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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 21 October-27 October 2009
Name Location Eruption Start Date Report Status
Chaiten Chile New
Ebeko Paramushir Island (Russia) 2016 Oct 20 New
Klyuchevskoy Central Kamchatka (Russia) New
Mayon Luzon (Philippines) New
Nevado del Huila Colombia New
Reventador Ecuador 2008 Jul 27 New
Soufriere Hills Montserrat New
Aira Kyushu (Japan) 2017 Mar 25 Continuing
Batu Tara Komba Island (Indonesia) Continuing
Colima Mexico Continuing
Dukono Halmahera (Indonesia) 1933 Aug 13 Continuing
Fuego Guatemala 2002 Jan 4 Continuing
Karymsky Eastern Kamchatka (Russia) 2021 Apr 3 Continuing
Kilauea Hawaiian Islands (USA) Continuing
Pacaya Guatemala 2015 Jun 7 ± 1 days Continuing
Rabaul New Britain (Papua New Guinea) Continuing
Santa Maria Guatemala 1922 Jun 22 Continuing
Sheveluch Central Kamchatka (Russia) 1999 Aug 15 Continuing
Weekly Reports Archive

Since the Weekly Volcanic Activity Report began in November 2000, there have been 16,863 individual reports over 1,073 weeks (average of 16 per week) on 311 different volcanoes.

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Agung Copahue Ijen Little Sitkin Pelee South Sarigan Seamount
Ahyi Cotopaxi Iliamna Llaima Peuet Sague Spurr
Aira Cuicocha Iliwerung Loihi Pinatubo St. Helens
Akan Cumbal Inielika Lokon-Empung Planchon-Peteroa Stromboli
Alaid Dabbahu Ioto Lopevi Poas Sulu Range
Alu-Dalafilla Dempo Irazu Machin Popocatepetl Sumbing
Ambae Descabezado Grande Iya Makian Puyehue-Cordon Caulle Sundoro
Ambang Dieng Volcanic Complex Izu-Torishima Makushin Rabaul Suretamatai
Ambrym Dukono Jackson Segment Maly Semyachik Raikoke Suwanosejima
Anatahan Ebeko Kaba Manam Ranakah Taal
Antillanca Volcanic Complex Ebulobo Kadovar Manda Hararo Raoul Island Tair, Jebel at
Antuco Egon Kambalny Marapi Rasshua Takawangha
Apoyeque Ekarma Kanaga Maroa Raung Talang
Arenal Epi Kanlaon Martin Redoubt Tambora
Asamayama Erebus Karangetang Masaya Reventador Tanaga
Askja Erta Ale Karkar Maule, Laguna del Reykjanes Tandikat-Singgalang
Asosan Etna Karthala Mauna Loa Rincon de la Vieja Tangkoko-Duasudara
Augustine Etorofu-Yakeyama [Grozny Group] Karymsky Mayon Rinjani Tangkuban Parahu
Avachinsky Eyjafjallajokull Kasatochi McDonald Islands Ritter Island Tara, Batu
Awu Fernandina Katla Melimoyu Rotorua Telica
Axial Seamount Fogo Katmai Merapi Ruang Tenerife
Azul, Cerro Fonualei Kavachi Midagahara Ruapehu Tengger Caldera
Azumayama Fournaise, Piton de la Kelimutu Misti, El Ruiz, Nevado del Three Sisters
Bagana Fourpeaked Kelut Miyakejima Sabancaya Tinakula
Balbi Fuego Kerinci Momotombo Sakar Tofua
Bamus Fujisan Ketoi Monowai Salak Tokachidake
Banda Api Fukutoku-Oka-no-Ba Kharimkotan Montagu Island San Cristobal Tolbachik
Bardarbunga Galeras Kick 'em Jenny Moyorodake [Medvezhia] San Miguel Toliman
Barren Island Galunggung Kikai Mutnovsky San Vicente Tongariro
Batur Gamalama Kilauea Myojinsho Sangay Tungurahua
Bezymianny Gamkonora Kirishimayama Nabro Sangeang Api Turrialba
Bogoslof Gareloi Kizimen Negra, Sierra Santa Ana Ubinas
Brava Gaua Klyuchevskoy Negro, Cerro Santa Maria Ugashik-Peulik
Bristol Island Gorely Kolokol Group Nightingale Island Sarigan Ukinrek Maars
Bulusan Great Sitkin Korovin Nishinoshima Sarychev Peak Ulawun
Calbuco Grimsvotn Koryaksky Nisyros Saunders Unnamed
Callaqui Guagua Pichincha Krakatau Novarupta Semeru Unnamed
Cameroon Guallatiri Krummel-Garbuna-Welcker NW Rota-1 Semisopochnoi Veniaminof
Campi Flegrei del Mar di Sicilia Guntur Krysuvik-Trolladyngja Nyamulagira Seulawah Agam Villarrica
Cayambe Hachijojima Kuchinoerabujima Nyiragongo Sheveluch West Mata
Cereme Hakoneyama Kurikomayama Okataina Shishaldin Westdahl
Chachadake [Tiatia] Heard Kusatsu-Shiranesan Okmok Simbo Whakaari/White Island
Chaiten Hekla Kverkfjoll Ontakesan Sinabung Witori
Chiginagak Helgrindur Lamington Oraefajokull Sinarka Wolf
Chikurachki Hierro Lamongan Osorno Siple Yasur
Chiles-Cerro Negro Hokkaido-Komagatake Langila Pacaya Sirung Zaozan [Zaosan]
Chillan, Nevados de Home Reef Lanin Pagan Slamet Zavodovski
Chirinkotan Hood Lascar Palena Volcanic Group Snaefellsjokull Zhupanovsky
Chirpoi Huaynaputina Lateiki Paluweh Soputan Zubair Group
Cleveland Hudson, Cerro Lengai, Ol Doinyo Panarea Sorikmarapi
Colima Huila, Nevado del Leroboleng Papandayan Sotara
Colo Hunga Tonga-Hunga Ha'apai Lewotobi Parker Soufriere Hills
Concepcion Ibu Lewotolok Pavlof Soufriere St. Vincent
 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 monthly, and 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 Chaiten
SERNAGEOMIN reported that Chaitén's lava-dome complex continued to grow during 1-15 October. Steam from the E part of the complex and ash-and-steam plumes from the center were seen on clear days using the web camera, S of the volcano. Small emissions originated from numerous areas. An explosion on 14 October produced a dense ash cloud that drifted W. The Alert Level remained at Red. Based on web camera views, the Buenos Aires VAAC reported continuous emissions on 21 October. Plumes rose to altitudes of 1.8-2.4 km (6,000-8,000 ft) a.s.l. and drifted SSE.
Sources: Servicio Nacional de Geología y Minería (SERNAGEOMIN), Buenos Aires Volcanic Ash Advisory Center (VAAC)
Report for Ebeko
Based on analyses of satellite imagery, the Tokyo VAAC reported that on 26 October a possible eruption plume from Ebeko rose to an altitude of 8.8 km (29,000 ft) a.s.l. and drifted E. Emissions continued the next day.
Source: Tokyo Volcanic Ash Advisory Center (VAAC)
Report for Klyuchevskoy
KVERT reported that during 16-23 October seismic activity from Kliuchevskoi was above background levels. Satellite imagery revealed a daily thermal anomaly at the volcano. During 16 and 18-22 October, Strombolian activity ejected tephra 500 m above the crater and fumarolic plumes were noted. The Level of Aviation Color Code remained at Orange.
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Report for Mayon
PHIVOLCS reported that on 28 October a minor ash explosion from Mayon produced a brownish ash plume that rose 600 m above the crater and drifted NE. The Alert Level remained at 2 (on a scale of 0-5). The 7-km Extended Danger Zone (EDZ) on the SE flank and the 6-km Permanent Danger Zone (PDZ) in all other areas remained in effect.
Source: Philippine Institute of Volcanology and Seismology (PHIVOLCS)
Report for Nevado del Huila
The Washington VAAC reported a possible eruption from Nevado del Huila on 20 October. An ash plume was seen on satellite imagery drifting 45 km S and INGEOMINAS had reported increased seismicity. Another ash cloud was seen on satellite imagery drifting S later that day.

Based on web camera views, INGEOMINAS reported that on 21 October continuous gas emissions rose from Nevado del Huila and pulses of ash emissions produced plumes that drifted E. Observations during an overflight on 23 October revealed that gas-and-ash emissions originated from two locations. The area of greater discharge was between Pico Central and the lava dome, while fewer emissions came from the fissure that opened in April 2007, NE of Pico Central. Lava-dome growth was concentrated on the N end of the lava dome, an area also exhibiting a thermal anomaly detected with a thermal imaging camera. The Alert Level remained at II (Orange; "probable eruption in term of days or weeks"). Ashfall and sulfur odors were reported in several inhabited areas on 23 and 24 October.

Based on analyses of satellite imagery and information from INGEOMINAS, the Washington VAAC reported that on 24 October an eruption produced an ash plume that rose to an altitude of 9.1 km (30,000 ft) a.s.l. and drifted WSW. During 25-26 October, thermal anomalies were seen on satellite imagery. A plume drifted WSW on 25 October and a gas-and-ash plume drifted 90 km NW and SW on 26 October.
Sources: Servicio Geológico Colombiano (SGC), Washington Volcanic Ash Advisory Center (VAAC)
Report for Reventador
The IG reported that on 21 October, steam-and-gas plumes from Reventador with little to no ash content rose 2-4 km above the crater and drifted NW, W, and S. An explosion that day ejected incandescent material from the crater; blocks rolled down the flanks. On 22 October, a few explosions generated ash-and-steam plumes with little to no ash content that rose 4 km and drifted NW, E, and SE. Observations during an overflight revealed a small lava flow on the N flank and a larger flow with four branches on the S flank. Some of the base of the lava dome had been removed, and small spines were present, especially on the S side of the dome. Thermal images revealed that material in the crater was 400 degrees Celsius and the lava-flow fronts were 250 degrees Celsius. Cloudy weather prevented visual observations during 23-26 October. Roaring noises were heard on 25 October.
Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)
Report for Soufriere Hills
MVO reported that during 16-25 October activity from the Soufrière Hills lava dome was at a high level; a new lava dome first reported on 9 October continued to grow in the summit region on the W side. The new dome was considerably higher than the older lava dome that is to the E. Seismicity was high and cycles of low-level tremor occurred at regular intervals. Several pyroclastic flows descended the White River to the S and reached the sea. Small pyroclastic flows traveled NE down Tuitts Ghaut and W down Gages valley, but seldom to the N down Tyers Ghaut or E down the Tar River valley. Rockfalls occurred on the S and SE flanks of the lava dome. Multiple ashfalls were reported in inhabited areas, and lahars traveled NW down the Belham valley. During 23-25 October, seismicity decreased and ash plumes generated by pyroclastic flows drifted W. The Hazard Level remained at 3.
Source: Montserrat Volcano Observatory (MVO)
Report for Aira
Based on information from JMA, the Tokyo VAAC reported that explosions from Sakura-jima during 21-22, 24-25, and 27-28 October produced plumes that rose to altitudes of 1.5-2.4 km (5,000-8,000 ft) a.s.l. Some plumes drifted W, SW, S, and SE.
Source: Tokyo Volcanic Ash Advisory Center (VAAC)
Report for Batu Tara
Based on analyses of satellite imagery, the Darwin VAAC reported that on 27 October ash plumes from Batu Tara were seen drifting 65 km W and NW at an altitude of 2.1 km (7,000 ft) a.s.l.
Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Report for Colima
The government of the state of Colima reported that on 22 October a gray plume from Colima rose to an altitude of 4 km (13,100 ft) a.s.l. and drifted SW. The next day, white plumes drifted NE and N, one at an altitude of 4.2 km (13,800 ft) a.s.l.
Source: Gobierno del Estado de Colima
Report for Dukono
Based on analyses of satellite imagery, the Darwin VAAC reported that during 22-23 and 26-27 October ash plumes from Dukono rose to altitudes of 2.1-2.4 km (7,000-8,000 ft) a.s.l. and drifted 45-95 km NE and E.
Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Report for Fuego
Based on analyses of satellite imagery and a pilot observation, the Washington VAAC reported that on 20 October an apparent ash plume from Fuego drifted SSW. On 21 October, multiple ash emissions resulted in an ash cloud that drifted 55 km S. Emissions were also reported the next day. On 26 October, a diffuse gas-and-ash plume drifted W. That same day, INSIVUMEH reported that explosions produced plumes that rose to altitudes of 4.4-4.8 km (14,400-15,700 ft) a.s.l. and drifted 10 km S and SW. Ash fell downwind, rumbling and degassing sounds were reported, and avalanches of blocks descended the flanks. On 27 October, a few ash clouds seen on satellite imagery drifted 90 km NW.
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 during 16-23 October and possibly indicated that ash plumes rose to an altitude of 3.9 km (12,800 ft) a.s.l. The Level of Aviation Color Code remained at Orange. Based on information from KEMSD, the Tokyo VAAC reported that eruptions during 24-25 October produced plumes that rose to altitudes of 3.4-3.7 km (11,000-12,000 ft) a.s.l. Ash was not identified on satellite imagery.
Sources: Kamchatkan Volcanic Eruption Response Team (KVERT), Tokyo Volcanic Ash Advisory Center (VAAC)
Report for Kilauea
During 21-27 October, HVO reported that lava flowed SE from underneath Kilauea's Thanksgiving Eve Breakout (TEB) and rootless shield complex through a lava tube system, reaching the Waikupanaha ocean entry on most days. Thermal anomalies detected in satellite images and visual observations revealed active surface lava flows. For a few days an active lava flow advanced on the coastal plain, burning vegetation and pavement along the former Kalapana access road. Intermittent incandescence was seen from the Pu'u 'O'o crater floor and an East wall vent.

The vent in Halema'uma'u crater continued to produce a diffuse white plume that drifted SW. Incandescence originated from occasionally spattering holes from a surface inside the vent cavity. Preliminary measurements indicated that the sulfur dioxide emission rate at the summit remained elevated; 560-1,400 tonnes per day was measured during 21-22 and 26 October. The 2003-2007 average rate was 140 tonnes per day.
Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
Report for Pacaya
On 23 and 26 October, INSIVUMEH reported that white and blue plumes from Pacaya's MacKenney cone rose 50-150 m and drifted W and SW. Multiple lava flows on the S flank traveled 75-350 m SSW.
Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Report for Rabaul
RVO reported that during 16-22 October diffuse white plumes and gray ash plumes rose from Rabaul caldera's Tavurvur cone; ash plumes rose 700 m above the crater. Ashfall was reported in areas to the NW.
Source: Rabaul Volcano Observatory (RVO)
Report for Santa Maria
Based on analyses of satellite imagery, the Washington VAAC reported that on 22 October multiple ash plumes from Santa María's Santiaguito lava dome complex drifted less than 20 km SW. On 23 and 26 October, INSIVUMEH reported that explosions produced ash plumes that rose above Caliente dome to altitudes of 3-3.3 km (10,000-10,800 ft) a.s.l. The plumes drifted W and SE and caused ashfall in areas downwind. Avalanches descended the SW flank of the dome. Degassing sounds resembling airplane engines were heard.
Sources: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH), Washington Volcanic Ash Advisory Center (VAAC)
Report for Sheveluch
KVERT reported that during 16-23 October seismic activity from Shiveluch was above background levels and possibly indicated that ash plumes rose to an altitude of 4.5 km (14,800 ft) a.s.l. Analyses of satellite imagery revealed a large thermal anomaly over the lava dome. According to video camera data and visual observations, multiple hot avalanches traveled down the lava dome. Deposits on the SE flank from a small pyroclastic flow were noted. Fumarolic plumes rose to altitudes of 2.8-5 km (9,200-16,400 ft) a.s.l. during 16, 18-20, and 22 October. The Level of Aviation Color Code remained at Orange.
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)