All times are local unless otherwise stated.

Ibu | 25 April-1 May 2018 | New Activity / Unrest Cite this Report
Ibu Halmahera	PVMBG reported that at 1822 on 30 April an eruption at Ibu generated a dark gray ash plume that rose at least 500 m above the crater rim and drifted E. The Alert Level remained at 2 (on a scale of 1-4), and the public was warned to stay at least 2 km away from the active crater, and 3.5 km away on the N side. Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
Karymsky | 25 April-1 May 2018 | New Activity / Unrest Cite this Report
Karymsky Eastern Kamchatka (Russia)	On 26 April KVERT reported that the last explosive event at Karymsky occurred on 27 January, and the last thermal anomaly was detected on 26 March; activity remained at a low level. The Aviation Color Code was lowered to Green (the lowest level on a four-color scale). Explosive activity was identified in satellite images beginning at 1825 on 28 April, prompting KVERT to raise the Alert Level to Orange. Ash plumes rose as high as 5.5 km (18,000 ft) a.s.l. and drifted 150 km NE. Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Kilauea | 25 April-1 May 2018 | New Activity / Unrest Cite this Report
Kilauea Hawaiian Islands (USA)	During 25 April-1 May HVO reported that the lava lake continued to rise, fall, and spatter in Kilauea’s Overlook crater. The lake level was high enough to produce lava flows onto the Halema'uma'u crater floor through 27 April, but afterwards fell to about 15-16 m below the new elevated rim. The lake level rose again, to just below the rim of the Overlook crater vent. Since 21 April about 2/3 of the crater floor had been covered by new lava flows. Episode 61g lava flows were active above Pulama pali, within 2 km of the active vent. A marked increase in seismicity and ground deformation at Pu'u 'O'o Crater was detected just after 1400 on 30 April, following weeks of uplift and increasing lava levels within the cone. Within a few minutes a webcam on the crater rim recorded the first of two crater floor collapses; the second collapse began at 1520 and lasted about an hour. Thought poor weather conditions inhibited views at times, a webcam recorded what were likely small explosions from the W side of the crater as the floor collapsed. At 1800 seismicity remained elevated, though ground deformation had significantly slowed. A large amount of red ash was produced from the collapses, and deposited around the crater as well as in areas up-rift as far as Mauna Ulu. Following the collapses of Pu'u 'O'o’s crater floor, seismicity and deformation increased along a large section of the East Rift Zone, in an area 9-16 km down-rift (with seismicity occurring as far E as highway 130), indicating an intrusion of magma. By 0830 on 1 May activity had significantly decreased. During an overflight that day a new, nearly continuous, 1-km-long crack was found on the W (up-rift) side of Pu'u 'O'o. The crack was steaming, and aligned in a segment with small pads of newly-erupted lava and spatter. Thermal images of Pu'u 'O'o Crater suggested that smaller drops of the crater floor likely continued on 1 May. Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
Kirishimayama | 25 April-1 May 2018 | New Activity / Unrest Cite this Report
Kirishimayama Kyushu (Japan)	JMA reported that a very small explosion at Iwo-yama (also called Ioyama, NW flank of Karakuni-dake), a stratovolcano of the Kirishimayama volcano group, occurred at 1815 on 26 April and produced a milky white plume that rose over 200 m. The event continued until around 1826. The event occurred from a fumarole in the vicinity of the highway, on the W side of Iwo-yama, first observed on 20 April. During a field survey on 30 April observers noted muddy water flowing as far as 500 m W. The Alert Level remained at 3 (on a scale of 1-5). Source: Japan Meteorological Agency (JMA)
Kusatsu-Shiranesan | 25 April-1 May 2018 | New Activity / Unrest Cite this Report
Kusatsu-Shiranesan Honshu (Japan)	JMA reported that on 21 April the number of volcanic earthquakes at Yugama crater (Kusatsu-Shiranesan complex) increased and deformation was also recorded. The Alert Level for the crater area was raised to 2 (on a 5-level scale) the next day. Deformation slowed on 23 April. Seismicity decreased on 23 April though continued to be somewhat elevated, and low-frequency events were recorded on 24 April. No surficial changes were noted during an overflight on 26 April. Source: Japan Meteorological Agency (JMA)
Marapi | 25 April-1 May 2018 | New Activity / Unrest Cite this Report
Marapi Central Sumatra	On 27 April a phreatic eruption at Marapi produced an ash plumes that rose 300 m above the crater rim. The Alert Level remained at 2 (on a scale of 1-4). Residents and visitors were advised not to enter an area within 3 km of the summit. Sources: Badan Nacional Penanggulangan Bencana (BNPB), Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
Piton de la Fournaise | 25 April-1 May 2018 | New Activity / Unrest Cite this Report
Piton de la Fournaise Reunion Island (France)	OVPF reported that seismicity at Piton de la Fournaise increased on 21 April, and then significantly on 23 April. A seismic crisis which began at 2015 on 27 April was accompanied by rapid deformation, indicating magma migrating towards the surface. The onset of tremor at 2350 heralded the beginning of the eruption, though the first visual confirmation of the eruption was recorded by the webcams at 0015 on 28 April. The eruption took place from fissures at Rivals Crater, and the SW flank of Dolomieu crater. During an overflight around 0830, scientists noted that four fissures had opened, one of which intersected the crater. Lava fountains less than 30 m high rose from the entire length of the fourth fissure, which was 300 m long and at a lower elevation that Rival Crater. Several small lava flows formed a larger flow which traveled 200-300 m S towards the Enclos Fouqué. Tremor steadily decreased throughout the day, and by the end of the day the lava flow had slowed in an area around 300 m away from the rampart. During 29-30 April tremor levels were relatively stable, with a few fluctuations related to morphological changes at the eruptive site such as cone building. During an overflight around 1020 on 30 April scientists observed three active vents (S of Rival Crater). The third vent, in a 5-m-high cone, was mostly closed over, though it continued to produced lava flows. The middle and most active cone was about 30-40 m long and 10-15 m high, and had a vent with a lava lake. Large bubbles of lava rose from the lake and exploded into lava fountains. Lava fountains from the northernmost vent rose no more than 15 m high. Lava flows had traveled 150 m and 1.2 km; the longer lava flow had reached the S rampart and traveled an additional 400 m E along it. Source: Observatoire Volcanologique du Piton de la Fournaise (OVPF)
San Cristobal | 25 April-1 May 2018 | New Activity / Unrest Cite this Report
San Cristobal Sierra de los Marrabios	INETER reported that at 1320 on 22 April a small explosion at San Cristóbal generated a gas-and-ash plume that rose 800 m and drifted SW, causing ashfall in the La Bolsa region and Hacienda Las Rojas. Source: Instituto Nicaragüense de Estudios Territoriales (INETER)
Semeru | 25 April-1 May 2018 | New Activity / Unrest Cite this Report
Semeru Eastern Java	Based on analysis of satellite images, the Darwin VAAC reported that on April a short-lived, discreet eruption at Semeru generated an ash plume that rose to an altitude of 3.4 km (11,000 ft) a.s.l. and drifted NW. Source: Darwin Volcanic Ash Advisory Centre (VAAC)

Agung | 25 April-1 May 2018 | Continuing ActivityCite this Report
Agung Bali	PVMBG reported that at 2245 on 30 April an event at Agung generated an ash plume that rose 1.5 km above the crater rim and drifted SW. Seismicity was dominated by low-frequency earthquakes related to gas-and-steam emissions. The Alert Level remained at 3 (on a scale of 1-4) and the exclusion zone continued at a 4-km radius. Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
Aira | 25 April-1 May 2018 | Continuing ActivityCite this Report
Aira Kyushu (Japan)	JMA reported that there were nine events and 30 explosions at Minamidake crater (at Aira Caldera’s Sakurajima volcano) during 20 April-1 May. Tephra was ejected as far as 1.3 km from the crater, and ash plumes rose as high as 3.3 km above the crater rim. Crater incandescence was visible at night on 20, 23, 26, and 30 April. The Alert Level remained at 3 (on a 5-level scale). Source: Japan Meteorological Agency (JMA)
Dukono | 25 April-1 May 2018 | Continuing ActivityCite this Report
Dukono Halmahera	Based on analyses of satellite imagery, wind model data, and notices from PVMBG, the Darwin VAAC reported that during 25 April-1 May ash plumes from Dukono rose to altitudes of 1.5-2.1 km (5,000-7,000 ft) a.s.l. and drifted NE, E, and SE. Sources: Darwin Volcanic Ash Advisory Centre (VAAC), Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
Ebeko | 25 April-1 May 2018 | Continuing ActivityCite this Report
Ebeko Paramushir Island (Russia)	Volcanologists in Severo-Kurilsk (Paramushir Island), about 7 km E of Ebeko, observed explosions during 21 and 25 April that sent ash plumes as high as 2.5 km (8,200 ft) a.s.l. The Aviation Color Code remained at Orange (the second highest level on a four-color scale). Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Kikai | 25 April-1 May 2018 | Continuing ActivityCite this Report
Kikai Ryukyu Islands (Japan)	JMA reported that the number of volcanic earthquakes at Satsuma Iwo-jima, a subaerial part of Kikai’s NW caldera rim, was low during 20-26 April. White plumes rose as high as 700 m above the Iwo-dake lava dome; incandescence from the crater had not been visible since 12 April. During field surveys on 25 and 26 April observers noted a slight expansion of a thermally anomalous area compared to 24-25 March observations, and a decrease in sulfur dioxide flux from 600 tons/day on 24 March to 300 tons/day. The Alert Level was reduced to 1 (on a 5-level scale) on 27 April. Source: Japan Meteorological Agency (JMA)
Pacaya | 25 April-1 May 2018 | Continuing ActivityCite this Report
Pacaya South-Central Guatemala	INSIVUMEH and CONRED reported that during 27-28 April seismicity at Pacaya had increased, and moderate-to-strong explosions ejected material as high as 150 m above the crater rim. Lava originating from the 2010 fissure traveled about 500 m NW, towards Cerro Chino. The report noted that ejected material has filled the crater. Sources: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH), Coordinadora Nacional para la Reducción de Desastres (CONRED)
Popocatepetl | 25 April-1 May 2018 | Continuing ActivityCite this Report
Popocatepetl Mexico	CENAPRED reported that each day during 25 April-1 May there were 63-114 steam and gas emissions from Popocatépetl, often containing ash. Incandescence from the crater was visible at night. As many as five explosions per day were recorded during 25-29 April, with resulting eruption plumes rising around 1 km above the crater rim. The Alert Level remained at Yellow, Phase Two. Source: Centro Nacional de Prevencion de Desastres (CENAPRED)
Reventador | 25 April-1 May 2018 | Continuing ActivityCite this Report
Reventador Ecuador	During 24 April-1 May IG reported a high level of seismic activity including explosions, long-period earthquakes, harmonic tremor, and signals indicating emissions at Reventador. Steam, gas, and ash plumes sometimes rose higher than 1 km above the crater rim and drifted NE, NW, and W. On 27 April incandescent blocks rolled as far as 800 m down the flanks, and a small pyroclastic flow traveled down the E flank. Source: Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN)
Sabancaya | 25 April-1 May 2018 | Continuing ActivityCite this Report
Sabancaya Peru	Observatorio Vulcanológico del Sur del IGP (OVS-IGP) and Observatorio Vulcanológico del INGEMMET (OVI) reported that explosive activity at Sabancaya was similar to the previous week; explosions averaged 22 per day during 23-29 April. Seismicity was dominated by long-period events and signals indicating emissions. Gas-and-ash plumes rose as high as 2 km above the crater rim and drifted 30 km NE and SE. The report noted that the public should not to approach the crater within a 12-km radius. Sources: Instituto Geológico Minero y Metalúrgico (INGEMMET), Instituto Geofísico del Perú (IGP)
Sheveluch | 25 April-1 May 2018 | Continuing ActivityCite this Report
Sheveluch Central Kamchatka (Russia)	KVERT reported that a weak thermal anomaly over Sheveluch was identified in satellite images during 21 and 23-25 April. The Aviation Color Code remained at Orange. Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Stromboli | 25 April-1 May 2018 | Continuing ActivityCite this Report
Stromboli Aeolian Islands (Italy)	INGV reported that on 24 April an intense explosive sequence occurred at vents on Stromboli’s south-central crater terrace area. The first explosion, recorded at 1105, ejected an abundant amount of ash, incandescent material, and large blocks to a height of 250 m that fell onto the summit area and along the Sciara del Fuoco. An explosive event at 1106 was characterized by modest lava fountaining. The last event, recorded at 1110, ejected pyroclastic material, though it was less intense than the first. An ash plume from the sequence quickly dispersed SE. Source: Sezione di Catania - Osservatorio Etneo (INGV)
Suwanosejima | 25 April-1 May 2018 | Continuing ActivityCite this Report
Suwanosejima Ryukyu Islands (Japan)	Based on JMA notices and satellite data, the Tokyo VAAC reported an explosion at Suwanosejima on 24 April, and that events during 27-29 April produced plumes that rose 1.2-2.1 km (4,000-7,000 ft) a.s.l. and drifted in multiple directions. Source: Tokyo Volcanic Ash Advisory Center (VAAC)
Turrialba | 25 April-1 May 2018 | Continuing ActivityCite this Report
Turrialba Costa Rica	OVSICORI-UNA reported that an event at Turrialba at 0700 on 26 April generated a small ash plume that rose 300 m above the crater rim and drifted W. Source: Observatorio Vulcanologico y Sismologico de Costa Rica-Universidad Nacional (OVSICORI-UNA)
Yasur | 25 April-1 May 2018 | Continuing ActivityCite this Report
Yasur Vanuatu	On 25 April the Vanuatu Meteorology and Geo-hazards Department (VMGD) reported that ongoing explosive activity at Yasur was confined to the crater. The Alert Level remained at 2 (on a scale of 0-4). VGO reminded residents and tourists that hazardous areas were near and around the volcanic crater, within a 395-m-radius permanent exclusion zone, and that volcanic ash and gas could reach areas impacted by trade winds. Source: Vanuatu Meteorology and Geohazards Department (VMGD)

Weekly Reports Archive

Since the Weekly Volcanic Activity Report began in November 2000, there have been 19,996 individual reports over 1,215 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.

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)