Nyamuragira. Residents living in the villages of Katale and Tongo, the settlements closest to the volcano, reported rumblings on 30 April, in addition to clear noises of individual explosions. At the same time on 30 April the closest seismic station (Katale) recorded 18 clear explosion signals, directly followed by an important tectonic earthquake located beneath the volcano. In the next hours seismometers registered 7 type-C events and another important tectonic earthquake. Source: Observatoire Volcanologique de Goma (OVG)
Nyiragongo | 30 April-6 May 2003 | Continuing ActivityCite this Report
Nyiragongo DR Congo	UN peace keepers in the Democratic Republic of Congo provided volcanologists an early May helicopter flight. This presented very clear views of Nyiragongo, including the scene inside the active crater. Viewers reported seeing a significant plume containing gas and ash rising high above the volcano. Such activity is typical at Nyiragongo, with its restless lava lake. The lake's molten surface appeared slightly larger than when seen during a field excursion to the crater rim during 22-24 April. The field excursion measured the plume at 5-6 km a.s.l. The also noted 5 distinct vents, almost continuous emissions of scoria, an agitated molten-lake surface that included emerging gas, and splashing lava thrown 50-60 m high. Occasional waves of lava rolled across portions of the crater floor and walls. Excursion members also witnessed crater-wall collapses taking place along the NW and S fracture zones. Widely felt earthquakes also continued in the region, presumably related to extension along the massive East African rift system. Sources: Observatoire Volcanologique de Goma (OVG), The Open University Volcano Dynamics Group
Tungurahua | 30 April-6 May 2003 | Continuing ActivityCite this Report
Tungurahua Ecuador	Although limited visibility often prevailed, Tungurahua's behavior alternated between days of tranquility and those with small to moderate explosions. Few earthquakes occurred. On 1 May an explosion sent ash to 2 km above the summit; incandescent material fell onto the flanks up to 800 m from the crater. Source: Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN)
Ulawun | 30 April-6 May 2003 | Continuing ActivityCite this Report
Ulawun New Britain (Papua New Guinea)	During this week, aviation sources reported Ulawun ash plumes. A 30 April volcanic ash advisory detected a possible narrow low-level plume extending ~50 km from Ulawun. Satellite imagery for 2 May indicated an ash-and-steam plume rising to ~4 km and blowing W at ~30 km/hour. The plume extended 80 km W of the summit. Sources: Darwin Volcanic Ash Advisory Centre (VAAC), US Air Force Weather Agency

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)