All times are local unless otherwise stated.

Axial Seamount | 29 April-5 May 2015 | New Activity / Unrest Cite this Report
Axial Seamount Juan de Fuca Ridge	Geologists reported that starting at 2230 on 23 April thousands of small earthquakes were detected at the Axial Seamount, and then the seafloor dropped by 2.4 m over a three-day period. It was unclear if the earthquakes and deflation meant an eruption or a large intrusion of magma that did not reach the surface. Source: Oregon State University's Marine Science Center and NOAA/PMEL EOI Program
Bulusan | 29 April-5 May 2015 | New Activity / Unrest Cite this Report
Bulusan Luzon (Philippines)	PHIVOLCS reported that at 0809 on 1 May a steam-and-ash explosion from Bulusan was detected for five minutes by the seismic network. Dense rain clouds at the summit prevented visual observations at the time, but during a clear period around 1030 gray-white steam plumes were observed rising 200 m above the NW vent and drifting WNW. Minor ashfall affected areas to the W and NW, including Bolos, Cogon, Gulang-Gulang, Sangkayon, Tinampo, and Umagom in Irosin, Sorsogon, and Puting Sapa in Juban, Sorsogon. Only five volcanic earthquakes had been recorded during the past week prior to the event; after the event the network detected 62 volcanic earthquakes within an eight-hour period. Alert Level 0 and the 4-km restricted zone, the Permanent Danger Zone (PDZ), were maintained due to the possibility of sudden and hazardous steam-driven or phreatic eruptions. Source: Philippine Institute of Volcanology and Seismology (PHIVOLCS)
Calbuco | 29 April-5 May 2015 | New Activity / Unrest Cite this Report
Calbuco Southern Chile	OVDAS-SERNAGEOMIN reported that on 29 April a weak ash plume rose as high as 1.5 km above Calbuco and seismicity remained stable. An event that began at 1308 on 30 April produced an ash plume that rose 3-5 km and drifted SE. A small lahar in the Blanco River may have been caused by a pyroclastic flow. Tremor amplitude increased and became sustained after the event. On 2 May the number of earthquakes increased. Seismicity significantly increased on 3 May, characterized by a swarm of volcano-tectonic events, and then decreased afterwards. Seismicity was low and stable on 5 May. A plume rose less than 1 km during 1-3 May; cloud cover prevented visual observations of the volcano during 4-5 May. According to ONEMI, the number of evacuees totaled 6,685 on 5 May. The Alert Level remained at Red (the highest level on a four-color scale). Sources: Servicio Nacional de Geología y Minería (SERNAGEOMIN), Oficina Nacional de Emergencia-Ministerio del Interior (ONEMI)
Dempo | 29 April-5 May 2015 | New Activity / Unrest Cite this Report
Dempo Southeastern Sumatra	Observers at the PVMBG Dempo observation post reported that during 0730-0900 on 27 April diffuse gray-white plumes rose 50 m above Dempo crater. Seismicity had increased during April as compared to the previous month. On 29 April the Alert Level was raised to 2 (on a scale from 1-4). Visitors and residents were advised not to go within a 1-km radius of the summit. Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
Karangetang | 29 April-5 May 2015 | New Activity / Unrest Cite this Report
Karangetang Sangihe Islands	Based on observations conducted at the Karangetang Volcano Observation Post in the village of Salili, PVMBG reported that white plumes rose as high as 350 m above Karangetang's main crater and 25 m above Crater II during 22-29 April. Incandescence from the lava dome was observed at night. Lava flows began to appear on 22 April; incandescent avalanches from the fronts of 150-m-long lava flows traveled as far as 2 km towards Batuawang and Kahetang drainages (E) during 22-29 April. On 26 April pyroclastic flows traveled 2.2 km towards Kahetang drainage. On 28 April explosions produced plumes and ejected incandescent material 50 m high. The Alert Level remained at 3 (on a scale of 1-4); visitors and residents were warned not to climb Karangetang any higher than 500 a.s.l. Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
Kilauea | 29 April-5 May 2015 | New Activity / Unrest Cite this Report
Kilauea Hawaiian Islands (USA)	In a special statement on 29 April, HVO reported that beginning at 2140 the night before the lava lake in Kilauea’s Halema'uma'u Crater overflowed it's rim multiple times, sending lobate sheets of pahoehoe as far as 130 m across the crater floor. The report also noted that a few explosions in the lake triggered by falling wall rock had occurred; one at 1020 on 28 April ejected boulders of molten spatter (2 m in diameter) onto the rim of Halema'uma'u Crater, in the vicinity of the closed visitor overlook fence. Spatter also blanketed an area 100 m along the rim and 50 m back. This area had been closed to the public since 2007. The accumulating lava had built up a rim around the lake that was a few meters above the crater floor. On 30 April the lava-lake surface was about 4 m below the new rim. During 1-2 May the lake level was near or at the rim, and overflowed onto the floor several times. During 2-3 May the lake surface was 3-5 m above the original, pre-flow crater floor. A collapse of a portion of the crater wall at 1320 on 3 May impacted the lake and triggered a small explosion, ejecting fist-sized clasts onto the crater rim. Lava overflowed the rim several times during 4-5 May. During 29 April-5 May Kilauea’s 27 June NE-trending lava flow continued to be active with three areas of breakouts within and along the flow-field margins, within 8 km of Pu'u 'O'o. The three main areas of breakouts were the 21 February breakout on the flank of Pu'u 'O'o, the 9 March breakout near the forested cone of Kahauale'a, and a relatively small forked breakout 5-6 km farther NE of Pu'u 'O'o. Forest burned about 8 km NE of the crater. Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
Tungurahua | 29 April-5 May 2015 | New Activity / Unrest Cite this Report
Tungurahua Ecuador	IG reported moderate activity at Tungurahua on 29 April, and low levels during 30 April-5 May. Minor steam plumes were visible most days even though inclement weather often obscured views of the crater area. Source: Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN)
Ubinas | 29 April-5 May 2015 | New Activity / Unrest Cite this Report
Ubinas Peru	Instituto Geofísico del Perú (IGP) Observatorio Volcanológico del Sur (OVS) reported that during 29 April-5 May long-period and tornillo-type earthquakes continued to decrease while volcano-tectonic events increased. Hybrid events were at a low level, however, an increase in the number of events were detected on 29 April. Overall the dominant signal was spasmodic tremor associated with ash-and-steam emissions. Constant steam emissions were visually observed even though cloud cover often prevented observations. Ash emission increased on 1 May, rising as high as 800 m above the crater. Source: Instituto Geofísico del Perú (IGP)

Aira | 29 April-5 May 2015 | Continuing ActivityCite this Report
Aira Kyushu (Japan)	JMA reported that 12 explosions from Showa Crater at Aira Caldera’s Sakurajima volcano ejected tephra as far as 1,300 m during 27 April-1 May. Incandescence from the crater was visible at night. An explosion at 0720 on 27 April generated a large ash plume that rose 3.5 km above the crater. The next day an explosive eruption was detected by the seismic network for 40 minutes. A very small pyroclastic flow traveled 500 m down the SE flank of Showa Crater. The Alert Level remained at 3 (on a scale of 1-5). Based on JMA notices, the Tokyo VAAC reported that explosions during 29 April-5 May generated plumes which rose to altitudes of 1.8-3.4 km (6,000-11,000 ft) a.s.l. and drifted in multiple directions. Sources: Japan Meteorological Agency (JMA), Tokyo Volcanic Ash Advisory Center (VAAC)
Asosan | 29 April-5 May 2015 | Continuing ActivityCite this Report
Asosan Kyushu (Japan)	JMA reported that, based on seismic data, the eruption from Asosan’s Nakadake Crater that began on 25 November 2014 continued during 27 April-1 May. Ashfall was reported in areas to the SE and NE on 27 April. Field surveys were conducted on 27 April and 1 May; observers noted an off-white plume rising from the vent. A plume rose as high as 1.2 km above the crater rim on 29 April. The Alert Level remained at 2 (on a scale of 1-5). Source: Japan Meteorological Agency (JMA)
Chirinkotan | 29 April-5 May 2015 | Continuing ActivityCite this Report
Chirinkotan Kuril Islands (Russia)	SVERT reported that on 30 April a thermal anomaly over Chirinkotan was detected in satellite images. Cloud cover prevented views of the volcano on the other days during 27 April-4 May. The Aviation Color Code remained at Yellow. Source: Sakhalin Volcanic Eruption Response Team (SVERT)
Chirpoi | 29 April-5 May 2015 | Continuing ActivityCite this Report
Chirpoi Kuril Islands (Russia)	SVERT reported that satellite images over Snow, a volcano of Chirpoi, showed a thermal anomaly on 28 and 30 April, and 1 May. Cloud cover obscured views on other days during 27 April-4 May. The Aviation Color Code remained at Yellow. Source: Sakhalin Volcanic Eruption Response Team (SVERT)
Colima | 29 April-5 May 2015 | Continuing ActivityCite this Report
Colima Mexico	Based on satellite images, the Washington VAAC reported that on 30 April an ash plume from Colima drifted 30 km E before dissipating. Another ash plume drifted almost 20 km E. On 2 May an ash puff rose to an altitude of 4.3 km (14,000 ft) a.s.l. and drifted 150 km ENE to W. Another ash plume rose to an altitude of 6.7 km (22,000 ft) a.s.l. and drifted E. Later that day an ash plume drifted almost 85 km E before dissipating. Source: Washington Volcanic Ash Advisory Center (VAAC)
Dukono | 29 April-5 May 2015 | Continuing ActivityCite this Report
Dukono Halmahera	Based on analyses of satellite imagery and wind data, the Darwin VAAC reported that during 29 April-3 May ash plumes from Dukono rose to an altitude of 2.4-2.7 km (8,000-9,000 ft) a.s.l. and drifted 55-185 km E and SE. Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Karymsky | 29 April-5 May 2015 | Continuing ActivityCite this Report
Karymsky Eastern Kamchatka (Russia)	KVERT reported moderate activity at Karymsky during 17 April-1 May. Satellite images showed ash plumes drifting about 140 km NE on 27 April. The Aviation Color Code remained at Orange. Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Manam | 29 April-5 May 2015 | Continuing ActivityCite this Report
Manam Northeast of New Guinea	Based on observations of satellite imagery and wind data analyses, the Darwin VAAC reported that on 30 April an ash plume from Manam drifted 150 km NW at an altitude of 2.4 km (8,000 ft) a.s.l. Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Popocatepetl | 29 April-5 May 2015 | Continuing ActivityCite this Report
Popocatepetl Mexico	CENAPRED reported that during 8-14 April the seismic network recorded 13-77 gas and steam emissions, with another 204 emissions recorded over 1-2 May. Ash accompanied the emissions during 1-3 May. Gas-and-steam plumes were visible, although cloud cover mostly prevented observations. Nighttime crater incandescence was often noted. A series of explosions during 2218-2301 on 30 April ejected incandescent tephra 200 m onto the NE flank. Sequences of explosions were also detected during 0758-1356 on 1 May and during 0411-0935 on 2 May. Ashfall was reported in San Pedro Benito Juárez (10-12 km SE) in the municipality of Atlixco Puebla on 2 May. Explosions were also detected during 3-5 May. The Alert Level remained at Yellow, Phase Two. Source: Centro Nacional de Prevencion de Desastres (CENAPRED)
Ruapehu | 29 April-5 May 2015 | Continuing ActivityCite this Report
Ruapehu North Island (New Zealand)	GeoNet reported that water temperatures of Ruapehu's summit Crater Lake had been increasing since early December 2014, rising from 15 degrees Celsius to over 40 degrees in late January-early February. The temperatures declined to 31 degrees in mid-March, and then climbed again to 37-39 degrees. No other changes were detected at the lake. In addition, over the previous 2-3 weeks intermittent moderate-to-strong levels of volcanic tremor were detected, which had been some of the strongest recorded there over the past eight years. The report noted that historically there had not been a direct link between volcanic tremor and discrete volcanic eruptions or sequences of eruptions. The Aviation Colour Code remained at Green and the Volcanic Alert Level remained at 1 (signs of volcano unrest). Source: GeoNet
Sheveluch | 29 April-5 May 2015 | Continuing ActivityCite this Report
Sheveluch Central Kamchatka (Russia)	KVERT reported that during 24 April-1 May lava-dome extrusion onto Sheveluch’s N flank was accompanied by incandescence, hot block avalanches, and fumarolic activity. A daily thermal anomaly was also detected in satellite images. The Aviation Color Code remained at Orange. Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Shishaldin | 29 April-5 May 2015 | Continuing ActivityCite this Report
Shishaldin Fox Islands (USA)	AVO reported that seismicity at Shishaldin continued to be elevated over background levels 29 April-5 May indicating that low-level eruptive activity confined to the summit crater likely continued. Cloud cover frequently prevented satellite and webcam observations. Weakly elevated temperatures in the crater were detected on 4 May. The Aviation Color Code remained at Orange and the Volcano Alert Level remained at Watch. Source: US Geological Survey Alaska Volcano Observatory (AVO)
Turrialba | 29 April-5 May 2015 | Continuing ActivityCite this Report
Turrialba Costa Rica	OVSICORI-UNA reported that a 4-minute-long ash emission from Turrialba occurred at 0836 on 1 May. The ash plume rose about 500 m above the crater and drifted SW. Ash emissions that began at 1524 on 4 May lasted 23 minutes, and produced an ash plume that rose 2.5 km and drifted SW. The eruption ejected ballistics 1 km from the crater. Most of the ashfall occurred around the crater. Reports of minor ashfall and sulfur odors came from San José (Moravia, Coronado, Mata de Plátano, La Uruca, Guadalupe, Tibás, Calle Blancos, San Pedro Montes de Oca, Sabanilla Montes de Oca, Pavas, Zapote, Escazú, S of San José, Paso Ancho, Curridabat, Santa Ana), and a few localities in the eastern region of Heredia. On 5 May intermittent emissions of gas and ash rose 500 m; inclement weather prevented satellite observations. Source: Observatorio Vulcanologico y Sismologico de Costa Rica-Universidad Nacional (OVSICORI-UNA)
Villarrica | 29 April-5 May 2015 | Continuing ActivityCite this Report
Villarrica Central Chile	OVDAS-SERNAGEOMIN reported moderate seismic activity during 29 April-5 May. Nighttime crater incandescence and a thermal anomaly detected daily in satellite images suggested an active lava lake, with mild and periodic Strombolian activity. Gas emissions were visible in the daytime. The Alert Level remained at Orange (the second highest level on a four-color scale) and the public was warned to stay outside of a 5-km radius around the crater and away from drainages. Sources: Servicio Nacional de Geología y Minería (SERNAGEOMIN), Oficina Nacional de Emergencia-Ministerio del Interior (ONEMI)
Zhupanovsky | 29 April-5 May 2015 | Continuing ActivityCite this Report
Zhupanovsky Eastern Kamchatka (Russia)	KVERT reported that moderate activity continued at Zhupanovsky during 24 April-1 May. Satellite images detected a thermal anomaly over the volcano on 25 and 28 April. The Aviation Color Code remained at Orange. Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

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.

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.

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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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 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)