All times are local unless otherwise stated.

Ambae | 6 July-12 July 2011 | New Activity / Unrest Cite this Report
Ambae Vanuatu	On 11 July the Vanuatu Geohazards Observatory noted that there had been recent increases in activity from Aoba and that local earthquakes were volcanic. Satellite images collected by the Ozone Monitoring Instrument showed sulfur dioxide emissions. Observations on 4 June revealed that small explosions had been occurring from the crater lake and were accompanied by local ashfall around the crater. Some villagers in the N and W parts of the island had observed the explosions. The Vanuatu Volcano Alert Level (VVAL) remained at 1 (on a scale of 0-4). Source: Vanuatu Meteorology and Geohazards Department (VMGD)
Etna | 6 July-12 July 2011 | New Activity / Unrest Cite this Report
Etna Sicily (Italy)	Sezione di Catania - Osservatorio Etneo reported that explosions from the pit crater located on the E flank of Etna's SE Crater cone were heard on the morning of 4 July. Incandescence was observed later that evening. Small Strombolian eruptions were recorded by a camera during 5-6 July. On 7 July Strombolian activity gradually increased along with volcanic tremor amplitude. Small pyroclastic cones began to grow on the crater floor. During the next morning, volcanic tremor amplitude clearly increased. Shortly thereafter it abruptly decreased and the Strombolian activity completely ceased. During the morning of 9 July, Strombolian activity resumed and volcanic tremor amplitude rose rapidly. Around noon lava overflowed the E rim of the crater and followed the path of lava flows from the previous eruption, into the upper W part of the Valle del Bove. Later that day Strombolian explosions turned into a continuous lava fountain. A dense eruptive plume rose several kilometers high and drifted S and SE, causing ash and lapilli fall in populated areas including Trecastagni, Viagrande, and Acireale towards the SE, and between Nicolosi and Catania towards the S, forcing the closure of the Fontanarossa international airport in Catania. A few hours later volcanic tremor amplitude dropped to very low levels and all eruptive activity ceased. Source: Sezione di Catania - Osservatorio Etneo (INGV)
Ijen | 6 July-12 July 2011 | New Activity / Unrest Cite this Report
Ijen Eastern Java	The Darwin VAAC reported that on 10 July a pilot observed an ash plume drifting W from Ijen at an altitude of 3.7 km (12,000 ft) a.s.l. [Correction: Later reports from observers indicated that the plume was likely from a nearby forest fire and not from Ijen. Scientists noted that the seismic activity was quiet and that there were no increases in degassing or boiling of the lake.] Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Katla | 6 July-12 July 2011 | New Activity / Unrest Cite this Report
Katla Iceland	The Iceland Met Office and news sources reported that on 9 July a jökulhlaup from Myrdalsjökull, the ice sheet that covers Katla, originated from three ice cauldrons in the SE part of the caldera. During previous weeks microseismicity had been registered near several of the ice cauldrons. Around the time of peak harmonic tremor, in the early evening on 8 July, the Myrdalsjökull flood monitoring system indicated increased conduction. The water level reached the bridge around midnight and damaged the sensors. According to news articles, one new cauldron that had formed, along with cracks in the glacier around the cauldrons, may have been caused by a small eruption at Katla although no evidence of an eruption was observed. The jökulhlaup had destroyed a 128-m-long bridge and caused damage, resulting in the closing of part of the Ring Road. About 200 people were evacuated from the area but allowed to return home later that day. On 10 July the water had subsided and returned to normal levels. Sources: Morgunbladid News, Iceland Review, Iceland Review, Iceland Review, Icelandic Meteorological Office (IMO)
Lokon-Empung | 6 July-12 July 2011 | New Activity / Unrest Cite this Report
Lokon-Empung Sulawesi	CVGHM reported that during 28 June-9 July white plumes rose 50-400 m above Tompaluan crater, in the saddle between the Lokon-Empung peaks, and gray ash plumes rose 100-500 m above the crater. An ash eruption on 10 July produced white-to-gray plumes that rose 200-400 m above the crater. Fluctuations in the sulfur dioxide gas emission rate were noted during 30 June-10 July. Based on gas flux, seismicity, visual observations, and hazard assessment CVGHM raised the Alert Level to 4 (on a scale of 1-4). On 11 July, the Darwin VAAC reported that ash plumes detected in satellite imagery rose to an altitude of 1.5 km (5,000 ft) a.s.l. and drifted NW. According to news articles, close to 1,000 residents were evacuated from the area during 11-12 July. Sources: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM), Associated Press, Darwin Volcanic Ash Advisory Centre (VAAC)
Puyehue-Cordon Caulle | 6 July-12 July 2011 | New Activity / Unrest Cite this Report
Puyehue-Cordon Caulle Central Chile	OVDAS-SERNAGEOMIN reported that during 6-8 July cameras installed around the Puyehue-Cordón Caulle volcanic complex recorded eruption plumes that rose no higher than 2 km above the Cordón Caulle rift zone and drifted N and NE. On 6 July satellite imagery indicated that the plume drifted 75 km NE. During 7-8 July explosions recorded by the seismic network corresponded to increases in the plume height and, on 7 July, caused windows in Riñinahue to vibrate. According to news articles, numerous flights in and around Argentina and Uruguay were cancelled on 8 July and some airports had remained closed. On 9 July seismicity indicated that lava flows had ceased. During 9-11 July weather conditions prevented views of the eruption plume by cameras installed around the volcano. Based on analysis of satellite imagery, the Buenos Aires VAAC stated on 9 July that, although ash plumes rose to an altitude of 3 km (10,000 ft), activity was weakening. Ash was again detected by satellite during periods of clear weather the next day. The Alert Level remained at Red. Sources: Buenos Aires Volcanic Ash Advisory Center (VAAC), Agence France-Presse (AFP), Servicio Nacional de Geología y Minería (SERNAGEOMIN)
Stromboli | 6 July-12 July 2011 | New Activity / Unrest Cite this Report
Stromboli Aeolian Islands (Italy)	Sezione di Catania - Osservatorio Etneo reported that on 5 July a high pyroclastic jet formed in the S part of Stromboli's crater terrace producing tephra that fell back onto the Pizzo sopra la Fossa. Seismic data indicated that other craters on the terrace were also active. A similar but less powerful explosion occurred from the same vent on 10 July. Source: Sezione di Catania - Osservatorio Etneo (INGV)

Aira | 6 July-12 July 2011 | Continuing ActivityCite this Report
Aira Kyushu (Japan)	According to pilot observations, the Tokyo VAAC reported that on 7 and 10 July ash plumes rose from Sakura-jima to altitudes of 1.2-2.4 km (4,000-8,000 ft) a.s.l. Reports from JMA stated that plumes rose to altitudes of 1.8-2.4 km (6,000-8,000 ft) a.s.l. on 8, 10, and 12 July. Source: Tokyo Volcanic Ash Advisory Center (VAAC)
Batu Tara | 6 July-12 July 2011 | Continuing ActivityCite this Report
Batu Tara Komba Island	Based on analyses of satellite imagery, the Darwin VAAC reported that during 9-11 July ash plumes from Batu Tara rose to altitudes of 1.5-3 km (5,000-10,000 ft) a.s.l. and drifted 75 km W and NW. Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Dukono | 6 July-12 July 2011 | Continuing ActivityCite this Report
Dukono Halmahera	Based on analyses of satellite imagery, the Darwin VAAC reported that during 6-7 July ash plumes from Dukono rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted 55 km NW. Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Karymsky | 6 July-12 July 2011 | Continuing ActivityCite this Report
Karymsky Eastern Kamchatka (Russia)	KVERT reported that during 1-8 July moderate seismic activity continued at Karymsky and possible ash plumes rose to an altitude of 4 km (13,100 ft) a.s.l. Satellite imagery showed a thermal anomaly on the volcano during 2 and 4-5 June, and ash plumes that drifted 14 km NW and 38 km N on 2 and 5 July, respectively. The Aviation Color Code remained at Orange. Based on information from Yelizovo Airport (UHPP), the Tokyo VAAC reported that on 12 July an ash plume rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted SW. Sources: Tokyo Volcanic Ash Advisory Center (VAAC), Kamchatkan Volcanic Eruption Response Team (KVERT)
Kilauea | 6 July-12 July 2011 | Continuing ActivityCite this Report
Kilauea Hawaiian Islands (USA)	HVO reported that two lava lakes at Kilauea were active during 6-12 July. The level of the summit lava lake fluctuated deep in the vent inset within the E wall of Halema'uma'u Crater and circulated with various patterns. Spattering occurred at locations along the W edge of the lake. Periodic measurements indicated that the gas plume from the vent continued to deposit variable amounts of ash nearby. At Pu'u 'O'o, lava from vents near the NE edge and, to a lesser degree, along the W edge of the perched lava lake in the center of the crater floor continued to fill the lake. The lake level fluctuated and flowed through rim breaches, sending lava onto the Pu'u 'O'o crater floor. The near-vertical rim of the perched pond, which was elevated about 5 m higher than the surrounding sub-horizontal crater floor on the E side, continued to be uplifted; the crater floor and perched lake rims formed a nearly-continuous ramp sloping away from the lake. Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
Kizimen | 6 July-12 July 2011 | Continuing ActivityCite this Report
Kizimen Eastern Kamchatka (Russia)	KVERT reported that during 1-8 July observers on Tolbachik's flanks noted strong fumarolic activity from Kizimen. Deformation was also noted on those days. During 1-8 July seismicity was above background levels and volcanic tremor continued to be detected. A bright thermal anomaly was detected in satellite imagery during 2-5 July; cloud cover prevented observations of the volcano on the other days. The Aviation Color Code remained at Orange. Based on information from Yelizovo Airport (UHPP), the Tokyo VAAC reported that on 12 July an ash plume rose to an altitude of 6.4 km (21,000 ft) a.s.l. and drifted E. Sources: Tokyo Volcanic Ash Advisory Center (VAAC), Kamchatkan Volcanic Eruption Response Team (KVERT)
Pagan | 6 July-12 July 2011 | Continuing ActivityCite this Report
Pagan Mariana Islands (USA)	A Northern Mariana Islands status report noted that on 7 July a low-level gas-and-steam plume with possible fine ash was detected in satellite imagery as well as noted by observers on the island. Low-level gas-and-steam plumes had been detected in satellite imagery during the previous few weeks. The Aviation Color Code remained at Yellow and the Volcano Alert Level remained at Advisory. Source: Emergency Management Office of the Commonwealth of the Mariana Islands and United States Geological Survey Volcano Hazards Program
Sheveluch | 6 July-12 July 2011 | Continuing ActivityCite this Report
Sheveluch Central Kamchatka (Russia)	KVERT reported moderate seismic activity at Shiveluch during 1-8 July. Seismic data indicated that possible ash plumes rose to an altitude of 4.5 km (14,800 ft) a.s.l. on 4 and 6 July. Satellite imagery showed a thermal anomaly on the lava dome during 2-5 July and gas-and-ash plumes that drifted 78 km NE during 4-5 July. The Aviation Color Code remained at Orange. Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Slamet | 6 July-12 July 2011 | Continuing ActivityCite this Report
Slamet Central Java	CVGHM reported that between 6 September 2009 and July 2011 eruptions from Slamet had been absent and plumes (likely steam) rose as high as 500 m above the crater. Seismicity and the temperature of hot water from springs both decreased. On 11 July, the Alert Level was lowered to 1 (on a scale of 1-4). Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)

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)