All times are local unless otherwise stated.

Cleveland (United States) | 22 May-28 May 2013 | New Activity / Unrest Cite this Report
Cleveland Aleutian Ridge Volcanic Arc	AVO reported that during 22-23 May elevated surface temperatures over Cleveland were observed in satellite images. Clouds obscured views during 24-26 May. Slightly elevated surface temperatures, consistent with a cooling lava flow, were observed in several satellite images during 26-28 May. The Volcanic Alert Level remained at Watch and the Aviation Color Code remained at Orange. Source: US Geological Survey Alaska Volcano Observatory (AVO)
Copahue (Chile-Argentina) | 22 May-28 May 2013 | New Activity / Unrest Cite this Report
Copahue Andean Southern Volcanic Arc	OVDAS-SERNAGEOMIN reported that a gradual increase of seismicity at Copahue had been detected since 15 May. A camera recorded periodic small explosions and corresponding ash emissions, along with nighttime incandescence. On 19 May satellite images detected increased sulfur dioxide emissions, which produced a plume that rose 300 m above the crater and drifted SE. Images from 20 and 22 May showed large plumes drifting 100 km SE that appeared translucent gray, suggesting a significant presence of volcanic gases. On 23 May the Alert Level was raised to Orange. On 24 May cameras recorded white plumes that mostly rose 250-400 m; at 1900 a plume rose 1.9 km, and another drifted NE. Seismicity increased sharply during 24-25 May. The seismic network detected 8,556 low-magnitude earthquakes with an average of 356 events per hour, and a gap of a few seconds between events. Seismicity increased again during 25-26 May, with an average of 455 events per hour, and then decreased to 269 events per hour during 26-27 May. An explosion on 26 May generated crater incandescence and a plume that rose 400 m. Weather conditions often prevented views during 25-27 May. On 27 May OVDAS-SERNAGEOMIN noted that the intensity and type of seismicity observed in recent days, in conjunction with the deformation data, suggested the rise of a magmatic body to shallow depths. The Alert Level was raised to Red. According to ONEMI, the government ordered a precautionary evacuation of the 2,440 people living within a radius of 25 km. During 27-28 May seismic signals were detected at an average rate of 130 events per hour. Cloud cover prevented visual observations. ONEMI noted that 44 people had evacuated by 28 May. Sources: Servicio Nacional de Geología y Minería (SERNAGEOMIN), Oficina Nacional de Emergencia-Ministerio del Interior (ONEMI)
Gamkonora (Indonesia) | 22 May-28 May 2013 | New Activity / Unrest Cite this Report
Gamkonora Halmahera Volcanic Arc	CVGHM reported that a phreatic eruption at Gamkonora on 23 January was preceded by increased seismicity. Some types of seismic signals increased during March-April while others decreased. On 24 May seismicity indicative of shallow magma movement increased and diffuse white plumes rose 100-300 above the crater. During 25-27 May dense white-to-gray plumes rose 200-500 m above the crater. On 27 May the Alert Level was raised to 3 (on a scale of 1-4). Residents and tourists were asked not to venture near the crater within a radius of 3 km. Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
Pavlof (United States) | 22 May-28 May 2013 | New Activity / Unrest Cite this Report
Pavlof Aleutian Ridge Volcanic Arc	AVO reported that seismic tremor at Pavlof markedly declined around 1100 on 21 May, and was followed through 23 May by the detection of small discrete events, likely indicative of small explosions, by pressure sensors. Although cloud cover prevented satellite observations, elevated surface temperatures at the vent were detected. On 22 May both a pilot report and photographs indicated weak steam-and-gas emissions containing little to no ash. The eruption continued but at a lower level during 24-26 May. Neither evidence of elevated surface temperatures nor a plume were observed in partly clear satellite images during 24-25 and 27 May. Clouds obscured views on 26 May. The Volcanic Alert Level was lowered to Advisory and the Aviation Color Code was lowered to Yellow on 28 May. Source: US Geological Survey Alaska Volcano Observatory (AVO)
Popocatepetl (Mexico) | 22 May-28 May 2013 | New Activity / Unrest Cite this Report
Popocatepetl Trans-Mexican Volcanic Belt	CENAPRED reported that during 22-28 May seismicity at Popocatépetl indicated continuing gas-and-steam emissions that contained variable amounts of ash; cloud cover occasionally prevented observations, especially during 26-27 May. Incandescence from the crater was often observed at night. On 22 May an ash plume rose 2 km above the crater and drifted NE. Periods of tremor were accompanied by emissions of steam, gas, and sometimes ash. Two plumes rose 1.3 km and drifted W. Overnight incandescent tephra was ejected 300 m above the crater and rolled down the flanks. Tremor amplitude increased on 23 May, and ash emissions drifted SE, S, and SW. An explosion at 0254 ejected large fragments that landed 1.5 km away from the crater. At 1240 an explosion generated a gas-and-ash plume that rose 2.5 km. Later that day tremor decreased; periods of tremor continued to be detected through 27 May, accompanied by emissions of steam, gas and variable amounts of ash that rose 500-900 m and drifted SW. On 25 May incandescent tephra were ejected onto the highest parts of the N and NE flanks, and a gas-and-ash plume rose 2 km. An explosion at 0547 ejected incandescent tephra 1.5 km onto the NNE flank. An explosion at 1040 on 26 May generated an ash plume that rose 2 km. A small explosion was detected at 1228. On 28 May an explosion at 0503 produced an ash plume that rose more than 2 km and drifted SW, and ejected incandescent tephra 1.5 km onto the NE flank. The Alert Level remained at Yellow, Phase Three. Source: Centro Nacional de Prevencion de Desastres (CENAPRED)
Turrialba (Costa Rica) | 22 May-28 May 2013 | New Activity / Unrest Cite this Report
Turrialba Central America Volcanic Arc	OVSICORI-UNA reported that an eruption from Turrialba's West Crater on 21 May was preceded by seismic activity characterized by more than 150 volcanic earthquakes per day since 18 April. Increased gas emissions were detected on 20 May, producing a sky-blue plume visible from nearby areas. Hybrid earthquakes also increased and became numerous at 0452 on 21 May. Continuous harmonic tremor followed and then increased at 0720. Eruptions from West Crater occurred at 0830 and after 1100 from two vents which opened in January 2010 (Boca 2010, on the W wall) and January 2012 (Boca 2012, on the E wall). The eruptions generated ash plumes that rose more than 500 m; ashfall was reported in the area of Picada (N), and in San José (35 km WSW) and Heredia (38 km W) of Ipís de Guadalupe, Goicoechea (28 km WSW), la Fazio, Zetillal (43 km W), San Isidro-San Pedro de Coronado, and San Luis de Santo Domingo (28 km W). At around 1200 ash emissions ceased and seismicity decreased. Source: Observatorio Vulcanologico y Sismologico de Costa Rica-Universidad Nacional (OVSICORI-UNA)

Aira (Japan) | 22 May-28 May 2013 | Continuing ActivityCite this Report
Aira Ryukyu Volcanic Arc	JMA reported that during 20-24 May Sakura-jima's Showa Crater had eight explosions, ejecting tephra that fell at most 1.3 km from the crater. Crater incandescence was occasionally detected at night. Based on information from JMA, the Tokyo VAAC reported that during 23-26 May explosions produced plumes that rose to altitudes of 1.8-2.4 km (6,000-8,000 ft) a.s.l. and drifted E, SW, and W. On 24 May a pilot observed an ash plume that rose to an altitude of 3 km (10,000 ft) a.s.l. Sources: Japan Meteorological Agency (JMA), Toulouse Volcanic Ash Advisory Centre (VAAC)
Bagana (Papua New Guinea) | 22 May-28 May 2013 | Continuing ActivityCite this Report
Bagana Solomon Volcanic Arc	Based on analyses of satellite imagery and wind data, the Darwin VAAC reported that on 24 May an ash plume from Bagana rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted over 35 km NW and N. Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Chirinkotan (Russia) | 22 May-28 May 2013 | Continuing ActivityCite this Report
Chirinkotan Kuril Volcanic Arc	SVERT reported that steam and gas activity at Chirinkotan was observed in satellite imagery during 24-25 May. Source: Sakhalin Volcanic Eruption Response Team (SVERT)
Karymsky (Russia) | 22 May-28 May 2013 | Continuing ActivityCite this Report
Karymsky Eastern Kamchatka Volcanic Arc	KVERT reported that satellite data showed a thermal anomaly on Karymsky during 21-22 May. Technical problems prevented seismic data collection during 17-24 May. The Aviation Color Code remained at Orange. Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Kilauea (United States) | 22 May-28 May 2013 | Continuing ActivityCite this Report
Kilauea Hawaiian-Emperor Hotspot Volcano Group	During 22-28 May HVO reported that the circulating lava lake occasionally rose and fell in the deep pit within Kilauea's Halema'uma'u Crater. The plume from the vent continued to deposit variable amounts of ash, spatter, and Pele's hair onto nearby areas. At Pu'u 'O'o Crater, glow emanated from three spatter cones and a small lava pond on the E part of the crater floor. The Kahauale’a II lava flows traveled N from the base of Pu'u 'O'o cone. The most distal front of the flow was 1.8 km from its source at a spatter cone on the NE edge of Pu'u 'O'o's crater floor. At 0740 on 26 May lava began to spill from the N side of the NE spatter cone, feeding a new breakout on the N flank of Pu'u 'O'o. Peace Day activity, fed by lava tubes extending from Pu'u 'O'o, consisted of some breakout activity on the pali and coastal plain, but mainly flows entering the ocean at locations inside and outside the National Park boundary. Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
Kizimen (Russia) | 22 May-28 May 2013 | Continuing ActivityCite this Report
Kizimen Eastern Kamchatka Volcanic Arc	KVERT reported that during 17-24 May moderate seismic activity continued at Kizimen. Video and satellite data showed that lava continued to extrude from the summit, producing incandescence, strong gas-and-steam activity, and hot avalanches on the W and E flanks. A thermal anomaly was detected daily in satellite images. The Aviation Color Code remained at Orange. Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Pacaya (Guatemala) | 22 May-28 May 2013 | Continuing ActivityCite this Report
Pacaya Central America Volcanic Arc	INSIVUMEH reported that during 22-23 May weak Strombolian activity at Pacaya's MacKenney cone was detected by the seismic network. On 24 May white plumes rose 600 m and drifted S. In a special bulletin on 25 May, INSIVUMEH noted that the eruptive pattern had changed during the previous few days. Explosions were more continuous and energetic, and were detected 3-5 minutes apart. Explosions ejected bombs and generated rumbles heard 4 km away. Cloud cover mostly prevented views on 27 May, but blue gas plumes were observed. Occasional weak glow from the crater was observed on 28 May. Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Paluweh (Indonesia) | 22 May-28 May 2013 | Continuing ActivityCite this Report
Paluweh Sunda Volcanic Arc	Based on analyses of satellite imagery and wind data, the Darwin VAAC reported that during 21-22 and 24 May ash plumes from Paluweh rose to altitudes of 2.1-3 km (7,000-10,000 ft) a.s.l. and drifted 25-55 km NW, W, and E. Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Sangay (Ecuador) | 22 May-28 May 2013 | Continuing ActivityCite this Report
Sangay Andean Northern Volcanic Arc	Based on a pilot report, the Washington VAAC reported that on 23 May an ash plume from Sangay drifted W at an altitude of 7.6 km (25,000 ft) a.s.l. Weather clouds prevented satellite image views of the plume. Source: Washington Volcanic Ash Advisory Center (VAAC)
Sheveluch (Russia) | 22 May-28 May 2013 | Continuing ActivityCite this Report
Sheveluch Eastern Kamchatka Volcanic Arc	Based on visual observations and analyses of satellite data, KVERT reported that during 17-24 May a viscous lava flow effused on the N flank of Shiveluch's lava dome, accompanied by hot avalanches, incandescence, and fumarolic activity. Satellite imagery showed a daily thermal anomaly on the lava dome. The Aviation Color Code remained at Orange. Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Tolbachik (Russia) | 22 May-28 May 2013 | Continuing ActivityCite this Report
Tolbachik Eastern Kamchatka Volcanic Arc	KVERT reported that the S fissure along the W side of Tolbachinsky Dol, a lava plateau on the SW side of Tolbachik, continued to produce very fluid lava flows during 17-24 May that traveled to the W, S, and E sides of the plateau. Cinder cones continued to grow along the S fissure and weak gas-and-steam plumes were observed. A large thermal anomaly on the N part of Tolbachinsky Dol was visible daily in satellite imagery. The Aviation Color Code remained at Orange. Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Yasur (Vanuatu) | 22 May-28 May 2013 | Continuing ActivityCite this Report
Yasur Vanuatu Volcanic Arc	On 28 May, the Vanuatu Geohazards Observatory reported that activity at Yasur continued to increase slightly, and bombs fell around the summit area, the tourist walk, and the parking area. Ash venting and dense white plumes from the crater were observed. Photos included in the report showed ash emissions and ashfall on 5 and 8 May, and dense white plumes on 23 and 24 May. The Alert Level remained at 2 (on a scale of 0-4). Source: Vanuatu Meteorology and Geohazards Department (VMGD)

Weekly Reports Archive

Since the Weekly Volcanic Activity Report began in November 2000, there have been 20,322 individual reports over 1,229 weeks (average of 17 per week) on 336 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.

Some of the documents on this server may contain live references (or pointers) to information created and maintained by other organizations. Please note that USGS does not control and cannot guarantee the relevance, timeliness, or accuracy of these outside materials.

For site security purposes and to ensure that this service remains available to all users, this government computer system employs software programs to monitor network traffic to identify unauthorized attempts to upload or change information, or otherwise cause damage. Unauthorized attempts to upload information or change information on this website are strictly prohibited and may be punishable under the Computer Fraud and Abuse Act of 1986 and the National Information Infrastructure Protection Act. Information may also be used for authorized law enforcement investigations. (Last modified September 21, 1999.)

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)