All times are local unless otherwise stated.

Aira | 19 August-25 August 2015 | New Activity / Unrest Cite this Report
Aira Kyushu (Japan)	JMA reported that a small-scale explosion from Showa Crater (Aira Caldera’s Sakurajima volcano) occurred on 19 August. In a report from 21 August JMA noted that the possibility of larger-scale eruption had decreased since 15 August. Deformation data during 15-16 August suggested a dike intrusion beneath Minamidake Crater, centered 1-3 km below sea level, with an estimated volume of 2 million cubic meters. Small-scale explosions at Showa Crater occurred on 21 and 23 August. The Alert Level remained at 4 (on a 5-level scale). Source: Japan Meteorological Agency (JMA)
Cleveland | 19 August-25 August 2015 | New Activity / Unrest Cite this Report
Cleveland Chuginadak Island (USA)	On 21 August AVO reported that elevated surface temperatures detected at Cleveland's summit crater in satellite images during the previous few days likely indicated lava effusion. Minor steam emissions rose from the crater during 21-22 August. Elevated surface temperatures during 23-25 August were again detected. The Aviation Color Code remained at Orange and the Volcano Alert Level remained at Watch. Source: US Geological Survey Alaska Volcano Observatory (AVO)
Cotopaxi | 19 August-25 August 2015 | New Activity / Unrest Cite this Report
Cotopaxi Ecuador	IG reported that during an overflight of Cotopaxi on 18 August scientists observed continuous but variable amounts of ash and steam rising more than 100 m above the crater before descending the W flank. Significant amounts of ash were deposited on the flanks in an area from the N to the SW flanks. Several new cracks on the top of some glaciers were noted, especially on the E and NE flanks, and possible new tephra deposits on the N flank were observed. Thermal images revealed no hot material on the flanks; emissions prevented measurements of the inside of the crater. During 18-19 August emissions of steam and gas from Cotopaxi were occasionally observed during periods of clear weather. During the morning of 20 August gas plumes rose just above the crater and drifted W. The next day gas-and-steam plumes rose less than 2 km above the crater and drifted NW; cloud cover continued to sometimes prevent visual observations. On 22 August at 0426 the network detected an increase in the seismic amplitude. Steam-and-ash plumes rising 2 km from the crater were more sustained and higher compared to previous days; plumes drifted NW and WSW. Tremor began at 2141, and was accompanied by the onset of continuous ash emissions. Rangers confirmed ashfall at the entrance of Cotopaxi National Park. Throughout 23 August continuous ash emissions occurred with few breaks, rising no more than 1 km above the crater, and drifting SW. IGEPN staff found 2-mm-thick ash deposits that had accumulated during an 18-hour period. On 24 August ash deposits were noted in most of the N parts of Latacunga valley and reached the S moors of Romerillos. On 25 August ash plumes drifted WNW, causing ashfall in Machachi, Chaupi, and Tambillo. Source: Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN)
Nevado del Ruiz | 19 August-25 August 2015 | New Activity / Unrest Cite this Report
Nevado del Ruiz Colombia	On 23 August Servicio Geológico Colombiano’s (SGC) Observatorio Vulcanológico and Sismológico de Manizales reported that volcanic tremor associated with ash emissions from Nevado del Ruiz continued. Ashfall was confirmed by officials from Civil Aviation and the Parque Nacional Natural de los Nevados, as well as residents in Pereira. Earthquakes were located under the NE part of Arenas Crater, at depths between 3.5 and 5 km. The largest event was local M 2. Source: Servicio Geológico Colombiano (SGC)
Piton de la Fournaise | 19 August-25 August 2015 | New Activity / Unrest Cite this Report
Piton de la Fournaise Reunion Island (France)	On 24 August OVPDLF reported continued deformation and an increase in seismicity at Piton de la Fournaise during the previous several days, and a significant increase in seismicity that morning. Sulfur dioxide gas emissions increased at 1600, and at 1711 the seismic and deformation network indicated a magmatic intrusion. Lava fountains were visible at 1850 from a fissure on the S flank of Dolomieu Crater, at about 2000 m elevation, near Rivals Crater. The fissure propagated towards the top of Rivals, and at around 2115 a fissure opened to the NW, below Bory Crater. The lava-flow rate was 30-60 cubic meters per second. By the next morning fountains at higher elevations ceased, and were only active from a 100-m-long section near Rivals Crater. The lava flow rate had significantly decreased to 10 cubic meters per second. Near the top of the active fissure a 140-m-high cone had formed. Source: Observatoire Volcanologique du Piton de la Fournaise (OVPF)

Ambrym | 19 August-25 August 2015 | Continuing ActivityCite this Report
Ambrym Vanuatu	On 21 August the Vanuatu Geohazards Observatory issued a statement reminding residents and visitors that Ambrym remained active; the Alert Level remained at 2 (on a scale of 0-5). Areas deemed hazardous were near and around the active vents (Benbow, Maben-Mbwelesu, Niri-Mbwelesu and Mbwelesu), and in downwind areas prone to ashfall. Source: Vanuatu Meteorology and Geohazards Department (VMGD)
Barren Island | 19 August-25 August 2015 | Continuing ActivityCite this Report
Barren Island Andaman Islands (India)	Based on analysis of satellite imagery and wind data, the Darwin VAAC reported that on 19 August ash plumes from Barren Island rose to an altitude of 1.5 km (5,000 ft) a.s.l. and drifted 55 km E. Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Calbuco | 19 August-25 August 2015 | Continuing ActivityCite this Report
Calbuco Southern Chile	According to the civil protection agency, ONEMI, on 18 August OVDAS-SERNAGEOMIN reported that seismicity at Calbuco fluctuated at low levels and continued to decline, and only water vapor emissions rose from the vents. The Alert Level was lowered to Green (the lowest level on a four-color scale). ONEMI maintained an elevated Alert Level of Yellow (mid-level on a 3-color scale) for the Llanquihue and Puerto Octay provinces, and an Alert Level Green for Puerto Montt and Puerto Varas. On 21 August the 10-km exclusion zone around the volcano was lifted, but SERNAGEOMIN warned that the 1.5 km exclusion zone around the craters remained in effect and the public should continue to stay away from drainages. Source: Oficina Nacional de Emergencia-Ministerio del Interior (ONEMI)
Colima | 19 August-25 August 2015 | Continuing ActivityCite this Report
Colima Mexico	Based on satellite images, webcam views, and notices from the Mexico City MWO, Colima Observatory, and Jalisco civil protection agency, the Washington VAAC reported that during 20-21 and 24 August ash-and-gas plumes from Colima rose to altitudes of 4.2-7 km (14,000-23,000 ft) a.s.l. and drifted W, WNW, NW, NE, and SE. On 18 August an ash plume rose to an altitude of 5.2 km (17,000 ft) a.s.l. and slowly drifted W. Source: Washington Volcanic Ash Advisory Center (VAAC)
Dukono | 19 August-25 August 2015 | Continuing ActivityCite this Report
Dukono Halmahera	Based on analyses of satellite imagery and wind data, the Darwin VAAC reported that during 19-21 and 25-26 August ash plumes from Dukono rose to altitudes of 2.1-2.4 km (7,000-8,000 ft) a.s.l. and drifted 45-110 km W, WNW, NE, and E. Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Fuego | 19 August-25 August 2015 | Continuing ActivityCite this Report
Fuego South-Central Guatemala	INSIVUMEH reported that during 22-25 August explosions at Fuego produced booming noises, and ash plumes that rose 450-650 m above the crater and drifted 12 km W. Incandescent material was ejected 100-150 m above the crater. Ashfall was reported in Panimaché (8 km SW), Morelia (9 km SW), and Santa Sofía (12 km SW). Lahars descended the Trinidad drainage (S). Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Karymsky | 19 August-25 August 2015 | Continuing ActivityCite this Report
Karymsky Eastern Kamchatka (Russia)	KVERT reported that moderate explosive activity at Karymsky continued during 14-21 August. Satellite images detected ash plumes drifting 54 km SE on 15 August, and a thermal anomaly on the volcano during 15 and 18-20 August. The Aviation Color Code remained at Orange. Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Kilauea | 19 August-25 August 2015 | Continuing ActivityCite this Report
Kilauea Hawaiian Islands (USA)	HVO reported that seismicity at Kilauea remained at background levels during 19-25 August. The lava lake continued to circulate and spatter in the Overlook vent. Webcams recorded multiple incandescent outgassing vents within Pu'u 'O'o. The June 27th NE-trending lava flow continued to be active in three areas with surface flows within 4-8 km NE of Pu'u 'O'o Crater; smoke plumes from burning vegetation marked the most distal flows. Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
Manam | 19 August-25 August 2015 | Continuing ActivityCite this Report
Manam Northeast of New Guinea	Based on observations of satellite imagery and wind data analyses, the Darwin VAAC reported that during 21-22 August minor ash plumes from Manam rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted 10-75 km NW and ESE. Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Raung | 19 August-25 August 2015 | Continuing ActivityCite this Report
Raung Eastern Java	PVMBG reported that ash plumes from Raung rose as high as 1 km above the crater during 16-24 August and drifted NW. Seismicity fluctuated but continued to decrease. The Alert Level was lowered to 2 (on a scale of 1-4) on 24 August, and the public was reminded not to approach the crater within a 2-km radius. Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
Reventador | 19 August-25 August 2015 | Continuing ActivityCite this Report
Reventador Ecuador	During 19-25 August IG reported a high level of seismic activity including explosions, tremor, long-period earthquakes, harmonic tremor, and signals indicating emissions at Reventador; cloud cover often prevented visual observations. On 20 August a steam-and-ash plume rose 2 km and drifted S and SW. During 23-24 August steam-and-ash plumes rose 500-700 m and drifted NW. Source: Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN)
Santa Maria | 19 August-25 August 2015 | Continuing ActivityCite this Report
Santa Maria Southwestern Guatemala	INSIVUMEH reported that during 23-25 August explosions from Caliente cone, part of Santa María's Santiaguito lava-dome complex, generated an ash plume that rose 700-800 m and drifted W and SW. Block avalanches from lava-flow fronts descended the E flanks. Ashfall was reported in Aldea, San Marcos (10 km SW), and Palajunoj (18 km SSW). Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Sheveluch | 19 August-25 August 2015 | Continuing ActivityCite this Report
Sheveluch Central Kamchatka (Russia)	KVERT reported that during 14-21 August lava-dome extrusion onto Sheveluch’s N flank was accompanied by fumarolic activity, dome incandescence, and hot avalanches. Satellite images detected a daily thermal anomaly over the dome. The Aviation Color Code remained at Orange. Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Shishaldin | 19 August-25 August 2015 | Continuing ActivityCite this Report
Shishaldin Fox Islands (USA)	AVO reported that on 18 August a field crew conducting gas measurements at Shishaldin observed a low-level plume from the summit drifting several kilometers downwind. Seismicity continued to be elevated over background levels during 19-25 August indicating that low-level eruptive activity confined to the summit crater continued. Cloud cover mostly prevented satellite and webcam observations; elevated surface temperatures were occasionally detected in satellite images. The Aviation Color Code remained at Orange and the Volcano Alert Level remained at Watch. Source: US Geological Survey Alaska Volcano Observatory (AVO)
Suwanosejima | 19 August-25 August 2015 | Continuing ActivityCite this Report
Suwanosejima Ryukyu Islands (Japan)	Based on JMA notices and satellite-image analyses, the Tokyo VAAC reported that on 21 August ash plumes from Suwanosejima rose to an altitude of 1.8 km (6,000 ft) a.s.l. and drifted SE. Source: Japan Meteorological Agency (JMA)
Tongariro | 19 August-25 August 2015 | Continuing ActivityCite this Report
Tongariro North Island (New Zealand)	On 19 August GeoNet reported that activity at Tongariro's Te Maari Craters had declined significantly since the eruption in 2012, with data suggesting that unrest associated with the eruption was over. The Volcanic Alert Level was lowered to 0 (on a scale of 0-5). The Volcanic Alert Level for Ngauruhoe is separate and had been lowered to 0 on 20 April. Source: GeoNet
Tungurahua | 19 August-25 August 2015 | Continuing ActivityCite this Report
Tungurahua Ecuador	IG reported moderate-to-high seismic activity at Tungurahua during 19-25 August, characterized by long-period events and volcano-tectonic events. Cloud cover often prevented visual observations. On 22 August water-vapor plumes with moderate amounts of ash drifted W. A small, reddish ash emission drifted W the next day. Five explosions on 25 August were felt by surrounding communities and generated ash plumes that rose 2 km. Ashfall was reported in Chontapamba (W), Bilbao (8 km W), Juive (7 km NNW), and Pillate (8 km W). Source: Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN)

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.

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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)