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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 6 July-12 July 2016
Name Country Volcanic Province Eruption Start Date Report Status
Bulusan Philippines Eastern Philippine Volcanic Arc New
Copahue Chile-Argentina Southern Andean Volcanic Arc New
Kilauea United States Hawaiian-Emperor Hotspot Volcano Group 2024 Sep 15 New
Pacaya Guatemala Central America Volcanic Arc New
Alaid Russia Kuril Volcanic Arc Continuing
Bagana Papua New Guinea Solomon Volcanic Arc 2000 Feb 28 (in or before) Continuing
Chirpoi Russia Kuril Volcanic Arc Continuing
Dukono Indonesia Halmahera Volcanic Arc 1933 Aug 13 Continuing
Fuego Guatemala Central America Volcanic Arc 2002 Jan 4 Continuing
Klyuchevskoy Russia Eastern Kamchatka Volcanic Arc Continuing
Nevado del Ruiz Colombia Northern Andean Volcanic Arc 2014 Nov 18 Continuing
Pavlof United States Aleutian Ridge Volcanic Arc Continuing
Santa Maria Guatemala Central America Volcanic Arc 1922 Jun 22 Continuing
Sheveluch Russia Eastern Kamchatka Volcanic Arc 1999 Aug 15 Continuing
Sinabung Indonesia Sunda Volcanic Arc Continuing
Tengger Caldera Indonesia Sunda Volcanic Arc 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 20,652 individual reports over 1,244 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 Bulusan
PHIVOLCS reported that on 5 July voluminous emissions of white-to-grayish-white steam plumes rose 250 m above Bulusan's summit crater, and drifted SSE and SSW. Copious amounts of white steam rose 700 m above the crater the next day. During 7-9 July cloud cover obscured views of the crater. Diffuse white steam plumes drifted down the flanks on 10 July and rose as high as 70 m during 11-12 July. The Alert Level remained at 1, indicating abnormal conditions and a 4-km-radius Permanent Danger Zone (PDZ).
Source: Philippine Institute of Volcanology and Seismology (PHIVOLCS)
Report for Copahue
OVDAS- SERNAGEOMIN reported that during 16-30 June the eruption at Copahue was characterized by phreato-magmatic explosions and Strombolian activity. On 4 July, SERNAGEOMIN posted on their social media page photos from an overflight showing Strombolian activity from a crater atop of a pyroclastic cone which was forming on the floor of El Agrio crater. Based on webcam and satellite views, the Buenos Aires VAAC reported that during 7-8 July diffuse gas-and-steam plumes with minor amounts of ash rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted E and SE. The Alert Level remained at Yellow; SERNAGEOMIN recommended no entry into a restricted area within 1.5 km of the crater.
Sources: Servicio Nacional de Geología y Minería (SERNAGEOMIN), Buenos Aires Volcanic Ash Advisory Center (VAAC)
Report for Kilauea
HVO reported that during 6-12 July the lava lake continued to rise and fall, circulate, and spatter in Kilauea's Overlook vent. Several incandescent vents on Pu'u 'O'o Crater's floor were evident in webcam images. Episode 61g, a lava flow originating from a vent on Pu'u 'O'o Crater's E flank, continued to advance across the coastal plain, burning vegetation in the adjacent kipuka at the base of the pali. By 10 July the lava flow was about 1 km from the ocean.
Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
Report for Pacaya
INSIVUMEH reported that Strombolian explosions from Pacaya's Mackenney cone were observed during 7-10 July. During 11-12 July weather conditions prevented visual observations of the crater, although weak crater incandescence was visible at night.
Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Report for Alaid
KVERT reported that Strombolian activity at a new cinder cone in Alaid's summit crater was detected during 1-8 July, and lava flowed down the SW flank. Satellite images showed a daily thermal anomaly at the volcano, and ash plumes drifting 150 km SW during 3-4 July. 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 Bagana
Based on analyses of satellite imagery and model data, the Darwin VAAC reported that during 6-10 July ash plumes from Bagana rose to altitude of 2.1-2.7 km (7,000-9,000 ft) a.s.l. and drifted as far as 120 km SE, SW, W, and NW.
Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Report for Chirpoi
SVERT reported that a thermal anomaly over Snow, a volcano of Chirpoi, was detected in satellite images during 5-7 July. The Aviation Color Code remained at Yellow.
Source: Sakhalin Volcanic Eruption Response Team (SVERT)
Report for Dukono
Based on analyses of satellite imagery and model data, the Darwin VAAC reported that during 6-10 and 12 July ash plumes from Dukono rose to altitudes of 1.8-2.4 km (6,000-8,000 ft) a.s.l. and drifted in multiple directions.
Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Report for Fuego
INSIVUMEH reported that during 7-10 July there were 6-8 explosions per hour at Fuego, generating ash plumes that rose as high as 950 m above the crater and drifted W and NW. Ash fell in Yepocapa (8 km N), Sangre de Cristo (8 km WSW), Panimache (8 km SW), and other nearby areas. Some explosions generated shock waves, and incandescent material was ejected 150 m high. There were 18 explosions detected during 11-12 July; ash plumes rose as high as 850 m and drifted more than 10 km W and SW.
Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Report for Klyuchevskoy
KVERT reported that a Strombolian eruption at Klyuchevskoy continued during 1-8 July. Volcanic bombs were ejected 200-300 m above the summit crater and 50 m above a cinder cone, and landed in the Apakhonchich drainage on the SE flank. A lava flow traveled down the Apakhonchich drainage. Satellite images showed a large and intense daily thermal anomaly at the volcano, and ash plumes drifting 350 km SW, S, and SE during 2-5 July. Video data showed that activity intensified on 6 July; strong explosions generated ash plumes that rose as high as 7.5 km (24,600 ft) a.s.l. Satellite images showed dense ash plumes drifting 400 km SE and E during 6-7 July. The Aviation Color Code remained at Orange.
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Report for Nevado del Ruiz
Servicio Geológico Colombiano’s (SGC) Observatorio Vulcanológico y Sismológico de Manizales reported that a webcam recorded minor ash emissions rising from Nevado del Ruiz during 6-7 July. Based on notices from the Bogota MWO, satellite images, and model data, the Washington VAAC reported that on 8 July ash plumes rose to altitudes of 6.1-6.4 km (20,000-21,000 ft) a.s.l. and drifted W. A thermal anomaly was visible on 9 July. The Alert Level remained at III (Yellow; "changes in the behavior of volcanic activity").
Sources: Servicio Geológico Colombiano (SGC), Washington Volcanic Ash Advisory Center (VAAC)
Report for Pavlof
On 11 July, AVO noted that during the previous 24 hours a steam cloud from Pavlof was seen drifting SW by observers in Sand Point (90 km E) and by pilots flying near the volcano. Satellite images showed the cloud drifting 72 km SW. No unusual seismicity was detected. At 1300 the webcam recorded a minor ash emission rising tens of meters and drifting a few kilometers SW. The Aviation Color Code remained at Yellow and Volcano Alert Level remained at Advisory.
Source: US Geological Survey Alaska Volcano Observatory (AVO)
Report for Santa Maria
INSIVUMEH reported that during 7-8 July explosions at Santa María's Santiaguito lava-dome complex generated ash plumes that rose as high as 1 km and drifted 10 km S and W. On 10 July a strong, loud explosion was followed by pyroclastic flows that traveled 2 km down the S and SW flanks, and an ash plume that rose 3 km and drifted 40 km W. INSIVUMEH reminded the public to stay at least 5 km away from the volcano. Gas plumes rose from the crater during 11-12 July.
Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Report for Sheveluch
KVERT reported that during 1-8 July lava-dome extrusion onto Sheveluch’s N flank was accompanied by strong fumarolic activity, dome incandescence, ash explosions, and hot avalanches. Satellite images showed a thermal anomaly over the dome. On 4 July re-suspended ash from the vicinity of Sheveluch drifted 65 km SE. The Aviation Color Code remained at Orange.
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Report for Sinabung
Based on satellite images, model data, notices from the Jarkarta MWO, and information from PVMBG, the Darwin VAAC reported that during 6, 8-9, and 11 July ash plumes from Sinabung rose to altitudes of 3.7-5.5 km (12,000-18,000 ft) a.s.l. and drifted SE, E, NE, and W.
Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Report for Tengger Caldera
Based on satellite images, wind data, and information from PVMBG, the Darwin VAAC reported that during 6-12 July ash plumes from Tengger Caldera's Bromo cone rose to altitudes of 2.7-3 km (9,000-10,000 ft) a.s.l. and drifted as far as 120 km S, SSW, SW, and W. BNPB reported that the Abdul Rachman Saleh Airport in Malang (26 km W) closed from 2300 on 11 July to 0900 on 12 July due to thin ash deposits around the airport. The Alert Level remained at 2 (on a scale of 1-4); residents and visitors were reminded not to approach the crater within a radius of 1 km.
Sources: Darwin Volcanic Ash Advisory Centre (VAAC), Badan Nacional Penanggulangan Bencana (BNPB)
Report for Turrialba
OVSICORI-UNA reported that strong tremor at Turrialba started at 0658 on 7 July. An accompanying explosion produced an ash plume that rose 1 km above the crater and likely drifted WNW and WSW. Weather conditions mostly prevented views of the crater, although at 1551 a large amount of water-vapor-and-gas emissions with minor amounts of ash were observed. Ashfall was recorded in areas downwind including in neighborhoods of San José (Coronado, La Uruca, Tibás, Rancho Redondo, Guadalupe, Sabanilla, Moravia, Ipís, Sabanilla, La Guácima of Alajuela, and San Rafael de Alajuela), Heredia (38 km W), and Turrubares. Almost continuous tremor was detected through the next day; a period of increased tremor amplitude was detected during 1030-1230. Emissions of gas, water vapor, and large amounts of ash were visible with the webcam. Ash fell in many of the same areas as the day before. Tremor levels dropped at 2030, though increased again at 0030 on 9 July. Ash emissions rose no higher than 500 m above the crater around 0900 on 9 July. Ash emissions to 300 m above the crater and elevated tremor levels continued throughout the day. Ashfall was reported in Ipís de Guadalupe and San Rafael de Heredia. Tremor significantly declined at 0115 on 10 July. Views of the crater at 0600 showed emissions of water vapor and gas with minor amounts of ash. Tremor again increased on 11 July, at 0930, and a possible ash emission occurred between 1000 and 1030, although weather conditions prevented confirmation.
Source: Observatorio Vulcanologico y Sismologico de Costa Rica-Universidad Nacional (OVSICORI-UNA)