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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 24 July-30 July 2013
Name Location Eruption Start Date Report Status
Ambrym Vanuatu New
Karangetang Siau Island (Indonesia) 2018 Nov 25 New
Ketoi Kuril Islands (Russia) New
Popocatepetl Mexico 2005 Jan 9 New
Sheveluch Central Kamchatka (Russia) 1999 Aug 15 New
Tungurahua Ecuador New
Whakaari/White Island North Island (New Zealand) New
Aira Kyushu (Japan) 2017 Mar 25 Continuing
Chirinkotan Kuril Islands (Russia) Continuing
Chirpoi Kuril Islands (Russia) Continuing
Kilauea Hawaiian Islands (USA) 2020 Dec 20 Continuing
Kizimen Eastern Kamchatka (Russia) Continuing
Pacaya Guatemala 2015 Jun 7 ± 1 days Continuing
Reventador Ecuador 2008 Jul 27 Continuing
Tolbachik Central Kamchatka (Russia) Continuing
Veniaminof United States 2021 Feb 28 Continuing
Weekly Reports Archive

Since the Weekly Volcanic Activity Report began in November 2000, there have been 16,566 individual reports over 1,058 weeks (average of 16 per week) on 310 different volcanoes.

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


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 Ambrym
The Vanuatu Geohazards Observatory reported that activity at Ambrym slightly increased to a minor eruptive phase, and a seismic swarm was detected between 2400 and 0700 on 26 July. The Alert Level remained at 1 (on a scale of 0-4).
Source: Vanuatu Meteorology and Geo-Hazards Department (VMGD)
Report for Karangetang
Based on reports from the observation post in Salili, CVGHM stated on 26 July that the occurrence of rock avalanches descending Karangetang’s flanks decreased during 2013; the last one occurred on 7 July, and traveled 2 km down the Batuawang and Kahetang (E) drainages. Although fog often prevented visual observations, white plumes were sometimes seen rising up to 500 m from two craters. Incandescence from the lava dome was reflected in the plume at night. Seismicity fluctuated, but signals indicating avalanches declined. Based on the cessation of avalanches, visual observations, and decreasing seismicity, the Alert Level was lowered to 2 (on a scale of 1-4) on 26 July.
Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
Report for Ketoi
SVERT reported that on 25 July a thermal anomaly from Ketoi's Pallas Peak was observed in satellite imagery along with gas-and-steam emissions drifting 100 km NW. On 27 July gas-and-steam emissions possibly containing ash drifted 45 km SSE.
Source: Sakhalin Volcanic Eruption Response Team (SVERT)
Report for Popocatepetl
CENAPRED reported that on 23 July the Coordinación Nacional de Protección Civil (CNPC) of the Secretaría de Gobernación (SEGOB), CENAPRED, and a Scientific Advisory Committee lowered the Alert Level at Popocatépetl to Yellow, Phase Two. Access to the crater within a 12-km radius was prohibited.

During 24-30 July seismicity indicated continuing gas-and-steam emissions that sometimes contained ash; cloud cover often prevented visual confirmation. During 24-27 July often continuous plumes rose 200 m above the crater and drifted W, NW, and SW. Incandescence from the crater was observed most nights. Ash in the emissions was observed during 26-27 July. At 1237 and 1917 on 28 July, and 0733 on 29 July, ash plumes rose as high as 2 km and drifted W.
Source: Centro Nacional de Prevencion de Desastres (CENAPRED)
Report for Sheveluch
Based on visual observations and analyses of satellite data, KVERT reported that during 19-26 July a viscous lava flow effused on the N flank of Shiveluch's lava dome, accompanied by hot avalanches, incandescence, and fumarolic activity. Satellite images detected a daily thermal anomaly. Based on analyses of satellite images, the Tokyo VAAC reported a possible eruption on 27 July. Ash was detected in images the next day. The VAAC also noted that, according to the Kamchatka Branch of Geophysical Services (KBGS; Russian Academy of Sciences), ash plumes rose to altitudes of 6.1-6.4 km (20,000-21,000 ft) a.s.l. on 27 and 29 July. KVERT reported that at 1317 on 29 July an explosion was observed by a web camera. An ash cloud detected in satellite images rose to an altitude of 3.5 km (11,500 ft) a.s.l. and drifted 60 km ESE; the cloud was 15 km long and 7 km wide. The Aviation Color Code remained at Orange.
Sources: Kamchatkan Volcanic Eruption Response Team (KVERT), Tokyo Volcanic Ash Advisory Center (VAAC)
Report for Tungurahua
IG reported that activity at Tungurahua remained high during 24-30 July. Although cloud cover often prevented visual observations of the crater, plumes were observed almost daily. Roaring was also regularly reported. On 24 July an ash plume rose 5 km above the crater and drifted WNW, causing black ashfall in El Manzano (8 km SW), Choglontus (SW), Puela (8 km SW), Cahuají (8 km SW), and minor ashfall in Cevallos (23 km NW), Quero (20 km NW), and Mocha (25 km WNW). On 25 July ashfall was reported in El Manzano, Choglontus, and Cahuají. An explosion at 1835 generated an ash plume that rose 2 km and drifted W. The next day windows vibrated at the Tungurahua Observatory (OVT) in Guadalupe (14 km N). Minor amounts of ash fell in El Manzano, Choglontus, Puela, Mocha, and in the sectors of Guaranda (65 km WSW), Salinas, and Guanujo (65 km WSW). Overnight during 26-27 July Strombolian activity ejected blocks that rolled 300 m down the flanks. At 1947 a strong explosion vibrated windows at OVT and in El Manzano and Pillate (8 km W). An ash plume rose 2 km and drifted WSW; minor ashfall was reported in Bilbao (W), Quero, and Mocha. Later that day ash emissions rose 500 m and drifted SW.

Activity increased on 28 July; at 0626 a higher number of long-period earthquakes were detected, explosions became more frequent and larger, blocks were ejected, and ash emission rose from the crater. An explosion at 0723 generated a small pyroclastic flow that descended the N flank. Ash fell in Choglontus, El Manzano, Mocha, and Tisaleo (29 km NW). Activity remained high the next day; ash plumes rose 2 km and drifted WNW. During 28-29 July and ashfall was reported in Mocha, Quero, Tisaleo, Cevallos, and Pillate.
Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)
Report for Whakaari/White Island
GeoNet Data Centre reported that volcanic tremor levels at White Island increased overnight during 25-26 July; the increased seismicity and images of activity on web cameras prompted volcanologists to visit the volcano on 26 July. They noted audible jets of gas venting through the small lake, broader expanding “bubbles” of dark lake sediments, and debris ejected 20-30 m vertically. The Volcano Alert Level remained at 1 (on a scale of 0-5) and the Aviation Colour Code was increased to Yellow (on a four-color scale).
Source: GeoNet
Report for Aira
JMA reported that 10 explosions at Sakura-jima's Showa Crater were detected during 22-26 July, and ejected tephra as far as 1.3 km. Explosions at 1635 and 2333 on 22 July generated ash plumes that rose 3.2 and 3 km above the crater rim, respectively. Based on information from JMA, the Tokyo VAAC reported that during 24-30 July explosions generated plumes that rose to altitudes of 1.8-3.7 km (6,000-12,000 ft) a.s.l. and drifted E and SE. During 24-27 and 29 July pilots observed ash plumes that rose to altitudes of 2.7-5.5 km (9,000-18,000 ft) a.s.l. and drifted E and SE.
Sources: Japan Meteorological Agency (JMA), Tokyo Volcanic Ash Advisory Center (VAAC)
Report for Chirinkotan
Based on analysis of satellite images, SVERT reported that a thermal anomaly from Chirinkotan was observed on 22 July. Weak steam-and-gas emissions and a weak thermal anomaly were observed on 25 July. The Aviation Color Code remained at Yellow.
Source: Sakhalin Volcanic Eruption Response Team (SVERT)
Report for Chirpoi
SVERT reported that possible steam-and-gas emissions from Snow, a volcano of Chirpoi, were detected in satellite images on 23 July. The Aviation Color Code remained at Yellow.
Source: Sakhalin Volcanic Eruption Response Team (SVERT)
Report for Kilauea
During 24-30 July HVO reported that the circulating lava lake occasionally rose and fell in the deep pit within Kilauea's Halema'uma'u Crater. The plume from the vent continued to deposit variable amounts of ash, spatter, and Pele's hair onto nearby areas. The lake level receded during 25-26 July and was 75 km below the Halema'uma'u Crater floor on 26 July. The inner ledge, a long-time fixture within the vent, started collapsing at 2030 on 25 July; several pieces of the pit wall fell into the lake on both days. The lake level started to rise again and was 65 and 67 m below the crater floor on 28 and 29 July, respectively.

At Pu'u 'O'o Crater, glow emanated from three spatter cones and a small lava pond on the E part of the crater floor. The Kahauale’a 2 lava flow branches, fed by the NE spatter cone, were active as far NE as 3.2 km and as far NW as 2 km, and burned forest in two locations at the N edge of the 1983-1986 'a'a flows from Pu'u 'O'o. Peace Day activity, fed by lava tubes extending from Pu'u 'O'o, consisted of some breakout activity on the pali and coastal plain, and an ocean entry outside of the National Park boundary to the E.
Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
Report for Kizimen
KVERT reported that during 19-26 July moderate seismic activity continued at Kizimen. Video and satellite data showed that lava continued to extrude from the summit, producing incandescence, strong gas-and-steam activity, and hot avalanches on the W and E flanks. A thermal anomaly was detected in satellite images during 19-20 and 23 July; cloud cover obscured views on the other days. The Aviation Color Code remained at Orange.
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Report for Pacaya
In a special bulletin on 24 July, INSIVUMEH noted that the eruption at Pacaya had been changing during the previous few days, especially the seismic pattern. Seismic signals indicating explosions and ejections of material lasted up to seven minutes; the events were low frequency and long duration. The cone continued to grow and was 30 m high earlier in the week. By 24 July the cone was 4 m above the MacKenney crater rim. Seismicity again increased. On 25 July weak explosions and incandescence from the cone were observed at night. Rumbling was heard. On 29 July incandescence from the crater was observed for a few hours in the morning, and a plume rose at most 100 m and drifted S. An eruption on 30 July included a high-energy phase that lasted for four hours and incandescent material that was ejected 250 m above the cone. A diffuse ash plume drifted 2 km N, causing ashfall in areas downwind, and another ash plume drifted 5 km S. Activity then declined considerably; explosions were not observed and seismicity decreased, although signals indicating fluid movement continued to be detected.
Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Report for Reventador
IG reported that during 24-30 July seismic activity at Reventador remained high and was characterized by explosions, low-intensity emissions, and long-period earthquakes indicting fluid movement. Cloud cover mostly prevented visual observations. On 26 July an explosions generated a low-altitude ash plume that drifted W.
Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)
Report for Tolbachik
KVERT reported that the S fissure along the W side of Tolbachinsky Dol, a lava plateau on the SW side of Tolbachik, continued to produce very fluid lava flows during 19-26 July that traveled to the W, S, and E sides of the plateau. Cinder cones continued to grow along the S fissure and weak gas-and-steam plumes were observed. A thermal anomaly on the N part of Tolbachinsky Dol was visible daily in satellite imagery. The Aviation Color Code remained at Orange.
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Report for Veniaminof
AVO reported that the ongoing low-level eruption of Veniaminof, characterized by lava effusion and emissions of minor amounts of ash and steam, continued during 24-30 July, indicated by fluctuating volcanic tremor and occasional small explosions detected by the seismic network. On most days satellite images showed elevated surface temperatures at the cinder cone inside the caldera consistent with lava effusion. On 25 July a pilot reported an ash plume that rose 60-100 m above the cone and drifted almost 25 km S, and a "river of lava" flowing down from the cone. On 27 July a pilot observed an ash emission that rose 300-600 m and drifted NW. A water-rich plume likely containing minor amounts of ash was detected in satellite images drifting NW at an altitude of 4.5 km (15,000 ft) a.s.l. on 29 July. The Volcano Alert Level remained at Watch and the Aviation Color code remained at Orange.
Source: US Geological Survey Alaska Volcano Observatory (AVO)