All times are local unless otherwise stated.

Aira (Japan) | 2 September-8 September 2015 | New Activity / Unrest Cite this Report
Aira Ryukyu Volcanic Arc	JMA reported 30 explosions during 31 August-7 September from Showa Crater at Aira Caldera’s Sakurajima volcano, some that ejected tephra as far as 1,300 m, and incandescence from the crater that was occasionally visible at night. The Alert Level remained at 3 (on a 5-level scale). Source: Japan Meteorological Agency (JMA)
Axial Seamount (Undersea Features) | 2 September-8 September 2015 | New Activity / Unrest Cite this Report
Axial Seamount Northeast Pacific Rifts Volcanic Province	An eruption at Axial Seamount, inferred to have started at 2230 on 23 April with an earthquake swarm, was confirmed during 14-29 August by bathymetric data and observations made during a ROV Jason dive. Two large lava flows from the N rift zone (8-16 km N of the summit caldera) were at most 127 m thick; some of the thicker areas had drained collapse features indicating they had molten interiors when emplaced. The ROV traversed the flows for about 2 km. New, thinner lava flows were also identified in the NE summit caldera and on the NE rim. Source: Oregon State University's Marine Science Center and NOAA/PMEL EOI Program
Cotopaxi (Ecuador) | 2 September-8 September 2015 | New Activity / Unrest Cite this Report
Cotopaxi Northern Andean Volcanic Arc	IG reported that during the morning on 2 September gas-and-steam plumes from Cotopaxi contained minor amounts of ash, rose 100 m above the crater, and drifted W and NW. At about 1318, plumes with moderate amounts of ash rose 4 km and drifted W. Ashfall was reported in Machachi, Aloasí, and Chaupi. Analysis of ash collected on 2 September showed that the greatest contribution of material was pre-existing and altered rock. On 3 September ash-and-water-vapor plumes rose 2.2 km and drifted N and NW. During an overflight scientists observed ash emissions that rose 1 km and drifted W then N; the plume continued to rise to 8.5 km as it drifted N. Several new cracks in the glaciers were noted, especially on the E and NE flanks. Blocks had been deposited on the N and S parts of the crater. The circular glacier at the top of the inside part of the crater had significantly decreased in size and had large fractures. Glacial melting on the upper flanks had also accelerated. Streams of meltwater were present on the N flank. Thermal images revealed temperature increases in the S and E parts of the crater and a significant increase in temperatures of emissions (200 degrees Celsius). Seismic amplitudes did not increase but signals 3-11 km deep aligned with the conduit suggested rising magma. Bright areas at the summit were observed at night, possibly from hot block deposits. During 4-8 September gas-and-ash plumes rose 1 km at most and drifted N and NW. Source: Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN)
Nevado del Ruiz (Colombia) | 2 September-8 September 2015 | New Activity / Unrest Cite this Report
Nevado del Ruiz Northern Andean Volcanic Arc	Servicio Geológico Colombiano’s (SGC) Observatorio Vulcanológico and Sismológico de Manizales reported that during 1-7 September seismicity at Nevado del Ruiz was characterized by long-period earthquakes and short-duration volcanic tremor associated with gas-and-ash emissions. In addition, volcano-tectonic (VT) events occurred at depths between 0.4 and 6.4 km. The largest VT event was recorded at 0017 on 2 September, was a local M 1.4, and was 1.5 km NE of Arenas Crater at a depth of 3.8 km. Incandescence was recorded by a webcam installed near the volcano. Water-vapor-and-gas plumes rose 1.4 km above the crater and drifted NW, and were sometimes tinged gray due to the presence of ash. Ashfall was reported in Manizales (30 km NW) and Pereira (40 km WSW). The Alert Level remained at III (Yellow; "changes in the behavior of volcanic activity"). Sources: Servicio Geológico Colombiano (SGC), La Patria
Piton de la Fournaise (France) | 2 September-8 September 2015 | New Activity / Unrest Cite this Report
Piton de la Fournaise Reunion Hotspot Volcano Group	OVPDLF reported that scientists conducting fieldwork at Piton de la Fournaise during 31 August-1 September observed one active cone (20 m high) filled with a lava lake. Fluctuating lava fountains rose 15-20 m above the lake surface and gas bubbles exploded. Lava traveled through a 50-m-long lava channel and was a total of 1 km long. During 1-2 September seismicity increased, and the lava flow length increased to 2 km. Tremor remained high on 5 September. The lava lake was in two separate but side-by-side vents and lava fountains were lower compared to recent days. Five small lava flows were near the foot of the cone; four were 30 m long and the fifth was 1 km long. Tremor levels started to decline on 7 September but remained at a high level through 9 September. Source: Observatoire Volcanologique du Piton de la Fournaise (OVPF)

Asosan (Japan) | 2 September-8 September 2015 | Continuing ActivityCite this Report
Asosan Nankai Volcanic Arc	JMA reported that on 3 September a small-scale eruption from Asosan’s Nakadake Crater generated a whitish plume that rose 200 m above the crater. During fieldwork later that day, scientists confirmed that the event originated in the SW part of the crater and minor ashfall had occurred. A white plume rose 400 m on 7 September. The Alert Level remained at 2 (on a scale of 1-5). Source: Japan Meteorological Agency (JMA)
Cleveland (United States) | 2 September-8 September 2015 | Continuing ActivityCite this Report
Cleveland Aleutian Ridge Volcanic Arc	AVO reported that during 2-3 September a few very small earthquakes were detected at Cleveland. During 5-7 September elevated surface temperatures were detected in satellite images. Steaming from the summit was recorded by the webcam on 5 September. The next day satellite and webcam images showed a low-level gas-and-steam plume over the volcano. A robust steam plume was visible on 8 September. The Aviation Color Code remained at Orange and the Volcano Alert Level remained at Watch. Source: US Geological Survey Alaska Volcano Observatory (AVO)
Colima (Mexico) | 2 September-8 September 2015 | Continuing ActivityCite this Report
Colima Trans-Mexican Volcanic Belt	Based on satellite images, the Washington VAAC reported that on 5 September a gas-and-ash plume from Colima rose to an altitude of 6.1 km (20,000 ft) a.s.l. and drifted 60 km NW. Source: Washington Volcanic Ash Advisory Center (VAAC)
Dukono (Indonesia) | 2 September-8 September 2015 | Continuing ActivityCite this Report
Dukono Halmahera Volcanic Arc	Based on analyses of satellite imagery and wind data, the Darwin VAAC reported that during 2-7 September ash plumes from Dukono rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted 35-165 km W, NW, N, NE, E, and SE. Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Fuego (Guatemala) | 2 September-8 September 2015 | Continuing ActivityCite this Report
Fuego Central America Volcanic Arc	INSIVUMEH reported that during 1-2 September activity at Fuego was characterized by lava fountains, explosions, and ashfall in surrounding areas. Pyroclastic flows descended the flanks. An ash plume rose 1.3 km above the crater and drifted 15 km W. Ashfall was reported in San Pedro Yepocapa (8 km N) and Chimaltenango (21 km NNE), and in the communities of Panimaché (8 km SW), Morelia (9 km SW), Santa Sofía (12 km SW), and Sangre de Cristo (8 km WSW). Activity decreased by the afternoon of 2 September; remnants of three lava flows were visible in the Santa Teresa (S), Trinidad (S) and Las Lajas (SE) drainages. Weak explosions during 4-5 September generated ash plumes that rose 450 m and drifted 7 km W and SE. Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Gamalama (Indonesia) | 2 September-8 September 2015 | Continuing ActivityCite this Report
Gamalama Halmahera Volcanic Arc	Based on satellite images, information from PVMBG, and wind data, the Darwin VAAC reported that on 8 September an ash plume from Gamalama rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted over 25 km NE. Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Karymsky (Russia) | 2 September-8 September 2015 | Continuing ActivityCite this Report
Karymsky Eastern Kamchatka Volcanic Arc	KVERT reported that moderate explosive activity at Karymsky continued during 28 August-4 September. Satellite images detected a thermal anomaly on the volcano on 2 September. The Aviation Color Code remained at Orange. Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Kilauea (United States) | 2 September-8 September 2015 | Continuing ActivityCite this Report
Kilauea Hawaiian-Emperor Hotspot Volcano Group	HVO reported that seismicity beneath Kilauea's summit, upper East Rift Zone, and Southwest Rift Zone was at background levels during 2-8 September. The lava lake continued to circulate and spatter in the Overlook vent. The June 27th NE-trending lava flow continued to be active within 4-8 km NE of Pu'u 'O'o Crater. Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
Manam (Papua New Guinea) | 2 September-8 September 2015 | Continuing ActivityCite this Report
Manam Bismarck Volcanic Arc	Based on observations of satellite imagery and wind data analyses, the Darwin VAAC reported that on 7 September ash plumes from Manam rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted 75 km NW. Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Santa Maria (Guatemala) | 2 September-8 September 2015 | Continuing ActivityCite this Report
Santa Maria Central America Volcanic Arc	INSIVUMEH reported that on 5 September an explosion from Santa María's Santiaguito lava-dome complex generated an ash plume that rose 700 m and drifted SW. Ashfall was reported in Monte Claro (S). On 8 September heavy rainfall triggered a hot lahar that descended the Nimá I river drainage on the S flank. The lahar carried tree trunks, branches, and 1-m-wide blocks, had a strong sulfur odor, and was 20 m wide and 1.5 m deep. Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Sheveluch (Russia) | 2 September-8 September 2015 | Continuing ActivityCite this Report
Sheveluch Eastern Kamchatka Volcanic Arc	KVERT reported that during 28 August-4 September lava-dome extrusion onto Sheveluch’s N flank was accompanied by fumarolic activity, dome incandescence, and hot avalanches. Satellite images detected an almost daily thermal anomaly over the dome. The Aviation Color Code remained at Orange. Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Shishaldin (United States) | 2 September-8 September 2015 | Continuing ActivityCite this Report
Shishaldin Aleutian Ridge Volcanic Arc	AVO reported that seismicity at Shishaldin continued to be elevated over background levels during 2-8 September, indicating that low-level eruptive activity confined to the summit crater continued. Cloud cover often prevented satellite and webcam observations; elevated surface temperatures were periodically 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)
Sinabung (Indonesia) | 2 September-8 September 2015 | Continuing ActivityCite this Report
Sinabung Sunda Volcanic Arc	Based on information from PVMBG, the Darwin VAAC reported that on 2 September an ash plume from Sinabung rose 2 km above the summit. On 3 September an ash plume rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted over 35 km W. The next day an ash plume rose to an altitude of 3.7 km (12,000 ft) a.s.l. and drifted 45 km W. Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Tungurahua (Ecuador) | 2 September-8 September 2015 | Continuing ActivityCite this Report
Tungurahua Northern Andean Volcanic Arc	IG reported that on 1 September a lahar descended Tungurahua's flank, closing part of the Penipe-Riobamba road. On 2 September ash plumes rose 3 km and drifted W. The next day ashfall was reported in Quero (20 km NW), Santuario, El Rosario, La Galera, Choglontus (13 km WSW), El Manzano (8 km SW), and Pillate (8 km W). Source: Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN)
Ubinas (Peru) | 2 September-8 September 2015 | Continuing ActivityCite this Report
Ubinas Central Andean Volcanic Arc	Instituto Geofísico del Perú (IGP) Observatorio Volcanológico del Sur (OVS) reported increased seismicity at Ubinas during 1-7 September, specifically an increase in the occurrence of long-period events and hybrid signals. Tremor increased during 5-7 September. A steam plume rose 1.5 km above the base of the crater on 2 September, and ash emissions were recorded during 6-7 September. Source: Instituto Geofísico del Perú (IGP)

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)