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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 9 August-15 August 2023
Name Location Eruption Start Date Report Status
Bagana Bougainville (Papua New Guinea) 2000 Feb 28 (in or before) New
Poas Costa Rica 2023 Dec 1 New
Shishaldin Fox Islands (USA) New
Ulawun New Britain (Papua New Guinea) New
Aira Kyushu (Japan) 2017 Mar 25 Continuing
Ebeko Paramushir Island (Russia) 2022 Jun 11 Continuing
Fuego South-Central Guatemala 2002 Jan 4 Continuing
Great Sitkin Andreanof Islands (USA) 2021 May 25 Continuing
Ibu Halmahera 2008 Apr 5 Continuing
Klyuchevskoy Central Kamchatka (Russia) Continuing
Lewotolok Lembata Island 2020 Nov 27 Continuing
Mayon Luzon (Philippines) 2023 Apr 27 ± 2 days Continuing
Merapi Central Java 2020 Dec 31 Continuing
Piton de la Fournaise Reunion Island (France) Continuing
Popocatepetl Mexico 2005 Jan 9 Continuing
Santa Maria Southwestern Guatemala 1922 Jun 22 Continuing
Semeru Eastern Java 2017 Jun 6 Continuing
Sheveluch Central Kamchatka (Russia) 1999 Aug 15 Continuing
Suwanosejima Ryukyu Islands (Japan) 2004 Oct 23 Continuing
Ubinas Peru Continuing
All times are local unless otherwise stated.
Weekly Reports Archive

Since the Weekly Volcanic Activity Report began in November 2000, there have been 20,047 individual reports over 1,217 weeks (average of 16 per week) on 332 different volcanoes.

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Agung Cuicocha Iliwerung Llaima Popocatepetl Sumbing
Ahyi Cumbal Inielika Lokon-Empung Purace Sundoro
Aira Dabbahu Ioto Lonquimay Puyehue-Cordon Caulle Suretamatai
Akan Davidof Irazu Lopevi Rabaul Suwanosejima
Alaid Dempo Iya Machin Raikoke Taal
Alu-Dalafilla Descabezado Grande Izu-Torishima Makushin Ranakah Tair, Jebel at
Ambae Dieng Volcanic Complex Jackson Segment Maly Semyachik Raoul Island Takawangha
Ambang Dukono Kaba Manam Rasshua Talang
Ambrym East Epi Kadovar Manda Hararo Raung Tambora
Anatahan Ebeko Kaitoku Seamount Marapi Redoubt Tanaga
Aniakchak Ebulobo Kama'ehuakanaloa Maroa Reventador Tandikat-Singgalang
Antillanca Volcanic Complex Edgecumbe Kambalny Martin Reykjanes Tangkoko-Duasudara
Antuco Egon Kanaga Masaya Rincon de la Vieja Tangkuban Parahu
Apoyeque Ekarma Kanlaon Maule, Laguna del Rinjani Tara, Batu
Arenal Eldey Karangetang Mauna Loa Ritter Island Ta'u
Asamayama Erebus Karkar Mayon Rotorua Taupo
Askja Erta Ale Karthala McDonald Islands Ruang Telica
Asosan Etna Karymsky Melebingoy Ruapehu Tenerife
Atka Volcanic Complex Etorofu-Yakeyama [Grozny Group] Kasatochi Melimoyu Ruby Tengger Caldera
Augustine Eyjafjallajokull Katla Merapi Ruiz, Nevado del Three Sisters
Avachinsky Fagradalsfjall Katmai Midagahara Sabancaya Tinakula
Awu Fernandina Kavachi Misti, El Sakar Tofua
Axial Seamount Fogo Kelimutu Miyakejima Salak Tokachidake
Azul, Cerro Fonualei Kelud Momotombo San Cristobal Tolbachik
Azumayama Fournaise, Piton de la Kerinci Monowai San Miguel Toliman
Bagana Fourpeaked Ketoi Montagu Island San Vicente Tongariro
Balbi Fuego Kharimkotan Moyorodake [Medvezhia] Sangay Trident
Bamus Fujisan Kick 'em Jenny Mutnovsky Sangeang Api Tungurahua
Banda Api Fukutoku-Oka-no-Ba Kie Besi Myojinsho Santa Ana Turrialba
Bardarbunga Galeras Kikai Nabro Santa Maria Ubinas
Barren Island Galunggung Kilauea Negra, Sierra Sao Jorge Ugashik-Peulik
Batur Gamalama Kirishimayama Negro, Cerro Sarigan Ukinrek Maars
Bezymianny Gamkonora Kita-Ioto Nightingale Island Sarychev Peak Ulawun
Bogoslof Gareloi Kizimen Nishinoshima Saunders Unnamed
Brava Gaua Klyuchevskoy Nisyros Savo Unnamed
Bristol Island Gorely Kolokol Group Novarupta Semeru Veniaminof
Bulusan Great Sitkin Koryaksky NW Rota-1 Semisopochnoi Villarrica
Calbuco Grimsvotn Krakatau Nyamulagira Seulawah Agam Vulcano
Callaqui Guagua Pichincha Krummel-Garbuna-Welcker Nyiragongo Sheveluch West Mata
Cameroon Guallatiri Krysuvik-Trolladyngja Ofu-Olosega Shishaldin Westdahl
Campi Flegrei del Mar di Sicilia Guntur Kuchinoerabujima Okataina Simbo Whakaari/White Island
Cayambe Hachijojima Kurikomayama Okmok Sinabung Witori
Chachadake [Tiatia] Hakoneyama Kusatsu-Shiranesan Ontakesan Sinarka Wolf
Chaiten Heard Kverkfjoll Oraefajokull Siple Wrangell
Chiginagak Hekla La Palma Osorno Sirung Yakedake
Chikurachki Helgrindur Lamington Pacaya Slamet Yasur
Chiles-Cerro Negro Hierro Lamongan Pagan Snaefellsjokull Yufu-Tsurumi
Chillan, Nevados de Hokkaido-Komagatake Langila Palena Volcanic Group Soputan Zaozan [Zaosan]
Chirinkotan Home Reef Lanin Paluweh Sorikmarapi Zavodovski
Chirpoi Hood Lascar Panarea Sotara Zhupanovsky
Ciremai Huaynaputina Late Papandayan Soufriere Hills Zubair Group
Cleveland Hudson, Cerro Lateiki Pavlof Soufriere St. Vincent
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
Cotopaxi Iliamna Little Sitkin Poas Sulu Range
 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 Bagana
The Darwin VAAC reported that ash plumes from Bagana were visible in satellite images rising to 2.1 km (7,000 ft) a.s.l. at 0800 on 12 August and 3 km (10,000 ft) a.s.l. a few hours later at 1220; the plumes drifted NW and W, respectively. According to a news report aid has been sent to the more than 6,300 people that have been adversely affected by the recent explosive eruptions at Bagana. The report noted that as many as 17,000 residents living near the volcano may be impacted.
Sources: Darwin Volcanic Ash Advisory Centre (VAAC), US Agency for International Development / Bureau for Humanitarian Assistance
Report for Poas
OVSICORI-UNA reported that fumarolic degassing and lake convection at Poás were visible during 9-15 August. A small phreatic eruption at the center of the lake ejected material 5 m above the lake at 0842 on 11 August.
Source: Observatorio Vulcanologico y Sismologico de Costa Rica-Universidad Nacional (OVSICORI-UNA)
Report for Shishaldin
AVO reported that the effusive and explosive eruption at Shishaldin continued during 9-15 August. Seismicity was generally low during 9-14 August with a few local earthquakes detected on some days; no significant explosive activity was observed in seismic or infrasound data. Elevated surface temperatures were observed in satellite images caused by a small lava flow at the summit. Minor steam-and-gas emissions were visible in webcam or satellite images, though weather clouds sometimes prevented views. At 1827 on 14 August AVO noted that seismic tremor had steadily increased during the afternoon and erupting lava at the summit was evident in a satellite image. Explosion signals began to be detected at 0200 on 15 August. By 0335 satellite images showed an ash cloud drifting NE at 7.6 km (25,000 ft) a.s.l. and lightning was detected in the vicinity of the volcano. The ash cloud drifted 100 km NE over the Bering Sea and may have risen as high as 11 km (36,000 ft) a.s.l. Seismicity was significantly elevated during the eruption but had declined by 1322, though levels continued to indicate ongoing, low-level activity; a pilot reported that ash emissions continued, rising as high as 4.9 km (16,000 ft) a.s.l. The Volcano Alert Level remained at Watch (the third level on a four-level scale) and the Aviation Color Code remained at Orange (the third color on a four-color scale).
Source: US Geological Survey Alaska Volcano Observatory (AVO)
Report for Ulawun
Rabaul Volcano Observatory (RVO) reported that small-to-moderate volumes of white steam-and-gas plumes were visible in webcam images rising from Ulawun’s summit during 4-6 August. On the rest of the days through 12 August weather conditions mostly prevented views of the summit. No audible sounds or nighttime crater incandescence were reported. RSAM fluctuated during 4 July-12 August but overall showed an upward trend and corresponded to an increase in volcanic tremor amplitudes. RVO warned that minor eruptive activity may occur if the trend continued and that ash emissions had previously occurred at similar RSAM levels. The Alert Level remained at Stage 1 (the lowest level on the four-level scale).
Source: Rabaul Volcano Observatory (RVO)
Report for Aira
JMA reported ongoing activity at Minamidake Crater (Aira Caldera’s Sakurajima volcano) during 7-14 August. Flashes of incandescence at Minamidake were observed during the night on 7 August. An explosion at 0345 on 9 August ejected large blocks as far as 600 m from the vent and possibly produced an ash plume, though weather conditions prevented visual confirmation. An explosion at 2205 on 13 August produced an ash plume that rose 2 km above the crater rim and drifted W. Large blocks were ejected 300-500 m from the vent. The Alert Level remained at 3 (on a 5-level scale), and the public was warned to stay 2 km away from both craters.
Source: Japan Meteorological Agency (JMA)
Report for Ebeko
KVERT reported that a moderate explosive activity at Ebeko was ongoing during 3-10 August. According to volcanologists in Severo-Kurilsk (Paramushir Island, about 7 km E), explosions during 5-6 and 8-9 August generated ash plumes that rose as high as 3.5 km (11,500 ft) a.s.l and drifted to the S and SE. Thermal anomalies were identified in satellite images during 6-9 August; weather clouds obscured views on other days. The Aviation Color Code remained at Orange (the third level on a four-color scale). Dates are based on UTC times; specific events are in local time where noted.
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Report for Fuego
INSIVUMEH reported that 3-10 explosions per hour were recorded at Fuego during 9-15 August, generating ash plumes that rose as high as 1.1 km above the crater rim. The ash plumes drifted as far as 30 km NW, W, and SW causing daily ashfall in areas downwind including Morelia (9 km SW), Panimaché I and II (8 km SW), Santa Sofía (12 km SW), El Porvenir (8 km ENE), Los Yucales (12 km SW), Sangre de Cristo (8 km WSW), El Porvenir (8 km ENE), San Pedro Yepocapa (8 km NW), and Acatenango (8 km E). Daily shock waves rattled structures in communities around the volcano and rumbling was sometimes heard. Daily block avalanches descended the Ceniza (SSW), Seca (W), Trinidad (S), Taniluyá (SW), Honda, Las Lajas (SE), and El Jute (ESE) drainages. On most days explosions ejected incandescent material as high as 200 m above the summit.
Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Report for Great Sitkin
AVO reported that slow lava effusion continued at Great Sitkin during 9-15 August, producing a thick flow in the summit crater. The eastern lobe continued to advance into glacial ice surrounding the crater, causing the ice to deform and crack, based on a 10 August satellite image. Seismicity remained slightly elevated throughout the week. Weather clouds often obscured satellite and webcam views. The Volcano Alert Level remained at Watch (the third level on a four-level scale) and the Aviation Color Code remained at Orange (the third color on a four-color scale).
Source: US Geological Survey Alaska Volcano Observatory (AVO)
Report for Ibu
PVMBG reported that Ibu continued to erupt during 9-15 August. Daily white-and-gray ash emissions generally rose as high as 600 m above the summit and drifted N and NE. Gray ash plumes rose to 1 km on 9 August and as high as 1.5 km on 11 August that drifted N and NE. The Alert Level remained at a 2 (the second highest level on a four-level scale), and the public was advised to stay outside of the 2 km hazard zone, and to stay 3.5 km away from the N area of the active crater.
Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
Report for Klyuchevskoy
KVERT reported that the explosive Strombolian eruption at Klyuchevskoy continued during 3-10 August and a daily bright thermal anomaly was identified in satellite images. Lava advanced down the Apakhonchich drainage on the SE flank. The Aviation Color Code remained at Yellow (the second level on a four-color scale).
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Report for Lewotolok
PVMBG reported that the eruption at Lewotolok continued during 9-15 August. On most days white steam-and-gas plumes rose as high as 500 m above the summit and drifted W and NW. Incandescence at the summit was visible in a webcam image from 11 August. Variable density gray ash plumes rose 500-800 m and drifted W and NW during 11-12 August. The Alert Level remained at 2 (on a scale of 1-4) and the public was warned to stay at least 2 km away from the summit crater.
Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
Report for Mayon
PHIVOLCS reported that the eruption at Mayon continued during 9-15 August, with slow lava effusion from the summit crater feeding flows on the S, SE, and E flanks. The length of the lava flow in the Mi-Isi (S) drainage remained at 2.8 km and the flow in the Bonga (SE) drainage was 3.4 km long. The advancing flow in the Basud (E) drainage reached 1 km long by 9 August and was 1.1 km by 13 August. Collapses at the lava dome and from the lava flows produced incandescent rockfalls and pyroclastic density currents (PDCs, or pyroclastic flows) that descended the Mi-Isi, Bonga, and Basud drainages as far as 4 km. Each day seismic stations recorded 45-201 rockfall events and 1-4 PDC events. There 42-259 volcanic earthquakes, including 42-91 low-frequency volcanic earthquakes and 56-167 tremor events, each with durations of 1-45 minutes. Sulfur dioxide emissions were reported on most days, averaging between 799 and 2,689 tonnes per day, with the highest value recorded on 10 August. There was a total of five emissions of short, dark ash plumes (called “ashing” by PHIVOLCS) during 10-12 August. The Alert Level remained at 3 (on a 0-5 scale) and residents were reminded to stay away from the 6-km-radius Permanent Danger Zone (PDZ). PHIVOLCS recommended that civil aviation authorities advise pilots to avoid flying close to the summit.
Source: Philippine Institute of Volcanology and Seismology (PHIVOLCS)
Report for Merapi
BPPTKG reported that the eruption at Merapi (on Java) continued during 4-10 August and seismicity remained at elevated levels. The SW lava dome produced a total of 198 lava avalanches that descended the SW flank; 15 traveled as far as 1.9 km down the upper part of the Boyong drainage, 180 traveled as far as 2 km down the upper Bebeng drainage, and 3 traveled as far as 1.6 km down the Sat/Putih drainage. Morphological changes to the SW lava dome were due to continuing collapses of material. Temperatures of the SW dome ranged from 180 to 412 degrees Celsius based on analysis of thermal photos acquired on 9 August. Analysis of a 10 August aerial survey estimated that the SW dome volume was 2,764,300 cubic meters and the dome in the main crater was an estimated 2,369,800 cubic meters. The Alert Level remained at 3 (on a scale of 1-4), and the public was warned to stay 3-7 km away from the summit based on location.
Source: Balai Penyelidikan dan Pengembangan Teknologi Kebencanaan Geologi (BPPTKG)
Report for Piton de la Fournaise
OVPF reported that the eruption at Piton de la Fournaise ended at 0500 on 10 August. The amplitude of volcanic tremor (an indicator of lava and gas emissions) had declined during the previous week. The Alert Level remained at 2-1, signifying an “ongoing eruption” inside the Enclos Fouqué caldera.
Source: Observatoire Volcanologique du Piton de la Fournaise (OVPF)
Report for Popocatepetl
CENAPRED reported that eruptive activity continued at Popocatépetl during 8-15 August. Long-period events totaling 19-185 per day were accompanied by steam-and-gas plumes that sometimes contained minor amounts of ash. Seismic activity also included volcanic tremors (3-15 minutes daily), a few minor explosions, and two volcano-tectonic earthquakes on 9 and 15 August. A minor explosion at 0305 on 11 August was accompanied by crater incandescence. Another explosion at 0618 on 13 August produced an ash, steam, and gas plume that rose above the summit, and at 0736 an explosion produced a puff of ash, steam, and gas. The Alert Level remained at Yellow, Phase Two (the middle level on a three-color scale) and the public was warned to stay 12 km away from the crater.
Source: Centro Nacional de Prevencion de Desastres (CENAPRED)
Report for Santa Maria
INSIVUMEH reported that eruptive activity continued at Santa Maria’s Santiaguito lava dome complex during 9-15 August. Incandescence from the dome was visible during most nights and early mornings, and occasionally from the SW lava flow. Lava extrusion continued and formed a more prominent high point in the middle of the dome that was the main source of collapses and occasional short pyroclastic flows. Daily weak-to-moderate explosions generated gas-and-ash plumes that rose 700-1,000 m above the dome and drifted NW, W, and SW. Explosions also triggered incandescent avalanches that descended the dome’s flanks in all directions, and into the Zanjón, Seco, and San Isidro drainages. Incandescence was observed at the crater and along lava flow margins during the night and early morning.
Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Report for Semeru
PVMBG reported that eruptive activity continued at Semeru during 9-15 August. White-and-gray ash plumes rose as high as 1 km above the summit and drifted in multiple directions on most days; weather clouds prevented views on 14 August. Some of the plumes were brownish during 11-12 August. The Alert Level remained at 3 (third highest on a scale of 1-4). The public was warned to stay at least 5 km away from the summit in all directions, 13 km from the summit to the SE, 500 m from the banks of the Kobokan drainage as far as 17 km from the summit, and to avoid other drainages including the Bang, Kembar, and Sat, due to lahar, avalanche, and pyroclastic flow hazards.
Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
Report for Sheveluch
KVERT reported that the eruption at Sheveluch continued during 3-10 August. Intense fumarolic activity was visible at the active dome, and thermal anomalies were identified in satellite images during 5-7 and 9 August. The Aviation Color Code remained at Orange (the third level on a four-color scale). Dates are based on UTC times; specific events are in local time where noted.
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Report for Suwanosejima
JMA reported that the eruption at Suwanosejima's Ontake Crater continued during 7-14 August. An eruptive event produced a plume that rose 1 km above the crater rim at 1447 on 12 August. No explosions or ejecta were observed during this time period. The Alert Level remained at 2 (on a 5-level scale) and the public was warned to stay at least 1 km away from the crater.
Source: Japan Meteorological Agency (JMA)
Report for Ubinas
Instituto Geofísico del Perú (IGP) and Instituto Geológico Minero y Metalúrgico (INGEMMET) reported that the eruption at Ubinas continued during 7-13 August. According to IGP a daily average of 102 volcano-tectonic earthquakes indicating rock fracturing and 60 long-period earthquakes signifying the movement of gas and magma. An explosion on 10 August produced an ash plume that rose 2.4 km above the crater rim and drifted 25 km SE and E. Ashfall was reported in Ubinas, Matalaque, and Chojata. INGEMMET noted that sulfur dioxide emissions were at moderate levels during 10-11 and 13-14 August, averaging 2,400-3,700 tons per day. Ash-and-steam plumes rose as high as 800 m and drifted E, SE, S, and W during 13-14 August. The Alert Level remained at Orange (the third level on a four-color scale) and the public was warned to stay 4 km away from the crater.
Sources: Instituto Geofísico del Perú (IGP), Instituto Geológico Minero y Metalúrgico (INGEMMET)