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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 16 September-22 September 2015
Name Country Volcanic Province Eruption Start Date Report Status
Aira Japan Ryukyu Volcanic Arc 2017 Mar 25 New
Asosan Japan Nankai Volcanic Arc New
Cotopaxi Ecuador Northern Andean Volcanic Arc New
Mauna Loa United States Hawaiian-Emperor Hotspot Volcano Group New
Nevado del Ruiz Colombia Northern Andean Volcanic Arc 2014 Nov 18 New
Piton de la Fournaise France Reunion Hotspot Volcano Group New
Batu Tara Indonesia Sunda Volcanic Arc Continuing
Cleveland United States Aleutian Ridge Volcanic Arc Continuing
Colima Mexico Trans-Mexican Volcanic Belt Continuing
Dukono Indonesia Halmahera Volcanic Arc 1933 Aug 13 Continuing
Karangetang Indonesia Sangihe Volcanic Arc Continuing
Karymsky Russia Eastern Kamchatka Volcanic Arc 2024 Jun 20 Continuing
Kilauea United States Hawaiian-Emperor Hotspot Volcano Group 2024 Sep 15 Continuing
Pacaya Guatemala Central America Volcanic Arc Continuing
Popocatepetl Mexico Trans-Mexican Volcanic Belt 2005 Jan 9 Continuing
Sheveluch Russia Eastern Kamchatka Volcanic Arc 1999 Aug 15 Continuing
Shishaldin United States Aleutian Ridge Volcanic Arc Continuing
Sinabung Indonesia Sunda Volcanic Arc Continuing
Soufriere Hills United Kingdom Lesser Antilles Volcanic Arc Continuing
Ubinas Peru Central Andean 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 20,764 individual reports over 1,249 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 Aira
JMA reported that small explosions occasionally occurred at Minamidake Crater at Aira Caldera’s Sakurajima during 14-21 September. On 16 and 18 September an explosion from Showa Crater ejected tephra as far as 800 m, and incandescence from the crater was occasionally visible at night. The Alert Level remained at 3 (on a 5-level scale).
Source: Japan Meteorological Agency (JMA)
Report for Asosan
On 18 September JMA reported that an eruption from Asosan’s Nakadake Crater continued; ash plumes rose 900 m that same day. During an overflight scientists observed that pyroclastic-flow deposits from the 14 September explosion extended down the SE flank as far as 3 km; scientists from Kumamoto University estimated that about [40,000 tons] of ash were ejected that day. On 21 September an off-white plume rose 900 m. The Alert Level remained at 3 (on a scale of 1-5).
Source: Japan Meteorological Agency (JMA)
Report for Cotopaxi
On 17 September IG reported that during the previous two weeks activity at Cotopaxi had declined, characterized by a decrease in tremor and less intense gas-and-ash emissions. On 10 September, however, the number of volcano-tectonic events increased. They were mostly located 9-12 km below the summit, although some were as shallow as 4 km. During 19-22 September gas emissions with low ash content rose as high as 1.5 km above the crater and drifted W.
Source: Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN)
Report for Mauna Loa
On 18 September HVO reported that for at least the previous year the seismic network at Mauna Loa detected elevated seismicity beneath the summit, upper Southwest Rift Zone, and W flank; the rate of these shallow earthquakes varied but overall had remained above the long-term average. The earthquakes locations were similar to those preceding recent eruptions in 1975 and 1984, although the magnitudes were comparatively low. In addition, ground deformation consistent with recharge of the volcano’s shallow magma storage system was also detected during the previous year. The rate and pattern of the deformation was similar to that measured during a period of inflation 2005, unrest that did not lead to an eruption. However, since the observations indicated that Mauna Loa is no longer at background levels, HVO raised the Aviation Color Code to Yellow and the Volcano Alert Level to Advisory.
Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
Report for Nevado del Ruiz
Servicio Geológico Colombiano’s (SGC) Observatorio Vulcanológico y Sismológico de Manizales reported that during 15-21 September seismicity at Nevado del Ruiz was characterized by long-period earthquakes and short-duration volcanic tremor associated with gas-and-ash emissions. Increases in seismicity were detected on 15 and 20 September, SW and N of Arenas Crater, respectively; the earthquakes were located at depths between 2.2 and 6.5 km, and were a maximum local M 2. Water-vapor-and-gas plumes rose 2.5 km above the crater and drifted mainly NW, and were sometimes tinged gray due to the presence of ash. Ashfall was reported in Manizales (30 km NW) and Pereira (40 km WSW). The Alert Level remained at III (Yellow; "changes in the behavior of volcanic activity").
Source: Servicio Geológico Colombiano (SGC)
Report for Piton de la Fournaise
On 14 September OVPDLF reported that during the previous several days seismicity, deformation, and gas emissions at Piton de la Fournaise intensified. Tremor levels fluctuated. The two lava lakes separated by a partition in a single vent remained active. Lava flows emerged from and were active beyond a 50-100 m lava tube; the largest lava flows were not longer than 1.5 km. By 17 September seismic activity, deformation, and gas emissions had stabilized, and only one lava lake was active.
Source: Observatoire Volcanologique du Piton de la Fournaise (OVPF)
Report for Batu Tara
Based on a pilot observation, the Darwin VAAC reported that on 15 September an ash plume from Batu Tara drifted 185 km NW at an altitude of 1.5 km (5,000 ft) a.s.l.
Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Report for Cleveland
AVO reported that during 16-22 September low-level unrest at Cleveland continued. Weakly elevated surface temperatures were detected in one satellite image during 20-21 September. The Aviation Color Code remained at Orange and the Volcano Alert Level remained at Watch.
Source: US Geological Survey Alaska Volcano Observatory (AVO)
Report for Colima
On 18 September the Washington VAAC reported that the webcam at Colima recorded a short-duration ash plume that rose to an altitude of 5.2 km (17,000 ft) a.s.l. Based on satellite images, the Mexico City MWO, and seismic data, the VAAC noted that during 20-21 September ash plumes rose to altitudes of 5.5-6.7 km (18,000-22,000 ft) a.s.l. and drifted km W and WSW.
Source: Washington Volcanic Ash Advisory Center (VAAC)
Report for Dukono
Based on analyses of satellite imagery and wind data, the Darwin VAAC reported that during 16-21 September ash plumes from Dukono rose to altitudes of 2.1-2.7 km (7,000-9,000 ft) a.s.l. and drifted 65-85 km NE, E, and SE.
Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Report for Karangetang
Based on observations conducted at the Karangetang Volcano Observation Post in the village of Salili, PVMBG reported during 9-16 September that lava fountains rose as high as 250 m and lava flows traveled as far as 2.5 km. Incandescent avalanches from the fronts of 150-m-long lava flows traveled as far as 2.5 km E down the Batuawang and Kahetang drainages. Seismicity was dominated by multi-phase earthquakes and signals characteristic of avalanches, with rare volcanic earthquakes. The Alert Level remained at 3 (on a scale of 1-4); visitors and residents were warned not to approach Karangetang within a 4-km radius.

Based on analyses of satellite imagery and wind data, the Darwin VAAC reported that during 16-17 September ash plumes rose to altitudes of 2.4-3 km (6,000-10,000 ft) a.s.l. and drifted 30-85 km NE, E, and ESE.
Sources: Darwin Volcanic Ash Advisory Centre (VAAC), Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
Report for Karymsky
KVERT reported that moderate explosive activity at Karymsky continued during 11-18 September. Satellite images detected a thermal anomaly on the volcano during 14-18 September. The Aviation Color Code remained at Orange.
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Report for Kilauea
HVO reported that seismicity and deformation at Kilauea was at normal levels during 16-22 September. The lava lake rose and fell, circulated, and occasionally spattered in the Overlook vent. Webcams recorded multiple incandescent outgassing vents within Pu'u 'O'o. The June 27th NE-trending lava flow continued to be active within 4-8 km NE of Pu'u 'O'o Crater; smoke plumes from burning vegetation marked the most distal flows.
Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
Report for Pacaya
INSIVUMEH reported that during 17-19 September white-and-blue fumarolic plumes rose from Pacaya's Mackenney cone and drifted W and S. Tremor was detected and incandescence from the crater was visible at night. Weak explosions on 22 September generated an ash plume that rose 900 m above the crater and drifted W. Tremor continued to be recorded.
Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Report for Popocatepetl
CENAPRED reported that during 16-22 September the seismic network at Popocatépetl recorded 15-89 daily emissions consisting of water vapor, gas, and sometimes ash; cloud cover often prevented visual observations. Variable nighttime or morning crater incandescence was observed most days, and 1-13 daily explosions were registered. The Alert Level remained at Yellow, Phase Two.
Source: Centro Nacional de Prevencion de Desastres (CENAPRED)
Report for Sheveluch
KVERT reported that during 11-18 September lava-dome extrusion onto Sheveluch’s N flank was accompanied by fumarolic activity, dome incandescence, and hot avalanches. Satellite images detected a daily thermal anomaly over the dome. Based on video and satellite data, re-suspended ash from strong winds drifted 185 km SE during 15-16 September. The Aviation Color Code remained at Orange.
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Report for Shishaldin
AVO reported that seismicity at Shishaldin was only slightly above background levels during 16-22 September. No activity was observed in satellite or webcam images during clear periods. The Aviation Color Code remained at Orange and the Volcano Alert Level remained at Watch.
Source: US Geological Survey Alaska Volcano Observatory (AVO)
Report for Sinabung
PVMBG reported that during 8-14 September foggy weather sometimes prevented visual observations of Sinabung and the growing lava dome in the summit crater. Lava flows on the flanks were incandescent as far as 2 km ESE. As many as six pyroclastic flows per day were detected, traveling as far as 3.5 km ESE and SE. Ash plumes rose as high as 2.5 km. Seismicity consisted of avalanche signals, low-frequency and hybrid events, tremor, tectonic events, and volcanic earthquakes. Seismicity fluctuated, although it had declined compared to the previous week. Deformation measurements showed deflation. The Alert Level remained at 4 (on a scale of 1-4), indicating that people within 7 km of the volcano on the SSE sector, and within 6 km in the ESE sector, should evacuate. Based on information from PVMBG, the Darwin VAAC reported that on 18 September an ash plume from a pyroclastic flow rose to an altitude of 3.3 km (11,000 ft) a.s.l. On 21 September an ash plume rose to an altitude of 4.3 km (14,000 ft) a.s.l. and drifted SW. Later that day a pilot observed an ash plume drifting 45 km SW at an altitude of 5.8 km (19,000 ft) a.s.l.
Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
Report for Soufriere Hills
Based on satellite image analyses and wind data, the Washington VAAC reported that on 19 September possible re-suspended ash from Soufrière Hills drifted WNW at an altitude of 1 km (3,000 ft) a.s.l.
Source: Washington Volcanic Ash Advisory Center (VAAC)
Report for Ubinas
Instituto Geofísico del Perú (IGP) Observatorio Volcanológico del Sur (OVS) reported that long-period and volcano-tectonic events were at low levels at Ubinas during 15-21 September. Sporadic steam-and-gas plumes rose 600 m. Seismicity (hybrid and long-period events) increased during 20-21 September. An explosion on 21 September at 0914 produced ash plumes that rose 1.7 km and drifted S; ash emission continued until about 0800 the next day. Ashfall was reported in Querapi (4.5 km SE), Ubinas (6.5 km SSE), Tonohaya (7 km SSE), Anascapa (11 km SE), Sacohaya, and San Miguel (10 km SE).
Source: Instituto Geofísico del Perú (IGP)