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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 29 September-5 October 2021
Name Location Eruption Start Date Report Status
Kilauea Hawaiian Islands (USA) New
La Palma Canary Islands New
Nyiragongo DR Congo New
Vulcano Aeolian Islands (Italy) New
Aira Kyushu (Japan) 2017 Mar 25 Continuing
Fagradalsfjall Iceland Continuing
Great Sitkin Andreanof Islands (USA) 2021 May 25 Continuing
Karymsky Eastern Kamchatka (Russia) Continuing
Katmai Alaska Continuing
Klyuchevskoy Central Kamchatka (Russia) 2023 Jun 22 Continuing
Langila New Britain (Papua New Guinea) 2015 Oct 22 (?) Continuing
Lewotolok Lembata Island 2020 Nov 27 Continuing
Merapi Central Java 2020 Dec 31 Continuing
Pavlof Alaska Peninsula, Alaska Continuing
Reventador Ecuador 2008 Jul 27 Continuing
Sangay Ecuador 2019 Mar 26 Continuing
Semisopochnoi Aleutian Islands (USA) Continuing
Sheveluch Central Kamchatka (Russia) 1999 Aug 15 Continuing
Suwanosejima Ryukyu Islands (Japan) 2004 Oct 23 Continuing
Taal Luzon (Philippines) Continuing
Telica Sierra de los Marrabios Continuing
Yasur Vanuatu 1270 ± 110 years Continuing
All times are local unless otherwise stated.
Weekly Reports Archive

Since the Weekly Volcanic Activity Report began in November 2000, there have been 20,019 individual reports over 1,216 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
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 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 Kilauea
Seismicity abruptly increased below Kilauea’s summit at about 1400 on 29 September. Around 30 minutes later the earthquakes became more intense, frequent, and shallower, and deformation patterns rapidly changed. The data suggested an upward movement of magma that prompted HVO to raise the Aviation Color Code to Orange and the Volcano Alert Level to Watch at 1509. A new eruption was identified at 1521 when incandescence from Halema`uma`u Crater became visible in webcam views; HVO raised the Aviation Color Code to Red and the Volcano Alert Level to Warning. Fissures opened along the bottom of Halema`uma`u Crater floor and produced lava fountains and flows. A photo taken at 1615 showed a large plume comprised of steam, carbon dioxide, and sulfur dioxide rising from the fissures. Measurements just after the eruption started showed sulfur dioxide emissions of around 85,000 tonnes/day. At about 1640 another fissure with several vents opened on the inner W wall of the crater and produced low lava fountains and flows that descended to the crater floor. The vent expanded by 1709. Lava from both fissures pooled on the solidified lava lake surface and quickly began to overturn and create a lava lake. Tephra was deposited in areas SW of the crater and collected by HVO scientists for analysis.

The tallest lava fountain was near the S end of the lava lake and rose 20-25 m during the night of 29-30 September. During a helicopter overflight around 0730 on 30 September scientists determined that the lake was about 980 m E-W and 710 m N-S, covering an estimated 52 hectares. The W wall vent was visible, and several fountains were rising from the fissure in the central part of the lake. Sulfur dioxide emission rates remained high, estimated at around 20,000 tonnes/day. Overnight during 30 September-1 October fountains rose as high as 15 m at the dominant vent in the W wall. Less vigorous fountaining persisted at other vents, though fewer were active. The lake had risen 24 m by the morning of 1 October, adding 4 m in the past day. Cooled and crusted parts of the lake’s surface overturned, or “foundered.” Sulfur dioxide emission rates remained high, estimated at around 12,900 tonnes per day.

The lake had risen another 2 m by the morning of 2 October; fountains were 7 m tall at the main W wall vent and 1-2 m at the southern vents. Fountains occasionally rose as high as 50-60 m in bursts. Pumice, Pele?s hair, and fragments of volcanic glass were deposited downwind. The sulfur dioxide emission rate on 3 October was again high at 14,750 tonnes/day. The W vent was again the most vigorous during 3-4 October with sustained lava fountains to 10-15 m with occasional bursts up to 20 m. The lake rose 3 m, past the base of the W vent where a 12-m-high spatter cone had formed, and continued to founder in spots. Lava fountains rose 5-10 m from the vents in the S and central portions of the lake, including along a fissure 35-42 m long, with occasional larger bursts. The lake was not level and generally higher near the location of the vents; the W end was 1-2 m higher than the E, and S end was about 1 m higher than the N. By 4 October ledges about 20 m wide separated the N and E parts of the active lava lake from the crater wall and were lower than the lake surface; the N, E, and S margins of the lake were perched about 3 m above the surrounding ledge. The sulfur dioxide emission rate remained elevated but had decreased to 7,000-9,000 tonnes/day. HVO lowered the Aviation Color Code to Orange and the Volcano Alert Level to Watch at 1652. On 5 October lava fountaining from the W vent was unchanged while fountains from the other vents rose 1-5 m. The lake rose 1 more meter.
Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
Report for La Palma
The eruption at La Palma continued during 29 September-5 October, characterized by Strombolian explosions, lava fountaining from multiple vents, lava flows, and daily ash emissions. Seismicity continued to be elevated with earthquakes located mainly 10-15 km deep (though some were 25-40 km deep) in the same area where the swarm first began on 11 September; dozens of events were felt by residents.

Within the first eight days of the eruption, 21-27 September, an estimated 50 million cubic meters of material had been erupted. Just before midnight on 28 September the lava reached the ocean, producing a steam-and-gas plume; within 45 minutes the lava created a 50-m-high delta. The sulfur dioxide flux was as high as 16,760 tons per day. On 29 September the PEVOLCA (Plan de Emergencias Volcánicas de Canarias) steering committee restated that the 2.5 km and maritime exclusion zones around the vents and ocean entry, respectively, remained in effect; residents were periodically allowed to collect belongings and care for animals and crops. The lava covered almost 4.8 square kilometers, burying or damaging 744 buildings. There were 185 evacuees in a local hotel. Ash plumes continued to rise from the active vents, and IGN noted a decrease in plume altitude to 3.5 km (11,500 ft) a.s.l. on 29 September and then a rise to 5 km (16,400 ft) a.s.l. the next day.

Lava continued flowing to the sea along the same path. The lava delta had grown three times in size by 30 September to an estimated 0.17 square kilometers; the furthest edge of the delta was 450 m from the coast, it had spread laterally 600-800 m, and was as thick as 24 m. PEVOLCA lifted access restrictions for residents of Tazacorte, San Borondón, Marina Alta, Marina Baja, and La Condesa (nearly 4,000 people); they had previously been warned to stay indoors to minimize coming into contact with potentially toxic gas plumes generated from the ocean entry. Restrictions for other residents living near the margins of the flows were also lifted.

Two vents opened about 600 m NW of the main cone on 1 October and within two days had formed small cones. Lava from the vents traveled W and joined the main flow field downslope. The lava delta had extended 540 m from the coastline. Ash plumes rose to 3-5 km a.s.l. and drifted S on 2 October, and sulfur dioxide emissions were 3,401 tons per day.

By 3 October an estimated 946 houses had been completely demolished and 128 had been partially damaged. The width of the flow field was a maximum of 1,250 m and lava tubes were identified in satellite images. The lava delta had developed four lobes being fed by multiple flows and had an estimated area of 0.32 square kilometers. In the afternoon the frequency and intensity of explosive activity increased and bombs were ejected as far as 800 m. Lava fountains rose hundreds of meters and ash plumes rose as high as 4.5 km (14,800 ft) a.s.l. The sulfur dioxide emission rate reached 16,000 tons per day. During 1900-1945 one of the new cones collapsed, which allowed the inner lava lake to spill out, sending flows downslope carrying blocks from the destroyed portion of the cone. Ash plumes rose as high as 4.5 km a.s.l. and explosions ejected bombs on 5 October according to a news report. Some explosions produced dense black plumes that billowed as they rose above the vent. The Alert Level remained at Red (the highest level on a four-color scale) for affected communities.
Sources: Instituto Volcanológico de Canarias (INVOLCAN), Instituto Geográfico Nacional (IGN), EL PAÍS, EL PAÍS, EL PAÍS, EL PAÍS, EL PAÍS, Jorge Eduardo Romero Moyano (University of Manchester), Gobierno de Canaries, 1-1-2 Canarias
Report for Nyiragongo
According to a news article the scientific director of GVO stated that lava had returned to Nyiragongo's crater on 18 September. Notable thermal anomalies were visible in Sentinel satellite images on 29 September and 4 October.
Sources: Observatoire Volcanologique de Goma (OVG), Agence France-Presse (AFP)
Report for Vulcano
INGV reported that hydrothermal activity at Vulcano increased in July, and notably more in September. Specifically, temperatures of the fumaroles on the crater rim and on the inner flank had increased along with the amounts of carbon dioxide and sulfur dioxide in the emissions. The highest temperature of 340 degrees Celsius was along the rim. The temperature and salinity of groundwater measured near the base of La Fossa cone were both elevated, and outgassing from ground sites was noted. On 13 September the seismic network detected a significant increase in microseismcity linked to hydrothermal processes. Additionally, very-long-period events were also recorded for the first time in 15 years when instrumentation able to detect the signals was installed. Deformation on the N side of the cone was first identified in mid-August and totaled 1 cm of uplift by mid-September. The report stated that new seismic stations and instruments to measure carbon dioxide emissions had been added to the monitoring network, and a thermal camera pointing at the fumarolic field was planned. The Dipartimento della Protezione Civile raised the Alert Level to Yellow (the second lowest level on a four-color scale) on 1 October.
Sources: Sezione di Catania - Osservatorio Etneo (INGV), Dipartimento della Protezione Civile
Report for Aira
JMA reported that incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible at night during 27 September-4 October. The trend of inflation that was first detected on 13 September continued. The sulfur dioxide emission rate was 1,500 tons per day on 28 September. A very small eruptive event occurred on 3 October. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.
Source: Japan Meteorological Agency (JMA)
Report for Fagradalsfjall
The Institute of Earth Sciences reported that lava effusion at Krýsuvík-Trölladyngja volcanic system, close to Fagradalsfjall on the Reykjanes Peninsula, likely ceased during the evening of 18 September. The area of the flow field was about 4.85 square kilometers, and the total volume erupted was 150 million cubic meters, based on 30 September measurements. Parts of lava flows thickened in areas to the S of Geldingadalur and in Nàtthagi valley, and deflated in areas N of Geldingadalur. Points of incandescence were visible at night, at least through 4 October, likely from lava flows that continued to advance downslope.

A seismic swarm in an area SW of Keilir (about 10 km NE of the fifth vent), at the N end of the dike intrusion, began on 27 September. According to news reports, over 6,000 earthquakes at depths of 5-6 km had been recorded by 4 October with at least 12 of them over M 3; the largest event was a M 3.8. Some of the larger events were felt in the capital. The seismicity was similar to patterns recorded before the beginning of the eruption to the SW. IMO stated that more data was needed to characterize the data as either indicative of magma movement or due to tectonic stress. The Aviation Color Code remained at Orange due to the lack of ash and tephra emissions, though IMO warned of the potential for lapilli and scoria fallout within a 650 m radius of the active vent. Authorities also warned of gas emission hazards.
Sources: Icelandic Meteorological Office (IMO), Icelandic National Broadcasting Service (RUV), Icelandic National Broadcasting Service (RUV), Almannavarnadeild ríkislögreglustjóra (National Commissioner of the Icelandic Police and Department of Civil Protection and Emergency Management)
Report for Great Sitkin
AVO reported that lava effusion continued at Great Sitkin during 29 September-5 October. Seismicity remained elevated and was characterized by small earthquakes consistent with lava effusion. Elevated surface temperatures were detected in satellite images. By 3 October the dome had grown to 1,200 m E-W and 1,000 m N-S. Lava flows that continued to advance down the S and SW flanks were about 300-350 m long. The SW lobe was descending two drainages and produced hot avalanches that traveled 450 m downslope on top of a snow field. The Aviation Color Code and the Volcano Alert Level remained at Orange and Watch, respectively.
Source: US Geological Survey Alaska Volcano Observatory (AVO)
Report for Karymsky
KVERT reported that a thermal anomaly over Karymsky was identified in satellite images during 24-28 September. Ash plumes rose as high as 4.6 km (15,100 ft) a.s.l. and drifted 100 km E, SE, and SW during 24-26 September. 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 Katmai
AVO reported that beginning at 0400 on 2 October strong winds in the vicinity of Katmai and the Valley of Ten Thousand Smokes blew unconsolidated ash SE towards Kodiak Island at an altitude up to 1.8 km (6,000 ft) a.s.l. The ash was originally deposited during the Novarupta eruption in 1912. The Volcano Alert Level remained at Normal and the Aviation Color Code remained at Green.
Source: US Geological Survey Alaska Volcano Observatory (AVO)
Report for Klyuchevskoy
On 29 September strong winds resuspended unconsolidated ash from Klyuchevskoy’s flanks causing KVERT to raise the Aviation Color Code to Orange (the second highest level on a four-color scale). Conditions were quiet the next day; KVERT lowered the Aviation Color Code back to Green.
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Report for Langila
The Darwin VAAC reported that a discrete ash plume from Langila rose to 1.8 km (6,000 ft) a.s.l. on 3 October and drifted S. A thermal anomaly was visible afterward. On 4 October an ash plume again rose to 1.8 km a.s.l. and drifted S.
Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Report for Lewotolok
PVMBG reported that the eruption at Lewotolok continued during 28 September-4 October. White-and-gray plumes rose as high as 800 m above the summit and drifted NW, W, and SW. Rumbling sounds were reported almost daily. During 30 September-1 October and 3-4 October incandescent material was ejected as far as 700 m away from the vent in multiple directions. The Alert Level remained at 3 (on a scale of 1-4) and the public was warned to stay 3 km away from the summit crater.
Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
Report for Merapi
BPPTKG reported minor morphological changes to Merapi’s SW lava dome, located just below the SW rim and in the summit crater, and no changes to the summit crater dome during 24-30 September. The SW dome grew 1 m taller and had an estimated volume of 1.63 million cubic meters; the summit lava dome had an estimated volume of 2.85 million cubic meters. As many as 67 lava avalanches traveled a maximum of 1.8 km SW. The Alert Level remained at 3 (on a scale of 1-4), and the public was warned to stay 3-5 km away from the summit based on location.
Source: Balai Penyelidikan dan Pengembangan Teknologi Kebencanaan Geologi (BPPTKG)
Report for Pavlof
AVO reported that seismicity at Pavlof remained elevated during 29 September-5 October. No explosions were recorded most days by the seismic and infrasound networks, and no eruptive activity was observed in mostly cloudy webcam and satellite images. On 3 October webcam images showed that recent ash deposits on the flanks had been covered by fresh snow; later that night either new ash deposits were visible in webcam images or older deposits were revealed due to snowmelt. Weakly elevated surface temperatures were identified in satellite images. At least two minor explosions were recorded during 4-5 October and minor emissions likely comprised of steam and sulfur dioxide were visible in morning webcam images on 5 October. The Volcano Alert Level and Aviation Color Code remained at Watch and Orange, respectively.
Source: US Geological Survey Alaska Volcano Observatory (AVO)
Report for Reventador
IG reported that a high level of activity continued to be recorded at Reventador during 29 September-3 October; cloudy weather conditions sometimes prevented webcam and satellite views. Gas-and-ash plumes, often observed multiple times a day with the webcam or reported by the Washington VAAC, rose as high as 1 km above the summit crater and drifted mainly W and NW. Crater incandescence was often observed at night along with incandescent blocks that rolled as far as 800 m down the flanks.
Source: Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN)
Report for Sangay
IG reported a high level of activity at Sangay during 28 September-5 October. Weather clouds and rain sometimes prevented visual and webcam observations of the volcano. Ash plumes were identified in satellite images by the Washington VAAC or in webcam views during 30 September-1 October and 3 and 5 October; plumes rose 500-1,200 m above the volcano and drifted W and SW. Thermal anomalies over the volcano were often visible in satellite data. An active lava flow on the flanks was visible during a break in the weather cloud cover the evening of 4 October.
Source: Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN)
Report for Semisopochnoi
AVO reported that eruptive activity at Semisopochnoi's North Cerberus crater continued during 29 September-5 October. Seismicity remained elevated with intermittent explosion signals or bursts of activity likely from explosions. A few explosions were also detected in regional infrasound data during 2-5 October. Small ash clouds were observed almost daily in either webcam or satellite images rising to altitudes below 3 km (10,000 ft) a.s.l.; plumes drifted ENE on 2 October, then N and NW on 3 October. Sulfur dioxide plumes were possibly observed on a few days, though definitely on 3 October. Webcams located 5-6 km from the active vent recorded ashfall during 4-5 October. 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 Sheveluch
KVERT reported that a thermal anomaly over Sheveluch was identified in satellite images during 24 September-1 October. 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 Suwanosejima
JMA reported that 129 explosions at Suwanosejima's Ontake Crater produced eruption plumes that rose as high as 3 km above the crater rim during 27 September-4 October. Large volcanic bombs were ejected as far as1 km from the crater. Crater incandescence was visible nightly. The Alert Level remained at 3 and the public was warned to stay 2 km away from the crater.
Source: Japan Meteorological Agency (JMA)
Report for Taal
PHIVOLCS reported that sulfur dioxide emissions at Taal averaged 8,854 tonnes/day beginning on 27 September, and peaked on 5 October at 25,456 tonnes/day which was the highest ever sulfur dioxide gas flux recorded at the volcano. On 27 September the number of daily volcanic earthquakes significantly decreased. During 27 September-5 October upwelling of hot volcanic fluids in the lake was visible and gas-and-steam plumes rose as high as 3 km above the lake. The report noted that a sudden increase in inflation below Taal Volcano Island was recorded in August. The Volcano Alert Level remained at a 2 (on a scale of 0-5). PHIVOLCS reminded the public that the entire Taal Volcano Island is a Permanent Danger Zone (PDZ) and that boating on Taal Lake was prohibited.
Source: Philippine Institute of Volcanology and Seismology (PHIVOLCS)
Report for Telica
INETER reported that on 4 September a diffuse ash plume from Telica rose 1.2 km (4,000 ft) a.s.l. and drifted less than 10 km WSW, based on satellite images and model data.
Source: Instituto Nicaragüense de Estudios Territoriales (INETER)
Report for Yasur
On 30 September the Vanuatu Meteorology and Geo-Hazards Department (VMGD) reported that seismic data and recent visual observations at Yasur confirmed ongoing explosions and gas-and-ash emissions. A few earthquakes were recorded on 28 September. The Alert Level remained at 2 (on a scale of 0-4). VMGD reminded residents and tourists that hazardous areas were near and around the volcanic crater, within a 600-m-radius exclusion zone, and that volcanic ash and gas could reach areas impacted by trade winds.
Source: Vanuatu Meteorology and Geohazards Department (VMGD)