All times are local unless otherwise stated.

Anatahan (United States) | 30 July-5 August 2008 | New Activity / Unrest Cite this Report
Anatahan Mariana Volcanic Arc	During 30 July-5 August seismic tremor from Anatahan fluctuated. Gas-and-steam plumes possibly containing some ash were occasionally visible on satellite imagery at an altitude of 1.5 km (5,000 ft) a.s.l. and below. Plumes drifted W and NW. The Volcanic Alert Level remained at Watch and the Aviation Color Code remained at Orange. Source: Emergency Management Office of the Commonwealth of the Mariana Islands and United States Geological Survey Volcano Hazards Program
Chikurachki (Russia) | 30 July-5 August 2008 | New Activity / Unrest Cite this Report
Chikurachki Kuril Volcanic Arc	Based on observations of satellite imagery, KVERT reported that during 30-31July ash plumes from Chikurachki drifted S. The level of seismicity was unknown because Chikurachki lacks dedicated seismic instruments. The Level of Concern Color Code was raised to Orange. Based on reports from KVERT, the Tokyo VAAC reported that on 1 August, an ash plume rose to an altitude of 2.7 km (9,000 ft) a.s.l. and drifted SE. Sources: Kamchatkan Volcanic Eruption Response Team (KVERT), Tokyo Volcanic Ash Advisory Center (VAAC)
Cleveland (United States) | 30 July-5 August 2008 | New Activity / Unrest Cite this Report
Cleveland Aleutian Ridge Volcanic Arc	AVO reported that thermal anomalies at Cleveland's summit, detected on satellite imagery during 30 July-5 August, suggested the presence of an active lava flow. A diffuse plume drifted less than 20 km NE, N, and NW at an altitude of 6.1 km (20,000 ft) a.s.l. on 31 July. On 5 August, thermal anomalies on the W, S, and SE flanks possibly indicated the presence of pyroclastic flows or hot lahars. The Volcanic Alert Level remained at Watch and the Aviation Color Code remained at Orange. Source: US Geological Survey Alaska Volcano Observatory (AVO)
Llaima (Chile) | 30 July-5 August 2008 | New Activity / Unrest Cite this Report
Llaima Southern Andean Volcanic Arc	SERNAGEOMIN reported that scientists observed fumarolic activity from the edges of the nested cones in Llaima's main crater during aerial observations on 29 July. Sulfur dioxide plumes rose from an area in the E crater. Tephra deposits covered parts of the SE flank. Cooled lava flows emitted on 26 and 27 July were noted on the W flank. On 31 July, fumarolic activity from the crater was reported in multiple areas around the volcano. Cloudy conditions prevented visual observations during 1-2 August. The Alert level was Yellow on 2 August. Source: Servicio Nacional de Geología y Minería (SERNAGEOMIN)
Manam (Papua New Guinea) | 30 July-5 August 2008 | New Activity / Unrest Cite this Report
Manam Bismarck Volcanic Arc	Based on observations of satellite imagery and information from RVO, the Darwin VAAC reported that on 30 July a low-level plume from Manam rose to an altitude 2.4 km (8,000 ft) a.s.l. and drifted NW. Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Okmok (United States) | 30 July-5 August 2008 | New Activity / Unrest Cite this Report
Okmok Aleutian Ridge Volcanic Arc	Based on observations of satellite imagery and pilot reports, AVO reported that ash plumes from Okmok rose to altitudes of 4.6-10.7 km (15,000-35,000 ft) a.s.l. and drifted SW, W, N, NNE, and SE. On 30 July, seismicity alternated between continuous and pulsating volcanic tremor. The Volcano Alert Level was lowered to Watch and the Aviation Color Code was lowered to Orange. On 31 July, reports from a fishing boat 11.3 km N indicated no visibility due to ashfall. Strong volcanic tremor on 2 August prompted AVO to raise the Volcano Alert Level to Warning and the Aviation Color Code to Red. Cloudy conditions prevented satellite observations. Later that day, AVO geologists in the area reported that ash-and-steam plumes rose to minimum altitude of 6.1 km (20,000 ft) a.s.l. The seismicity decreased and the Volcano Alert Level was lowered to Watch and the Aviation Color Code was lowered to Orange. Observers in Ft. Glenn on Umnak Island reported smelling sulfur and seeing a larger ash plume than earlier that day. The plume drifted ESE. On 3 August, helicopter and ground-based observers indicated a lower-altitude ash plume along with a higher steam plume. Satellite imagery revealed that ash plumes at altitudes of 9.1-10.7 km (30,000-35,000 ft) a.s.l. drifted SSW. On 4 August, ashfall reported in Nikolski had accumulated to a depth of 3 mm. During 4-5 August satellite imagery and pilot observations indicated that ash plumes rose to altitudes of 3-7.6 km (10,000-25,000 ft) a.s.l. and drifted SW and W. Source: US Geological Survey Alaska Volcano Observatory (AVO)
Reventador (Ecuador) | 30 July-5 August 2008 | New Activity / Unrest Cite this Report
Reventador Northern Andean Volcanic Arc	The IG reported that seismicity from Reventador decreased during 30-31 July. On 31 July, steam-and-gas plumes with a low ash content were detected on satellite imagery and drifted W and SW. On 1 August, steam-and-gas plumes were emitted and a lava flow in the caldera was active. Diffuse ash emissions were noted on 2 August. On 3 August, IG scientists observed the lava flow in the caldera and estimated that it advanced at a rate of 100 m per day. They also heard sporadic roaring noises. Gas-and-steam plumes were noted on 5 August. Source: Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN)
Sumbing (Indonesia) | 30 July-5 August 2008 | New Activity / Unrest Cite this Report
Sumbing Sunda Volcanic Arc	Based on pilot observations, the Darwin VAAC reported that an eruption plume from Sumbing rose to an altitude of 4.9 km (16,000 ft) a.s.l. and drifted W. Ash was not identified on satellite imagery. [Correction: CVGHM later confirmed that Sumbing did not erupt on 1 August and attributed the plume origin to either a different volcano or a bushfire that was reported in the area.] Source: Darwin Volcanic Ash Advisory Centre (VAAC)

Batu Tara (Indonesia) | 30 July-5 August 2008 | Continuing ActivityCite this Report
Batu Tara Sunda Volcanic Arc	Based on observations of satellite imagery, the Darwin VAAC reported that during 30-31 July diffuse plumes from Batu Tara rose to an altitude of 1.5 km (5,000 ft) a.s.l. and drifted W. Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Chaiten (Chile) | 30 July-5 August 2008 | Continuing ActivityCite this Report
Chaiten Southern Andean Volcanic Arc	SERNAGEOMIN reported that clouds obscured camera views of Chaitén's eruption plume during most of 30-31July. A glimpse on 31 July revealed that a steam-and-ash plume rose to an altitude of 1.5 km (4,900 ft) a.s.l. Explosions were heard. A steam-and-ash plume was seen at an altitude of about 3.1 km during an overflight on 31 July and drifted NE. The plume was emitted from a fracture caused by a vertical collapse of the S flank of the lava dome. A horseshoe-shaped scar on the E side of the dome, about 500 m wide and 200 m high, formed on an unknown date within the previous several days. The scar was inferred to have formed by a lateral explosion rather than collapse because hummocky morphology typical of landslide deposits was not found below the scar. Material from the explosion was transported by rivers that eventually flowed N into the Rayas River, and also fell in small lagoons at the S base of the dome. On 4 August a small steam plume possibly containing some ash was seen through another quick break in the clouds and drifted E. Source: Servicio Nacional de Geología y Minería (SERNAGEOMIN)
Fuego (Guatemala) | 30 July-5 August 2008 | Continuing ActivityCite this Report
Fuego Central America Volcanic Arc	INSIVUMEH reported that a lahar descended El Jute River to the SE of Fuego on 31 July, carrying fine material as well as blocks. A report on 1 August indicated that explosions produced ash plumes that rose to an altitude of 4.1 km (13,500 ft) a.s.l. and drifted W and SW. Rumbling noises and shockwaves occasionally accompanied the explosions. Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Karymsky (Russia) | 30 July-5 August 2008 | Continuing ActivityCite this Report
Karymsky Eastern Kamchatka Volcanic Arc	KVERT reported that seismic activity at Karymsky was above background levels during 25 July-1 August and possibly indicated that explosions produced ash plumes to an altitude of 3.7 km (12,100 ft) a.s.l. According to area volcanologists and pilots, ash plumes rose to altitudes of 5-6 km (16,400-19,700 ft) a.s.l. on 25 July. Observations of satellite imagery revealed a daily thermal anomaly in the crater. The Level of Concern Color Code remained at Orange. Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Kilauea (United States) | 30 July-5 August 2008 | Continuing ActivityCite this Report
Kilauea Hawaiian-Emperor Hotspot Volcano Group	HVO reported that during 30 July-5 August lava flowed SE through a lava tube system from underneath Kilauea's Thanksgiving Eve Breakout (TEB) and rootless shield complex to the Waikupanaha ocean entry. Explosions from the ocean entry were noted on 30 July. On 31 July, about 2.3 acres (or 25 percent) of the bench E of the ocean entry collapsed. A small lava pond at the top of one of the rootless shields was observed during an overflight. The sulfur dioxide emission rate at Pu'u 'O'o was 1,800 tonnes per day on 31 July; the average background rate is about 2,000 tonnes per day. During the reporting period, Kilauea earthquakes were variously located beneath Halema'uma'u crater, along the Koa'e fault system, N of the summit, along the S-flank faults, and along the E and SW rift zones. Beneath Halema'uma'u crater, 40 or fewer small earthquakes per day also occurred but were too small to be located more precisely. The vent in Halema'uma'u crater continued to produce a mainly white plume with minor ash content that drifted SW, then occasionally rotated SE. During 1-3 August, seismic signals resembling those from explosions were accompanied an increase in plume vigor and by the color turning temporarily brown. An event on 1 August started with a collapse of a small portion of the vent rim and was followed by ejected incandescent tephra. Night-time incandescence was seen at the base of the plume. Rushing and rock-clattering sounds were heard in the vicinity of the crater. The sulfur dioxide emission rate was high at 800 and 700 tonnes per day, on 31 July and 4 August, respectively. The pre-2008 background rate was 150-200 tonnes per day. Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
Rabaul (Papua New Guinea) | 30 July-5 August 2008 | Continuing ActivityCite this Report
Rabaul Bismarck Volcanic Arc	RVO reported that during 25 July-4 August, ash plumes from Rabaul caldera's Tavurvur cone rose to altitudes of 1.7-3.7 km (5,600-12,000 ft) a.s.l. and drifted W and NW. Ashfall was reported downwind in Rabaul town, Namanula Hill, Malaguna, and surrounding areas. Occasionally incandescence at the summit was observed and roaring noises were reported. During 31 July-4 August, incandescent lava fragments were ejected along with some of the more forceful ash emissions. Based on observations of satellite imagery and reports from RVO, the Darwin VAAC reported that low-level plumes rose to altitudes of 1.8-2.4 km (6,000-8,000 ft) a.s.l. and drifted NW during 5-6 August. Sources: Rabaul Volcano Observatory (RVO), Darwin Volcanic Ash Advisory Centre (VAAC)
Semeru (Indonesia) | 30 July-5 August 2008 | Continuing ActivityCite this Report
Semeru Sunda Volcanic Arc	CVGHM reported on 5 August that ash plumes from Semeru rose to altitudes of 4-4.3 km (13,100-14,100 ft) a.s.l. and were occasionally accompanied by ejected incandescent tephra. Based on visual observations and instrumental data, the Alert level remained at 2 (on a scale of 1-4). Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
Sheveluch (Russia) | 30 July-5 August 2008 | Continuing ActivityCite this Report
Sheveluch Eastern Kamchatka Volcanic Arc	KVERT reported that seismic activity at Shiveluch was slightly above background levels during 25 July-1 August. According to visual observations, small hot avalanches occasionally descended the lava dome and fumaroles were active on 18 and 22 July. Observations of satellite imagery revealed a thermal anomaly on the lava dome daily during the reporting period. The Level of Concern Color Code remained at Orange. Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Tungurahua (Ecuador) | 30 July-5 August 2008 | Continuing ActivityCite this Report
Tungurahua Northern Andean Volcanic Arc	The IG reported that during 30-31 July and 2-5 August, explosions from Tungurahua were detected by the seismic network. Although clouds occasionally prevented visual observations, ash plumes were observed that rose to altitudes of 6-9 km (19,700-29,500 ft) a.s.l. and drifted NW, W, and SW. On 30 July, explosions and noises resembling blocks rolling down the flanks were reported. Incandescence at the crater was noted on 31 July. On 31 July and 3 and 4 August blocks rolled up to 1 km down the flanks and ashfall was reported in areas to the SW and W. During 3-4 August, roaring noises were reported in multiple areas. On 4 August an explosion produced an ash plume that rose to an altitude of 13 km (42,700 ft) a.s.l. Intense ashfall was reported in areas W. The noise generated by the explosion was heard as far away as Ambato, 31 km NW. Source: Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN)

Weekly Reports Archive

Since the Weekly Volcanic Activity Report began in November 2000, there have been 20,652 individual reports over 1,244 weeks (average of 17 per week) on 338 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)