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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 28 September-4 October 2011
Name Location Eruption Start Date Report Status
Hierro Canary Islands New
Krakatau Sunda Strait New
Nabro Eritrea New
Rincon de la Vieja Costa Rica 2021 Jun 28 New
Sheveluch Central Kamchatka (Russia) 1999 Aug 15 New
Villarrica Central Chile 2014 Dec 2 ± 7 days New
Aira Kyushu (Japan) 2017 Mar 25 Continuing
Cleveland Chuginadak Island (USA) Continuing
Etna Sicily (Italy) 2022 Nov 27 Continuing
Karymsky Eastern Kamchatka (Russia) Continuing
Kilauea Hawaiian Islands (USA) Continuing
Kizimen Eastern Kamchatka (Russia) Continuing
Puyehue-Cordon Caulle Central Chile Continuing
Santa Maria Southwestern Guatemala 1922 Jun 22 Continuing
All times are local unless otherwise stated.
Weekly Reports Archive

Since the Weekly Volcanic Activity Report began in November 2000, there have been 19,934 individual reports over 1,212 weeks (average of 16 per week) on 332 different volcanoes.

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Agung Cuicocha Iliwerung Llaima Popocatepetl Sumbing
Ahyi Cumbal Inielika Lokon-Empung Purace Sundoro
Aira Dabbahu Ioto Lonquimay Puyehue-Cordon Caulle Suretamatai
Akan Davidof Irazu Lopevi Rabaul Suwanosejima
Alaid Dempo Iya Machin Raikoke Taal
Alu-Dalafilla Descabezado Grande Izu-Torishima Makushin Ranakah Tair, Jebel at
Ambae Dieng Volcanic Complex Jackson Segment Maly Semyachik Raoul Island Takawangha
Ambang Dukono Kaba Manam Rasshua Talang
Ambrym East Epi Kadovar Manda Hararo Raung Tambora
Anatahan Ebeko Kaitoku Seamount Marapi Redoubt Tanaga
Aniakchak Ebulobo Kama'ehuakanaloa Maroa Reventador Tandikat-Singgalang
Antillanca Volcanic Complex Edgecumbe Kambalny Martin Reykjanes Tangkoko-Duasudara
Antuco Egon Kanaga Masaya Rincon de la Vieja Tangkuban Parahu
Apoyeque Ekarma Kanlaon Maule, Laguna del Rinjani Tara, Batu
Arenal Eldey Karangetang Mauna Loa Ritter Island Ta'u
Asamayama Erebus Karkar Mayon Rotorua Taupo
Askja Erta Ale Karthala McDonald Islands Ruang Telica
Asosan Etna Karymsky Melebingoy Ruapehu Tenerife
Atka Volcanic Complex Etorofu-Yakeyama [Grozny Group] Kasatochi Melimoyu Ruby Tengger Caldera
Augustine Eyjafjallajokull Katla Merapi Ruiz, Nevado del Three Sisters
Avachinsky Fagradalsfjall Katmai Midagahara Sabancaya Tinakula
Awu Fernandina Kavachi Misti, El Sakar Tofua
Axial Seamount Fogo Kelimutu Miyakejima Salak Tokachidake
Azul, Cerro Fonualei Kelud Momotombo San Cristobal Tolbachik
Azumayama Fournaise, Piton de la Kerinci Monowai San Miguel Toliman
Bagana Fourpeaked Ketoi Montagu Island San Vicente Tongariro
Balbi Fuego Kharimkotan Moyorodake [Medvezhia] Sangay Trident
Bamus Fujisan Kick 'em Jenny Mutnovsky Sangeang Api Tungurahua
Banda Api Fukutoku-Oka-no-Ba Kie Besi Myojinsho Santa Ana Turrialba
Bardarbunga Galeras Kikai Nabro Santa Maria Ubinas
Barren Island Galunggung Kilauea Negra, Sierra Sao Jorge Ugashik-Peulik
Batur Gamalama Kirishimayama Negro, Cerro Sarigan Ukinrek Maars
Bezymianny Gamkonora Kita-Ioto Nightingale Island Sarychev Peak Ulawun
Bogoslof Gareloi Kizimen Nishinoshima Saunders Unnamed
Brava Gaua Klyuchevskoy Nisyros Savo Unnamed
Bristol Island Gorely Kolokol Group Novarupta Semeru Veniaminof
Bulusan Great Sitkin Koryaksky NW Rota-1 Semisopochnoi Villarrica
Calbuco Grimsvotn Krakatau Nyamulagira Seulawah Agam Vulcano
Callaqui Guagua Pichincha Krummel-Garbuna-Welcker Nyiragongo Sheveluch West Mata
Cameroon Guallatiri Krysuvik-Trolladyngja Ofu-Olosega Shishaldin Westdahl
Campi Flegrei del Mar di Sicilia Guntur Kuchinoerabujima Okataina Simbo Whakaari/White Island
Cayambe Hachijojima Kurikomayama Okmok Sinabung Witori
Chachadake [Tiatia] Hakoneyama Kusatsu-Shiranesan Ontakesan Sinarka Wolf
Chaiten Heard Kverkfjoll Oraefajokull Siple Wrangell
Chiginagak Hekla La Palma Osorno Sirung Yakedake
Chikurachki Helgrindur Lamington Pacaya Slamet Yasur
Chiles-Cerro Negro Hierro Lamongan Pagan Snaefellsjokull Yufu-Tsurumi
Chillan, Nevados de Hokkaido-Komagatake Langila Palena Volcanic Group Soputan Zaozan [Zaosan]
Chirinkotan Home Reef Lanin Paluweh Sorikmarapi Zavodovski
Chirpoi Hood Lascar Panarea Sotara Zhupanovsky
Ciremai Huaynaputina Late Papandayan Soufriere Hills Zubair Group
Cleveland Hudson, Cerro Lateiki Pavlof Soufriere St. Vincent
Colima Huila, Nevado del Lengai, Ol Doinyo Pelee South Sarigan Seamount
Colo Hunga Tonga-Hunga Ha'apai Leroboleng Peuet Sague Spurr
Concepcion Ibu Lewotobi Pinatubo St. Helens
Copahue Ijen Lewotolok Planchon-Peteroa Stromboli
Cotopaxi Iliamna Little Sitkin Poas Sulu Range
 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 Hierro
Instituto Geográfico Nacional (IGN) reported a drastic increase in the seismic activity at Hierro during 27 September-3 October, with more than 1,100 new seismic events detected, 83 of them felt by residents, with a maximum intensity value of IV using EMS-98 (European Macroseismic Scale). Most of the hypocenters were located offshore, SW of the island, at around 14 km depth. The maximum magnitude recorded during this week was 3.8. The total number of located events had reached more than 9,300 since the anomalous activity began on 16 July. The superficial deformation measured by the GPS network had reached 35 mm.
Source: Instituto Geográfico Nacional (IGN)
Report for Krakatau
CVGHM reported that seismicity from Anak Krakatau in 2011, as late as 10 July, consisted of 20-30 volcanic-earthquake events per day and shallow events ranged from 120 to 135 events per day. Hundreds of events per day were detected during swarms. On 10 July, the seismic equipment was damaged by Krakatau's activity but was again operational in mid-September. During 18-30 September seismic events reached 4-5 events per minute. Visual observations in 2011 until 13 September indicated occasional explosive eruptions that would eject material and produce ash plumes. During 14-30 September fumarolic activity from the crater and in the fumarolic fields was visible. The Alert Level was increased to 3 (on a scale of 1-4) on 30 September based on an increase in seismic activity and widespread fumarolic activity.
Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
Report for Nabro
According to NASA's Earth Observatory, satellite images of Nabro acquired on 28 September showed heat from the vent in the central crater, and from an area 1.3 km S of the vent that indicated an active lava flow. A small and diffuse plume rose from the vent. A region of seemingly thicker black ash (that completely covered the sparse vegetation) was noted S of the crater and thinner layers of ash (with some areas of visible vegetation) flanked either side of the region.
Source: NASA Earth Observatory
Report for Rincon de la Vieja
On 30 September, OVSICORI-UNA reported phreatic eruptions from Rincón de la Vieja's active crater during the previous six weeks. A well-documented event on 16 September ejected sediment that covered sections of the upper N walls. Some of the material was washed down the flanks and caused changes in water quality along the main creeks and major rivers up to 18 km away from the source. The death of several fish species was noted the next day and sediment deposits 10-15 cm deep were sampled 2 km N of the active crater. Scientists conducting fieldwork during 27-29 September observed that the hot lake was convecting and grayish in color due to the suspended sediments. Preliminary deformation and temperature measurements did not indicate any significant changes.
Source: Observatorio Vulcanologico y Sismologico de Costa Rica-Universidad Nacional (OVSICORI-UNA)
Report for Sheveluch
KVERT reported that seismic activity at Shiveluch was moderate during 23-30 September, and indicated that possible ash plumes rose to an altitude of 4.6 km (15,100 ft) a.s.l. during 23 and 26-27 September. Ground-based observers noted that ash plumes rose to altitudes of 5.5 and 4.5 km (18,000 and 14,800 ft) a.s.l. on 23 and 27 September, respectively. Ash plumes observed in satellite imagery during 23-24 September drifted 45 km E. Seismicity increased on 3 October. Ash plumes rose to altitudes of 6-9 km (19,700-29,500 ft) a.s.l. during 3-5 October. Ground-based observers noted on 5 October a brightly incandescent lava dome, which was also detected as a large and bright thermal anomaly in satellite imagery. The Aviation Color Code was raised to Red.
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Report for Villarrica
According to Projecto Observación Visual Volcán Villarrica (POVI), an image from 17 September showed the inner SSW wall of the crater covered with snow and ice, and a thin layer of ash. A rapid rise in the level of the lava lake (in a pit about 40 m wide) on 19 September caused much of the snow and ice to melt, especially on the southern inner wall. Strombolian explosions from the crater were observed on 26 September, and tephra deposits on the E edge of the crater were noted. On 27 September incandescence from the lava lake were reflected in the cloud cover above.
Source: Proyecto Observación Villarrica Internet (POVI)
Report for Aira
Based on information from JMA, the Tokyo VAAC reported that during 28 September-3 October explosions from Sakura-jima produced plumes that rose to altitudes of 1.8-3 km (6,000-10,000 ft) a.s.l. and drifted in multiple directions. On 30 September and during 1-2 October pilots observed ash plumes that rose to altitudes of 1.5-3 km (5,000-10,000 ft) a.s.l. and mostly drifted NE, E, and ESE.
Source: Tokyo Volcanic Ash Advisory Center (VAAC)
Report for Cleveland
AVO reported that during 27-28 September and 30 September-1 October thermal anomalies over Cleveland's summit lava dome were detected in satellite images and suggested that the lava dome continued to slowly grow. Clouds obscured views on 29 September and during 2-3 October. Elevated surface temperatures were detected by satellite in partly cloudy images acquired during 3-4 October. The Volcano Alert Level remained at Watch and the Aviation Color Code remained at Orange. No current seismic information was available because Cleveland does not have a real-time seismic network.
Source: US Geological Survey Alaska Volcano Observatory (AVO)
Report for Etna
Sezione di Catania - Osservatorio Etneo reported that the fifteenth paroxysmal eruptive episode of 2011 took place at the New SE Crater of Etna during the evening of 28 September. That morning, noises originated from the New SE Crater. At 1600 volcanic tremor amplitude started to increase, and rhythmic ash emissions that rose from a vent located within the crater were occasionally accompanied by small Strombolian explosions. Starting at 1930 Strombolian activity progressively increased both in the intensity and frequency of explosions, and eventually became continuous. Bombs and scoria were ejected well beyond the crater rim. A small amount of lava flowed through the notch in the SE flank of the volcano at 2115 and was soon followed by explosions from a vent within the same area. The Strombolian activity waned for a few minutes then rapidly increased, forming a sustained lava fountain that rose as high as 800 m. At 2133 and 2134 two powerful explosions originating from a vent on the E rim of the crater created shock waves visible in the clouds above the crater and ejected large bombs hundreds of meters away. Lava fountains 100-150 m high commenced from a vent on the N base of the New SE Crater cone at 2136. The vent emitted a small lava flow soon after. At 2155 activity from all vents decreased, and between 2205 and 2210 all explosive activity ceased. Lava continued to flow until 2330.

The lava flow emitted from the SE flank of the cone reached the lower portion of the W slope of the Valle del Bove, somewhat SW of Monte Centenari. Ash plumes drifted SW and light ashfall occurred on the S flank of Etna, including in the towns of Nicolosi (14 km S) and Catania (27 km S).
Source: Sezione di Catania - Osservatorio Etneo (INGV)
Report for Karymsky
KVERT reported that seismic activity continued at a moderate level at Karymsky during 23-30 September and indicated that possible ash plumes rose to an altitude of 4.5 km (14,800 ft) a.s.l. Satellite imagery showed a thermal anomaly on the volcano on 24 September and ash plumes that drifted 80 km SE during 28-29 September. The Aviation Color Code remained at Orange.
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Report for Kilauea
During 28 September-4 October, HVO reported that the lava lake circulated and periodically rose and fell in the deep pit within Kilauea's Halema'uma'u crater. Almost daily measurements indicated that the gas plume from the vent continued to deposit variable amounts of ash and occasionally fresh spatter nearby.

At the E rift zone, the fissure that formed on 21 September on the upper E flank of Pu'u 'O'o continued to feed lava flows on 28 September that traveled along the edges of a low lava ridge. Most of the active lava spread out at higher elevations S and W of Pu'u Halulu (1.3 km NE of Pu'u 'O'o). Lava activity resumed from two sources on the E edge of the Pu'u 'O'o Crater floor and continued to spread W within the crater. During an overflight on 29 September, geologists observed that the fissure fed scattered active lava flows within 1.8 km on the SE flank of the cone. During 2-3 October lava from the E-crater floor source covered the crater floor. On 4 October active lava was confined to a small lake on the E side of the crater floor.
Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
Report for Kizimen
KVERT reported that during 23-30 September seismicity at Kizimen remained high with 1,200-1,600 earthquakes recorded daily. A large thermal anomaly on the volcano was detected daily in satellite images. A large lava flow on the NE flank continued to effuse and strong fumarolic activity was observed. The Aviation Color Code remained at Orange.
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Report for Puyehue-Cordon Caulle
Based on seismicity during 28 September-4 October, OVDAS-SERNAGEOMIN reported that the eruption from the Cordón Caulle rift zone, part of the Puyehue-Cordón Caulle volcanic complex, continued at a low level. Plumes visible in satellite images drifted 30-300 km NW, NE, E, and SE during 28 September-3 October. Plumes were also observed with an area camera to rise as high as 4 km during 30 September-4 October. The Alert Level remained at Red.
Source: Servicio Nacional de Geología y Minería (SERNAGEOMIN)
Report for Santa Maria
INSIVUMEH reported that on 29 September a lahar 28 m wide and 2 m deep traveled down Santa María's Rio Nima II drainage, carrying 2-m-wide blocks and tree branches. During 29-30 September and 3-4 October explosions from the Santiaguito lava dome complex produced gray ash plumes that rose 1 km above the crater and drifted 15 km E and SW. Avalanches from the lava-flow fronts descended the flanks. During 3-4 October avalanches from the lava dome occasionally generated pyroclastic flows; lava flows were active on the SW and SE flanks.
Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)