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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 March-29 March 2011
Name Country Volcanic Province Eruption Start Date Report Status
Karangetang Indonesia Sangihe Volcanic Arc New
Kilauea United States Hawaiian-Emperor Hotspot Volcano Group 2024 Sep 15 New
Rabaul Papua New Guinea Bismarck Volcanic Arc New
San Miguel El Salvador Central America 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
Bulusan Philippines Eastern Philippine Volcanic Arc Continuing
Karymsky Russia Eastern Kamchatka Volcanic Arc 2024 Jun 20 Continuing
Kirishimayama Japan Ryukyu Volcanic Arc Continuing
Kizimen Russia Eastern Kamchatka Volcanic Arc Continuing
Planchon-Peteroa Chile Southern Andean Volcanic Arc Continuing
Popocatepetl Mexico Trans-Mexican Volcanic Belt 2005 Jan 9 Continuing
Santa Maria Guatemala Central America Volcanic Arc 1922 Jun 22 Continuing
Sheveluch Russia Eastern Kamchatka Volcanic Arc 1999 Aug 15 Continuing
Soufriere Hills United Kingdom Lesser Antilles Volcanic Arc Continuing
Tengger Caldera Indonesia Sunda 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 20,627 individual reports over 1,243 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 Karangetang
CVGHM reported that during 21-23 March incandescent material from Karangetang was ejected 50-75 m above the crater. Lava flows traveled as far as 2 km and collapses from the lava-flow fronts generated avalanches that moved down the flanks up to 300 m further. On 24 March lava was incandescent in areas 1.5 km away from the crater. Incandescent material from the lava-flow fronts rolled an additional 200-500 m down the flanks. Incandescent material was again ejected 75 m above the crater. Later that day, due to decreased seismicity and a decline in the lava-flow effusion rate, the Alert Level was lowered to 3 (on a scale of 1-4).
Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
Report for Kilauea
HVO reported that at Kilauea's east rift zone small areas of incandescence in Pu'u 'O'o crater were visible through the web camera during 23-24 March. The lava lake in the deep pit within Halema'uma'u crater was crusted over; frequent rockfalls produced a few brown-tinged plumes. On 25 March the lava lake reappeared as lava streamed across and eventually covered the floor of the pit. The next day lava returned to Pu'u 'O'o crater about 20 days after the crater floor collapsed on 5 March. Lava slowly filled the deepest parts of the crater forming a lava lake. The lava lake within Halema'uma'u crater again crusted over. During 27-29 March the lava lake in Pu'u 'O'o crater circulated and was fed from two closely-spaced sources in the W center of the lake.
Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
Report for Rabaul
Based on analyses of satellite imagery, the Darwin VAAC reported that on 29 March an ash plume from Rabaul caldera's Tavurvur cone rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted more than 53 km NW.
Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Report for San Miguel
Servicio Nacional de Estudios Territoriales (SNET) reported that during a survey of the San Miguel crater on 9 and 16 March observers noted pulses of gas rising 200 m from the crater. On 12 March the number and amplitude of earthquakes increased. RSAM values rose the next day to 121 units per day on average, up from normal values around 50 units per day. RSAM values continued to fluctuate during the next few days and reached as high as 319 units on 19 March, 414 units on 20 March, and 234 on 21 March. On 18 and 20 March, local residents felt vibrations and heard minor rumbling. Observations on 25 March indicated that gas plumes rose 100 m from the crater. On 28 March SNET noted that seismicity had gradually decreased during the previous few days, and was as low as 80 RSAM units on 27 March. Access to areas within a 2-km-radius remained restricted.
Source: Servicio Nacional de Estudios Territoriales (SNET)
Report for Aira
Based on information from JMA, the Tokyo VAAC reported that during 23-26 and 29 March explosions from Sakura-jima produced plumes that rose to altitudes of 1.2-2.4 km (4,000-8,000 ft) a.s.l. and occasionally drifted E, SE, and S. On 26 March, a pilot observed an ash plume that rose to an altitude of 3.4 km (11,000 ft) a.s.l. and drifted SE.
Source: Tokyo Volcanic Ash Advisory Center (VAAC)
Report for Bagana
Based on analyses of satellite imagery, the Darwin VAAC reported that during 25-28 March ash plumes from Bagana rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted 35-100 km NW, W, and SW.
Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Report for Bulusan
Based on notices from the Manila airport (RPLL), the Tokyo VAAC reported that during 25-26 March ash from Bulusan was observed. PHIVOLCS reported that cloud cover prevented ground-based observations.
Sources: Philippine Institute of Volcanology and Seismology (PHIVOLCS), Tokyo Volcanic Ash Advisory Center (VAAC)
Report for Karymsky
KVERT reported moderate seismic activity at Karymsky during 18-25 March. Seismic data indicated that possible ash plumes rose to an altitude of 3.5 km (11,500 ft) a.s.l. A thermal anomaly was detected in satellite imagery during 19-24 March. The Aviation Color Code remained at Orange.
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Report for Kirishimayama
Based on notifications from JMA, the Tokyo VAAC reported that an eruption from Kirishima's Shinmoe-dake (Shinmoe peak) on 23 March produced a plume that rose to an altitude of 2.4 km (8,000 ft) a.s.l. and drifted SE. Subsequent notices that day stated that the ash had dissipated. An eruption on 29 March produced a plume that rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted SE.
Source: Tokyo Volcanic Ash Advisory Center (VAAC)
Report for Kizimen
KVERT reported that during 18-25 March seismicity from Kizimen was high, with many shallow volcanic earthquakes and volcanic tremor continuing to be detected. Satellite images showed a large bright thermal anomaly daily on the volcano. Ash and gas-and-steam plumes drifted 313 km N and E during 17 and 19-24 March. The Aviation Color Code remained at Orange. Based on analyses of satellite imagery, the Tokyo VAAC reported that during 25-29 March ash was detected in satellite imagery.
Sources: Kamchatkan Volcanic Eruption Response Team (KVERT), Tokyo Volcanic Ash Advisory Center (VAAC)
Report for Planchon-Peteroa
Based on a SIGMET notice, the Buenos Aires VAAC reported ash from an eruption of Planchón-Peteroa on 26 March. Ash was not observed in satellite imagery.
Source: Buenos Aires Volcanic Ash Advisory Center (VAAC)
Report for Popocatepetl
Based on information from the Mexico City MWO, analyses of satellite imagery, and web-camera views, the Washington VAAC reported that on 26 March an ash-and-gas plume from Popocatépetl drifted ESE and SE. A subsequent notice that day stated that the ash had dissipated approximately 140 km SE. On 27 March a small ash plume drifted almost 150 m E.
Source: Washington Volcanic Ash Advisory Center (VAAC)
Report for Santa Maria
INSIVUMEH reported that on 24 March a loud explosion from Santa María's Santiaguito lava dome complex was followed by a pyroclastic flow that descended the E flank. A few hours later an explosion produced an ash plume that rose 600 m above Caliente dome and drifted W. Based on a METAR notice, information from INSIVUMEH, and analyses of satellite imagery, the Washington VAAC reported a diffuse ash plume on 28 March. Explosions reported by INSIVUMEH during 27-28 March produced ash plumes that rose 300-600 m above the dome and drifted over nearby farms and villages. Block avalanches descended the flanks.
Sources: Washington Volcanic Ash Advisory Center (VAAC), Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Report for Sheveluch
KVERT reported that during 18-25 March seismic data at Shiveluch indicated that possible ash plumes rose to an altitude of 5.8 km (19,000 ft) a.s.l. A thermal anomaly on the lava dome was observed daily in satellite imagery, and ash plumes drifted 373 km SE and N during 18-20 March. Ground-based observers noted that ash plumes rose to an altitude of 6 km (19,700 ft) a.s.l. on 22 March. The Tokyo VAAC reported that on 23 March an eruption detected in satellite imagery and reported by KEMSD produced a plume that rose to an altitude of 6.7 km (22,000 ft) a.s.l. Subsequent notices that day stated that ash then dissipated. The Aviation 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 during 18-25 March activity at the Soufrière Hills lava dome was at a low level. A small lahar occurred in the Belham valley (NW) on 19 March. A relatively large pyroclastic flow traveled likely in excess of 2 km down the Tar River valley to the E and a resulting ash plume drifted W over uninhabited areas. The pyroclastic flow was related to the degradation of the lava dome on the E side as recent observations noted undercutting and overhanging areas on that side. The Hazard Level remained at 3.
Source: Montserrat Volcano Observatory (MVO)
Report for Tengger Caldera
CVGHM reported that during 22-25 March brownish-gray ash plumes from Tengger Caldera's Bromo cone rose 400-800 m above the crater and drifted SW, NE, and E. Incandescent material was ejected 300 m above the crater, and landed as far as 500 m away during 22-23 March, 300 m away on 24 March, and 250 m away on 25 March. Roaring and booming was also noted. The Alert Level remained at 3 (on a scale of 1-4). Residents and tourists were not permitted within a 2-km-radius of the active crater.

Based on analyses of satellite imagery, the Darwin VAAC reported that during 27-28 March ash plumes rose to an altitude of 4.3 km (14,000 ft) a.s.l. and drifted 55 km NE.
Sources: Darwin Volcanic Ash Advisory Centre (VAAC), Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)