All times are local unless otherwise stated.

Mayon | 15 February-21 February 2006 | New Activity / UnrestCite this Report
Mayon Luzon (Philippines)	A minor explosion at Mayon on 21 February at 0941 produced an ash plume that rose to ~500 m above the volcano's crater (or 9,700 ft a.s.l.) and drifted SW. Ash was deposited on the upper slopes of the volcano. The ash emission was accompanied by a small explosion-type earthquake, recorded only by seismographs around the volcano. Prior to the explosion, an increase in seismicity was recorded at the volcano. Between 1545 on 20 February and 0520 on 21 February, there were 147 low-frequency volcanic earthquakes recorded, considerably above the five or fewer events per day that are normally recorded. Some minor rockfalls were indicated and probably resulted from detachment of lava blocks from the summit. Steaming was observed. No incandescence was visible at the crater due to clouds obscuring the volcano. Mayon remained at Alert Level 2, with a 6-km-radius Permanent Danger Zone in effect. PHIVOLCS expects similar ash explosions in the coming days as magma intrudes the summit area and releases volcanic gases. Source: Philippine Institute of Volcanology and Seismology (PHIVOLCS)
Miyakejima | 15 February-21 February 2006 | New Activity / UnrestCite this Report
Miyakejima Izu Islands	According to a news report, a minor eruption at Miyake-jima on 17 February consisted of small ash emissions. Residents of the island were warned that there could be gas emissions and mudslides. The Geological Survey of Japan, AIST website reported that the sulfur-dioxide flux at Miyake-jima averaged about 2,000-5,000 tons per day in January. Sources: Geological Survey of Japan, Associated Press

Ambae | 15 February-21 February 2006 | Continuing ActivityCite this Report
Ambae Vanuatu	A news article reported on 16 February that the 5,000 people who evacuated their homes after increased activity began at Aoba on 27 November 2005 returned home after Department of Geology and Mines officials reduced the threat level from 2 to 1. Source: Radio New Zealand
Augustine | 15 February-21 February 2006 | Continuing ActivityCite this Report
Augustine Alaska Peninsula	During 15-19 February, AVO seismometers at Augustine recorded occasional rockfalls and small pyroclastic-flow signals indicative of minor collapses of the volcano's lava dome. During the previous week, the number of these events declined, suggesting that the rate of lava effusion may have slowed. Clear satellite views of the volcano on 16 February showed a thermal anomaly in the summit crater area. On the 19th, the web camera showed a light dusting of ash on the ENE flank of the volcano. AVO stated that during the report period a plume composed of variable amounts of gas, steam, and small amounts of ash was probably being emitted intermittently from Augustine's summit. They warned that occasional very localized ash clouds and light ashfall will be produced by collapses from the lava dome. Augustine remained at Concern Color Code Orange. Sources: US Geological Survey Alaska Volcano Observatory (AVO), Anchorage Volcanic Ash Advisory Center (VAAC)
Galeras | 15 February-21 February 2006 | Continuing ActivityCite this Report
Galeras Colombia	During 13-20 February, seismicity continued at Galeras, with an average of about 190 small earthquakes occurring per day. A flux of about 200 metric tons of sulfur dioxide was measured daily. Steam and gas rose to ~1.1 km above the volcano (or ~17,600 ft a.s.l.) on 19 February. Incandescence was visible at parts of the lava dome. The volume of the lava dome in the main crater was approximately 1.5 times larger than when it was first observed on 13 January. Galeras remained at Alert Level 3 ("changes in the behavior of volcanic activity have been noted"). Note: It was incorrectly reported in the 8-14 February Weekly Volcanic Activity Report that on 8 February pyroclastic-flow deposits were found at Galeras. Pyroclastic-fall deposits were observed. Source: Servicio Geológico Colombiano (SGC)
Guagua Pichincha | 15 February-21 February 2006 | Continuing ActivityCite this Report
Guagua Pichincha Ecuador	IG reported that seismic activity at Guagua Pichincha during 6-12 February decreased in comparison to the previous week, confirming that a small increase in activity around 5 February was related to brief phreatic activity. No explosions occurred during the report period and low-level volcanic tremor was recorded. Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)
Karymsky | 15 February-21 February 2006 | Continuing ActivityCite this Report
Karymsky Eastern Kamchatka (Russia)	During 10-17 February, a large thermal anomaly was visible at Karymsky's crater and numerous ash plumes were visible on satellite imagery. Karymsky remained at Concern Color Code Orange. Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Kilauea | 15 February-21 February 2006 | Continuing ActivityCite this Report
Kilauea Hawaiian Islands (USA)	During 16-20 February, no surface lava flows were visible on Kilauea's Pulama pali fault scarp, which had been the case since 8 February. Several streams of lava poured into the sea from the lava delta at the East Lae`apuki entry. Background volcanic tremor was at normal levels at Kilauea's summit, with shallow earthquakes continuing to occur beneath the summit area and the upper east rift zone. Volcanic tremor reached moderate levels at Pu`u `O`o. Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
Rabaul | 15 February-21 February 2006 | Continuing ActivityCite this Report
Rabaul New Britain (Papua New Guinea)	RVO reported that during 30 January to 15 February, Rabaul caldera's Tavurvur cone continued to be relatively quiet. Variable amounts of gas were emitted from an active fumarole at the summit area on the upper part of the W flank. An average sulfur-dioxide flux of 200 metric tons per day was recorded and seismicity was at low levels. According to the Darwin VAAC, ash from Rabaul was visible on satellite imagery at a height of ~3.7 km (12,100 ft) a.s.l. on 17 February. Sources: Rabaul Volcano Observatory (RVO), Darwin Volcanic Ash Advisory Centre (VAAC)
Santa Maria | 15 February-21 February 2006 | Continuing ActivityCite this Report
Santa Maria Southwestern Guatemala	Several explosions occurred at Santa Maria's Santiaguito lava-dome complex during 15-17 February, with ash plumes rising to ~1.5 km above the volcano (or 17,300 ft a.s.l.). Some explosions were accompanied by small pyroclastic flows that traveled SW and NE down Caliente dome. Avalanches of incandescent volcanic material spalled off of active lava-flow fronts. Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Soufriere Hills | 15 February-21 February 2006 | Continuing ActivityCite this Report
Soufriere Hills Montserrat	MVO reported that during vigorous ash-and-steam venting at Soufrière Hills on 10 February, a small dark lobe of lava was observed on the western side of the lava dome in the crater. By early on 11 February this lobe had advanced rapidly towards the NE side of the dome and was visible as a steep-sided plateau of lava from inhabited areas around Salem. Photographs from fixed cameras showed continued changes to this lava lobe over the next few days, and the NE margin could be seen glowing at night and shedding rockfalls into the NE part of the crater. The initial growth rate of this lobe was well over 5 cubic meters per second, but the rate declined around 17 February. The new lava lobe began to fill the gap between the lava dome and the northern and western crater walls, raising the possibility that small rockfalls could spill over those areas in coming weeks. The sulfur-dioxide flux averaged 568 metric tons per day. Data from Fourier Transform Infra Red spectrometry measurements indicated an increase in the hydrogen chloride/sulfur dioxide mass ratio in the gas plume from 2.0 in the last reporting period to an average of 2.5 on 13 February. Sources: Washington Volcanic Ash Advisory Center (VAAC), Montserrat Volcano Observatory (MVO)
St. Helens | 15 February-21 February 2006 | Continuing ActivityCite this Report
St. Helens Washington	Growth of the new lava dome inside the crater of Mount St. Helens continued during 16-20 February, accompanied by low rates of seismicity, low emissions of steam and volcanic gases, and minor production of ash. Gas measurements made on 15 February suggested that the volcanic-gas flux remained unchanged from recent measurements. Observations made on 17 February revealed that the northeastern active part of the new lava dome was developing a steeply inclined jagged spine. At its top, temperatures as high as 580 degrees Celsius were measured using a thermal sensor. St Helens remained at Volcano Advisory (Alert Level 2); aviation color code Orange. Source: US Geological Survey Cascades Volcano Observatory (CVO)
Tungurahua | 15 February-21 February 2006 | Continuing ActivityCite this Report
Tungurahua Ecuador	Activity began to increase slightly at Tungurahua around 15 February. Several moderate explosions occurred during 15-19 February, with ash plumes rising as high as 3 km above the volcano (or 26,300 ft a.s.l.) on 15 February. Small amounts of ashfall were reported NW of the volcano in Cotaló, Cusúa, Pondoa, Bilbao, and at the Tungurahua Observatory (OVT) on the 18th. Rainfall generated a small mudflow SW of the volcano in the Quebrada Rea sector of Puela on 19 February. Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)

Weekly Reports Archive

Since the Weekly Volcanic Activity Report began in November 2000, there have been 18,995 individual reports over 1,169 weeks (average of 16 per week) on 329 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)