All times are local unless otherwise stated.

Aira | 23 September-29 September 2015 | New Activity / UnrestCite this Report
Aira Kyushu (Japan)	JMA reported that during 21-28 September emissions rose from both Showa Crater and Minami-Dake Crater at Aira Caldera’s Sakurajima volcano. An explosion at Minami-Dake Crater at 0233 on 28 September generated a plume that rose 2.7 km above the crater. The Alert Level remained at 3 (on a 5-level scale). Source: Japan Meteorological Agency (JMA)
Nevado del Ruiz | 23 September-29 September 2015 | New Activity / UnrestCite this Report
Nevado del Ruiz Colombia	Servicio Geológico Colombiano’s (SGC) Observatorio Vulcanológico y Sismológico de Manizales reported that during 22-28 September seismicity at Nevado del Ruiz was characterized by long-period earthquakes and short-duration volcanic tremor associated with gas-and-ash emissions. Earthquakes occurred at depths between 1.3 and 7.5 km. The largest event was recorded at 1027 on 22 September, a local M 1.1, near Arenas Crater at a depth of 4 km. Water-vapor, gas, and ash plumes rose 2 km above the crater and drifted mainly NW. Thermal anomalies over the crater were sometimes detected in satellite images; a significant anomaly was detected on 26 September. A pulse of tremor at 1633 on 28 September was accompanied by an ash emission that drifted E and W. The Alert Level remained at III (Yellow; "changes in the behavior of volcanic activity"). Source: Servicio Geológico Colombiano (SGC)
Piton de la Fournaise | 23 September-29 September 2015 | New Activity / UnrestCite this Report
Piton de la Fournaise Reunion Island (France)	On 24 September OVPDLF reported that, since 20 September, seismicity, deformation, and gas emissions at Piton de la Fournaise stabilized but remained at high levels. The cone was 30 m high; lava fountains were lower and less frequently observed. A white water vapor plume rose from the vents. Lava flows continued to be active, mainly traveling as far as 3 km S and less than 3 km E. During 22-23 September a new lava tube formed to the W of the lava field. Since the beginning of the eruption deformation data indicated no deflation. Early on in the eruption the flow rate decreased from 60 cubic meters per second to between 5 and 10; the rate declined during 28 August-7 September and then increased again, starting on 7 September. Source: Observatoire Volcanologique du Piton de la Fournaise (OVPF)
Telica | 23 September-29 September 2015 | New Activity / UnrestCite this Report
Telica Sierra de los Marrabios	INETER reported that a 30-minute period of moderate-intensity explosions at Telica began at 0800 on 23 September. Abundant gas-and-ash emissions initially rose 400 m above the crater and drifted WNW, but then decreased to 50 m. Ashfall was reported in the community of Guanacastal. Explosions occurred at 1645 and 1648. Scientists conducting fieldwork observed deposits on the crater floor from an inner-wall landslide that had occurred on 17 July, and new fumaroles on the crater floor. Five explosions were detected on 24 September. Based on wind and satellite data, the Washington VAAC reported that on 26 September ash plumes rose as high as 3.6 km (12,000 ft) a.s.l. and drifted W and N. During 28-29 September INETER noted that voluminous gas plumes rose from two vents on the crater floor. Sources: Instituto Nicaragüense de Estudios Territoriales (INETER), Washington Volcanic Ash Advisory Center (VAAC)

Bagana | 23 September-29 September 2015 | Continuing ActivityCite this Report
Bagana Bougainville (Papua New Guinea)	Based on analyses of satellite imagery and wind data, the Darwin VAAC reported that during 24 and 26-27 September ash plumes from Bagana rose to altitudes of 1.8-2.4 km (6,000-8,000 ft) a.s.l. and drifted 35-100 km N, NE, E, and SE. Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Barren Island | 23 September-29 September 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 22 September an ash plume from Barren Island rose to an altitude of 1.8 km (6,000 ft) a.s.l. and drifted 45 km E. Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Cleveland | 23 September-29 September 2015 | Continuing ActivityCite this Report
Cleveland Chuginadak Island (USA)	AVO reported that during 23-29 September low-level unrest at Cleveland likely continued. The Aviation Color Code remained at Orange and the Volcano Alert Level remained at Watch. Source: US Geological Survey Alaska Volcano Observatory (AVO)
Colima | 23 September-29 September 2015 | Continuing ActivityCite this Report
Colima Mexico	Based on satellite images, wind data, and webcam views, the Washington VAAC reported that on 22 September ash plumes from Colima drifted over 15 km W and SW. On 23 September ash plumes rose to altitudes of 6.7-7 km (22,000-23,000 ft) a.s.l., drifted SW, and dissipated near the coast. Ash plumes the next day drifted 15-30 km WSW. Source: Washington Volcanic Ash Advisory Center (VAAC)
Cotopaxi | 23 September-29 September 2015 | Continuing ActivityCite this Report
Cotopaxi Ecuador	During an overflight of Cotopaxi on 22 September, IG scientists observed low-energy emissions with low or no ash content that rose 500 m above the crater and drifted W. Fracturing continued on both the upper parts of the glacier and the glacial toes on the N, NW, and SW flanks. The glacier inside the crater had almost disappeared. Several areas of landslide deposits inside and outside of the crater were noted. Yellowish-green deposits from increased fumarolic activity were most apparent on the S, SE, and E flanks. Thermal images revealed temperature decreases since the previous overflight at the new vents inside the crater and at areas on the S flank. During 23-29 September gas-and-water vapor plumes, often with low ash content, rose as high as 2 km and drifted mainly W and SW. Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)
Dukono | 23 September-29 September 2015 | Continuing ActivityCite this Report
Dukono Halmahera	Based on analyses of satellite imagery and wind data, the Darwin VAAC reported that during 23-27 September ash plumes from Dukono rose to altitudes of 1.5-2.4 km (5,000-8,000 ft) a.s.l. and drifted 45-110 km NW, N, and NE. Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Karymsky | 23 September-29 September 2015 | Continuing ActivityCite this Report
Karymsky Eastern Kamchatka (Russia)	KVERT reported that moderate explosive activity at Karymsky continued during 18-25 September. Satellite images detected a thermal anomaly on the volcano on 18 and 24 September, and an ash plume that drifted 10 km NE on 20 September. The Aviation Color Code remained at Orange. Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Kilauea | 23 September-29 September 2015 | Continuing ActivityCite this Report
Kilauea Hawaiian Islands (USA)	HVO reported that seismicity beneath Kilauea's summit, upper East Rift Zone, and Southwest Rift Zone was at background levels during 23-29 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. A small lava pond, not visible with the webcams, remained active in a pit on the W side of the crater floor. Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
Raung | 23 September-29 September 2015 | Continuing ActivityCite this Report
Raung Eastern Java	PVMBG reported that, although inclement weather conditions often prevented visual observations of Raung during 25 August-21 September, white plumes were occasionally seen rising as high as 200 m above the crater. Seismicity fluctuated but continued to decrease. The Alert Level remained at 2 (on a scale of 1-4), 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 | 23 September-29 September 2015 | Continuing ActivityCite this Report
Reventador Ecuador	During 23-29 September IG reported a high level of seismic activity including explosions, volcano-tectonic events, long-period earthquakes, harmonic tremor, and signals indicating emissions at Reventador; cloud cover often prevented visual observations. Daily ash-and-gas emissions rose as high as 1.5 km above the crater and drifted W, WNW, and NW. Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)
Santa Maria | 23 September-29 September 2015 | Continuing ActivityCite this Report
Santa Maria Southwestern Guatemala	Based on Observatorio del volcán Santiaguito (OVSAN) observations, INSIVUMEH reported that on 29 September explosions from Santa María's Santiaguito lava-dome complex generated multiple small pyroclastic flows. The largest pyroclastic flow traveled 4 km E down the Ángel and Nimá I drainages. Dense ash plumes drifted E causing ashfall in areas between Quetzaltenango (18 km WNW) and El Palmar (12 km S). Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Sheveluch | 23 September-29 September 2015 | Continuing ActivityCite this Report
Sheveluch Central Kamchatka (Russia)	KVERT reported that during 18-25 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 | 23 September-29 September 2015 | Continuing ActivityCite this Report
Shishaldin Fox Islands (USA)	AVO reported that seismicity at Shishaldin continued to be elevated over background levels during 23-29 September, indicating that low-level eruptive activity confined to the summit crater continued. Cloud cover often prevented satellite and webcam observations; weakly elevated surface temperatures were detected in satellite images on 23 September. The Aviation Color Code remained at Orange and the Volcano Alert Level remained at Watch. Source: US Geological Survey Alaska Volcano Observatory (AVO)
Sinabung | 23 September-29 September 2015 | Continuing ActivityCite this Report
Sinabung Northwestern Sumatra	PVMBG reported that during 14-24 September foggy weather sometimes prevented visual observations of Sinabung and the growing lava dome in the summit crater. Lava flows on the flanks were incandescent as far as 2 km E to SE. As many as eight pyroclastic flows per day were detected, traveling as far as 4 km ESE. Ash plumes rose as high as 4.5 km. Seismicity consisted of avalanche signals, low-frequency and hybrid events, tremor, tectonic events, and volcanic earthquakes. Seismicity fluctuated at high levels, although it had declined compared to the previous week. The Alert Level remained at 4 (on a scale of 1-4), indicating that people within 7 km of the volcano on the SSE sector, and within 6 km in the ESE sector, should evacuate. Based on information from PVMBG, the Darwin VAAC reported that during 26-27 September ash plumes rose 1-2.5 km. Sources: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM), Darwin Volcanic Ash Advisory Centre (VAAC)
Tungurahua | 23 September-29 September 2015 | Continuing ActivityCite this Report
Tungurahua Ecuador	In a special report from 21 September, IG noted increased activity at Tungurahua during the previous two weeks, characterized by an increase in seismicity and the intensity of gas-and-ash emissions. An explosion on 19 September generated an ash plume that rose 2 km. Later that night weak glow from the crater was observed. Moderate levels of activity at Tungurahua were reported during 23-29 September; inclement weather often prevented visual observations. Seismicity significantly increased on 26 September, accompanied by emissions with high ash content that rose 500 m and ejected incandescent blocks that rolled 500 m down the NW flank. Ashfall was reported in Manzanó (8 km SW), Choglontus (13 km WSW), Caguají, and Palitahua (6 km SSW). 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.

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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)