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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 23 May-29 May 2018
Name Country Volcanic Province Eruption Start Date Report Status
Kilauea United States Hawaiian-Emperor Hotspot Volcano Group 2024 Sep 15 New
Klyuchevskoy Russia Eastern Kamchatka Volcanic Arc New
Merapi Indonesia Sunda Volcanic Arc 2020 Dec 31 New
Piton de la Fournaise France Reunion Hotspot Volcano Group New
Agung Indonesia Sunda Volcanic Arc Continuing
Aira Japan Ryukyu Volcanic Arc 2017 Mar 25 Continuing
Ambae Vanuatu Vanuatu Volcanic Arc Continuing
Dukono Indonesia Halmahera Volcanic Arc 1933 Aug 13 Continuing
Karymsky Russia Eastern Kamchatka Volcanic Arc 2024 Jun 20 Continuing
Langila Papua New Guinea Bismarck Volcanic Arc 2015 Oct 22 (?) Continuing
Mayon Philippines Eastern Philippine Volcanic Arc Continuing
Reventador Ecuador Northern Andean Volcanic Arc 2008 Jul 27 Continuing
Sabancaya Peru Central Andean Volcanic Arc 2016 Nov 6 Continuing
Sheveluch Russia Eastern Kamchatka Volcanic Arc 1999 Aug 15 Continuing
Turrialba Costa Rica Central America Volcanic Arc Continuing
All times are local unless otherwise stated.
Weekly Reports Archive

Since the Weekly Volcanic Activity Report began in November 2000, there have been 20,740 individual reports over 1,248 weeks (average of 17 per week) on 338 different volcanoes.

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Adams Cotopaxi Iliwerung Llaima Popocatepetl Sumisujima
Agung Cuicocha Inielika Lokon-Empung Purace Sundoro
Ahyi Cumbal Ioto Lonquimay Puyehue-Cordon Caulle Suoh
Aira Dabbahu Irazu Lopevi Rabaul Suretamatai
Akan Davidof Iwatesan Machin Raikoke Suwanosejima
Alaid Dempo Iya Makushin Ranakah Taal
Alu-Dalafilla Descabezado Grande Izu-Torishima Maly Semyachik Raoul Island Tair, Jebel at
Ambae Dieng Volcanic Complex Jackson Segment Manam Rasshua Takawangha
Ambang Dukono Kaba Manda Hararo Raung Talang
Ambrym East Epi Kadovar Marapi Redoubt Tambora
Anatahan Ebeko Kaitoku Seamount Maroa Reventador Tanaga
Aniakchak Ebulobo Kama'ehuakanaloa Martin Reykjanes Tandikat-Singgalang
Antillanca Volcanic Complex Edgecumbe Kambalny Masaya Rincon de la Vieja Tangkoko-Duasudara
Antuco Egon Kanaga Matthew Island Rinjani Tangkuban Parahu
Apoyeque Ekarma Kanlaon Maule, Laguna del Ritter Island Tara, Batu
Arenal Eldey Karangetang Mauna Loa Rotorua Ta'u
Asamayama Erebus Karkar Mayon Ruang Taupo
Askja Erta Ale Karthala McDonald Islands Ruapehu Telica
Asosan Etna Karymsky Melebingoy Ruby Tenerife
Atka Volcanic Complex Etorofu-Yakeyama [Grozny Group] Kasatochi Melimoyu Ruiz, Nevado del Tengger Caldera
Augustine Eyjafjallajokull Katla Merapi Sabancaya Three Sisters
Avachinsky Fagradalsfjall Katmai Midagahara Sakar Tinakula
Awu Fernandina Kavachi Misti, El Salak Tofua
Axial Seamount Fogo Kelimutu Miyakejima San Cristobal Tokachidake
Azul, Cerro Fonualei Kelud Momotombo San Miguel Tolbachik
Azumayama Fournaise, Piton de la Kerinci Monowai San Vicente Toliman
Bagana Fourpeaked Ketoi Montagu Island Sangay Tongariro
Balbi Fuego Kharimkotan Moyorodake [Medvezhia] Sangeang Api Trident
Bamus Fujisan Kick 'em Jenny Mutnovsky Santa Ana Tungurahua
Banda Api Fukutoku-Oka-no-Ba Kie Besi Myojinsho Santa Maria Turrialba
Bardarbunga Galeras Kikai Nabro Sao Jorge Ubinas
Barren Island Galunggung Kilauea Negra, Sierra Sarigan Ugashik-Peulik
Batur Gamalama Kirishimayama Negro, Cerro Sarychev Peak Ukinrek Maars
Bezymianny Gamkonora Kita-Ioto Nightingale Island Saunders Ulawun
Bogoslof Gareloi Kizimen Nishinoshima Savo Unnamed
Brava Gaua Klyuchevskoy Nisyros Semeru Unnamed
Bristol Island Gorely Kolokol Group Novarupta Semisopochnoi Veniaminof
Bulusan Great Sitkin Koryaksky NW Rota-1 Seulawah Agam Villarrica
Calbuco Grimsvotn Krakatau Nyamulagira Sheveluch Vulcano
Callaqui Guagua Pichincha Krummel-Garbuna-Welcker Nyiragongo Shishaldin West Mata
Cameroon Guallatiri Krysuvik-Trolladyngja Ofu-Olosega Simbo Westdahl
Campi Flegrei Guntur Kuchinoerabujima Okataina Sinabung Whakaari/White Island
Campi Flegrei del Mar di Sicilia Hachijojima Kurikomayama Okmok Sinarka Witori
Cayambe Hakoneyama Kusatsu-Shiranesan Ontakesan Siple Wolf
Chachadake [Tiatia] Heard Kverkfjoll Oraefajokull Sirung Wrangell
Chaiten Hekla La Palma Osorno Slamet Yakedake
Chiginagak Helgrindur Lamington Pacaya Snaefellsjokull Yasur
Chikurachki Hierro Lamongan Pagan Soputan Yellowstone
Chiles-Cerro Negro Hokkaido-Komagatake Langila Palena Volcanic Group Sorikmarapi Yufu-Tsurumi
Chillan, Nevados de Home Reef Lanin Paluweh Sotara Zaozan [Zaosan]
Chirinkotan Hood Lascar Panarea Soufriere Hills Zavodovski
Chirpoi Huaynaputina Late Papandayan Soufriere St. Vincent Zhupanovsky
Ciremai Hudson, Cerro Lateiki Pavlof South Sarigan Seamount Zubair Group
Cleveland Huila, Nevado del Lengai, Ol Doinyo Pelee Spurr
Colima Hunga Tonga-Hunga Ha'apai Leroboleng Peuet Sague St. Helens
Colo Ibu Lewotobi Pinatubo Stromboli
Concepcion Ijen Lewotolok Planchon-Peteroa Sulu Range
Copahue Iliamna Little Sitkin Poas Sumbing
 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 Kilauea
HVO reported that the eruption at Kilauea’s Lower East Rift Zone (LERZ) and at Overlook Crater within Halema`uma`u Crater continued during 23-29 May. Lava fountaining and spatter was concentrated in the middle portion of the fissure system, feeding lava flows that spread through Leilani Estates and Lanipuna Gardens subdivisions, and also traveled to the ocean.

Earthquakes beneath the summit and ash emissions from Overlook Crater continued as the summit area subsided and adjusted to the withdrawal of magma. Ash emissions were small and frequent, punctuated by larger plumes. The Overlook crater vent continued to widen to the W, and by 25 May the vent area was about 36 hectares. At 1244 on 25 May a M 4 earthquake was located in the summit region. That same day a new pit opened on the N part of Halema`uma`u Crater floor. Three explosions (at 0042, 0144, and 0500) on 26 May generated ash plumes that rose 3-3.3 km (10,000-10,800 ft) a.s.l. A small explosion at 0156 on 29 May sent an ash plume vertically to 4.6 km (15,000 ft) a.s.l. and drifted slightly NW. The explosion was felt by residents in Volcano, and ejected incandescent blocks within Halema`uma`u Crater. On 28 May a M 4.1 earthquake occurred at 1739 along the Koa'e fault zone, S of the caldera.

Lava fountains from Fissure 22 continued to form a channelized lava flow that entered the ocean NE of MacKenzie State Park, causing explosions and generating a plume of hazardous laze (lava haze, a mixture of condensed acidic steam, hydrochloric acid gas, and tiny shards of volcanic glass). On 23 May relatively tall lava fountains at fissures 6 and 13 fed another channelized flow that created a second ocean entry. Observers noted that a perched lava pond/channel was 11 m above ground level, and that methane was seen overnight that burned blue in road cracks. On 24 May lava was entering the ocean at three points between Pohoiki Bay and MacKenzie State Park, though by the next day only two were active.

Overnight during 25-26 May vigorous spatter was observed from a cone on Fissure 8, and multiple booming gas emissions occurred at Fissure 17. By the morning of 26 May an estimated 9.6 square kilometers had been covered by new lava. Fissures 7 and 21 fed a perched lava pond and sent flows NE; the lava-flow fronts became ‘a’a. A perched pond on the W side of Fissure 7 was breached, sending short flows W. Later that day the flows turned S, and by dusk were cascading into Pawaii crater, adjacent to the W margin of the Fissure 6 flow that fed one of the ocean entries. Lava from Fissure 21 flowed onto Puna Geothermal Venture (PGV) property.

During 26-27 May activity at Fissure 7 increased; lava from fountains 45-60 m tall built a large, 30-m-high spatter rampart. Large cracks were observed overnight on Kupono St., near Fissure 9. Three vents active at Fissure 8 spattered and flamed, and doubled in size in one day. On 27 May lava flows from fissures 7 and 8 advanced NE on PGV property; at about 1900 a flow broke out in this area and advanced rapidly to the N and W, through the E portion of Leilani Estates, prompting several residents to evacuate. Three minor ocean entries were again active. Fissure 24 opened in Leilani Estates.

On 28 May the vents that fed the ocean entries stopped erupting, leading to only residual lava in the channel to occasionally enter the ocean. During 28-29 May fountains, lava flows, and spattering from multiple fissures persisted. Pele's hair from vigorous fountaining (60 m high) at Fissure 8 drifted downwind, with some strands falling in Pahoa. According to a news article, the LERZ eruption had destroyed at least 94 structures, including 53 homes, by 29 May. The flows also cut off road access to PGV, which had been evacuated.
Sources: US Geological Survey Hawaiian Volcano Observatory (HVO), KIII-TV
Report for Klyuchevskoy
KVERT reported that a thermal anomaly over Klyuchevskoy was identified in satellite images during 19-20 and 24 May. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Report for Merapi
PVMBG reported that a two-minute-long phreatic eruption at Merapi which began at 1349 on 23 May was heard from the Babadan observation post. A plume was not visible due to inclement weather, though minor ashfall was reported in Ngepos post. On 24 May an event at 0256 generated an ash plume that rose 6 km above the crater rim and drifted W. Roaring was heard from all of the Merapi observation posts. A two-minute-long event at 1048 produced an ash plume that rose 1.5 km and drifted W. The Alert Level remained at 2 (on a scale of 1-4), and PVMBG noted that all people within 3 km of the summit should be evacuated.
Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
Report for Piton de la Fournaise
OVPF reported that the eruption at Piton de la Fournaise which began on 27 April from fissures at Rivals Crater continued through 29 May. Tremor levels continued to decrease slightly, though were mostly stable at low levels. Observations on 24 May indicated flowing lava was mostly confined to tubes, though a small area of incandescence was visible at the main crater.
Source: Observatoire Volcanologique du Piton de la Fournaise (OVPF)
Report for Agung
PVMBG reported that although there were some periods of foggy conditions during 23-29 May, white plumes were occasionally observed rising as high as 400 m above Agung’s crater rim. At 0539 on 29 May an event generated an ash plume that rose 500 m above the crater rim and drifted SW. The Alert Level remained at 3 (on a scale of 1-4) and the exclusion zone continued at a 4-km radius.
Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
Report for Aira
JMA reported that there were 21 events and 19 explosions at Minamidake crater (at Aira Caldera’s Sakurajima volcano) during 21-28 May. Tephra was ejected as far as 1.3 km from the crater, and ash plumes rose as high as 3.2 km above the crater rim. The Alert Level remained at 3 (on a 5-level scale).
Source: Japan Meteorological Agency (JMA)
Report for Ambae
On 18 May a news article noted that the eruption from a cone in Ambae’s Lake Voui continued with minor activity at the vent. The article noted that widespread ashfall had significantly impacted food and water supplies, shelter, and the health of island residents. The Alert Level remained at 3 (on a scale of 0-5), and the report reminded residents to stay at least 3 km away from the active crater.
Source: Daily Post
Report for Dukono
Based on analyses of satellite imagery, wind model data, and notices from PVMBG, the Darwin VAAC reported that during 23-29 May ash plumes from Dukono rose to altitudes of 1.8-2.1 km (6,000-7,000 ft) a.s.l. and drifted W, WNW, and NW. Ash plumes drifted as far as 225 km NW on 28 May.
Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Report for Karymsky
KVERT reported that during 19-20 May a thermal anomaly over Karymsky was identified in satellite images. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Report for Langila
Based on analyses of satellite imagery and model data, the Darwin VAAC reported that during 23 and 26-28 May ash plumes from Langila rose to altitudes of 2.4-3 km (8,000-10,000 ft) a.s.l. and drifted WSW, W, and NW.
Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Report for Mayon
PHIVOLCS reported that during 23-29 May white steam plumes from Mayon drifted WNW, WSW, and SW, sometimes rising 250-300 m above the crater rim. Crater incandescence was visible each night. The Alert Level remained at 2 (on a 0-5 scale) and PHIVOLCS reminded residents to stay away from the 6-km-radius Permanent Danger Zone and the 7-km Extended Danger Zone on the SSW and ENE flanks.
Source: Philippine Institute of Volcanology and Seismology (PHIVOLCS)
Report for Reventador
During 23-28 May IG reported a high level of seismic activity including explosions, long-period earthquakes, harmonic tremor, and signals indicating emissions at Reventador. Steam, gas, and ash plumes rose 1.5 km above the crater rim and drifted NW on 23 May, and a plume of gas, water vapor, and ash rose 300 m on 26 May; cloudy weather prevented views of emissions on most days. A lava flow had advanced to 900 m on the NE flank. On 27 May incandescent blocks were observed rolling as far as 800 m down the flanks in multiple directions. An ash plume rose 3 km above the crater rim and quickly drifted W, causing ashfall in Papallacta (62 km SW), San Antonio de Pichincha (90 km W), Tabacundo (63 km WNW), Cayambe (57 km WNW), Puellaro (85 km WNW), and Puembo (80 km W).
Source: Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN)
Report for Sabancaya
Observatorio Vulcanológico del Sur del IGP (OVS-IGP) and Observatorio Vulcanológico del INGEMMET (OVI) reported that explosive activity at Sabancaya was comparable to the previous week; explosions averaged 35 per day during 21-27 May. Seismicity was dominated by long-period events and signals indicating emissions. Gas-and-ash plumes rose as high as 3.3 km above the crater rim and drifted 30 km NE, E, and SE. The MIROVA system detected nine thermal anomalies, and on 24 May the sulfur dioxide gas flux was high at 3,950 tons/day. The report noted that the public should not approach the crater within a 12-km radius.
Sources: Instituto Geológico Minero y Metalúrgico (INGEMMET), Instituto Geofísico del Perú (IGP)
Report for Sheveluch
KVERT reported that a weak thermal anomaly over Sheveluch was identified in satellite images on 19-20 and 23-24 May. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Report for Turrialba
OVSICORI-UNA reported that an event at Turrialba at 0930 on 28 May generated a plume that rose 300 m above the crater rim and drifted SE.
Source: Observatorio Vulcanologico y Sismologico de Costa Rica-Universidad Nacional (OVSICORI-UNA)