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Smithsonian / USGS Weekly Volcanic Activity Report

Weekly Volcanic Activity Map

The Weekly Volcanic Activity Report is a cooperative project between the Smithsonian's Global Volcanism Program and the US Geological Survey's Volcano Hazards Program. Updated by 2300 UTC every Wednesday and averaging 16 reported volcanoes, this is not a comprehensive list of all eruptions this week, but rather a summary of activity that meet criteria discussed in the "Criteria and Disclaimers" section below.

Volcanic activity reported here is preliminary and subject to change. Carefully reviewed, detailed narratives over longer time periods are published as reports of the Bulletin of the Global Volcanism Network available through volcano profile pages.

Smithsonian / USGS Weekly Volcanic Activity Report for the week of 11 May-17 May 2011
Name Country Volcanic Province Eruption Start Date Report Status
Asosan Japan Nankai Volcanic Arc New
Bulusan Philippines Eastern Philippine Volcanic Arc New
Etna Italy Sicily Volcanic Province New
Kizimen Russia Eastern Kamchatka Volcanic Arc New
Telica Nicaragua Central America Volcanic Arc New
Tungurahua Ecuador Andean Northern Volcanic Arc New
Ulawun Papua New Guinea Bismarck Volcanic Arc New
Yasur Vanuatu Vanuatu Volcanic Arc 1270 ± 110 years New
Aira Japan Ryukyu Volcanic Arc 2017 Mar 25 Continuing
Bagana Papua New Guinea Solomon Volcanic Arc 2000 Feb 28 (in or before) Continuing
Batu Tara Indonesia Sunda Volcanic Arc Continuing
Dukono Indonesia Halmahera Volcanic Arc 1933 Aug 13 Continuing
Karymsky Russia Eastern Kamchatka Volcanic Arc Continuing
Kilauea United States Hawaiian-Emperor Hotspot Volcano Group Continuing
Novarupta United States Alaska Peninsula Volcanic Arc Continuing
Popocatepetl Mexico Trans-Mexican Volcanic Belt 2005 Jan 9 Continuing
Santa Maria Guatemala Central America Volcanic Arc 1922 Jun 22 Continuing
Sheveluch Russia Eastern Kamchatka Volcanic Arc 1999 Aug 15 Continuing
Soufriere Hills United Kingdom Lesser Antilles Volcanic Arc Continuing
All times are local unless otherwise stated.
Weekly Reports Archive

Since the Weekly Volcanic Activity Report began in November 2000, there have been 20,274 individual reports over 1,227 weeks (average of 17 per week) on 334 different volcanoes.

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Agung Cotopaxi Iliamna Little Sitkin Poas Sulu Range
Ahyi Cuicocha Iliwerung Llaima Popocatepetl Sumbing
Aira Cumbal Inielika Lokon-Empung Purace Sundoro
Akan Dabbahu Ioto Lonquimay Puyehue-Cordon Caulle Suoh
Alaid Davidof Irazu Lopevi Rabaul Suretamatai
Alu-Dalafilla Dempo Iya Machin Raikoke Suwanosejima
Ambae Descabezado Grande Izu-Torishima Makushin Ranakah Taal
Ambang Dieng Volcanic Complex Jackson Segment Maly Semyachik Raoul Island Tair, Jebel at
Ambrym Dukono Kaba Manam Rasshua Takawangha
Anatahan East Epi Kadovar Manda Hararo Raung Talang
Aniakchak Ebeko Kaitoku Seamount Marapi Redoubt Tambora
Antillanca Volcanic Complex Ebulobo Kama'ehuakanaloa Maroa Reventador Tanaga
Antuco Edgecumbe Kambalny Martin Reykjanes Tandikat-Singgalang
Apoyeque Egon Kanaga Masaya Rincon de la Vieja Tangkoko-Duasudara
Arenal Ekarma Kanlaon Maule, Laguna del Rinjani Tangkuban Parahu
Asamayama Eldey Karangetang Mauna Loa Ritter Island Tara, Batu
Askja Erebus Karkar Mayon Rotorua Ta'u
Asosan Erta Ale Karthala McDonald Islands Ruang Taupo
Atka Volcanic Complex Etna Karymsky Melebingoy Ruapehu Telica
Augustine Etorofu-Yakeyama [Grozny Group] Kasatochi Melimoyu Ruby Tenerife
Avachinsky Eyjafjallajokull Katla Merapi Ruiz, Nevado del Tengger Caldera
Awu Fagradalsfjall Katmai Midagahara Sabancaya Three Sisters
Axial Seamount Fernandina Kavachi Misti, El Sakar Tinakula
Azul, Cerro Fogo Kelimutu Miyakejima Salak Tofua
Azumayama Fonualei Kelud Momotombo San Cristobal Tokachidake
Bagana Fournaise, Piton de la Kerinci Monowai San Miguel Tolbachik
Balbi Fourpeaked Ketoi Montagu Island San Vicente Toliman
Bamus Fuego Kharimkotan Moyorodake [Medvezhia] Sangay Tongariro
Banda Api Fujisan Kick 'em Jenny Mutnovsky Sangeang Api Trident
Bardarbunga Fukutoku-Oka-no-Ba Kie Besi Myojinsho Santa Ana Tungurahua
Barren Island Galeras Kikai Nabro Santa Maria Turrialba
Batur Galunggung Kilauea Negra, Sierra Sao Jorge Ubinas
Bezymianny Gamalama Kirishimayama Negro, Cerro Sarigan Ugashik-Peulik
Bogoslof Gamkonora Kita-Ioto Nightingale Island Sarychev Peak Ukinrek Maars
Brava Gareloi Kizimen Nishinoshima Saunders Ulawun
Bristol Island Gaua Klyuchevskoy Nisyros Savo Unnamed
Bulusan Gorely Kolokol Group Novarupta Semeru Unnamed
Calbuco Great Sitkin Koryaksky NW Rota-1 Semisopochnoi Veniaminof
Callaqui Grimsvotn Krakatau Nyamulagira Seulawah Agam Villarrica
Cameroon Guagua Pichincha Krummel-Garbuna-Welcker Nyiragongo Sheveluch Vulcano
Campi Flegrei Guallatiri Krysuvik-Trolladyngja Ofu-Olosega Shishaldin West Mata
Campi Flegrei del Mar di Sicilia Guntur Kuchinoerabujima Okataina Simbo Westdahl
Cayambe Hachijojima Kurikomayama Okmok Sinabung Whakaari/White Island
Chachadake [Tiatia] Hakoneyama Kusatsu-Shiranesan Ontakesan Sinarka Witori
Chaiten Heard Kverkfjoll Oraefajokull Siple Wolf
Chiginagak Hekla La Palma Osorno Sirung Wrangell
Chikurachki Helgrindur Lamington Pacaya Slamet Yakedake
Chiles-Cerro Negro Hierro Lamongan Pagan Snaefellsjokull Yasur
Chillan, Nevados de Hokkaido-Komagatake Langila Palena Volcanic Group Soputan Yufu-Tsurumi
Chirinkotan Home Reef Lanin Paluweh Sorikmarapi Zaozan [Zaosan]
Chirpoi Hood Lascar Panarea Sotara Zavodovski
Ciremai Huaynaputina Late Papandayan Soufriere Hills Zhupanovsky
Cleveland Hudson, Cerro Lateiki Pavlof Soufriere St. Vincent Zubair Group
Colima Huila, Nevado del Lengai, Ol Doinyo Pelee South Sarigan Seamount
Colo Hunga Tonga-Hunga Ha'apai Leroboleng Peuet Sague Spurr
Concepcion Ibu Lewotobi Pinatubo St. Helens
Copahue Ijen Lewotolok Planchon-Peteroa Stromboli
 News Feeds and Google Placemarks


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The RSS (Really Simple Syndication) feed is identical to the Weekly Volcanic Activity Report minus some features including the header information (latitude and longitude and summit elevation), the Geologic Summary, and a link to the volcano's page from the Global Volcanism Program. At the end of each report is a list of the sources used. Each volcano report includes a link from the volcano's name back to the more complete information in the Weekly Volcanic Activity Report on the Smithsonian website. This feature was first made available on 5 March 2008.



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A Google Earth network link for the Weekly Volcanic Activity Report can be loaded into the free Google Earth software, and in turn will load placemarks for volcanoes in the current weekly report. Placemark balloons include the volcano name, report date, report text, sources, and links back to the GVP volcano profile page and to the complete Weekly Report for that week. This feature was first made available on 1 April 2009.

 Criteria & Disclaimers

Criteria



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.

Disclaimers



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)

Report for Asosan
Based on pilot observations, the Tokyo VAAC reported that on 15 May an ash plume from Aso rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted NE. JMA reported that the next day plumes rose to altitudes of 1.8-2.1 km (6,000-7,000 ft) a.s.l. A pilot noted that an ash plume rose to an altitude of 2.4 km (8,000 ft) a.s.l. and drifted N that same day. During 17-18 May the JMA reported that ash plumes rose to an altitude of 1.8 km (6,000 ft) a.s.l. and drifted E and SE.
Source: Tokyo Volcanic Ash Advisory Center (VAAC)
Report for Bulusan
On 13 May, PHIVOLCS reported that an explosion from Bulusan's summit crater was accompanied by a rumbling sound audible up to 5 km away. The event was recorded by the seismic network as an explosion-type earthquake lasting for about 10 minutes. Cloud cover prevented observations of the summit area. Field investigation conducted immediately after the explosion confirmed the presence of thin ash deposits (0.5- 2.5 mm) approximately 9 km away from the crater in the NW and SW sectors. Several barangays in the municipalities of Juban and Irosin reported light ashfall. The Alert Level remained at 1 (on a scale of 0-5). Entry into the permanent danger zone, defined by a 4-km radius around the volcano, was prohibited.

During 15-16 May the seismic network detected four earthquakes. Then, on 16 May, the number of earthquakes rapidly increased to 80 in a seven-hour period. On 17 May PHIVOLCS reported that 144 earthquakes were recorded in the previous 24 hours. Steam rose from the active vents.
Source: Philippine Institute of Volcanology and Seismology (PHIVOLCS)
Report for Etna
Sezione di Catania - Osservatorio Etneo reported that on 8 May mild and discontinuous Strombolian activity resumed at the pit crater located on the E flank of Etna's SE Crater cone. On 11 May volcanic tremor amplitude progressively increased, and at about 2030 lava started to overflow the E crater rim. The activity intensified during the following hours and, shortly before 0400 on 12 May, culminated with lava fountaining which generated an ash cloud that drifted SSE. The lava fountaining lasted around 2 hours, showing a gradual diminution around 0545; an abrupt drop in the volcanic tremor amplitude at 0610 marked the end of the eruptive activity.
Source: Sezione di Catania - Osservatorio Etneo (INGV)
Report for Kizimen
KVERT reported that on 5 and 11 May seismicity from Kizimen was high; seismic data was not collected the other days during 6-13 May because of technical problems. Satellite images showed a large bright thermal anomaly daily on the volcano. During 6-7 May, ash plumes drifted 45 km SE and gas-and-steam plumes drifted 59 km N. Ashfall formed a layer as thick as 1 mm in Milkovo village, 120 km SW, on 10 May. A The Aviation Color Code remained at Orange.
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Report for Telica
Based on reports from INETER, the Washington VAAC stated that emissions of gas-and-ash from Telica were detected on 15 May, and ash fell in areas 4 km N. Seismicity was elevated for a period of time.
Source: Washington Volcanic Ash Advisory Center (VAAC)
Report for Tungurahua
IG reported that, although visual observations of Tungurahua during 11-15 May were often limited due to cloud cover, gas-and-steam plumes were noted during 12-14 May that rose 200-300 m above the crater and drifted E, SE, W, and NW. A small explosion on 15 May produced an ash plume that rose 500 m above the crater and drifted E. An ash plume the next day rose 200 m and drifted E. On 16 May an ash plume rose to an altitude of 8 km (26,200 ft) a.s.l. and drifted E, NE, and N. Incandescent blocks were ejected from the crater and rolled up to 500 m down the flanks. Ashfall was reported in the region of the Negro river.
Source: Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN)
Report for Ulawun
RVO reported that during 13-14 and 17 May gray-to-brown ash plumes rose above Ulawun. On 17 May the emissions were forceful for a short time and booming noises were reported. Light ashfall was reported in areas between Ubili in the NW and Voluvolu in the NE.
Source: Rabaul Volcano Observatory (RVO)
Report for Yasur
On 12 May, the Vanuatu Geohazards Observatory reported that, based on information collected by the Vanuatu Meteorology and Geohazards Department, satellite imagery showed strong degassing from Yasur during the previous week. Residents living close to the volcano reported persistent strong explosions that were heard and felt on 12 May. The Vanuatu Volcano Alert Level (VVAL) remained at 2 (on a scale of 0-4).
Source: Vanuatu Meteorology and Geohazards Department (VMGD)
Report for Aira
Based on information from JMA, the Tokyo VAAC reported that during 11-18 May explosions from Sakura-jima sometimes produced plumes that rose to altitudes of 1.8-2.4 km (6,000-8,000 ft) a.s.l. Plumes occasionally drifted SE and S. During 11, 13-14, and 17 May, pilots observed ash plumes that rose to altitudes of 2.1-3 km (7,000-10,000 ft) a.s.l.
Source: Tokyo Volcanic Ash Advisory Center (VAAC)
Report for Bagana
Based on analyses of satellite imagery, the Darwin VAAC reported that on 16 May an ash plume from Bagana rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted 55 km NE.
Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Report for Batu Tara
Based on analyses of satellite imagery, the Darwin VAAC reported that on 15 and 17 May ash plumes from Batu Tara rose to an altitude of 1.8 km (6,000 ft) a.s.l. and drifted 75-130 km W and NW.
Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Report for Dukono
Based on analyses of satellite imagery, the Darwin VAAC reported that during 11-12 May ash plumes from Dukono rose to an altitude of 4.3 km (14,000 ft) a.s.l. and drifted 75-110 km NE and E. On 16 May an ash plume rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted over 90 km E.
Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Report for Karymsky
KVERT reported moderate seismic activity at Karymsky during 6-13 May. Possible ash plumes rose to an altitude of 6 km (19,700 ft) a.s.l. on 10 May and to an altitude of 4.2 km (13,800 ft) a.s.l. on the other days. Pilots reported that on 6 May ash plumes rose to an altitude of 3 km (9,800 ft) a.s.l. Satellite imagery showed a thermal anomaly and ash plumes that drifted 340 km E during 6-7 May. The Aviation Color Code remained at Orange.
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Report for Kilauea
HVO reported that two lava lakes at Kilauea were active during 11-17 May. The level of the summit lava lake fluctuated but remained mostly stable deep in the vent inset within the E wall of Halema'uma'u Crater. Lava from a vent above the south side cascaded down into the lake. A gas plume from the vent generally drifted SW or W and deposited very small amounts of ash nearby. At Pu'u 'O'o crater, lava mostly from vents near the W edge of the lake continued to fill in a perched lava lake in the center of the crater floor. The lake level fluctuated and occasionally overflowed the edges, sending lava onto the Pu'u 'O'o crater floor.
Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
Report for Novarupta
Based on analysis of satellite imagery, pilot observations, KVERT reports, and information from AVO, the Anchorage VAAC reported that on 11 May strong winds in the Katmai area re-suspended loose ash deposited during the 1912 eruption. The Volcano Alert Level remained at Normal and the Aviation Color Code remained at Green.
Source: Anchorage Volcanic Ash Advisory Center (VAAC)
Report for Popocatepetl
CENAPRED reported steam-and-gas emissions from Popocatépetl during 11-17 May. The emissions occasionally contained small amounts of ash during 14-17 May.
Source: Centro Nacional de Prevencion de Desastres (CENAPRED)
Report for Santa Maria
INSIVUMEH reported that during 12-13 May explosions from Santa María's Santiaguito lava dome complex produced ash plumes that rose 900 m above Caliente dome and drifted SE, depositing fine ash in areas downwind. During 14-15 May explosions produced ash plumes that rose 2 km above Caliente dome. Pyroclastic flows descended the SW and E flanks. Rumbling noises and block avalanches were also noted. Ash was deposited on the E, S, SW, and W flanks including the communities of Loma Linda, San Marcos, and Palajunoj. During 16-17 May explosions produced ash plumes that rose 0.7-1 km above Caliente dome and drifted SW. A pyroclastic flow traveled E.
Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Report for Sheveluch
KVERT reported that during 5-7 May seismic data at Shiveluch indicated that possible ash plumes rose to an altitude of 3.9 km (12,800 ft) a.s.l. According to ground-based observations ash plumes rose to an altitude of 7.5 km (24,600 ft) a.s.l. on 7 May and to altitudes of 3-4 km (9,800-13,100 ft) a.s.l. during 5-6 and 8 May. Satellite imagery showed ash plumes drifting 196 km N during 5-6 May. On 7 May small ash clouds drifted S and SE, and gas-and-steam plumes drifted 230 km E. A thermal anomaly was detected during 7-8 May. KVERT noted that the Aviation Color Code remained at Orange. Based on information from KEMSD, the Tokyo VAAC reported that on 15 May an eruption produced a plume that rose to an altitude of 6.1 km (20,000 ft) a.s.l. and drifted E.
Sources: Kamchatkan Volcanic Eruption Response Team (KVERT), Tokyo Volcanic Ash Advisory Center (VAAC)
Report for Soufriere Hills
MVO reported that during 6-13 May activity at the Soufrière Hills lava dome was at a low level. On 11 May a pyroclastic flow that occurred in the February 2010 collapse scar traveled about 1 km. An ash cloud rose 1.8 km and drifted NNE, causing light ashfall in Lookout village. The Hazard Level remained at 3.
Source: Montserrat Volcano Observatory (MVO)