Logo link to homepage

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 25 July-31 July 2007
Name Location Eruption Start Date Report Status
Cleveland Chuginadak Island (USA) New
Gamkonora Halmahera (Indonesia) New
Kilauea Hawaiian Islands (USA) 2021 Sep 29 New
Ol Doinyo Lengai Tanzania 2017 Apr 9 New
Raung Eastern Java (Indonesia) New
Karymsky Eastern Kamchatka (Russia) 2020 Apr 1 Continuing
Sangay Ecuador 2019 Mar 26 Continuing
Sheveluch Central Kamchatka (Russia) 1999 Aug 15 Continuing
Soufriere Hills Montserrat Continuing
St. Helens United States Continuing
Suwanosejima Ryukyu Islands (Japan) 2004 Oct 23 Continuing
Tungurahua Ecuador 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 17,140 individual reports over 1,086 weeks (average of 16 per week) on 316 different volcanoes.

Search by Date



Use the dropdowns to choose the year and week for archived Weekly Reports.

Use the dropdowns to choose the year and week for archived Weekly Reports.          



Search by Volcano



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



Download Smithsonian / USGS Weekly Volcanic Activity Report Network CAP Feed

The CAP (Common Alerting Protocol) feeds are XML files specifically formatted for disaster management. They are similar in content to the RSS feed, but contain no active links.



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 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 Cleveland
A thermal anomaly in the crater of Cleveland was visible on satellite imagery during 25-26 July. The Volcanic Alert Level remained at Watch and the Aviation Color Code remained at Orange through at least 30 July. On the 27th AVO noted that low-level eruptive activity continued. Three small SO2 clouds produced by small explosions on 20 July were detected in OMI satellite data provided by the University of Maryland Baltimore County. No further explosive activity had been detected by the OMI sensor since that time. AVO is unable to track local earthquake activity related to volcanic unrest.
Sources: US Geological Survey Alaska Volcano Observatory (AVO), OMI Sulfur Dioxide Group
Report for Gamkonora
CVGHM lowered the Alert Level for Gamkonora from 3 to 2 (on a scale of 1-4) on 24 July based on visual observations and a decrease in seismicity. That followed a sharp drop in seismicity during 8-23 July, a decline both in terms of the number of events and their energy. Later, during 16-23 July, when breaks in inclement weather took place, observers saw white plumes rising to altitudes of 5.6 km (18,400 ft) a.s.l. Available CVGHM reports issued through the 26 July did not disclose more recent events.
Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
Report for Kilauea
An important new eruption initiated at Kilauea very early on 21 July. It occurred along the E rift zone from fissures trending ENE for several kilometers from Pu'u O'o. The fissures caused drainage of both the West Gap lava lake and the Puka Nui pit. These and following events have come to be called the 21 July eruption and an associated fissure system by the same name.

As of 25 July, the 21 July eruption included instability at Pu'u 'O'o, fissuring along an NE-trending zone stretching a bit over 2 km in length, and lava flows over an area of a little over 1 km2.

A noteworthy feature of this eruption during the week 25-31 July was the formation of a series of perched ponds of lava. These formed as the edges of pools of lava hardened to create confining walls. These walls enable the pond's surface to be much higher--in some cases as much as 5 m (15 feet) higher than the surrounding land--like a volcanic above-ground swimming pool. During the 21 July eruption the walls of these perched ponds breached repeatedly, allowing lava to suddenly flood surrounding terrain. For example, at least three perched lava ponds breached by the 25th, each breakage spawning radially directed lava flows. Other small lava flows also emerged from fissures during the week as well.

The behavior of the perched ponds is difficult to judge and accordingly, around the start of this week the area was closed to the public. The eruption resided completely within the Kahauale'a Natural Area Reserve (just NE of the Hawai'i Volcanoes National Park).

On the morning of the 26th, an M 3.2 earthquake occurred on the lower E rift zone, beneath Pu'ulena crater, at a depth of 3 km (2 miles). Lava ponds again formed in the area surrounding the fissures but views of the process were hampered by foul weather. The HVO update for 31 July noted two prominent lava ponds then. In addition, one of the fissures fed an 'a'a flow advancing to the NE around the N side of Kupaianaha.
Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
Report for Ol Doinyo Lengai
Ol Doinyo Lengai is frequently the scene of fluid but very small volume lava flows in its summit crater, including a few that passed over the crater rim and begun the long descent down the mountain. As noted here last week, news reports had indicated that products of the volcano's 19-July eruption had entered inhabited areas. Subsequent investigations have cast doubt on those earlier claims.

Discussions this week by volcanologist Gerald Ernst with contacts in the region revealed that neither aviators, guides, scientists, nor locals had seen dramatic eruptive events at the mountain. The summit crater was intact, but eruptions were confined to the summit area. What was interpreted from a distance as a modest landslide in the crater may have sent out a dust cloud. That cloud could have been confused with ash from a large flank eruption.

To help shed light on the situation, Greg Vaughan of the Jet Propulsion Labs had a preliminary look at some ASTER satellite data of the volcano and concluded that in mid-June through late July the summit crater was likely to have continued to emit lava. The 20 July thermal emissions appeared no larger than those on 18 June. Those from 15 April appeared weaker. The images supported summit lava eruptions but failed to document any lava that had spilled over the crater rim.
Sources: Gerald Ernst, Centre for Environmental & Geophysical Flows, Department of Earth Sciences, University of Bristol, Greg Vaughan, Jet Propulsion Laboratory
Report for Raung
Based on a pilot report, the Darwin VAAC reported that an ash plume possibly from Raung rose to an altitude of 1.5 km (5,000 ft) a.s.l. Ash was not visible on satellite imagery.
Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Report for Karymsky
A KVERT report issued for Karymsky on 27 July stated the following, "The eruption of the volcano continues. Ash explosions up to 6 km (or 19,700 ft.) a.s.l. are possible at any time. The activity of the volcano could affect low-flying aircraft in the vicinity of the volcano."

Based on a report from unstated source and posted by the Tokyo VAAC, on 28 July ash plumes rose to estimated altitudes of ~6 km (20,000 ft) a.s.l., but the plume could not be identified in satellite analysis. The Level of Concern Color Code remained at Orange.
Sources: Kamchatkan Volcanic Eruption Response Team (KVERT), Tokyo Volcanic Ash Advisory Center (VAAC)
Report for Sangay
Based on pilot observations, the Washington VAAC reported that an ash plume from Sangay rose to an altitude of 6.7-8.2 km (22,000 to 27,000 ft) a.s.l. on 28 July. Ash was not detected on satellite imagery but a weak hotspot could be seen.
Source: Washington Volcanic Ash Advisory Center (VAAC)
Report for Sheveluch
KVERT reports noted that seismic activity at Shiveluch continued above background levels during 20-27 July. Based on seismic interpretation, during this interval ash plumes rose to an altitude of 6 km (19,700 ft) a.s.l. Gas-and-steam plumes with some ash rose to altitudes of 3.0-4.5 km (9,800-14,800 ft) a.s.l. during 20-24 July. Based on satellite imagery, gas-and-steam plumes drifted S on 22 July and a large thermal anomaly was detected in the crater during 20-27 July. Through at least 27 July, the Level of Concern Color Code remained at Orange.
Sources: Kamchatkan Volcanic Eruption Response Team (KVERT), Tokyo Volcanic Ash Advisory Center (VAAC)
Report for Soufriere Hills
MVO reported that based on visual observations, the lava dome at Soufrière Hills changed very little during 25-26 July. 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 25-31 July lava-dome growth at Mount St. Helens continued. Seismicity persisted at low levels.
Source: US Geological Survey Cascades Volcano Observatory (CVO)
Report for Suwanosejima
Based on information from JMA and a pilot report, the Tokyo VAAC reported that an ash plume from Suwanose-jima rose to an altitude of 1.5 km (5,000 ft) a.s.l. and drifted SW on 26 July. Ash was not visible on satellite imagery.
Source: Tokyo Volcanic Ash Advisory Center (VAAC)
Report for Tungurahua
As noted by the IG in their daily reports covering 25-31 July, Tungurahua emitted a substantial number of small ash-bearing explosions and several unusually large ones as well. Based on ground observer estimates, many plumes during the reporting interval rose to 2-3 km above the crater rim (up to ~1 mile above the crater) and dropped ash on towns located on the volcano's flanks.

On the 26th, the IG reported one of the larger explosions, the biggest since March 2007 (its seismic signal yielded a reduced displacement of 9.2 cm2). Associated ashfalls affected some parts of the volcano. The explosion took place at night and the plume height was not estimated.

On the 30th IG observers witnessed another strong explosion that generated a heavily ash-laden plume. The dense portion of the plume rose 400 m above the crater rim. A similar plume had not been seen since 16 August 2006. The associated column of less dense material rose to 3 km and visible portions of dense material appeared as a curtain of ash deposited to the W. Some blocks associated with the outburst rolled up to 0.5 km below the crater's rim. Visibility hampered further observations that day but the many emission noises included the hammering of bouncing blocks.

Tungurahua's 25-31 July activity spurred numerous VAAC reports, but satellite analysts generally had great difficulty with cloudy conditions and few if any plumes were clearly detected.
Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)
Report for Ubinas
Based on a Significant Meteorological Information (SIGMET) advisory, the Buenos Aires VAAC reported that ash plumes from Ubinas rose to an altitude of 5.8 km (19,000 ft) a.s.l. on 23 and 25 July. The plumes drifted SE and S, respectively. Ash was not identified on satellite imagery. On 24 July, a diffuse plume was visible on satellite imagery at an altitude of 6.1 km (20,000 ft) a.s.l.
Source: Buenos Aires Volcanic Ash Advisory Center (VAAC)