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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 15 August-21 August 2007
Name Country Volcanic Province Eruption Start Date Report Status
Chikurachki Russia Kuril Volcanic Arc New
Karangetang Indonesia Sangihe Volcanic Arc New
Kilauea United States Hawaiian-Emperor Hotspot Volcano Group New
Manda Hararo Ethiopia Afar Rift Volcanic Province New
Pavlof United States Aleutian Ridge Volcanic Arc New
Cleveland United States Aleutian Ridge Volcanic Arc Continuing
Fuego Guatemala Central America Volcanic Arc 2002 Jan 4 Continuing
Karymsky Russia Eastern Kamchatka Volcanic Arc 2024 Jun 20 Continuing
Klyuchevskoy Russia Eastern Kamchatka Volcanic Arc Continuing
Manam Papua New Guinea Bismarck Volcanic Arc 2018 May 10 ± 10 days Continuing
Rabaul Papua New Guinea Bismarck Volcanic Arc Continuing
Sangay Ecuador Northern Andean Volcanic Arc 2019 Mar 26 Continuing
Sheveluch Russia Eastern Kamchatka Volcanic Arc 1999 Aug 15 Continuing
Soufriere Hills United Kingdom Lesser Antilles Volcanic Arc Continuing
St. Helens United States High Cascades Volcanic Arc 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 20,531 individual reports over 1,239 weeks (average of 17 per week) on 336 different volcanoes.

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Agung Cotopaxi Iliamna Little Sitkin Planchon-Peteroa Stromboli
Ahyi Cuicocha Iliwerung Llaima Poas Sulu Range
Aira Cumbal Inielika Lokon-Empung Popocatepetl Sumbing
Akan Dabbahu Ioto Lonquimay Purace Sumisujima
Alaid Davidof Irazu Lopevi Puyehue-Cordon Caulle Sundoro
Alu-Dalafilla Dempo Iya Machin Rabaul Suoh
Ambae Descabezado Grande Izu-Torishima Makushin Raikoke Suretamatai
Ambang Dieng Volcanic Complex Jackson Segment Maly Semyachik Ranakah Suwanosejima
Ambrym Dukono Kaba Manam Raoul Island Taal
Anatahan East Epi Kadovar Manda Hararo Rasshua Tair, Jebel at
Aniakchak Ebeko Kaitoku Seamount Marapi Raung Takawangha
Antillanca Volcanic Complex Ebulobo Kama'ehuakanaloa Maroa Redoubt Talang
Antuco Edgecumbe Kambalny Martin Reventador Tambora
Apoyeque Egon Kanaga Masaya Reykjanes Tanaga
Arenal Ekarma Kanlaon Matthew Island Rincon de la Vieja Tandikat-Singgalang
Asamayama Eldey Karangetang Maule, Laguna del Rinjani Tangkoko-Duasudara
Askja Erebus Karkar Mauna Loa Ritter Island Tangkuban Parahu
Asosan Erta Ale Karthala Mayon Rotorua Tara, Batu
Atka Volcanic Complex Etna Karymsky McDonald Islands Ruang Ta'u
Augustine Etorofu-Yakeyama [Grozny Group] Kasatochi Melebingoy Ruapehu Taupo
Avachinsky Eyjafjallajokull Katla Melimoyu Ruby Telica
Awu Fagradalsfjall Katmai Merapi Ruiz, Nevado del Tenerife
Axial Seamount Fernandina Kavachi Midagahara Sabancaya Tengger Caldera
Azul, Cerro Fogo Kelimutu Misti, El Sakar Three Sisters
Azumayama Fonualei Kelud Miyakejima Salak Tinakula
Bagana Fournaise, Piton de la Kerinci Momotombo San Cristobal Tofua
Balbi Fourpeaked Ketoi Monowai San Miguel Tokachidake
Bamus Fuego Kharimkotan Montagu Island San Vicente Tolbachik
Banda Api Fujisan Kick 'em Jenny Moyorodake [Medvezhia] Sangay Toliman
Bardarbunga Fukutoku-Oka-no-Ba Kie Besi Mutnovsky Sangeang Api Tongariro
Barren Island Galeras Kikai Myojinsho Santa Ana Trident
Batur Galunggung Kilauea Nabro Santa Maria Tungurahua
Bezymianny Gamalama Kirishimayama Negra, Sierra Sao Jorge Turrialba
Bogoslof Gamkonora Kita-Ioto Negro, Cerro Sarigan Ubinas
Brava Gareloi Kizimen Nightingale Island Sarychev Peak Ugashik-Peulik
Bristol Island Gaua Klyuchevskoy Nishinoshima Saunders Ukinrek Maars
Bulusan Gorely Kolokol Group Nisyros Savo Ulawun
Calbuco Great Sitkin Koryaksky Novarupta Semeru Unnamed
Callaqui Grimsvotn Krakatau NW Rota-1 Semisopochnoi Unnamed
Cameroon Guagua Pichincha Krummel-Garbuna-Welcker Nyamulagira Seulawah Agam Veniaminof
Campi Flegrei Guallatiri Krysuvik-Trolladyngja Nyiragongo Sheveluch Villarrica
Campi Flegrei del Mar di Sicilia Guntur Kuchinoerabujima Ofu-Olosega Shishaldin Vulcano
Cayambe Hachijojima Kurikomayama Okataina Simbo West Mata
Chachadake [Tiatia] Hakoneyama Kusatsu-Shiranesan Okmok Sinabung Westdahl
Chaiten Heard Kverkfjoll Ontakesan Sinarka Whakaari/White Island
Chiginagak Hekla La Palma Oraefajokull Siple Witori
Chikurachki Helgrindur Lamington Osorno Sirung Wolf
Chiles-Cerro Negro Hierro Lamongan Pacaya Slamet Wrangell
Chillan, Nevados de Hokkaido-Komagatake Langila Pagan Snaefellsjokull Yakedake
Chirinkotan Home Reef Lanin Palena Volcanic Group Soputan Yasur
Chirpoi Hood Lascar Paluweh Sorikmarapi Yellowstone
Ciremai Huaynaputina Late Panarea Sotara Yufu-Tsurumi
Cleveland Hudson, Cerro Lateiki Papandayan Soufriere Hills Zaozan [Zaosan]
Colima Huila, Nevado del Lengai, Ol Doinyo Pavlof Soufriere St. Vincent Zavodovski
Colo Hunga Tonga-Hunga Ha'apai Leroboleng Pelee South Sarigan Seamount Zhupanovsky
Concepcion Ibu Lewotobi Peuet Sague Spurr Zubair Group
Copahue Ijen Lewotolok Pinatubo St. Helens
 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 Chikurachki
Based on observations of satellite imagery, an ash plume from Chikurachki drifted about 120 km to the SE on 19 August. KVERT raised the Level of Concern Color Code from Green to Orange. The Tokyo VAAC reported that ash plumes rose to altitudes of 4.3-5.2 km (14,000-17,000 ft) a.s.l. during 20-21 August, based on observations of satellite imagery and information from KVERT.
Sources: Tokyo Volcanic Ash Advisory Center (VAAC), Kamchatkan Volcanic Eruption Response Team (KVERT)
Report for Karangetang
The Alert Status of Karangetang was raised on 18 August from 3 to 4 (on a scale of 1-4) due to increased eruptive activity, based on visual observation and increased seismicity. According to news articles, lava flowed about 1 km down the S slope and "booming" noises were heard. Thick ashfall covered villages, farms, and trees on the slopes.
Sources: The Jakarta Post, Reuters, Agence France-Presse (AFP), Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
Report for Kilauea
HVO reported that fissure segment D from Kilauea's 21 July fissure eruption continued to feed an advancing 'a'a lava flow during 15-21 August. Aerial observations on 17 August revealed that the first 'a'a flow had advanced 24 m since 13 August but was inactive. The second 'a'a channel had advanced 2.3 km along the N side of the first flow. Smoke from burning vegetation was visible near the flow front. On 18 August, a new and widening crack was seen on the rim of Pu'u 'O'o crater. A few small earthquakes were located beneath the summit, Halema'uma'u crater, and the S flank.

On 14 August, approximately 17.8 hectares (44 acres) of the East Lae'apuki bench collapsed, possibly due to a M 5.4 earthquake, high surf from hurricane Flossie, or a combination of both.
Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
Report for Manda Hararo
A large sulfur dioxide plume and several thermal anomalies from Manda Hararo were detected in satellite imagery on 13 August. On 16 August, a field team conducted aerial and ground observations of a locality known as Karbahi, a graben area with numerous active faults, fissures, and basalt flows, NW of the center of Manda Hararo. Observations revealed active volcanism, including isolated areas of intense gas emission and visible sulfur deposits. Basaltic lava flowed from long fissures, predominantly to the W of the graben floor. Each fissure was covered by a continuous row of small and closely spaced spatter and scoria cones 2-10 m high. Spatter and scoria deposits ranged in size from coarse lapilli to bombs. Incandescence and occasionally small flames were emitted from the tops of some of the cones.

Observed 'a'a and pahoehoe flows traveled a few hundred meters from the vents. The overall thickness of the flows varied but reached several meters in places. Lava channels and lava tubes were abundant. Fault scarps with fresh breaks and rockfalls were noted. The area affected by tectonic and volcanic activity was an estimated 5-7 km long and 1 km wide.

According to eye-witness accounts, a cracking sound was heard and a tremor was felt on 12 August. On 13 August, "fire" was seen that lit up a large area. "Fire and smoke" continued with variable intensity until 16 August. No damage to life or property was reported.
Sources: Simon Carn, Gezahegn Yirgu, Atalay Ayele, Shimeles Fisseha, Tadiwos Chernet and Ato Kifle Damtew, Addis Ababa University, Ethiopia
Report for Pavlof
AVO raised the Volcanic Alert Level to Advisory and the Aviation Color Code to Yellow for Pavlof on 14 August due to an abrupt increase in seismicity. During 14-15 August, a strong thermal anomaly was detected in the crater and prompted AVO to again raise the Volcanic Alert Level/ Aviation Color Code, to Watch/Orange. According to eye witnesses aboard a ship on 15 August, incandescent blocks rolled down the ESE flank and lava-fountaining occurred on the SE flank. The presence of lava was confirmed using satellite imagery. Pilots reported that the flanks were covered with ash and that an ash plume rose to an altitude of 2.6 km (8,400 ft) a.s.l. and drifted SW.

On 16 August, residents of Cold Bay, about 60 km SW, and of Sand Point, about 97 km ESE, saw incandescence at the summit. A strong thermal anomaly was present at the summit on satellite imagery. Seismicity increased in intensity and possibly indicated a lahar on the SE flank.

During 17-20 August, seismicity continued at high levels. Explosions were recorded and seismic signals possibly indicated flow events such as lahars. A strong thermal anomaly continued to be present at the summit. Aerial and ground observations revealed a vigorous eruption of lava during 18-20 August. Members of an AVO field party saw a lahar on the SE flank on 20 August.
Source: US Geological Survey Alaska Volcano Observatory (AVO)
Report for Cleveland
Clouds obscured satellite and web camera views of Cleveland volcano during 15-20 August. A clear view of the crater on 20 August revealed a thermal anomaly at the summit. The Aviation Color Code remained at Orange and the Volcano Alert Level remained at Watch.
Source: US Geological Survey Alaska Volcano Observatory (AVO)
Report for Fuego
Based on a Guatemala City surface report, the Washington VAAC reported activity at Fuego. A hotspot was visible on satellite imagery.
Source: Washington Volcanic Ash Advisory Center (VAAC)
Report for Karymsky
Seismic activity at Karymsky was above background levels during 10-17 August, with 350-600 shallow earthquakes occurring daily. Based on seismic interpretation, ash plumes may have risen to an altitude of 3 km (9,800 ft) a.s.l. The Level of Concern Color Code remained at Orange.
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Report for Klyuchevskoy
On 17 August, KVERT reported that seismic activity at Kliuchevskoi was at background levels during the past five weeks, and ash plumes had not been noted for the last four weeks. Satellite imagery showed a thermal anomaly on 11 August. The Level of Concern Color Code was lowered from Yellow to Green.
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Report for Manam
Based on satellite image observations and information from RVO, the Darwin VAAC reported that an eruption plume from Manam rose to an altitude of 3 km (10,000 ft) a.s.l. on 10 August and drifted W. On 21 August, an ash plume again rose to an altitude of 3 km (10,000 ft) a.s.l. as indicated by observations of satellite imagery. The plume drifted SW.
Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Report for Rabaul
RVO reported that ash plumes from Rabaul caldera's Tavurvur cone rose to an altitude of 1.1 km (3,600 ft) a.s.l. on 15 August and drifted NNW. The ash emissions were accompanied by roaring noises. Ashfall was reported in Rabaul Town and surrounding areas. White vapor plumes noted during 14-20 August were occasionally accompanied by blue vapor plumes. Vapor plumes rose to an altitude of 1.7 km (5,600 ft) a.s.l. on 20 August and drifted WNW.
Source: Rabaul Volcano Observatory (RVO)
Report for Sangay
Based on pilot observations, the Washington VAAC reported that an ash plume from Sangay drifted SSE on 19 August. Observations using satellite imagery were inhibited due to cloud cover.
Source: Washington Volcanic Ash Advisory Center (VAAC)
Report for Sheveluch
KVERT reported that seismic activity at Shiveluch was slightly above background levels during 10-17 August. Based on seismic interpretation, avalanches and ash plumes that rose to an altitude of 10 km (32,800 ft) a.s.l. occurred during the reporting period. Growth of the E part of the lava dome, summit incandescence, and incandescent avalanches were visible from the town of Klyuchi, about 50 km SW, during 11-12 August. A diffuse ash plume was visible on satellite imagery drifting SE on 11 August. On 14 August, two avalanches were accompanied by ash plumes that rose to an altitude of 4.5 km (14,800 ft) a.s.l. and drifted NW. Observations of satellite imagery revealed that a thermal anomaly was present in the crater during 10-17 August. The Level of Concern Color Code remained at Orange.

Based on information reported from KEMSD, the Tokyo VAAC reported that an eruption plume rose to 5.2 km (17,000 ft) a.s.l. on 21 August. Ash was not identified on satellite imagery.
Sources: Tokyo Volcanic Ash Advisory Center (VAAC), Kamchatkan Volcanic Eruption Response Team (KVERT)
Report for Soufriere Hills
MVO reported that during 13-21 August the lava dome at Soufrière Hills changed very little, based on visual observations. Seismic activity was very low and low-level rockfall activity continued. The Alert Level remained elevated at 4 (on a scale of 0-5).
Source: Montserrat Volcano Observatory (MVO)
Report for St. Helens
Data from deformation-monitoring instruments indicated that during 15-21 August lava-dome growth at Mount St. Helens continued. Seismicity persisted at low levels, punctuated by M 1.5-2.5, and occasionally larger, earthquakes. In some instances, clouds inhibited visual observations.
Source: US Geological Survey Cascades Volcano Observatory (CVO)
Report for Tungurahua
Based on seismic interpretation, IG reported explosions and ash emissions from Tungurahua during 15-21 August. During 17-18 August, roaring and "cannon shot" noises were reported and ashfall occurred in areas to the W and SW. On 19 August, "cannon shot" noises were again reported and a gas-and-ash plume rose to an altitude of 5.5 km (18,000 ft) a.s.l. and drifted W. Explosions on 20 and 21 August rattled windows at the Tungurahua Observatory (OVT) in Guadalupe, 11 km N, and in houses in areas to the W. Ashfall was reported in areas to the SW on 21 August. Inclement weather inhibited visual observations on other days.
Source: Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN)