All times are local unless otherwise stated.

Fuego | 23 May-29 May 2012 | New Activity / Unrest Cite this Report
Fuego South-Central Guatemala	INSIVUMEH reported that during 22-23 May explosions from Fuego produced ash plumes that rose 700 m above the crater and drifted W and SW. Explosions produced shock waves and rumbling noises, and avalanches descended the SW flank towards the Ceniza drainage. Seismic data suggested that on 25 May lava was emitted in the crater, although lava flows were not observed the previous few days. Plumes rose 2 km above the crater and drifted SE, SW, and W. Ashfall was reported in Sangre de Cristo (8 km WSW), Yepocapa (8 km WNW), and in the department of Chimaltenango (21 km NNE). A pyroclastic flow traveled SW down the Las Lajas drainage. During 26-29 May explosions produced ash plumes that rose as high as 1 km above the crater and drifted N, NE, S, and SE. A lava flow traveled 200 m SW and avalanches from the lava-flow front traveled 300 m during 26-27 May. Pulses of incandescence 100 m high were observed during 28-29 May. Sources: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH), Coordinadora Nacional para la Reducción de Desastres (CONRED)
Galunggung | 23 May-29 May 2012 | New Activity / Unrest Cite this Report
Galunggung Western Java	CVGHM reported that, since the Alert Level was raised on 12 February, seismic activity at Galunggung had drastically decreased through 27 May. During 27 April-27 May plants around the crater area looked green and lush, small fish were swimming in the water, and insects around the crater were active. Based on seismic data, crater lake water temperature and pH data, and visual observations, CVGHM lowered the Alert Level from 2 to 1 (on a scale of 1-4) on 28 May. Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
Nevado del Ruiz | 23 May-29 May 2012 | New Activity / Unrest Cite this Report
Nevado del Ruiz Colombia	According to INGEOMINAS, the Observatorio Vulcanológico and Sismológico de Manizales reported that on 22 May a seismic signal possibly indicated an ash emission from Nevado del Ruiz, though it was not confirmed due to poor weather conditions. On 29 May activity significantly increased; at 0307 seismic signals indicated ash emissions that were confirmed by officials and residents near the volcano as well as with a web camera. The Alert Level was raised to II (Orange; "eruption likely within days or weeks"). A gas-and-ash plume rose 1 km above the crater and ashfall was reported in Anserma (65 km NW), Aranzazu (45 km NNW), Chinchiná (30 km WNW), Dosquebradas (40 km W), Filadelfia, La Merced (60 km NNW), Manizales (30 km NW), Marmato (70 km NNW), Neira (37 km NW), Palestina (40 km WNW), Pereira (40 km WSW), Risaralda (78 km WNW), Salamina (60 km NNW), San José (56 km NW), Santagueda (40 km NW), Santa Rosa de Cabal (33 km W), Supia (72 km NNW), Villamaria (28 km NW), and Viterbo (65 km WNW). Ash also fell in all municipalities in the department of Risaralda (76 km WNW) and El Aguila (85 km W, N of Valle del Cauca). Sulfur dioxide plumes were detected by satellite and a sulfur dioxide odor was reported in multiple towns. Later that day ash emissions rose 600 m above the crater. Source: Servicio Geológico Colombiano (SGC)
Sirung | 23 May-29 May 2012 | New Activity / Unrest Cite this Report
Sirung Pantar Island	CVGHM reported that during 13-18 May diffuse white plumes from Sirung rose 10-50 m above the crater. Seismicity was elevated during 12-17 May then decreased through 23 May, although levels remained above background. On 25 May the Alert Level was lowered to 2 (on a scale of 1-4). Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
Soputan | 23 May-29 May 2012 | New Activity / Unrest Cite this Report
Soputan Sulawesi	CVGHM reported that observers in the village of Maliku noted that during 21-27 May white plumes rose 50-150 m above the crater of Soputan. Seismicity increased significantly on 25 May. CVGHM raised the Alert Level to 3 (on a scale of 1-4) on 28 May based on visual observations and increased seismicity. Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)

Aira | 23 May-29 May 2012 | Continuing ActivityCite this Report
Aira Kyushu (Japan)	JMA reported eight explosive eruptions from Sakura-jima's Showa Crater during 21-25 May and a small eruption from Minami-dake Crater on 23 May. Based on information from JMA, the Tokyo VAAC reported that during 23-24 and 26-28 May explosions produced plumes that rose to altitudes of 1.8-4.6 km (6,000-15,000 ft) a.s.l. and drifted SW, S, SE, E, and NE. Sources: Japan Meteorological Agency (JMA), Tokyo Volcanic Ash Advisory Center (VAAC)
Bagana | 23 May-29 May 2012 | Continuing ActivityCite this Report
Bagana Bougainville (Papua New Guinea)	According to NASA's Earth Observatory, a satellite image of Bagana acquired on 16 May showed a lava flow on the E flank. Other satellite images indicated that the lava flow was emplaced sometime between March 2011 and February 2012. A plume drifted W. Source: NASA Earth Observatory
Cleveland | 23 May-29 May 2012 | Continuing ActivityCite this Report
Cleveland Chuginadak Island (USA)	AVO reported that during 23-29 May satellite observations of Cleveland's summit crater revealed nothing unusual; no ash emissions or other signs of unrest were detected or reported. The Volcano Alert Level remained at Watch and the Aviation Color Code remained at Orange. Source: US Geological Survey Alaska Volcano Observatory (AVO)
Dukono | 23 May-29 May 2012 | Continuing ActivityCite this Report
Dukono Halmahera	Based on analyses of satellite imagery, the Darwin VAAC reported that on 25 May an ash plume from Dukono rose to an altitude of 4.5 km (14,000 ft) a.s.l. and drifted 185 km E. Ash plumes again rose to an altitude of 4.5 km (14,000 ft) a.s.l. drifting 130 km E on 27 May and 93 km NE on 28 May. An ash plume rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted 75 km NE during 28-29 May. Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Karymsky | 23 May-29 May 2012 | Continuing ActivityCite this Report
Karymsky Eastern Kamchatka (Russia)	KVERT reported that moderate seismic activity from Karymsky continued to be detected during 18-25 May, and indicated that possible ash plumes rose to an altitude of 2.2 km (7,200 ft) a.s.l. on 17 and 19 May. Satellite imagery showed a thermal anomaly on the volcano during 17-18, 20, 22, and 24 May. The Aviation Color Code remained at Orange. Based on information from the Yelizovo Airport (UHPP) and analyses of satellite imagery, the Tokyo VAAC reported that on 27 May an ash plume drifted NE at an altitude of 3 km (10,000 ft) a.s.l. Sources: Tokyo Volcanic Ash Advisory Center (VAAC), Kamchatkan Volcanic Eruption Response Team (KVERT)
Kilauea | 23 May-29 May 2012 | Continuing ActivityCite this Report
Kilauea Hawaiian Islands (USA)	During 23-29 May HVO reported that the circulating and spattering lava lake periodically rose and fell in the deep pit within Kilauea's Halema'uma'u Crater. Parts of the inner ledge and crater wall surrounding the lake occasionally collapsed into the lake. Almost daily measurements indicated that the gas plume from the vent continued to deposit variable amounts of ash, Pele's hair, and occasionally fresh spatter from the margins of the lava lake, onto nearby areas. The level of the lava pond in a small pit on the E edge of Pu'u 'O'o crater floor dropped out of view. A small lava flow erupted from a vent on the S part of the floor on 23 May. On 28 May HVO noted that lava-flow activity on the coastal plain SE of Pu'u 'O'o appeared to have stopped. Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
Popocatepetl | 23 May-29 May 2012 | Continuing ActivityCite this Report
Popocatepetl Mexico	CENAPRED reported that during 23-29 May gas-and-ash plumes from Popocatépetl rose up to 2 km above the crater and drifted in multiple directions. Cloud cover occasionally prevented observations of the plumes. Ashfall was reported in San Pedro Benito Juarez (10-12 km SE) and Huejotzingo (27 km NE) on 23 May, and in Atlixco (23 km SE) and San Pedro Benito Juarez on 25 May. Incandescent fragments ejected from the crater landed on the flanks during 23-26 May. Incandescence from the crater was visible on 27 May. The Alert Level remained at Yellow Phase Three. Source: Centro Nacional de Prevencion de Desastres (CENAPRED)
Sangay | 23 May-29 May 2012 | Continuing ActivityCite this Report
Sangay Ecuador	Based on a SIGMET report, the Washington VAAC reported a possible eruption and ash plume from Sangay on 28 May. A later notice stated that a pilot reported an ash plume at an altitude of 6.1 km (20,000 ft) a.s.l. Ash was not identified in satellite imagery. Source: Washington Volcanic Ash Advisory Center (VAAC)
Santa Maria | 23 May-29 May 2012 | Continuing ActivityCite this Report
Santa Maria Southwestern Guatemala	INSIVUMEH reported that during 22-23 and 28-29 May explosions from Santa María's Santiaguito lava-dome complex produced ash plumes that rose 400-900 m above Caliente dome and drifted E, SE, and S. During 26-27 May explosions produced ash plumes that drifted W. Avalanches were generated by the W part of the lava dome and from lava flows. On 29 May lahars traveled S down the Rio Nima I and San Isidro drainages, carrying tree branches and blocks 1-1.5 m in diameter. Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Sheveluch | 23 May-29 May 2012 | Continuing ActivityCite this Report
Sheveluch Central Kamchatka (Russia)	KVERT reported that during 18-25 May explosive activity at Shiveluch continued and a thermal anomaly was observed daily in satellite imagery. Ground-based observers and satellite imagery indicated that a viscous lava flow continued to effuse in the active crater, and was accompanied by fumarolic activity and lava-dome incandescence. On 19 May seismic data indicated that possible ash plumes rose to an altitude of 9.5 km (31,200 ft) a.s.l. On 20 May observers noted ash plumes rising to altitudes of 8-9 km (26,200-29,500 ft) a.s.l.; satellite images showed ash plumes drifting 410 km SW. The Aviation Color Code remained at Orange. Based on information from KVERT and KEMSD, and analyses of satellite images, the Tokyo VAAC reported that during 26-29 May ash plumes from eruptions and possible eruptions rose to altitudes of 7-9.1 km (23,000-30,000 ft) a.s.l. and drifted SE, W, and SW. Sources: Tokyo Volcanic Ash Advisory Center (VAAC), Kamchatkan Volcanic Eruption Response Team (KVERT)
Tungurahua | 23 May-29 May 2012 | Continuing ActivityCite this Report
Tungurahua Ecuador	IG reported that during 23-24 May gas-and-ash plumes from Tungurahua drifted SW, W, and NW. Ashfall was reported in Mapayacu (SW), Puela (8 km SW), Manzano (8 km SW), Cahuají (8 km SW), and Riobamba (30 km S). An explosion detected on 25 May was accompanied by roaring and sounds resembling rolling blocks. An ash plume rose 2.5 km above the crater and drifted NW. A steam-and-gas plume rose 200 m and drifted W. Cloud cover prevented observations during 26-29 May. Ashfall was reported in Manzano and Choglontus (SW) on 29 May. Source: Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN)

Weekly Reports Archive

Since the Weekly Volcanic Activity Report began in November 2000, there have been 20,019 individual reports over 1,216 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)