Smithsonian / USGS Weekly Volcanic Activity Report

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 26 March-1 April 2025
Name	Country	Volcanic Region	Eruption Start Date	Report Status
Kirishimayama	Japan	Ryukyu Volcanic Arc	—	New
Lewotobi	Indonesia	Sunda Volcanic Arc	2023 Dec 23	New
Lewotolok	Indonesia	Sunda Volcanic Arc	2025 Jan 16	New
Poas	Costa Rica	Central America Volcanic Arc	2025 Jan 5	New
Reykjanes	Iceland	Iceland Neovolcanic Rift Volcanic Province	—	New
Ulawun	Papua New Guinea	Bismarck Volcanic Arc	—	New
Ahyi	United States	Mariana Volcanic Arc	2024 Aug 5	Continuing
Aira	Japan	Ryukyu Volcanic Arc	2017 Mar 25	Continuing
Ambae	Vanuatu	Vanuatu Volcanic Arc	—	Continuing
Awu	Indonesia	Sangihe Volcanic Arc	—	Continuing
Bezymianny	Russia	Eastern Kamchatka Volcanic Arc	2024 Dec 24	Continuing
Dukono	Indonesia	Halmahera Volcanic Arc	1933 Aug 13	Continuing
East Epi	Vanuatu	Vanuatu Volcanic Arc	—	Continuing
Gaua	Vanuatu	Vanuatu Volcanic Arc	—	Continuing
Great Sitkin	United States	Aleutian Ridge Volcanic Arc	2021 May 25	Continuing
Ibu	Indonesia	Halmahera Volcanic Arc	2008 Apr 5	Continuing
Kanlaon	Philippines	Negros-Sulu Volcanic Arc	2024 Oct 19	Continuing
Karymsky	Russia	Eastern Kamchatka Volcanic Arc	—	Continuing
Katmai	United States	Alaska Peninsula Volcanic Arc	—	Continuing
Kilauea	United States	Hawaiian-Emperor Hotspot Volcano Group	2024 Dec 23	Continuing
Lopevi	Vanuatu	Vanuatu Volcanic Arc	—	Continuing
Merapi	Indonesia	Sunda Volcanic Arc	2020 Dec 31	Continuing
Nevado del Ruiz	Colombia	Northern Andean Volcanic Arc	2014 Nov 18	Continuing
Semeru	Indonesia	Sunda Volcanic Arc	2017 Jun 6	Continuing
Sheveluch	Russia	Eastern Kamchatka Volcanic Arc	1999 Aug 15	Continuing
Suwanosejima	Japan	Ryukyu Volcanic Arc	2004 Oct 23	Continuing
Yasur	Vanuatu	Vanuatu Volcanic Arc	1270 ± 110 years	Continuing

All times are local unless otherwise stated.

Kirishimayama (Japan) | 26 March-1 April 2025 | New Activity / Unrest Cite this Report

Kirishimayama
Ryukyu Volcanic Arc

The Japan Meteorological Agency (JMA) reported increasing unrest at Shinmoedake (Shinmoe peak, a stratovolcano of the Kirishimayama volcano group). The number of earthquakes with epicenters beneath Shinmoedake began increasing on 28 March. At around 0250 on 30 March a tiltmeter recorded 0.1 microradians of inflation. A volcanic tremor signal was detected at 0256 and lasted 10 minutes. At 0353 the Alert Level was raised to 3 (on a 5-level scale) and the public was warned to exercise caution within 4 km from Shinmoedake Crater. The number of earthquakes subsequently decreased after the inflation was detected. A field team that was deployed to the volcano observed nothing indicating increased activity. On 2 April the warning zone was reduced to 3 km.

Source: Japan Meteorological Agency (JMA)

Lewotobi (Indonesia) | 26 March-1 April 2025 | New Activity / Unrest Cite this Report

Lewotobi
Sunda Volcanic Arc

The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that activity at Lewotobi Laki-laki significantly decreased after the more intense eruptive phase during 20-21 March, though ash plumes continued to be periodically observed. Minor incandescent at the summit was occasionally visible during 22-27 March, though absent during 28-30 March. Seismicity decreased overall; the number of earthquakes indicating emissions notably deceased, both low-frequency and volcanic earthquakes decreased, harmonic tremor fluctuated though was stable, and shallow volcanic earthquakes were not detected. The report warned that deposits of material especially on the WNW and NNE flanks increased the potential for lahars. During 25-26 March white plumes rose 100-500 m above the summit and drifted N and NE. On 26 March the exclusion zone was decreased to a radius of 6 km from the center of Laki-laki and 7 km in a semicircle clockwise from the SW to the NE. On 27 March white-and-gray plumes rose 100-300 m above the summit and drifted N and NE. During 28-30 March and 1 April white plumes rose 100-500 m above the summit and drifted in multiple directions. At 1200 on 30 March the Alert Level was lowered to 3 (on a scale of 1-4) and the public was warned to stay 6 km away from the center of Laki-laki. A white and gray plume rose 500 m above the summit on 31 March and drifted N and NE.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)

Lewotolok (Indonesia) | 26 March-1 April 2025 | New Activity / Unrest Cite this Report

Lewotolok
Sunda Volcanic Arc

The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that an eruption at Lewotolok was ongoing during 26 March-1 April. White steam-and-gas plumes rose 100 m above the summit and drifted E on 26 March. Weather conditions obscured views during 27-30 March, though a nighttime webcam image on 29 March showed incandescent material being ejected above the summit. On 31 March white-and-gray ash plumes rose 100 m and drifted E and SE; a nighttime webcam image again showed incandescent material being ejected above the summit. The Alert Level remained at 2 (on a scale of 1-4) and the public was warned to stay 2 km away from the vent and 2.5 km away on the S, SE, and W flanks.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)

Poas (Costa Rica) | 26 March-1 April 2025 | New Activity / Unrest Cite this Report

Poas
Central America Volcanic Arc

The Observatorio Vulcanológico y Sismológico de Costa Rica-Universidad Nacional (OVSICORI-UNA) reported increasing activity at Poás in late March with continuing activity at least through 1 April. Significant inflation, phreatomagmatic activity, and volcanic emissions were ongoing. During 23-26 March, small-to-moderate phreatomagmatic explosions at the Boca A and Boca C vents were almost continuous, and they intensified on 24 March. The explosions generated gas-and-steam plumes that rose as high as 150 m and ejected jets of sediments and tephra; material up to 10 cm in diameter was occasionally deposited on the W crater rim. Volcanic gas emissions were very high and indicated that the water content was decreasing while emissions of more toxic gases was increasing. Sulfur dioxide emissions detected in satellite data were as high as 600 tons per day (t/d) on 25 March. Sistema Nacional de Áreas de Conservación (SINAC) closed the Parque Nacional volcán Poás on 25 March. During 25-26 March gas emissions were nearly constant and volcanic plumes drifted E.

On 26 March activity again intensified; during clear conditions ash and bombs were observed being ejected 200 m from the vents and the gas-and-steam plumes contained an increase in ash content. During 27-28 March frequent-to-continuous explosions at Boca C produced gas-and-ash plumes that rose 300-400 m and drifted SW. An explosion at 1558 on 28 March generated a gas-and-ash plume that rose 500 m and drifted W. Activity decreased during the morning of 29 March; small but frequent eruptive events ejected material as high as 50 m and volcanic plumes containing low amounts of ash drifted W. Activity increased in the evening, and during 2030-2315 incandescent bombs were ejected from the vents. A volcanic plume rose 500 m and drifted SW at 2210, and an explosion at 2051 generated a volcanic plume that rose 1 km and drifted W. Ash deposits more than 5 mm deep were observed at the visitor overlook. Significant sulfur dioxide emissions were detected in satellite data. During 30 March-1 April eruptive activity was almost continuous, sulfur dioxide emissions remained high, and ash plumes mainly drifted SW. At 0052 on 31 March a high-energy eruptive event ejected incandescent blocks and material more than 600 m high and generated a gas-and-ash plume that drifted SW and W. Volcanic plumes rose 200 m and drifted NW almost an hour later. Comisión Nacional de Emergencias (CNE) announced an Alert Level Orange for the national park and district of Toro Amarillo in the Canton of Sarchí (including the Desagüe and Agrio river basins) due to increased activity in the crater, ashfall and sulfur odors impacting areas downwind, and a higher potential of lahars in drainages. On 1 April incandescent blocks continued to be ejected from the vents, sometimes as high as 400 m, and ash plumes drifted SW. The Alert Level remained at 3 (the second highest level on a four-level scale) and the Aviation Color Code remained at Orange (the second highest color on a four-color scale).

Sources: Observatorio Vulcanologico y Sismologico de Costa Rica-Universidad Nacional (OVSICORI-UNA), Comisión Nacional de Prevención de Riesgos y Atención de Emergencias (CNE), Sistema Nacional de Áreas de Conservación (SINAC)

Reykjanes (Iceland) | 26 March-1 April 2025 | New Activity / Unrest Cite this Report

Reykjanes
Iceland Neovolcanic Rift Volcanic Province

The Icelandic Meteorological Office (IMO) reported that an earthquake swarm at the Sundhnúkur crater row began at 0630 on 1 April, located between Stóra-Skógfell and Sýlingarfell within the Reykjanes volcanic system. Monitoring data showed related deformation, and pressure changes were detected in boreholes. IMO raised the Aviation Color Code to Orange (the second highest level on a four-color scale) at 0657 noting that magma was moving, and an eruption may begin within an hour or so. GPS signals indicated that magma was moving both NE and S towards Grindavík, and the intrusion was about 11 km long; emergency responders in Grindavík reported felt earthquakes and observed signs of deformation. According to a news report residents from about 40 occupied homes in Grindavík were evacuated; eight people decided to not evacuate. A M 4 earthquake was felt in Reykjavík.

A NE-SW-trending fissure opened at around 0945, just N of the protective barrier built around Grindavík, and by 1000 had grown to 500 m long. Lava fountains developed along the fissure and gas plumes rose about 2 km above the fissure. By 1024 the fissure had extended S and was erupting lava a few hundred meters inside the barrier, between the barrier and Grindavík; lava flowed slowly S. The Aviation Color Code was raised to Red at 1024 and then back to Orange at 1054; no ash was detected in the emissions. The fissure continued to extend S and by 1235 it was 1.2 km long and comprised of five segments. The nearest house was 500 m S. Seismicity continued to be detected along the length of the intrusion and was most intense at the N end, which extended more than 3 km beyond the extent of previous eruptive fissures. Lava traveled mainly NW at the N end of the fissure, mostly W and to a lesser extent to the E at the central portion of the fissure, and S from the S end of the fissure in the area between the barrier and the town. The Blue Lagoon spa area closed for the day according to a news report. Eruptive activity significantly decreased during 1340-1440, though seismicity was ongoing at both the N and S ends of the intrusion. Activity continued to decrease and by 1500 no activity was visible; drone and webcam recordings indicated only minor activity. Seismicity at the S end of the intrusion, near Grindavík, had decreased. Seismicity at the N end continued at a similar intensity and shifted even further N; earthquakes were located almost 9 km more N than the northernmost eruption fissure during the August 2024 eruption. The largest earthquakes was around a M 3 and was felt in Vogar, 7 km NW of the activity.

Sources: Icelandic Meteorological Office (IMO), Icelandic National Broadcasting Service (RUV)

Ulawun (Papua New Guinea) | 26 March-1 April 2025 | New Activity / Unrest Cite this Report

Ulawun
Bismarck Volcanic Arc

The Rabaul Volcano Observatory (RVO) reported that at 0800 on 27 March a dense, dark-gray ash plume rose 2-3 km above the Ulawun’s summit and drifted S. Two seismic stations, located 10 km NW and 6 km from the volcano, indicated that seismicity remained low, though small, low-frequency earthquakes within background noise were detected by both stations. Increase seismicity was detected at the station 10 km NW in Real-time Seismic-Amplitude Measurement (RSAM) data 1-2 hours before the eruptive event, peaked about 30 minutes after the event, and then decreased to near-background levels about three hours later. RVO noted that the ash event was likely over, though seismic data suggested that there was a low probability that small ash plumes could sometimes occur. Continuous low rumbling was heard on 28 March. During 28 March-1 April activity was low and diffuse plumes contained ash but over the week changed to only white steam plumes.

Operations were restored at the third, and primary, seismic station (UULA) 2.8 km from the summit, on the lower WSW flank, on 28 March. The station immediately began recording small low- and high-frequency volcanic earthquakes, with low-frequency earthquakes being the dominant signal. Both the number and magnitude of both types of earthquakes increased on 1 April.

Source: Rabaul Volcano Observatory (RVO)

Ahyi (United States) | 26 March-1 April 2025 | Continuing ActivityCite this Report

Ahyi
Mariana Volcanic Arc

Unrest at Ahyi Seamount may have continued during 21-28 March. A diffuse plume of discolored water in the vicinity of the seamount was last identified in a satellite image on 15 March, indicating possible submarine activity. The Aviation Color Code remained at Yellow (the second lowest level on a four-color scale) and the Volcano Alert Level remained at Advisory (the second lowest level on a four-level scale).

Source: US Geological Survey

Aira (Japan) | 26 March-1 April 2025 | Continuing ActivityCite this Report

Aira
Ryukyu Volcanic Arc

The Japan Meteorological Agency (JMA) reported ongoing eruptive activity at Minamidake Crater (Aira Caldera’s Sakurajima volcano) during 24-31 March. Nightly crater incandescence was visible in webcam images. An explosion at 1145 on 25 March generated an ash plume that rose 2.5 km above the crater rim and drifted E. The explosion ejected large blocks 500-700 m from the vent. Another explosion occurred at 2127 on 27 March. On 28 March sulfur dioxide emissions were very high at 3,100 tons per day. Eruptive events at 1213 and 1236 on 25 March and at 1447 on 30 March generated ash plumes that rose 1-1.3 km above the crater rim and drifted E or SE. The Alert Level remained at 3 (on a 5-level scale), and the public was warned to stay 2 km away from both the Minimadake and Showa craters.

Source: Japan Meteorological Agency (JMA)

Ambae (Vanuatu) | 26 March-1 April 2025 | Continuing ActivityCite this Report

Ambae
Vanuatu Volcanic Arc

On 27 March the Vanuatu Meteorology and Geohazards Department (VMGD) reported that steam and/or gas emissions from the active vents at Ambae were ongoing during March based on satellite images and webcam images. Sulfur dioxide emissions were detected in satellite data. Seismic data also confirmed ongoing unrest. The Alert Level remained at 2 (on a scale of 0-5), and the public was warned to stay outside of the Danger Zone, defined as a 2-km radius around the active vents in Lake Voui, and away from drainages during heavy rains.

Source: Vanuatu Meteorology and Geohazards Department (VMGD)

Awu (Indonesia) | 26 March-1 April 2025 | Continuing ActivityCite this Report

Awu
Sangihe Volcanic Arc

The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that seismicity at Awu had increased. During March fluctuating levels of emissions rose as high as 200 m above the lava dome on the main crater floor and did not indicate an increase in activity. Tiltmeter data continued to show an inflationary trend. On 28 March there was an increase in the number of low-frequency earthquakes, indicating fluid movement at depth, and was accompanied by a relatively high number of shallow volcanic earthquakes. The Alert Level remained at 2 (on a scale of 1-4) and the public was warned to stay 3 km away from the crater’s center.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)

Bezymianny (Russia) | 26 March-1 April 2025 | Continuing ActivityCite this Report

Bezymianny
Eastern Kamchatka Volcanic Arc

The Kamchatkan Volcanic Eruption Response Team (KVERT) reported that a thermal anomaly over Bezymianny was identified in satellite images during 20-27 March. According to the Institute of Volcanology and Seismology (IVS) of the Far Eastern Branch of the Russian Academy of Sciences (FEB RAS), incandescent debris avalanches descended the SE and/or E flanks and daily summit incandescence was visible during dark hours. An ash plume generated from a debris avalanche rose 100 m above the summit and drifted NE on 21 March. Weather conditions occasionally obscured webcam and satellite views. The Aviation Color Code remained at Orange (the second highest level on a four-color scale). Dates are reported in UTC; specific events are in local time where noted.

Sources: Kamchatkan Volcanic Eruption Response Team (KVERT), Institute of Volcanology and Seismology (IVS) of the Far Eastern Branch of the Russian Academy of Sciences (FEB RAS)

Dukono (Indonesia) | 26 March-1 April 2025 | Continuing ActivityCite this Report

Dukono
Halmahera Volcanic Arc

The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that the eruption at Dukono was ongoing during 26 March-1 April. Daily dense white-and-gray or gray ash plumes rose as high as 2.5 km above the crater rim and drifted in multiple directions. Rumbling and banging sounds were sometimes accompanied by strong booms during 26-28 March. The Alert Level remained at Level 2 (on a scale of 1-4) and the public was warned to stay 4 km away from the Malupang Warirang Crater.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)

East Epi (Vanuatu) | 26 March-1 April 2025 | Continuing ActivityCite this Report

East Epi
Vanuatu Volcanic Arc

On 27 March the Vanuatu Meteorology and Geohazards Department (VMGD) reported that minor unrest continued at East Epi during March. No activity was observed above the ocean surface by communities of Epi and neighboring islands, though signs of continuing volcanic unrest was detected in seismic data. The Alert Level remained at 1 (on a scale of 0-5) and the public was warned to stay outside of the Danger Zone, defined as a 2-km radius around the active submarine vent.

Source: Vanuatu Meteorology and Geohazards Department (VMGD)

Gaua (Vanuatu) | 26 March-1 April 2025 | Continuing ActivityCite this Report

Gaua
Vanuatu Volcanic Arc

On 27 March the Vanuatu Meteorology and Geohazards (VMGD) reported that volcanic emissions consisting of steam and/or gas continued to be emitted at Gaua based on satellite images. Sulfur dioxide gas was detected in the emissions on 1 March. The Alert Level remained at 2 (on a scale of 0-5) and the public was warned to stay away from the main cone.

Source: Vanuatu Meteorology and Geohazards Department (VMGD)

Great Sitkin (United States) | 26 March-1 April 2025 | Continuing ActivityCite this Report

Great Sitkin
Aleutian Ridge Volcanic Arc

The Alaska Volcano Observatory (AVO) reported that slow lava effusion continued to feed a thick flow in Great Sitkin’s summit crater during 26 March-1 April. Small daily earthquakes were detected by the seismic network. Slightly elevated surface temperatures were observed in satellite data during most of the week. Typical minor steaming from the vent region was visible in webcam images during 25-26 March and 30-31 March. The Volcano Alert Level remained at Watch (the third level on a four-level scale) and the Aviation Color Code remained at Orange (the third color on a four-color scale).

Source: US Geological Survey Alaska Volcano Observatory (AVO)

Ibu (Indonesia) | 26 March-1 April 2025 | Continuing ActivityCite this Report

Ibu
Halmahera Volcanic Arc

The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that the eruption at Ibu continued during 26 March-1 April. Daily dense gray ash plumes rose 300-1,200 m above the summit and drifted in multiple directions. Incandescence at the summit was visible in several webcam images posted with the reports. The Alert Level remained at 3 (the second highest level on a four-level scale) and the public was advised to stay 4 km away from the active crater and 5 km away from the N crater wall opening.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)

Kanlaon (Philippines) | 26 March-1 April 2025 | Continuing ActivityCite this Report

Kanlaon
Negros-Sulu Volcanic Arc

The Philippine Institute of Volcanology and Seismology (PHIVOLCS) reported continuing eruptive activity at Kanlaon during 25 March-1 April. The seismic network recorded 6-23 daily volcanic earthquakes, including one period of volcanic tremor lasting one hour and 26 minutes on 29 March and one period of volcanic tremor lasting seven minutes on 31 March. Average daily sulfur dioxide emissions ranged from 1,665 to 3,302 tonnes per day. Moderate-to-voluminous, gas-and-steam emissions that occasionally contained ash generally rose 100-750 m crater rim and drifted W, WSW, and SW; weather conditions obscured views on 28 and 30 March. A period of ash emissions during 1524-1845 on 31 March produced voluminous plumes that rose up to 1.5 km above the crater rim and drifted W. According to a news article minor ashfall was reported in the barangays of Sag-ang in La Castellana (15 km SW) and Ara-al (7 km W) in La Carlota City, along with Binubuhan (17 km WNW), Ilijan (10 km NW), Ma-ao (17 km NW), and Mailum (11 km NW) in Bago City, Quintia. Ash emissions during 0557-0614, 0759-1001, 1028-1041, and 1140-1224 on 1 April rose 300-500 m above the crater rim and drifted SW. The Alert Level remained at 3 (on a scale of 0-5); the public was warned to stay 6 km away from the summit and pilots were warned not to fly close to the volcano.

Sources: Philippine Institute of Volcanology and Seismology (PHIVOLCS), Digicast Negros

Karymsky (Russia) | 26 March-1 April 2025 | Continuing ActivityCite this Report

Karymsky
Eastern Kamchatka Volcanic Arc

The Kamchatkan Volcanic Eruption Response Team (KVERT) reported moderate levels of activity at Karymsky during 20-27 March. Thermal anomalies over the volcano were identified in satellite images on 21 March; weather clouds obscured views on the other days. On 30 March, KVERT lowered the Aviation Color Code from Orange (the third level on a four-color scale) to Yellow (the second level on a four-color scale), noting that eruptive activity was last observed on 12 November 2024. Dates are based on UTC times; specific events are in local time where noted.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

Katmai (United States) | 26 March-1 April 2025 | Continuing ActivityCite this Report

Katmai
Alaska Peninsula Volcanic Arc

The Alaska Volcano Observatory (AVO) reported that on 31 March strong winds in the vicinity of Katmai and the Valley of Ten Thousand Smokes dispersed unconsolidated ash up to 1.2 km (4,000 ft) a.s.l. to the SE. The ash was originally deposited during the Novarupta-Katmai eruption in 1912. The Volcano Alert Level remained at Normal (the lowest level on a four-level scale) and the Aviation Color Code remained at Green (the lowest level on a four-color scale).

Source: US Geological Survey Alaska Volcano Observatory (AVO)

Kilauea (United States) | 26 March-1 April 2025 | Continuing ActivityCite this Report

Kilauea
Hawaiian-Emperor Hotspot Volcano Group

The Hawaiian Volcano Observatory (HVO) reported that the eruption within Kilauea’s Kaluapele summit caldera, from vents along the SW margin of Halema’uma’u Crater, continued at variable levels during 25 March-1 April. After a few days of no lava effusion from the N and S vents, activity resumed on 25 March. Eight cycles of rising lava in the N vent and small spatter fountaining were recorded during 0927-1155, with each cycle lasting 5-10 minutes and ending with lava draining back into the vent. At 1204 a more dynamic cycle began at the N vent with vigorous dome fountaining 10-20 m high and overflows of lava that extended onto the crater floor. Intermittent activity at the S vent also sent lava onto the crater floor. The cycles at the N vent continued through the day and by 0936 on 26 March nearly 100 cycles had been counted. Lava covered about 20 percent of the crater floor.

The cycles began to transition to lava fountaining at 1000 on 26 March, and by 1020 both vents were producing sustained fountains that rose more than 180 m. By 1045 fountains at the S vent were rising 180-210 m while N vent fountains were rising about half as high. Fountains at the S vent rose as high as 305 m during 1100-1200 and again at around 1330. Just after 1330 the S vent fountain began to incline, or bend over, with fountaining directed toward the SE. The inclined fountaining reappeared intermittently through the afternoon hours, with a maximum inclination approaching 45 degrees. By 1730 S vent fountains was vertical again with sustained heights of 150-215 m. Activity at the N vent ceased at around 1200 and fountaining at the S vent stopped at 1910. Lava flows covered 80-90 percent of the crater floor. Pele’s Hair and tephra was reported on surfaces in areas within Hawai’i Volcanoes National Park and surrounding communities. Sulfur dioxide gas emissions were estimated to be 50,000 tons per day during the periods of intense lava fountaining.

During 27-31 March spots of orange glow on the crater floor were visible at night, though diminished each day as the erupted lava cooled. Incandescent from the N vent was absent possibly due to being infilled with tephra and spatter from the S vent. A small opening in the S vent degassed and weakly glowed weakly during 27-28 March, was dark for a few nights, then was sporadically incandescent during 30-31 March.

Weak spattering began at the N vent at 1720 on 31 March. The spattering became continuous and by 1800 low lava fountains rose 5-10 m. The lava level in the vent gradually rose and overflowed at 2257, sending lava onto the crater floor. Incandescence from the S vent was visible overnight during 31 March-1 April and minor spattering was first observed by field crews at 0830 on 1 April. By 0944 lava covered only five percent of the crater floor. Fountaining at the S vent began and rapidly increased, rising to over 70 m by 1040 and exceeding 215 m by 1050. Low dome fountaining and overflows continue from the N vent. The Volcano Alert Level remained at Watch (the third level on a four-level scale) and the Aviation Color Code remained at Orange (the third color on a four-color scale).

Source: US Geological Survey Hawaiian Volcano Observatory (HVO)

Lopevi (Vanuatu) | 26 March-1 April 2025 | Continuing ActivityCite this Report

Lopevi
Vanuatu Volcanic Arc

On 27 March the Vanuatu Meteorology and Geohazards Department (VMGD) reported that during the previous month small fumarolic steam plumes were continuously emitted at Lopevi’s summit crater based on recent photos and webcam images. Low-level thermal anomalies were identified in satellite images on 19 and 24 March. Seismic data confirmed continuing unrest. The Alert Level remained at 2 (on a scale of 0-4).

Source: Vanuatu Meteorology and Geohazards Department (VMGD)

Merapi (Indonesia) | 26 March-1 April 2025 | Continuing ActivityCite this Report

Merapi
Sunda Volcanic Arc

The Balai Penyelidikan dan Pengembangan Teknologi Kebencanaan Geologi (BPPTKG) reported that the eruption at Merapi (on Java) continued during 21-27 March. Seismicity was at higher levels than the previous week. The SW lava dome produced 23 lava avalanches that traveled as far as 1.9 km SW down the Bebeng drainage, 20 that traveled as far as 2 km SW down the Krasak drainage, and 26 that traveled as far as 2 km W down the Sat/Putih drainage. Slight morphological changes to the SW lava dome resulted from minor collapses of material. The Alert Level remained at 3 (on a scale of 1-4), and the public was warned to stay 3-7 km away from the summit, based on location.

Source: Balai Penyelidikan dan Pengembangan Teknologi Kebencanaan Geologi (BPPTKG)

Nevado del Ruiz (Colombia) | 26 March-1 April 2025 | Continuing ActivityCite this Report

Nevado del Ruiz
Northern Andean Volcanic Arc

The Servicio Geológico Colombiano’s (SGC) Observatorio Vulcanológico y Sismológico de Manizales reported that eruptive activity at Nevado del Ruiz continued during 25-31 March. Seismic data indicated that events associated with fluid movement decreased in both number and intensity compared to the previous week, though long-duration signals slightly increased. Some of the seismic events were associated with pulsating ash emissions; webcam images confirmed these ash emissions, including some with higher-temperature ejecta. Gas plumes rose as high as 1 km above the summit; at 1744 on 25 March a gas-and-ash plume rose as high as 1.9 km above the summit as it drifted SW and W. Seismicity associated with rock fracturing decreased in both number and magnitude compared to the previous week. The earthquakes were mainly located below Arenas Crater, the NE and SW flanks within 4 km, and the W and NW flanks within 14 km, with depths of 1-10 km. Low-energy thermal anomalies on the crater floor were identified in satellite data. Sulfur dioxide emissions detected in satellite data continued to be significant. The Alert Level remained at Yellow (the second level on a four-level scale), and the public was warned to stay out of the restricted areas around Arenas Crater, not to spend long periods of time on the Murillo-Cerro Gualí Road, and to avoid drainages in the high-threat zones.

Source: Servicio Geológico Colombiano (SGC)

Semeru (Indonesia) | 26 March-1 April 2025 | Continuing ActivityCite this Report

Semeru
Sunda Volcanic Arc

The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that activity continued at Semeru during 26 March-1 April, with multiple eruptive events recorded daily by the seismic network. Daily dense white-and-gray or gray-to-black ash plumes rose 300-800 m above the summit and drifted N, NE, E, and S. Incandescence at the summit was visible in webcam images from 1 April. The Alert Level remained at 2 (the second lowest level on a scale of 1-4). The public was warned to stay at least 5 km away from the summit in all directions, 13 km from the summit to the SE, 500 m from the banks of the Kobokan drainage as far as 17 km from the summit, and to avoid other drainages including the Bang, Kembar, and Sat, due to lahar, avalanche, and pyroclastic flow hazards.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)

Sheveluch (Russia) | 26 March-1 April 2025 | Continuing ActivityCite this Report

Sheveluch
Eastern Kamchatka Volcanic Arc

The Kamchatkan Volcanic Eruption Response Team (KVERT) reported that lava extrusion may have continued at Sheveluch’s “300 years of RAS” dome on the SW flank of Old Sheveluch and at the Young Sheveluch dome during 20-27 March. Thermal anomalies over the domes were identified in satellite images during 21-22 and 25-26 March; weather clouds obscured views on the other days. The Aviation Color Code remained at Orange (the second highest level on a four-color scale). Dates are based on UTC times; specific events are in local time where noted.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

Suwanosejima (Japan) | 26 March-1 April 2025 | Continuing ActivityCite this Report

Suwanosejima
Ryukyu Volcanic Arc

The Japan Meteorological Agency (JMA) reported that eruptive activity at Suwanosejima's Ontake Crater continued during 24-31 March. Incandescence was observed nightly in webcam images. An eruptive event at 0927 on 29 March generated an ash plume that rose 1.5 km above the summit and drifted SE. Then at 1740 on 29 March an explosion generated an ash plume that rose 1 km into weather clouds. The Alert Level remained at 2 (the second level on a five-level scale) and the public was warned to stay at least 1.5 km away from the crater.

Source: Japan Meteorological Agency (JMA)

Yasur (Vanuatu) | 26 March-1 April 2025 | Continuing ActivityCite this Report

Yasur
Vanuatu Volcanic Arc

On 27 March the Vanuatu Meteorology and Geohazards Department (VMGD) reported that activity at Yasur continued at a level of “major unrest,” as defined by the Alert Level 2 status (on a scale of 0-5). Satellite and webcam images indicated that explosions continued, producing emissions of gas, steam, and/or ash. Sulfur dioxide gas emissions and low-level thermal anomalies were identified in satellite images. Seismic data confirmed continuing volcanic activity with explosions that were occasionally strong. The report warned that ejected material from explosions could fall in and around the crater. The public was reminded to not enter the restricted area within 600 m around the boundaries of the Permanent Exclusion Zone, defined by Danger Zone A on the hazard map.

Source: Vanuatu Meteorology and Geohazards Department (VMGD)

Weekly Reports Archive

Since the Weekly Volcanic Activity Report began in November 2000, there have been 21,181 individual reports over 1,266 weeks (average of 17 per week) on 339 different volcanoes.

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

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Puyehue-Cordon Caulle

Dieng Volcanic Complex

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Campi Flegrei del Mar di Sicilia

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News Feeds and Google Placemarks

Download Smithsonian / USGS Weekly Volcanic Activity Report Network RSS Feed

The RSS (Really Simple Syndication) feed is identical to the Weekly Volcanic Activity Report minus some features including the header information (latitude and longitude and summit elevation), the Geologic Summary, and a link to the volcano's page from the Global Volcanism Program. At the end of each report is a list of the sources used. Each volcano report includes a link from the volcano's name back to the more complete information in the Weekly Volcanic Activity Report on the Smithsonian website. This feature was first made available on 5 March 2008.

Download Smithsonian / USGS Weekly Volcanic Activity Report Network CAP Feed

The CAP (Common Alerting Protocol) feeds are XML files specifically formatted for disaster management. They are similar in content to the RSS feed, but contain no active links.

Download Smithsonian / USGS Weekly Volcanic Activity Report Network Link

A Google Earth network link for the Weekly Volcanic Activity Report can be loaded into the free Google Earth software, and in turn will load placemarks for volcanoes in the current weekly report. Placemark balloons include the volcano name, report date, report text, sources, and links back to the GVP volcano profile page and to the complete Weekly Report for that week. This feature was first made available on 1 April 2009.

Criteria & Disclaimers

Criteria

The Weekly Volcanic Activity Report does not necessarily include all volcanic activity that occurred on Earth during the week. More than a dozen volcanoes globally have displayed more-or-less continuous eruptive activity for decades or longer, and such routine activity is typically not reported here. Moreover, Earth's sea-floor volcanism is seldom reported even though in theory it represents the single most prolific source of erupted material. The Weekly Volcanic Activity Report summarizes volcanic activity that meets one or more of the following criteria:

- A volcano observatory raises or lowers the alert level at the volcano.
- A volcanic ash advisory has been released by a volcanic ash advisory center (VAAC) stating that an ash cloud has been produced from the volcano.
- A verifiable news report of new activity or a change in activity at the volcano has been issued.
- Observers have reported a significant change in volcanic activity. Such activity can include, but is not restricted to, pyroclastic flows, lahars, lava flows, dome collapse, or increased unrest.

Volcanoes are included in the "New Activity/Unrest" section of the Weekly Volcanic Activity Report if the activity occurs after at least 3 months of quiescence. Once a volcano is included in the "New Activity/Unrest" section, updates will remain in that section unless the activity continues for more than 1 month without escalating, after which time updates will be listed in the "Continuing Activity" section. Volcanoes are also included in the "New Activity/Unrest" section if the volcano is undergoing a period of relatively high unrest, or increasing unrest. This is commonly equal to Alert Level Orange on a scale of Green, Yellow, Orange, Red, where Red is the highest alert. Or alert level 3 on a scale of 1-4 or 1-5.

It is important to note that volcanic activity meeting one or more of these criteria may occur during the week, but may not be included in the Weekly Volcanic Activity Report because we did not receive a report.

Disclaimers

1. The Weekly Volcanic Activity Report is intended to provide timely information about global volcanism on a weekly basis. Consequently, the report is generated rapidly by summarizing volcanic reports from various sources, with little time for fact checking. The accuracy of the Weekly Volcanic Activity Report is dependent upon the quality of the volcanic activity reports we receive. Reports published in the Bulletin of the Global Volcanism Network are cover longer time periods and are more carefully reviewed, although all of the volcanoes discussed in the Weekly Volcanic Activity Report are not necessarily reported in the Bulletin. Because of our emphasis on rapid reporting on the web we have avoided diacritical marks. Reports are updated on the Weekly Volcanic Activity Report web page as they are received, therefore information may be included regarding events that occurred before the current report period.

2. Rapidly developing events lead to coverage that is often fragmentary. Volcanoes, their eruptions, and their plumes and associated atmospheric effects are complex phenomena that may require months to years of data analysis in order to create a comprehensive summary and interpretation of events.

3. Preliminary accounts sometimes contain exaggerations and "false alarms," and accordingly, this report may include some events ultimately found to be erroneous or misleading.

4. Many news agencies do not archive the articles they post on the Internet, and therefore the links to some sources may not be active. To obtain information about the cited articles that are no longer available on the Internet contact the source.

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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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URL: https://volcano.si.edu/reports_weekly.cfm