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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 27 May-2 June 2009
Name Country Volcanic Province Eruption Start Date Report Status
Karangetang Indonesia Sangihe Volcanic Arc New
Kie Besi Indonesia Halmahera Volcanic Arc New
Slamet Indonesia Sunda Volcanic Arc New
Aira Japan Ryukyu Volcanic Arc 2017 Mar 25 Continuing
Bagana Papua New Guinea Solomon Volcanic Arc 2000 Feb 28 (in or before) Continuing
Batu Tara Indonesia Sunda Volcanic Arc Continuing
Chaiten Chile Andean Southern Volcanic Arc Continuing
Dukono Indonesia Halmahera Volcanic Arc 1933 Aug 13 Continuing
Etna Italy Sicily Volcanic Province Continuing
Kilauea United States Hawaiian-Emperor Hotspot Volcano Group Continuing
Llaima Chile Andean Southern Volcanic Arc Continuing
Nevado del Huila Colombia Andean Northern Volcanic Arc Continuing
Popocatepetl Mexico Trans-Mexican Volcanic Belt 2005 Jan 9 Continuing
Rabaul Papua New Guinea Bismarck Volcanic Arc Continuing
Redoubt United States Alaska Peninsula Volcanic Arc Continuing
Sheveluch Russia Eastern Kamchatka Volcanic Arc 1999 Aug 15 Continuing
Soufriere Hills United Kingdom Lesser Antilles Volcanic Arc Continuing
Tungurahua Ecuador Andean Northern Volcanic Arc Continuing
Ubinas Peru Andean Central Volcanic Arc 2024 May 6 Continuing
All times are local unless otherwise stated.
Weekly Reports Archive

Since the Weekly Volcanic Activity Report began in November 2000, there have been 20,322 individual reports over 1,229 weeks (average of 17 per week) on 336 different volcanoes.

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Agung Cotopaxi Iliamna Little Sitkin Planchon-Peteroa Stromboli
Ahyi Cuicocha Iliwerung Llaima Poas Sulu Range
Aira Cumbal Inielika Lokon-Empung Popocatepetl Sumbing
Akan Dabbahu Ioto Lonquimay Purace Sumisujima
Alaid Davidof Irazu Lopevi Puyehue-Cordon Caulle Sundoro
Alu-Dalafilla Dempo Iya Machin Rabaul Suoh
Ambae Descabezado Grande Izu-Torishima Makushin Raikoke Suretamatai
Ambang Dieng Volcanic Complex Jackson Segment Maly Semyachik Ranakah Suwanosejima
Ambrym Dukono Kaba Manam Raoul Island Taal
Anatahan East Epi Kadovar Manda Hararo Rasshua Tair, Jebel at
Aniakchak Ebeko Kaitoku Seamount Marapi Raung Takawangha
Antillanca Volcanic Complex Ebulobo Kama'ehuakanaloa Maroa Redoubt Talang
Antuco Edgecumbe Kambalny Martin Reventador Tambora
Apoyeque Egon Kanaga Masaya Reykjanes Tanaga
Arenal Ekarma Kanlaon Matthew Island Rincon de la Vieja Tandikat-Singgalang
Asamayama Eldey Karangetang Maule, Laguna del Rinjani Tangkoko-Duasudara
Askja Erebus Karkar Mauna Loa Ritter Island Tangkuban Parahu
Asosan Erta Ale Karthala Mayon Rotorua Tara, Batu
Atka Volcanic Complex Etna Karymsky McDonald Islands Ruang Ta'u
Augustine Etorofu-Yakeyama [Grozny Group] Kasatochi Melebingoy Ruapehu Taupo
Avachinsky Eyjafjallajokull Katla Melimoyu Ruby Telica
Awu Fagradalsfjall Katmai Merapi Ruiz, Nevado del Tenerife
Axial Seamount Fernandina Kavachi Midagahara Sabancaya Tengger Caldera
Azul, Cerro Fogo Kelimutu Misti, El Sakar Three Sisters
Azumayama Fonualei Kelud Miyakejima Salak Tinakula
Bagana Fournaise, Piton de la Kerinci Momotombo San Cristobal Tofua
Balbi Fourpeaked Ketoi Monowai San Miguel Tokachidake
Bamus Fuego Kharimkotan Montagu Island San Vicente Tolbachik
Banda Api Fujisan Kick 'em Jenny Moyorodake [Medvezhia] Sangay Toliman
Bardarbunga Fukutoku-Oka-no-Ba Kie Besi Mutnovsky Sangeang Api Tongariro
Barren Island Galeras Kikai Myojinsho Santa Ana Trident
Batur Galunggung Kilauea Nabro Santa Maria Tungurahua
Bezymianny Gamalama Kirishimayama Negra, Sierra Sao Jorge Turrialba
Bogoslof Gamkonora Kita-Ioto Negro, Cerro Sarigan Ubinas
Brava Gareloi Kizimen Nightingale Island Sarychev Peak Ugashik-Peulik
Bristol Island Gaua Klyuchevskoy Nishinoshima Saunders Ukinrek Maars
Bulusan Gorely Kolokol Group Nisyros Savo Ulawun
Calbuco Great Sitkin Koryaksky Novarupta Semeru Unnamed
Callaqui Grimsvotn Krakatau NW Rota-1 Semisopochnoi Unnamed
Cameroon Guagua Pichincha Krummel-Garbuna-Welcker Nyamulagira Seulawah Agam Veniaminof
Campi Flegrei Guallatiri Krysuvik-Trolladyngja Nyiragongo Sheveluch Villarrica
Campi Flegrei del Mar di Sicilia Guntur Kuchinoerabujima Ofu-Olosega Shishaldin Vulcano
Cayambe Hachijojima Kurikomayama Okataina Simbo West Mata
Chachadake [Tiatia] Hakoneyama Kusatsu-Shiranesan Okmok Sinabung Westdahl
Chaiten Heard Kverkfjoll Ontakesan Sinarka Whakaari/White Island
Chiginagak Hekla La Palma Oraefajokull Siple Witori
Chikurachki Helgrindur Lamington Osorno Sirung Wolf
Chiles-Cerro Negro Hierro Lamongan Pacaya Slamet Wrangell
Chillan, Nevados de Hokkaido-Komagatake Langila Pagan Snaefellsjokull Yakedake
Chirinkotan Home Reef Lanin Palena Volcanic Group Soputan Yasur
Chirpoi Hood Lascar Paluweh Sorikmarapi Yellowstone
Ciremai Huaynaputina Late Panarea Sotara Yufu-Tsurumi
Cleveland Hudson, Cerro Lateiki Papandayan Soufriere Hills Zaozan [Zaosan]
Colima Huila, Nevado del Lengai, Ol Doinyo Pavlof Soufriere St. Vincent Zavodovski
Colo Hunga Tonga-Hunga Ha'apai Leroboleng Pelee South Sarigan Seamount Zhupanovsky
Concepcion Ibu Lewotobi Peuet Sague Spurr Zubair Group
Copahue Ijen Lewotolok Pinatubo St. Helens
 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 Karangetang
CVGHM reported that seismicity from Karangetang increased during 30-31 May and tremor was detected. On 30 May, diffuse white plumes rose 10-50 m high and incandescence was seen at the crater. On 31 May, white emissions from Utama Crater in the N part of the summit region rose 100 m. Incandescent material traveled as far as 2.3 km, mostly down the S flank. Ash plumes that rose 25-700 m were accompanied by thunderous sounds. The Alert Level was raised to 4, the highest level on a scale of 1-4. People were advised not to go within a 3-km-radius of the active area. According to a news article, over 350 people evacuated the area.
Sources: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM), People's Daily Online (China)
Report for Kie Besi
CVGHM reported that during 28 May-2 June seismicity from Makian increased, particularly the occurrence of tremor. Little, if any, increases in emissions were seen. The Alert level was raised to 2 (on a scale of 1-4).
Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
Report for Slamet
Based on ground information from CVGHM, the Darwin VAAC reported that on 27 May an ash plume from Slamet rose to an altitude of 4.3 km (14,000 ft) a.s.l. Analysis of satellite imagery indicated that a possible plume rose to an altitude of 6.1 km (20,000 ft) a.s.l., but ash was not conclusively detected.
Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Report for Aira
Based on information from JMA, the Tokyo VAAC reported that on 30 May an explosion from Sakura-jima produced a plume that rose to an altitude of 4.6 km (15,000 ft) a.s.l. and drifted SE. On 31 May, an ash plume rose to an altitude of 3 km (10,000 ft) a.s.l. The next day, eruptions produced plumes that rose to altitudes of 2.1-3.4 km (7,000-11,000 ft) a.s.l. Some plumes drifted S.
Source: Tokyo Volcanic Ash Advisory Center (VAAC)
Report for Bagana
Based on analysis of satellite imagery, the Darwin VAAC reported that on 2 June an ash plume from Bagana rose to an altitude of 2.4 km (8,000 ft) a.s.l. and drifted 75 km W.
Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Report for Batu Tara
Based on analysis of satellite imagery, the Darwin VAAC reported that during 27 May-2 June ash plumes from Batu Tara rose to an altitude of 2.4 km (8,000 ft) a.s.l. and drifted 25-75 km NW, W, and SW. A thermal anomaly was also identified on satellite imagery on 29 May.
Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Report for Chaiten
Based on web camera views, SERNAGEOMIN reported that during 20-27 May gas-and-ash plumes rose 1.5 km from Chaitén's growing Domo Nuevo 1 and Domo Nuevo 2 lava-dome complex. Collapses originating from unstable slopes generated block-and-ash flows that were sometimes seen from Chaitén town, 10 km SW. Seismicity remained elevated; the hypocenters of the large hybrid earthquakes were located under the W part of the complex at depths of 5-9 km. The Alert Level remained at Red. Based on web camera views, the Buenos Aires VAAC reported that during 28-29 May and 1-2 June ash plumes rose to altitudes of 1.8-2.4 km (6,000-8,000 ft) a.s.l. Thermal anomalies were also seen in satellite imagery on all three days.
Sources: Buenos Aires Volcanic Ash Advisory Center (VAAC), Servicio Nacional de Geología y Minería (SERNAGEOMIN)
Report for Dukono
Based on analysis of satellite imagery, the Darwin VAAC reported that during 27-28 May ash plumes from Dukono rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted 55-110 km NE.
Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Report for Etna
INGV-CT reported that during 25-31 May the NW-SE-trending fissure E of the Etna summit craters continued (since 13 May 2008) to produce active lava flows to the N of the SE end of the fissure, along the W wall of the Valle del Bove. At least three lava flows were active. Elsewhere on the volcano, activity was restricted to degassing from the Northeast Crater, from the NW and SE Bocca Nuova vents, from the E flank of the Southeast Crater, and along summit fumarolic fields. The activity was observed directly and by utilizing surveillance cameras in Milo (about 11 km ESE).
Source: Sezione di Catania - Osservatorio Etneo (INGV)
Report for Kilauea
During 27 May-2 June, HVO reported that lava flowed SE from underneath Kilauea's Thanksgiving Eve Breakout (TEB) and rootless shield complex through a lava tube system, reaching the Waikupanaha ocean entry. The Kupapa'u ocean entry was active until 31 May. On 30 May, a thermal anomaly on the upper TEB flow field was detected on satellite imagery. Pilot reports and satellite imagery analysis on 2 June confirmed active surface lava flows in this area. A small channelized 'a'a lava flow had stagnated above the top of the pali.

The vent in Halema'uma'u crater continued to produce a predominantly white plume, occasionally tinged brown, that drifted mainly SW. Small amounts of ash-sized tephra, including Pele's hair, Pele's tears, and fresh spatter, were retrieved from collection bins placed near the plume during the reporting period. A molten lava pool near the base of the cavity, deep below the floor of the vent, produced incandescence of variable intensity. Sounds resembling rushing gas were sometimes heard in the vicinity of the crater.
Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
Report for Llaima
SERNAGEOMIN reported that scientists aboard an overflight of Llaima on 1 June observed a 2-square-kilometer area with an elevated temperature on the E flank. Several small areas emitted gas and a small cone was forming about 800 m below the crater. They also saw an E-W trending fissure 200 m from the rim of the main crater that was about 300 m long. Brown ash and steam plumes were emitted from different areas of the fissure. The irregularly-shaped summit crater had a few weak fumaroles. The Volcano Alert Level remained at Yellow.
Source: Servicio Nacional de Geología y Minería (SERNAGEOMIN)
Report for Nevado del Huila
INGEOMINAS reported a seismic swarm at Nevado del Huila on 28 May that included M 4 and M 4.8 earthquakes felt by local residents. On 31 May, an episode of tremor was associated with an ash emission seen on a web camera. Another pulse of tremor was detected on 2 June. The Alert Level remained at III (Yellow; "changes in the behavior of volcanic activity").
Source: Servicio Geológico Colombiano (SGC)
Report for Popocatepetl
CENAPRED reported that emissions of steam and gas from Popocatépetl were visible during 27 May-2 June; the plumes contained slight amounts of ash during 27-29 May.
Source: Centro Nacional de Prevencion de Desastres (CENAPRED)
Report for Rabaul
RVO reported that during 21-28 May white and occasionally blue plumes from Rabaul caldera's Tavurvur cone rose 1 km above the crater. Incandescence from the summit crater was seen at night.
Source: Rabaul Volcano Observatory (RVO)
Report for Redoubt
AVO reported that during 27 May-2 June seismicity from Redoubt remained low, but above background levels; small discrete earthquakes and rockfall signals in the summit region were recorded. Growth of the lava dome in the summit crater continued. Cloudy conditions obscured satellite and web camera views. AVO warned that the unstable lava dome could fail with little or no warning, leading to significant ash emissions and possible lahars in the Drift River valley. The Volcanic Alert Level remained at Watch and the Aviation Color Code remained at Orange.
Source: US Geological Survey Alaska Volcano Observatory (AVO)
Report for Sheveluch
KVERT reported that during 22-29 May seismic activity from Shiveluch was above background levels. Steam-and-gas emissions were seen during 21-23 May. Based on video camera views, gas-and-steam plumes containing a small amount of ash rose to an altitude of 4 km (13,100 ft) a.s.l. on 22 May. Analysis of satellite imagery revealed a daily thermal anomaly over the lava dome. The Level of Concern Color Code remained at Orange.
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Report for Soufriere Hills
MVO reported that during 22-29 May activity from the Soufrière Hills lava dome was at a low level. On 23 May, a rockfall was detected by the seismic network and contained some low-frequency energy at the onset that may have indicated a small explosion. A small pyroclastic flow on 24 May traveled 1 km E towards the Tar River valley; a resultant ash plume drifted W over Gages Mountain and Plymouth. The Hazard Level remained at 3.
Source: Montserrat Volcano Observatory (MVO)
Report for Tungurahua
The IG reported that Strombolian activity was seen at night from Tungurahua during 26-28 May, followed by nighttime incandescence at the crater through 1 June. The Washington VAAC reported that during 27-29 and 31 May thermal anomalies were seen on satellite imagery. IG also stated that explosions, "cannon shots," and roaring noises were occasionally reported. On 28 May, steam-and-ash plumes rose to an altitude of 7 km (23,000 ft) a.s.l. and drifted W and SW. Blocks rolled 1 km down the flanks. Ashfall was reported downwind during 28-30 May.
Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN), Washington Volcanic Ash Advisory Center (VAAC)
Report for Ubinas
Based on SIGMET notices, the Buenos Aires VAAC reported that on 29 and 31 May eruptions from Ubinas produced ash plumes that rose to altitudes of 5.5-6.7 km (18,000-22,000 ft) a.s.l. and drifted NE and SW. Ash was not detected on satellite imagery on 31 May. INGEMMET reported on 1 June a bluish gas plume with some ash content. On 2 June, an explosion was detected and gas-and-ash plumes that rose 0.9-1.5 km drifted E.
Sources: Buenos Aires Volcanic Ash Advisory Center (VAAC), Instituto Geológico Minero y Metalúrgico (INGEMMET)