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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, notices of volcanic activity posted on these pages are preliminary and subject to change as events are studied in more detail.

This is not a comprehensive list of all of Earth's volcanoes erupting during the week, but rather a summary of activity that meet criteria discussed in detail in the "Criteria and Disclaimers" section. Carefully reviewed, detailed narratives on various volcanoes are published as reports of the Bulletin of the Global Volcanism Network.

Smithsonian / USGS Weekly Volcanic Activity Report for the week of 29 July-4 August 2015
Name Location Eruption Start Date Report Status
Cleveland Chuginadak Island (USA) New
Colima Mexico New
Gamalama Halmahera (Indonesia) New
Manam Papua New Guinea 2014 Jun 29 New
Nevado del Ruiz Colombia 2017 Dec 18 New
Piton de la Fournaise Reunion Island (France) New
Raung Eastern Java (Indonesia) 2020 Jul 16 New
Suwanosejima Ryukyu Islands (Japan) 2004 Oct 23 New
Dukono Halmahera (Indonesia) 1933 Aug 13 Continuing
Karangetang Siau Island (Indonesia) 2018 Nov 25 Continuing
Karymsky Eastern Kamchatka (Russia) Continuing
Kilauea Hawaiian Islands (USA) Continuing
Sheveluch Central Kamchatka (Russia) 1999 Aug 15 Continuing
Shishaldin Fox Islands (USA) Continuing
Sinabung Indonesia 2020 Aug 8 Continuing
Tungurahua Ecuador Continuing
Weekly Reports Archive

Since the Weekly Volcanic Activity Report began in November 2000, there have been 16,153 individual reports over 1,038 weeks (average of 16 per week) on 307 different volcanoes.

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


Download Smithsonian / USGS Weekly Volcanic Activity Report Network RSS Feed

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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Download Smithsonian/USGS Weekly Volcanic Activity Report Network Link Download Smithsonian / USGS Weekly Volcanic Activity Report Network Link

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 Cleveland
AVO reported that during 29 July-4 August satellite images detected strongly elevated surface temperatures at Cleveland's summit consistent with growth of a new lava dome. A field crew working in the area on 1 August reported frequent rockfalls on the volcano. A weak infrasound signal was much smaller than the explosion detected on 21 July; the signal may have been related to gas emissions, also consistent with lava-dome effusion. A very small gas plume was visible in webcam images during 2-3 August, and steam emissions were observed on 4 August. 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 Colima
Based on satellite images and the Mexico City MWO, the Washington VAAC reported that multiple ash plumes from Colima rose to an altitude of 5.5 km (15,000 ft) a.s.l. and drifted 110 km WSW and SW on 31 July. On 3 August a gas plume possibly containing ash drifted 30-40 km N and W. The next day an ash plume rose to an altitude of 6.1 km (20,000 ft) a.s.l. and drifted over 35 km NW.
Source: Washington Volcanic Ash Advisory Center (VAAC)
Report for Gamalama
On 4 August, BNPB reported that Gamalama continued to erupt, although with low intensity. Tremor was continuous. The Alert Level remained at 2 (on a scale of 1-4); visitors and residents were warned not to approach the crater within a radius of 1.5 km. The total number of evacuees in shelters was 1,791. Based on local observations, a SIGMET and wind data, and satellite images, the Darwin VAAC reported that an ash plume drifted over 20 km NW on 4 August.
Sources: Badan Nacional Penanggulangan Bencana (BNPB), Darwin Volcanic Ash Advisory Centre (VAAC)
Report for Manam
RVO reported that an eruption at Manam's Southern Crater began at about 1130 on 31 July with low roaring noises. Soon after, variously-sized scoria were ejected; fist-sized scoria fell in Warisi village on the E side of the island, and clasts 10-20 cm in diameter fell on the N side of the island in Baliau. Two people were knocked unconscious after being hit with scoria. According to a news article residents started evacuating around midday. Residents in Bogia (25-30 km SSW of Manam on the N coast of the mainland) reported ashfall at around 1245, and by 1300 the sky was darker. Ashfall was also reported in Potsdam (on the coast, NW of Bogia). RVO stated that at around 1330, immediately after scoria fall ceased, dark gray ash emissions rose from the crater. Based on satellite images and ground observations, the Darwin VAAC reported that the ash plume rose to an altitude of 19.8 km (65,000 ft) a.s.l., spread out in multiple directions, and then drifted 370 km SW. By 1740 RVO noted that activity had declined and emission turned to light gray, and by the next morning only dense white emission were observed.
Sources: Rabaul Volcano Observatory (RVO), Darwin Volcanic Ash Advisory Centre (VAAC), Loop
Report for Nevado del Ruiz
The Washington VAAC reported bright thermal anomalies at Nevado del Ruiz visible in satellite images on 31 July; a brief increase in seismicity was detected, and the thermal anomaly was weaker in subsequent images.
Source: Washington Volcanic Ash Advisory Center (VAAC)
Report for Piton de la Fournaise
OVPDLF reported that a sharp increase in seismicity at Piton de la Fournaise, increased gas emissions, and deformation recorded on 30 July prompted an Alert Level increase and an evacuation. A fissure eruption began the next day at 0920, preceded by 90 minutes of high seismicity and 80 minutes of major deformation; it was confirmed by a hiker and then by observation of a gas plume. A 1-km-long fissure opened in the NE part of the l'Enclos Fouqué caldera and produced dozens of lava fountains. Based on satellite images and gas data the flow rate was estimated to be 28 cubic meters per second initially and then 11 cubic meters per second later that day. A gas plume rose to altitudes of 3.2-3.5 km (10,500-11,500 ft) a.s.l. By the evening there were only five fountains, and a lava flow had traveled as far E as Plaine des Osmondes (NE part of the caldera). According to a news article, lava fountains were 40 m high, forming 20-m-high cones on 31 July. At 1115 on 2 August tremor stopped, after several hours of fluctuating intensity, and lava was no longer being effused.
Sources: Observatoire Volcanologique du Piton de la Fournaise (OVPF), The Island Packet
Report for Raung
On 4 August BNPB reported that during the previous three days the Strombolian eruption at Raung increased in intensity. Ash fell in Sempu, Songgon, Glenmore, Gambiran, and Banyuwangi. On 4 August dense blackish gray ash plumes rose 800 m and drifted SE. Based on satellite-image and wind data, the Darwin VAAC reported that during 29 July-4 August multiple ash plumes rose to altitudes of 4.3-4.9 km (14,000-16,000 ft) a.s.l. and drifted as far as 240 km in multiple directions. The Alert Level remained at 3 (on a scale of 1-4), and the public was reminded not to approach the crater within a 3-km radius.
Sources: Badan Nacional Penanggulangan Bencana (BNPB), Darwin Volcanic Ash Advisory Centre (VAAC)
Report for Suwanosejima
Based on JMA notices, satellite-image analyses, and pilot observations, the Tokyo VAAC reported that ash plumes from Suwanosejima rose to altitudes of 2.1-3 km (7,000-10,000 ft) a.s.l. and drifted E, SW, and W during 30-31 July and 4 August. On 2 August an ash plume rose to an altitude of 4 km (13,000 ft) a.s.l.
Source: Tokyo Volcanic Ash Advisory Center (VAAC)
Report for Dukono
Based on analyses of satellite imagery and wind data, the Darwin VAAC reported that during 29 July-4 August ash plumes from Dukono rose to altitudes of 2.1-3 km (7,000-10,000 ft) a.s.l. and drifted 55-155 km NW, N, NE, and ENE.
Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Report for Karangetang
Based on observations conducted at the Karangetang Volcano Observation Post in the village of Salili, PVMBG reported that white plumes rose as high as 250 m above the Main Crater and 25 m above Crater II during 22-29 July; foggy conditions occasionally prevented views. Incandescence from the lava dome was observed at night. Incandescent avalanches from the fronts of 150-m-long lava flows traveled as far as 2.5 km E down the Batuawang and Kahetang drainages. Seismicity was dominated by tremor and signals characteristic of avalanches, with rare volcanic earthquakes. The Alert Level remained at 3 (on a scale of 1-4); visitors and residents were warned not to approach Karangetang within a 4-km radius.
Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
Report for Karymsky
KVERT reported that moderate explosive activity at Karymsky continued during 24-31 July. Satellite images detected a daily thermal anomaly, as well as ash plumes that drifted 65 km E and NW during 25 and 27-30 July. Helicopter pilots observed explosions on 28 July; ash plumes rose to an altitude of 4 km (13,100 ft) a.s.l. and drifted N. The Aviation Color Code remained at Orange.
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Report for Kilauea
HVO reported that seismicity beneath Kilauea's summit, upper East Rift Zone, and Southwest Rift Zone was at background levels during 29 July-4 August. The lava lake continued to circulate and spatter in the Overlook vent. Webcams recorded multiple incandescent outgassing vents within Pu'u 'O'o; for 45 minutes on 31 July a lava flow effused from a vent on the E part of the crater floor. The June 27th NE-trending lava flow continued to be active with surface flows within 4-8 km NE of Pu'u 'O'o Crater.
Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
Report for Sheveluch
KVERT reported that during 24-31 July lava-dome extrusion onto Sheveluch’s N flank was accompanied by fumarolic activity, dome incandescence, and hot avalanches. Satellite images showed a daily thermal anomaly over the dome. The Aviation Color Code remained at Orange.
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Report for Shishaldin
AVO reported that seismicity at Shishaldin continued to be elevated over background levels 28 July-4 August indicating that low-level eruptive activity confined to the summit crater continued. Cloud cover sometimes prevented satellite and webcam observations; elevated surface temperatures were sometimes detected in satellite images. Satellite images detected a 24-km-long steam plume drifting SE on 28 July and vigorous steaming and plumes drifting SW on 31 July. A steam plume was recorded by the webcam on 2 August. 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 Sinabung
On 4 August BNPB reported that the eruption at Sinabung continued at a very high level. Lava was incandescent as far as 1.5 km SE and E down the flanks, and multiple avalanches were detected. Pyroclastic flows traveled at most 3 km ESE and SE, and ash plumes rose 2 km. The Alert Level remained at 4 (on a scale of 1-4), with an exclusion zone of 7 km from the volcano on the SE sector, and 6 km in the E sector. There were 3,152 families (11,114 people) displaced in 10 shelters, and an additional 2,053 families (6,179 people) in temporary shelters.
Source: Badan Nacional Penanggulangan Bencana (BNPB)
Report for Tungurahua
IG reported moderate seismic activity at Tungurahua during 29 July-4 August, characterized by long-period events and tremor. Cloud cover often prevented visual observations. On 31 July a steam-and-ash plume drifted W, producing ashfall in Pillate (8 km W), Choglontus (13 km WSW), Bilbao (8 km W), and El Manzano (8 km SW), Mocha (25 km W), and Tisaleo (29 km NW). A steam-and-ash plume drifted W on 1 August.
Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)