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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 5 January-11 January 2011
Name Country Volcanic Province Eruption Start Date Report Status
Etna Italy Sicily Volcanic Province 2022 Nov 27 New
Kizimen Russia Eastern Kamchatka Volcanic Arc New
Manam Papua New Guinea Bismarck Volcanic Arc 2018 May 10 ± 10 days New
Aira Japan Ryukyu Volcanic Arc 2017 Mar 25 Continuing
Bulusan Philippines Eastern Philippine Volcanic Arc Continuing
Dukono Indonesia Halmahera Volcanic Arc 1933 Aug 13 Continuing
Fuego Guatemala Central America Volcanic Arc 2002 Jan 4 Continuing
Karymsky Russia Eastern Kamchatka Volcanic Arc 2024 Jun 20 Continuing
Kilauea United States Hawaiian-Emperor Hotspot Volcano Group 2024 Sep 15 Continuing
Merapi Indonesia Sunda Volcanic Arc 2020 Dec 31 Continuing
Pacaya Guatemala Central America Volcanic Arc Continuing
Reventador Ecuador Northern Andean Volcanic Arc 2008 Jul 27 Continuing
San Cristobal Nicaragua Central America Volcanic Arc 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
Suwanosejima Japan Ryukyu Volcanic Arc 2004 Oct 23 Continuing
Tungurahua Ecuador Northern Andean 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 20,740 individual reports over 1,248 weeks (average of 17 per week) on 338 different volcanoes.

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Adams Cotopaxi Iliwerung Llaima Popocatepetl Sumisujima
Agung Cuicocha Inielika Lokon-Empung Purace Sundoro
Ahyi Cumbal Ioto Lonquimay Puyehue-Cordon Caulle Suoh
Aira Dabbahu Irazu Lopevi Rabaul Suretamatai
Akan Davidof Iwatesan Machin Raikoke Suwanosejima
Alaid Dempo Iya Makushin Ranakah Taal
Alu-Dalafilla Descabezado Grande Izu-Torishima Maly Semyachik Raoul Island Tair, Jebel at
Ambae Dieng Volcanic Complex Jackson Segment Manam Rasshua Takawangha
Ambang Dukono Kaba Manda Hararo Raung Talang
Ambrym East Epi Kadovar Marapi Redoubt Tambora
Anatahan Ebeko Kaitoku Seamount Maroa Reventador Tanaga
Aniakchak Ebulobo Kama'ehuakanaloa Martin Reykjanes Tandikat-Singgalang
Antillanca Volcanic Complex Edgecumbe Kambalny Masaya Rincon de la Vieja Tangkoko-Duasudara
Antuco Egon Kanaga Matthew Island Rinjani Tangkuban Parahu
Apoyeque Ekarma Kanlaon Maule, Laguna del Ritter Island Tara, Batu
Arenal Eldey Karangetang Mauna Loa Rotorua Ta'u
Asamayama Erebus Karkar Mayon Ruang Taupo
Askja Erta Ale Karthala McDonald Islands Ruapehu Telica
Asosan Etna Karymsky Melebingoy Ruby Tenerife
Atka Volcanic Complex Etorofu-Yakeyama [Grozny Group] Kasatochi Melimoyu Ruiz, Nevado del Tengger Caldera
Augustine Eyjafjallajokull Katla Merapi Sabancaya Three Sisters
Avachinsky Fagradalsfjall Katmai Midagahara Sakar Tinakula
Awu Fernandina Kavachi Misti, El Salak Tofua
Axial Seamount Fogo Kelimutu Miyakejima San Cristobal Tokachidake
Azul, Cerro Fonualei Kelud Momotombo San Miguel Tolbachik
Azumayama Fournaise, Piton de la Kerinci Monowai San Vicente Toliman
Bagana Fourpeaked Ketoi Montagu Island Sangay Tongariro
Balbi Fuego Kharimkotan Moyorodake [Medvezhia] Sangeang Api Trident
Bamus Fujisan Kick 'em Jenny Mutnovsky Santa Ana Tungurahua
Banda Api Fukutoku-Oka-no-Ba Kie Besi Myojinsho Santa Maria Turrialba
Bardarbunga Galeras Kikai Nabro Sao Jorge Ubinas
Barren Island Galunggung Kilauea Negra, Sierra Sarigan Ugashik-Peulik
Batur Gamalama Kirishimayama Negro, Cerro Sarychev Peak Ukinrek Maars
Bezymianny Gamkonora Kita-Ioto Nightingale Island Saunders Ulawun
Bogoslof Gareloi Kizimen Nishinoshima Savo Unnamed
Brava Gaua Klyuchevskoy Nisyros Semeru Unnamed
Bristol Island Gorely Kolokol Group Novarupta Semisopochnoi Veniaminof
Bulusan Great Sitkin Koryaksky NW Rota-1 Seulawah Agam Villarrica
Calbuco Grimsvotn Krakatau Nyamulagira Sheveluch Vulcano
Callaqui Guagua Pichincha Krummel-Garbuna-Welcker Nyiragongo Shishaldin West Mata
Cameroon Guallatiri Krysuvik-Trolladyngja Ofu-Olosega Simbo Westdahl
Campi Flegrei Guntur Kuchinoerabujima Okataina Sinabung Whakaari/White Island
Campi Flegrei del Mar di Sicilia Hachijojima Kurikomayama Okmok Sinarka Witori
Cayambe Hakoneyama Kusatsu-Shiranesan Ontakesan Siple Wolf
Chachadake [Tiatia] Heard Kverkfjoll Oraefajokull Sirung Wrangell
Chaiten Hekla La Palma Osorno Slamet Yakedake
Chiginagak Helgrindur Lamington Pacaya Snaefellsjokull Yasur
Chikurachki Hierro Lamongan Pagan Soputan Yellowstone
Chiles-Cerro Negro Hokkaido-Komagatake Langila Palena Volcanic Group Sorikmarapi Yufu-Tsurumi
Chillan, Nevados de Home Reef Lanin Paluweh Sotara Zaozan [Zaosan]
Chirinkotan Hood Lascar Panarea Soufriere Hills Zavodovski
Chirpoi Huaynaputina Late Papandayan Soufriere St. Vincent Zhupanovsky
Ciremai Hudson, Cerro Lateiki Pavlof South Sarigan Seamount Zubair Group
Cleveland Huila, Nevado del Lengai, Ol Doinyo Pelee Spurr
Colima Hunga Tonga-Hunga Ha'apai Leroboleng Peuet Sague St. Helens
Colo Ibu Lewotobi Pinatubo Stromboli
Concepcion Ijen Lewotolok Planchon-Peteroa Sulu Range
Copahue Iliamna Little Sitkin Poas Sumbing
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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 Etna
After a few hours of quiescence on the evening of 3 January, very weak emissions of incandescent material (probably mostly hot gas with little or no solid material) resumed from the pit crater located on the lower E flank of Etna's Southeast Crater cone. Later that evening intense incandescence from the pit crater was reported by observers in the village of S. Alfio on the E flank of Etna. The emissions continued on 4 January at a rate of 4-6 events per hour, producing small plumes that appeared as thermal anomalies in thermal video footage. Activity ceased in the afternoon. Very weak emissions of incandescent material (probably again mostly hot gas) were observed on 5 January at the same rate as the previous day. A camera recorded white vapor plumes occasionally accompanied by some grayish-brown ash. Weak, intermittent incandescence from the pit crater was observed at night during 5-6 January. Emissions on 6 January occurred at a frequency of 3-4 events per hour, producing small plumes seen in thermal camera footage. That same day, intense degassing occurred from the W vent of Bocca Nuova (BN-1), and from the Northeast Crater, where pulsating emissions produced mushroom-shaped vapor plumes.

Starting in the late evening of 11 January, the seismic network recorded a slight increase in volcanic tremor amplitude. The amplitude peaked early on 12 January, and the source of the tremor shifted from a location N of the Northeast Crater towards the Southeast Crater. Weak Strombolian activity from the pit crater accompanied these changes on 11 January, and gradually became more intense on 12 January.
Source: Sezione di Catania - Osservatorio Etneo (INGV)
Report for Kizimen
KVERT reported that ash emissions from Kizimen had been essentially continuous during 31 December-7 January, producing ash plumes mostly below altitudes of 6-8 km (20,000-26,000 ft) a.s.l. reported by pilots or observed in satellite imagery. Seismicity remained high but variable and volcanic tremor continued to be recorded. A thermal anomaly over the volcano was observed in satellite imagery. On 5 January ash plumes drifted more than 500 km ENE. Ashfall was reported on the Komandorsky Islands, 350-500 km E. The Tokyo VAAC reported that ash continued to be observed in satellite imagery on 5 Janaury. According to information from KVERT and analyses of satellite imagery, a possible eruption on 6 January produced a plume that rose to an altitude of 3.7 km (12,000 ft) a.s.l. and drifted E. Subsequent satellite images that same day showed continuing ash emissions. Ash plumes drifted NW on 9 January, and drifted NW again on 11 January, at an altitude of 2.7 km (9,000 ft) a.s.l. The Color Code remained at Red.
Sources: Tokyo Volcanic Ash Advisory Center (VAAC), Kamchatkan Volcanic Eruption Response Team (KVERT)
Report for Manam
RVO reported that during 5-6 January low roaring from Manam's South Crater was heard and weak but steady crater incandescence was observed at night. Diffuse blue vapor was emitted from South Crater on 6 January. During 6-8 January white vapor rose from Main Crater and incandescence from both craters was observed at night. Diffuse brown ash plumes occasionally rose from South Crater on 7 January. The next day the Alert Level was lowered from Stage 3 to Stage 2. During 8-9 January Main Crater emitted white vapor and South Crater produced occasional gray ash plumes that drifted to the SE part of the island. Emissions from Main Crater turned to gray on 10 January. White-to-blue vapor plumes rose from South Crater. Both craters were incandescent at night during 8-10 January.
Source: Rabaul Volcano Observatory (RVO)
Report for Aira
Based on information from JMA, the Tokyo VAAC reported that during 7-8 January explosions from Sakura-jima produced plumes that rose to altitudes of 1.8-2.1 km (6,000-7,000 ft) a.s.l. and drifted E and SE. On 8 January, pilots reported that ash plumes rose to altitudes of 1.8-3 km (6,000-10,000 ft) a.s.l. and drifted SE.
Source: Tokyo Volcanic Ash Advisory Center (VAAC)
Report for Bulusan
During 4-10 January, PHIVOLCS reported that 2-8 daily volcanic earthquakes at Bulusan were detected by the seismic network. Clouds usually prevented observations, but on 5 or 6 January steam was seen rising from a known NW thermal vent. The Tokyo VAAC reported that on 6 and 7 January ash was observed according to notices from the Manila airport (RPLL). The Alert Level remained at 1 (on a scale of 0-5).
Sources: Philippine Institute of Volcanology and Seismology (PHIVOLCS), Tokyo Volcanic Ash Advisory Center (VAAC)
Report for Dukono
Based on analyses of satellite imagery, the Darwin VAAC reported that during 5-7 January ash plumes from Dukono rose to altitudes of 2.4-3.7 km (8,000-12,000 ft) a.s.l. and drifted 65-130 km W.
Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Report for Fuego
INSIVUMEH reported that during 5-6 January explosions from Fuego produced ash plumes that rose 500-800 m above the crater and drifted 10 km S and SW. The explosions caused windows and roofs to rattle in areas 6 km away. Fine ashfall was reported in communities downwind including Panimaché (6 km SW), Morelia (7 km SW), and Yepocapa (8 km WNW). Incandescence from the crater was observed at night. On 8 January, the Washington VAAC reported multiple gas-and-ash plumes that rose to an altitude of 5.2 km (17,000 ft) a.s.l. were observed in satellite imagery. During 10-11 January INSIVUMEH again reported that explosions produced ash plumes that rose 500-800 m above the crater and shock waves that were detected as far away as 7 km. Plumes drifted 15 km W and block avalanches descended a few drainages.
Sources: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH), Washington Volcanic Ash Advisory Center (VAAC)
Report for Karymsky
KVERT reported that seismic activity at Karymsky was above background levels on 1 and 5 January, suggesting that possible ash plumes rose to an altitude of 3.8 km (12,500 ft) a.s.l. Seismic activity did not exceed background levels on the other days during 31 December-7 January. A thermal anomaly was detected daily in satellite imagery. An ash plume drifting 140 km SE was also seen in imagery on 2 January. Based on a pilot observation, the Tokyo VAAC reported that on 5 January an ash plume rose to an altitude of 4.6 km (15,000 ft) a.s.l.
Sources: Tokyo Volcanic Ash Advisory Center (VAAC), Kamchatkan Volcanic Eruption Response Team (KVERT)
Report for Kilauea
During 5-11 January, HVO reported that activity at Kilauea continued from the summit caldera and the east rift zone. At the summit caldera, the level of the lava-pool surface in the deep pit within Halema'uma'u crater circulated and remained mostly stable at approximately 120 m below the crater floor, periodically rising several meters higher. Nighttime incandescence was visible from the Jaggar Museum on the NW caldera rim. A plume from the vent that drifted SW, NE, and N deposited ash and fresh spatter nearby.

At the east rift zone, lava that broke out of the Quarry tube at a saddle between two rootless shields around 610 m elevation, continued to advance in two branches, E and W. At the lowest elevation of the E branch lava advanced along Highway 130 near Kalapana. One part of the W branch entered the ocean on 6 January at a location about 2 km SW of the end of Highway 130. Lava flows fed by an 8-m-high cone on the N portion of the Pu'u 'O'o crater floor covered and recovered the E crater floor. The web camera also recorded incandescence from a small fume-producing vent in the E wall of the crater. On 10 January the sides of the cone seemingly gave way and lava poured into two active flows that traveled toward the W portion of the crater floor.
Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
Report for Merapi
According to a news article, lahars on Merapi's flanks that occurred on 3 and 9 January caused damage to houses, farms, and infrastructure in multiple villages in the Magelang district, 26 km WNW of Merapi. One death and one injury were reported. On 9 January, the Red Cross evacuated people trapped in their homes in the Sirihan village. An estimated 3,000 people live in the flooded area, but the number of people evacuated was unknown.
Source: IRIN News
Report for Pacaya
INSIVUMEH reported that during 5-6 January steam-and-gas plumes, white and blue in color, rose 200 m above Pacaya's MacKenney cone. Seismic activity was consistent with gas emissions.
Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Report for Reventador
Based on a pilot observation, the Washington VAAC reported that on 4 January an ash plume from Reventador rose to an altitude of 5.2 km (17,000 ft) a.s.l. Cloud cover prevented clear satellite observations of the volcano. A subsequent report stated that IG noted low seismicity, no reports of ashfall, and that satellite imagery showed no ash emissions.
Source: Washington Volcanic Ash Advisory Center (VAAC)
Report for San Cristobal
Based on analyses of satellite imagery, the Washington VAAC reported that on 6 January a gas-and-steam plume from San Cristóbal, possibly containing ash, drifted 25 km SW. The VAAC noted a METAR weather notice stating that "smoke" was observed.
Source: Washington Volcanic Ash Advisory Center (VAAC)
Report for Santa Maria
INSIVUMEH reported that during 5-6 January explosions from Santa María's Santiaguito lava dome complex produced ash plumes that rose 400-500 m above Caliente dome and drifted SW. Based on analyses of satellite imagery, the Washington VAAC reported that on 8 January a gas plume possibly containing ash drifted less than 30 km SSW. During 10-11 January, INSIVUMEH reported that explosions produced ash plumes that rose as high as 600 m above the dome and drifted SW and W. Avalanches descended the S and E flanks.
Sources: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH), Washington Volcanic Ash Advisory Center (VAAC)
Report for Sheveluch
KVERT reported that moderate seismic activity from Shiveluch was detected during 31 December-7 January. A bright thermal anomaly over the volcano was observed daily in satellite imagery. Seismic data showed that possible ash plumes rose to an altitude of 5 km (16,400 ft) a.s.l. on 2 January. That same day an explosion generated ash plumes that rose to an altitude of 8 km (26,000 ft) a.s.l. and were observed in satellite imagery drifting 92 km S. Moderate gas-and-steam activity was visually observed during 2 and 5-6 January. The Aviation Color Code level remained at Orange.
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Report for Soufriere Hills
MVO reported that during 31 December 2010-7 January 2011 activity from the Soufrière Hills lava dome was at a low level. A small lahar descended the Belham valley (NW) on 5 January. Gas measurements on 6 January indicated that the ratio of hydrochloric acid to sulfur dioxide was 0.29, a ratio similar to those measured over the last few months and consistent with no lava extrusion. Helicopter observations that same day showed marked acid rain damage in the Spring (W) and Gingoes (SW) ghaut areas, up to 3 km from the lava dome. Cloudy weather prevented observations of the lava dome. The Hazard Level remained at 3.
Source: Montserrat Volcano Observatory (MVO)
Report for Suwanosejima
Based on information from JMA, the Tokyo VAAC reported an explosion from Suwanose-jima during 11-12 January. Details of a possible resulting plume were not reported.
Source: Tokyo Volcanic Ash Advisory Center (VAAC)
Report for Tungurahua
On 5 January IG reported that, after moderately-sized explosions during 24-25 December, activity at Tungurahua had decreased. IG noted that during this time seismicity decreased and explosions had not occurred, deflation was detected, sulfur dioxide emissions gradually reduced, and decreases in the amount of ash present in plumes was noted. Although cloudy weather often prevented observations during 5-11 January, steam plumes were occasionally observed and rose above the crater to low heights.
Source: Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN)