All times are local unless otherwise stated.

Ketoi (Russia) | 19 September-25 September 2018 | New Activity / Unrest Cite this Report
Ketoi Kuril Volcanic Arc	Based on a report from SVERT the Tokyo VAAC reported that on 21 September an ash plume from Ketoi drifted NE. Source: Tokyo Volcanic Ash Advisory Center (VAAC)
Piton de la Fournaise (France) | 19 September-25 September 2018 | New Activity / Unrest Cite this Report
Piton de la Fournaise Reunion Hotspot Volcano Group	OVPF reported that, based on visual observations and satellite data, a lava flow at Piton de la Fournaise had traveled 2.8 km S and then SE, and was 500 m from the S wall of Enclos Fouqué by 18 September. It was 660 m wide at the widest part. Volcanic tremor was at a low level and relatively stable on 19 September, and then decreased on 20 September. During fieldwork on 21 September volcanologists observed three active lava fountains that were continuing to build the cone. The E wall was 30 m high, particularly vertical, and appeared unstable with numerous fractures. The lava flows were well-channeled and had advanced several hundred meters since 19 September, threatening an OVPF seismic station. Volcanic tremor levels fluctuated during 21-22 September. Deposits of Pele’s hair were noted in the Grand Coude area (8-10 km SW) on 22 September. During an overflight that same day volcanologists noted that the three lava fountains in the cone were visible, and lava tubes had formed near the uppermost part of the channel. Volcanic tremor had doubled in intensity on 23 September. Compared to the beginning of the eruption on 15 September the sulfur dioxide emissions had decreased by a factor of six; gas plumes were small and drifted S and W, but were confined to the Enclos Fouqué. Source: Observatoire Volcanologique du Piton de la Fournaise (OVPF)
Sarychev Peak (Russia) | 19 September-25 September 2018 | New Activity / Unrest Cite this Report
Sarychev Peak Kuril Volcanic Arc	KVERT reported a continuing eruption at Sarychev Peak (the NW part of Mantua Island) through 21 September. Island observers reported explosions at 1010 on 18 September that sent ash plumes to 4.5 km (14,800 ft) a.s.l. Ash plumes identified in satellite images during 17-18 September drifted 265 km E. The Aviation Color Code remained at Orange. Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Semisopochnoi (United States) | 19 September-25 September 2018 | New Activity / Unrest Cite this Report
Semisopochnoi Aleutian Ridge Volcanic Arc	AVO reported that during 19-25 September seismicity at Semisopochnoi remained elevated, alternating between periods of continuous and intermittent bursts of tremor. Tremor bursts at 1319 on 21 September and at 1034 on 22 September produced airwaves detected on a regional infrasound array on Adak Island; no ash emissions were identified above the low cloud deck in satellite data, and the infrasound detections likely reflected an atmospheric change instead of volcanic activity. The Aviation Color Code (ACC) remained at Yellow and Volcano Alert Level (VAL) remained at Advisory. Source: US Geological Survey Alaska Volcano Observatory (AVO)
Ulawun (Papua New Guinea) | 19 September-25 September 2018 | New Activity / Unrest Cite this Report
Ulawun Bismarck Volcanic Arc	According to the Darwin VAAC, a pilot observed an ash plume from Ulawun on 21 September rising to an altitude of 3.7 km (12,000 ft) a.s.l. and drifting W. Ash was not confirmed in satellite images, though weather clouds obscured views. Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Veniaminof (United States) | 19 September-25 September 2018 | New Activity / Unrest Cite this Report
Veniaminof Aleutian Ridge Volcanic Arc	AVO reported that the eruption at Veniaminof continued during 19-25 September, as evidenced by nighttime incandescence recorded by the FAA web camera in Perryville (35 km S), elevated surface temperatures in thermal satellite data, and elevated seismic activity. A gas plume was occasionally visible during clear daytime conditions. A lava flow had traveled 800 m down the S flank of the summit cone by 14 September, though satellite images from 18 September indicated no further advancement. The Aviation Color Code remained at Orange and the Volcano Alert Level remained at Watch. Source: US Geological Survey Alaska Volcano Observatory (AVO)

Aira (Japan) | 19 September-25 September 2018 | Continuing ActivityCite this Report
Aira Ryukyu Volcanic Arc	JMA reported that there were eight events and an additional five explosions at Minamidake crater (at Aira Caldera’s Sakurajima volcano) during 18-25 September, with ash plumes rising as high as 2.1 km above the crater rim and material ejected as far as 1.1 km. Crater incandescence was occasionally visible at night. The Alert Level remained at 3 (on a 5-level scale). Source: Japan Meteorological Agency (JMA)
Ambae (Vanuatu) | 19 September-25 September 2018 | Continuing ActivityCite this Report
Ambae Vanuatu Volcanic Arc	On 21 September the Vanuatu Meteorology and Geo-hazards Department reported that during September activity at Ambae’s Lake Voui was characterized only by steam emissions; the eruption had ceased. The Alert Level was lowered to 2 (on a scale of 0-5). Source: Vanuatu Meteorology and Geohazards Department (VMGD)
Dukono (Indonesia) | 19 September-25 September 2018 | Continuing ActivityCite this Report
Dukono Halmahera Volcanic Arc	Based on satellite data, wind model data, and notices from PVMBG, the Darwin VAAC reported that during 19-25 September ash plumes from Dukono rose to an altitude of 1.8 km (6,000 ft) a.s.l. and drifted in multiple directions. Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Ebeko (Russia) | 19 September-25 September 2018 | Continuing ActivityCite this Report
Ebeko Kuril Volcanic Arc	Volcanologists in Severo-Kurilsk (Paramushir Island), about 7 km E of Ebeko, observed explosions during 14-21 September that sent ash plumes to 4.2 km (13,800 ft) a.s.l. A thermal anomaly over the volcano was occasionally visible in satellite data, and an ash plume was identified drifting about 80 km E on 14 September. The Aviation Color Code remained at Orange (the second highest level on a four-color scale). Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Fuego (Guatemala) | 19 September-25 September 2018 | Continuing ActivityCite this Report
Fuego Central America Volcanic Arc	INSIVUMEH reported that during 20-21 and 24-25 September explosions at Fuego generated ash plumes that rose almost as high as 1 km above the crater and drifted 12 km W and SW. Incandescent material was ejected 150 m above the crater rim, and caused avalanches of material within the crater area. Ashfall was reported in areas downwind including Sangre de Cristo (8 km WSW), Finca Palo Verde, Panimaché (8 km SW), and San Pedro Yepocapa (8 km NW). On 25 September hot, steaming lahars descended the El Jute (SE) and Las Lajas (SE) drainages, carrying blocks up to 2 m in diameter, and branches and tree trunks. Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Karymsky (Russia) | 19 September-25 September 2018 | Continuing ActivityCite this Report
Karymsky Eastern Kamchatka Volcanic Arc	KVERT reported that a thermal anomaly over Karymsky was identified in satellite images on 19 September; the volcano was obscured by weather clouds the rest of the days during 14-21 September. The Aviation Color Code remained at Orange (the second highest level on a four-color scale). Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Kilauea (United States) | 19 September-25 September 2018 | Continuing ActivityCite this Report
Kilauea Hawaiian-Emperor Hotspot Volcano Group	HVO reported no incandescence from a collapse pit in the central part of Kilauea’s Fissure 8 cone during 19-25 September, though a small amount of fuming was visible during the day. Seismicity and ground deformation remain low at the summit, and small aftershocks from the M 6.9 earthquake in early May were located along faults on the south flank. The combined rate of sulfur dioxide emission from the summit and the LERZ (less than 1,000 tonnes/day) were lower than any time since late 2007. The Volcano Alert Level remained at Watch and the Aviation Color Code remained at Orange. Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
Krakatau (Indonesia) | 19 September-25 September 2018 | Continuing ActivityCite this Report
Krakatau Sunda Volcanic Arc	Based on satellite data, wind model data, and notices from PVMBG, the Darwin VAAC reported that during 18-24 September ash plumes from Anak Krakatau rose to altitudes of 0.9-3.7 km (3,000-12,000 ft) a.s.l. and drifted in multiple directions. The Alert Level remained at 2 (on a scale of 1-4); residents and visitors were warned not to approach the volcano within 2 km of the crater. Sources: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM), Darwin Volcanic Ash Advisory Centre (VAAC)
Manam (Papua New Guinea) | 19 September-25 September 2018 | Continuing ActivityCite this Report
Manam Bismarck Volcanic Arc	Based on analyses of satellite imagery and model data, the Darwin VAAC reported that at 2050 on 23 September a short-lived eruption at Manam produced an ash plume that rose 8.5 km (28,000 ft) a.s.l. and drifted NW. Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Merapi (Indonesia) | 19 September-25 September 2018 | Continuing ActivityCite this Report
Merapi Sunda Volcanic Arc	PVMBG reported that during 17-23 September the new lava dome in Merapi’s summit crater continued to slowly grow. By 22 September the volume of the lava dome was an estimated 113,000 cubic meters, and the growth rate was 3,000 cubic meters per day. White emissions of variable density rose 100 m above the summit. The Alert Level remained at 2 (on a scale of 1-4), and resident were warned to remain outside of the 3-km exclusion zone. Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
Pacaya (Guatemala) | 19 September-25 September 2018 | Continuing ActivityCite this Report
Pacaya Central America Volcanic Arc	INSIVUMEH reported that during 17-18, 20-21, and 24-25 September Strombolian explosions at Pacaya’s Mackenney Crater ejected material as high as 25 m above the crater rim. As many as four lava flows originating from Mackenney Crater traveled 50-250 m NW. Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Sabancaya (Peru) | 19 September-25 September 2018 | Continuing ActivityCite this Report
Sabancaya Central Andean Volcanic Arc	Observatorio Vulcanológico del Sur del IGP (OVS-IGP) and Observatorio Vulcanológico del INGEMMET (OVI) reported that explosions at Sabancaya averaged 16 per day during 17-23 September. Hybrid earthquakes were infrequent and of low magnitude. Gas-and-ash plumes rose as high as 3.5 km above the crater rim and drifted 40 km N, NE, and SE. The MIROVA system detected eight thermal anomalies, and on 17 September the sulfur dioxide gas flux was high at 1,600 tons/day. The report noted that the public should not approach the crater within a 12-km radius. Sources: Instituto Geológico Minero y Metalúrgico (INGEMMET), Instituto Geofísico del Perú (IGP)
Sangay (Ecuador) | 19 September-25 September 2018 | Continuing ActivityCite this Report
Sangay Northern Andean Volcanic Arc	Based on satellite images and wind model data, the Washington VAAC reported that during 19-20 September ash emissions from Sangay rose to 5.8-6.1 km (19,000-20,000 ft) a.s.l., drifted WNW and W, and became diffuse after 37 km. Source: Washington Volcanic Ash Advisory Center (VAAC)
Santa Maria (Guatemala) | 19 September-25 September 2018 | Continuing ActivityCite this Report
Santa Maria Central America Volcanic Arc	INSIVUMEH reported that heavy rain at Santa María on 20 September produced hot lahars in the San Isidro-Tambor River (S), a tributary of Salamá River. The lahars were 25 m wide, 2 m deep, had a sulfur odor, and carried branches, tree trunks, and blocks up to 2 m in diameter. Lahars also descended the Nimá I (S) drainage. On 21 September explosions generated ash plumes that rose 800 m above the crater rim and drifted W and SW; minor amounts of ash fell locally. Lahars descended the Nimá I, Salamá, and San Isidro drainages. During 24-25 September explosions produced ash plumes that rose 500-700 m and drifted SW. Avalanches of material traveled down the SE and NE flanks. Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Semeru (Indonesia) | 19 September-25 September 2018 | Continuing ActivityCite this Report
Semeru Sunda Volcanic Arc	Based on analysis of satellite images, the Darwin VAAC reported that on 19 September a possible ash-and-steam plume from Semeru rose to an altitude of 4 km (13,000 ft) a.s.l. and drifted SSW. Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Sheveluch (Russia) | 19 September-25 September 2018 | Continuing ActivityCite this Report
Sheveluch Eastern Kamchatka Volcanic Arc	KVERT reported that a thermal anomaly over Sheveluch was identified in satellite data during 14, 16-17, and 19-20 September. The Aviation Color Code remained at Orange (the second highest level on a four-color scale). Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

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.

Use the dropdowns to choose the year and week for archived Weekly Reports.

 News Feeds and Google Placemarks

 Criteria & Disclaimers

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.

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.

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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)