All times are local unless otherwise stated.

Fourpeaked (United States) | 27 September-3 October 2006 | New Activity / Unrest Cite this Report

Fourpeaked Alaska Peninsula Volcanic Arc

Volcanic unrest continued at Fourpeaked volcano during 23-29 September. Satellite observations by scientists from the University of Maryland-Baltimore County indicate that sulfur dioxide emission was continuing. Early in the week, AVO conducted several helicopter and fixed-wing missions during which observers photographed a linear series of vents running N from the summit for about 1 km. Some of the vents were vigorously emitting steam and other volcanic gases. Thermal measurements of up to 75°C were recorded at the vents, although steam was likely obscuring hotter areas. Adjacent glacial ice had been disrupted and showed signs of subsidence. Airborne gas measurements taken on 23, 24, and 30 September documented high emission rates of sulfur dioxide, hydrogren sulfide, and carbon dioxide, and a distinct sulfur smell was evident up to 50 km from the summit. An AVO status report on 3 October noted that cloudy conditions had prevented visual or satellite observations, but limited seismic data now being received did not indicate significant volcanic activity. Source: US Geological Survey Alaska Volcano Observatory (AVO)

Fuego (Guatemala) | 27 September-3 October 2006 | Continuing ActivityCite this Report
Fuego Central America Volcanic Arc	INSIVUMEH reports noted that frequent explosions at Fuego during 14-29 September sent incandescent lava 75-100 m above the crater rim and generated hot avalanches SW towards the Taniluyá River. Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Karymsky (Russia) | 27 September-3 October 2006 | Continuing ActivityCite this Report
Karymsky Eastern Kamchatka Volcanic Arc	Seismic data and satellite observations reported by KVERT indicated that moderate ash eruptions of Karymsky continued during 23-29 September. Weak local shallow earthquakes occurred at a rate of 100-250 per day. Ash explosions were thought to have risen to about 4.5 km (14,800 ft) a.s.l. on 22 September, and up to 2.5 km (8,200 ft) a.s.l. on the other days of that week. A thermal anomaly over the volcanic crater was noted on 23 and 26-27 September. The Level of Concern Color Code remained at Orange. Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Kilauea (United States) | 27 September-3 October 2006 | Continuing ActivityCite this Report
Kilauea Hawaiian-Emperor Hotspot Volcano Group	Fountaining on 28 September was reported about 15 m inland of the W edge of the East Lae`apuki bench. Lava jetted about 30 m in the air accompanied by loud rumbling and jetting sounds. Over the next couple of days, 3-4 lava streams were visible on the W side of East Lae`apuki entry, as were incidents of tephra jetting and lava fountaining 15-23 m (50-75 ft) high. Glow had been visible from the East Lae`apuki entry and the Campout flow breakout on the pali, but not from the Ka`ili`ili entry. The consistent lack of visible glow from the Ka`ili`ili entry is due to its inability to build a very large bench, so its continuing activity remains hidden at the base of the seacliff. Observers reported on 28 September that the floor of Drainhole vent had collapsed, and was replaced by an overturning lava pond. As of 29 September a new tube and flow were forming on the E side of the Campout flow. The USGS field crew also noticed a small stagnant breakout of lava at about 60 m (200 ft) elevation that flowed E to cover a little more of the long-abandoned Royal Gardens subdivision. Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
Mayon (Philippines) | 27 September-3 October 2006 | Continuing ActivityCite this Report
Mayon Eastern Philippine Volcanic Arc	In a 27 September report, PHIVOLCS noted continuing volcanic earthquakes, tremor episodes, and intermittent discharge of incandescent lava fragments along with intense glow from the crater. Steaming from the crater was moderate with white plumes drifting SW. Source: Philippine Institute of Volcanology and Seismology (PHIVOLCS)
Pacaya (Guatemala) | 27 September-3 October 2006 | Continuing ActivityCite this Report
Pacaya Central America Volcanic Arc	Lava flows have continued at Pacaya during 14-29 September, as reported by INSIVUMEH. The flows slowly advanced W towards Cerro Chino and NE towards Cerro Grande. White fumarolic emissions continued to rise from the MacKenney Cone. Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Santa Maria (Guatemala) | 27 September-3 October 2006 | Continuing ActivityCite this Report
Santa Maria Central America Volcanic Arc	Explosive activity at Santa María has continued to be reported during 21-29 September by INSIVUMEH. Two explosions on 21 September caused minor ashfall and small block avalanches. A pyroclastic flow the next day was generated by material coming off of Caliente dome. Additional explosions reported on 26 and 29 September again caused ashfall to the SW. Lava extrusion on the 29th triggered avalanches that sent blocks to the base of the crater. Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Soufriere Hills (United Kingdom) | 27 September-3 October 2006 | Continuing ActivityCite this Report
Soufriere Hills Lesser Antilles Volcanic Arc	Visual observations of Soufrière Hills during 22-29 September showed that the dome continued to grow at a moderate rate. Growth appeared to have occurred predominantly on the domes summit area, and on its eastern side, with a prominent lobe growing in this location. The vents just inside Gage's wall and on the summit of the dome periodically produced both ash and gases. There were also a number of pyroclastic flows during the period, some of which appear to have had explosive onsets in the seismic record. Northerly winds during 28 and 29 September resulted in minor ashfall in inhabited areas. The sulfur dioxide flux for the reporting period averaged around 450 tonnes/day, varying between 850 tonnes/day on 22 September and 190 tonnes/day on 26 September. Aviation ash advisories on 2-3 October described continuous ash emissions reaching 2.4 km (8,000 ft) a.s.l. that eventually extended 140 km W. Sources: Montserrat Volcano Observatory (MVO), Washington Volcanic Ash Advisory Center (VAAC)
St. Helens (United States) | 27 September-3 October 2006 | Continuing ActivityCite this Report
St. Helens High Cascades Volcanic Arc	There were minor rockfalls off of the new dome at St. Helens during 27 September-3 October as lava emerged slowly from the vent onto the S crater floor. Seismicity and rates of deformation were low. The new dome is now nearly as high as Shoestring notch on the SE crater wall. The alert-level system for all volcanoes monitored by the USGS was changed on 1 October from a numerical system to a descriptive system. In the new system, alert-level Normal indicates background conditions and is equivalent to aviation color-code Green. The previous alert levels of Volcanic Unrest (Alert Level 1), Volcano Advisory (Alert Level 2) and Volcano Alert (Alert Level 3) have changed to "Advisory," "Watch," and "Warning," respectively. There is a subtle change to the aviation color-code definitions in that there is no longer an ash-plume threshold given for either Orange or Red. For Mount St. Helens, the current hazard status is "Volcano alert level: Watch; Aviation color code ORANGE." The alert-level "Watch" is used for two different situations: (1) heightened or escalating unrest indicating a higher potential that an eruption is likely, but still not certain; or (2) an eruption that poses only limited hazard. Definition 2 fits the current lava-dome eruption at Mount St. Helens well. Source: US Geological Survey Cascades Volcano Observatory (CVO)
Tungurahua (Ecuador) | 27 September-3 October 2006 | Continuing ActivityCite this Report
Tungurahua Andean Northern Volcanic Arc	No ash emissions from Tungurahua were reported by the IG between 27 September and 2 October. However, a slow-moving lava flow was seen moving down the NNW flank on 2 October. Some fumarolic activity from the crater was observed this week when the weather was clear. On 3 October an explosion sent an ash plume to a height of 5 km above the summit, about 10 km (6,200 ft) a.s.l. Ash fell in nearby communities to the W. Multiple sources that contributed to an aviation ash advisory that indicated a higher-level plume to 9.8 km (32,000 ft) a.s.l. extending E to a distance of 22 km. Sources: Washington Volcanic Ash Advisory Center (VAAC), Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN)
Ubinas (Peru) | 27 September-3 October 2006 | Continuing ActivityCite this Report
Ubinas Andean Central Volcanic Arc	Aviation ash advisories for Ubinas, based on pilot reports, were issued by the Buenos Aires VAAC on 27, 28, and 30 September, and 1 October. The reports indicated continuous ash emissions. Source: Buenos Aires Volcanic Ash Advisory Center (VAAC)

Weekly Reports Archive

Since the Weekly Volcanic Activity Report began in November 2000, there have been 20,322 individual reports over 1,229 weeks (average of 17 per week) on 336 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.

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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)