Aktiivsed vulkaanid

AVO reported that a 23 March satellite image confirmed that lava continued to slowly erupt at the summit of Great Sitkin, producing a thick lava flow. The flow advanced to the E and likely continued to be fed through 28 March. The Volcano Alert Level remained at Watch (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).

Source: US Geological Survey Alaska Volcano Observatory (AVO)

JMA reported that the eruption at Suwanosejima's Ontake Crater continued during 20-27 March. Eruptive activity including three explosions sent ash plumes as high as 2 km above the rim and ejecting large blocks as far as 300 m from the vent. Crater incandescence was visible nightly. Occasional ashfall was reported in Toshima village (3.5 km SSW). The Alert Level remained at 2 (on a 5-level scale) and residents were warned to stay 1 km away from the crater.

Source: Japan Meteorological Agency (JMA)

KVERT reported that the ongoing eruption at Sheveluch was generally characterized by explosions, hot avalanches, lava-dome extrusion, and strong fumarolic activity. A daily thermal anomaly was identified in satellite images during 16-23 March. 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)

KVERT reported that moderate activity at Ebeko was ongoing during 16-23 March. According to volcanologists in Severo-Kurilsk (Paramushir Island, about 7 km E) explosions during 18 and 21-22 March generated ash plumes that rose as high as 2.8 km (9,200 ft) a.s.l. and drifted NE and E. Ash plumes were identified in satellite images drifting 76 km E during 22-23 March. 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)

JMA reported ongoing eruptive activity at Minamidake Crater (at Aira Caldera?s Sakurajima volcano) during 20-27 March, with crater incandescence visible nightly. Two explosions recorded on 21 and 22 March produced ash plumes that rose 1.2 km above the crater rim and ejected large blocks 1-1.3 km from the vent. Two eruptive events during 24-27 March produced volcanic plumes that rose 1.1 km. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from both craters.

Source: Japan Meteorological Agency (JMA)

IG reported that eruptive activity at Cotopaxi was ongoing during 22-28 March. Gas-and-steam emissions were visible during 21-24 March rising as high as 1 km above the crater rim and drifting E; weather clouds prevented views of the volcano on 23 March. Ash emissions rose 500-800 m above the crater rim and drifted SW and SE during 25-26 March. Ash plumes rose 1.1 km above the crater rim and rifted SE, NE, and NW on 27 March. Ash plumes rose as high as 2 km above the crater rim on 28 March and drifted NW, causing minor ashfall in the Machachi parish on the N flank, in Parque Nacional Cotopaxi. Servicio Nacional de Gestión de Riesgos y Emergencias (SNGRE) maintained the Alert Level at Yellow (the second lowest level on a four-color scale).

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG) ,Servicio Nacional de Gestión de Riesgos y Emergencias (SNGRE),Washington Volcanic Ash Advisory Center (VAAC)

BPPTKG reported that the eruption at Merapi (on Java) continued during 17-23 March and seismicity remained at high levels. The SW lava dome produced 160 lava avalanches that traveled as far as 1.8 km down the SW flank (upstream in the Bebeng and Boyong drainages). Two pyroclastic flows traveled 1.3 km down the SW flank, upstream of the Bebeng/Krasak drainage. Morphological changes to the SW lava dome were evident in webcam images due to continuing collapses of material, though the volume remained unchanged at 1,686,200 cubic meters. 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)

Webcam images of Karangetang posted in PVMBG daily reports during 23-28 March showed incandescent material at the summit Main Crater (S crater) and on the flanks. The Alert Level remained at 3 (on a scale of 1-4) and the public were advised to stay 2.5 km away from Main Crater with an extension to 3.5 km on the S and SE flanks.

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

PVMBG reported that the eruption at Semeru continued during 22-28 March, with daily emissions of dense ash plumes. At 0605 and 0810 on 23 March gray and white-to-gray ash plumes rose 800 m above the summit and drifted NW and SW. At 0548 on 24 March a white-to-gray ash plume rose 1 km and drifted S. On 25 March at 0600 a white-to-gray ash plume rose 500 m and drifted S and SW, at 0705 a gray ash plume rose 700 m and drifted SE and S, and at 0738 a gray-to-brown ash plume rose 1.2 km and drifted SE. At 0619 and 0659 on 26 March dense white-to-gray ash plumes rose 1 km and drifted SE. At 0756 on 27 March a white-to-gray ash plume rose 800 m and drifted S. At 0130 on 28 March a dense gray ash plume drifted NE and at 0759 a somewhat dense white-to-gray plume rose 800 m and drifted N. The Alert Level remained at 3 (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, 100 m away from the banks of the Kobokan drainage as far as 17 km from the summit, and to avoid other drainages originating on Semeru, 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)

Unrest at Ahyi Seamount continued during 21-28 March. A plume of discolored water was observed in high-resolution satellite images acquired on 21 and 22 March. No observations indicated that activity has breached the ocean surface. One possible underwater explosion was detected by pressure sensors on Wake Island, 2,270 km E, during 26-27 March. 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

PVMBG reported that the eruption at Lewotolok was ongoing during 22-28 March. Daily ash plumes, sometimes dense, were visible rising as high as 800 m above the summit and drifting mainly W and NW. VONAs issued on most days described dense gray or gray-to-white ash plumes at 0517, 1623, and 2016 on 22 March, at 1744 on 24 March, at 0103 on 26 March, at 0845 and 1604 on 27 March, and at 0538 on 28 March. A webcam image at 2220 on 22 March showed incandescent material around the summit area and being ejected above the summit. Another webcam images at 0103 on 26 March captured a Strombolian explosion at 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 summit crater.

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

PVMBG reported that the eruption at Anak Krakatau continued during 22-29 March and multiple ash plumes were visible rising from the vent during 28-29 March. Ash plumes recorded at 0412, 0743, 1221, 1513, and 1935 on 28 March were dense and dark gray and rose as high has 2.5 km above the summit. The ash plumes drifted NE and W. Webcam images captured incandescent material being ejected above the vent at 0415 and around the summit area at 2003. At 0041 on 29 March a dense dark ash plume rose 600 m and drifted W. A webcam image from 0047 showed incandescent material at the vent. The Alert Level remained at 3 (on a scale of 1-4), and the public was warned to stay at least 5 km away from the crater.

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

AVO reported that low-level unrest continued at Semisopochnoi during 22-28 March. Steam emissions from the N crater of Mount Young were visible during 22 and 26-27 March. No explosive activity was detected in seismic or infrasound data. The Volcano Alert Level remained at Watch (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).

Source: US Geological Survey Alaska Volcano Observatory (AVO)

INSIVUMEH reported that 4-10 explosions per hour recorded at Fuego during 22-28 March generated ash plumes that rose as high as 1.1 km above the crater rim and drifted at least 25 km in multiple directions. Ashfall was reported almost daily in areas downwind including Morelia (9 km SW), Panimaché I and II (8 km SW), Santa Sofía (12 km SW), Finca Palo Verde, La Rochela, Sangre de Cristo (8 km WSW), El Porvenir (8 km ENE), Finca Asunción, Aldeas, and San Pedro Yepocapa (8 km NW). Ashfall was not confirmed during 23-24 March Explosions ejected incandescent material up to 200 m above the crater. Daily block avalanches descended the flanks in various directions towards the Ceniza (SSW), Santa Teresa, Seca (W), Taniluya (SW), Trinidad (S), Las Lajas (SE), Honda (E), and El Jute (ESE) ravines, sometimes reaching vegetated areas. Shockwaves caused structures to shake in communities around the volcano.

Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)

INSIVUMEH reported that the Santa Maria-Santiaguito lava dome complex remained highly active during 22-28 March. On most days steady degassing from the dome produced gas plumes that drifted S and SW. Incandescence from the dome and along lava flow margins was visible most nights or early mornings. The lava flow that extended 4.3 km down the SW flank in the San Isidro and Zanjón Seco drainages was active. Activity from the lava dome included explosions and avalanches, and small pyroclastic flows during 22-23 March. Daily weak to moderate explosions generated ash plumes up to 1 km above the crater that drifted SW and W, and avalanches traveled down multiple flanks.

Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)

JMA reported that inflation on Asamayama?s W flank began to be detected on 15 March, and the number of shallow volcanic earthquakes increased on 21 March. On 22 March JMA raised the Alert Level to 2 (on a scale of 1-5) and warned the public that very small eruptions may impact areas within 500 m of the crater.

Source: Japan Meteorological Agency (JMA)

KVERT reported that at 1825 on 29 March an ash plume from Bezymianny rose as high as 6 km (19,700 ft) a.s.l. and drifted NE. The Aviation Color Code was raised to Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

JMA reported that a submarine eruption occurred at Funka Asane, a submarine vent 4-5 km NW of Kita-Ioto, at around 1800 on 27 March based on satellite images.

Source: Japan Meteorological Agency (JMA)

RVO reported a short eruption at Ulawun, during 0408-0425 on 28 March, based on seismic data. A local volcano observer reported minor ashfall in areas to the NW including Ubili village, and the Ulamona Mission, Saltamana, and Ibana Village Oil Palm areas. According to the Darwin VAAC at 0600 an ash plume was visible in a satellite image drifting W at 3.4 km (11,000 ft) a.s.l.; the plume had dissipated by 1000.

Sources: Darwin Volcanic Ash Advisory Centre (VAAC),Rabaul Volcano Observatory (RVO)

The amplitude of volcanic tremor signals at Asosan increased in December 2022, and then further intensified on 30 January, prompting JMA to raise the Alert Level to 2 (on a scale of 1-5) and warn the public to stay at least 1 km away from the crater. The amplitude fluctuated at high levels for a few weeks, and then decreased on 19 February and again on 14 March. Daily sulfur dioxide emissions had exceeded 1,000 tons per day starting in December 2022; emissions declined to below that threshold by mid-January and remained at lower levels. At 1100 on 23 March the Alert Level was lowered to 1.

Source: Japan Meteorological Agency (JMA)

INGV reported that both explosive and effusive activity at Stromboli occurred during 20-26 March, though inclement weather conditions prevented views on most days. Activity was centered at three vents in Area N within the upper part of the Sciara del Fuoco, and from four vents in Area C-S (South-Central Crater) on the crater terrace. Explosions at two vents in the N1 crater and one vent in the N2 crater in Area N were low to medium intensity and ejected coarse material (bombs and lapilli) 80-150 m at a rate of 6-12 explosions per hour. Explosive activity at three active vents at the S2 sector in Area C-S ejected coarse material generally as high as 150 m above the vent at a rate of 5-7 explosions per hour; material was ejected as high as 300 m on 23 March. Sector C was characterized by occasional low-intensity explosive activity through the week and intense spattering on 22 March. No activity was recorded at sector S1. A strong explosion at 1549 on 25 March at Area C-S and was followed by two minor explosions; the sequence lasted about three minutes. A lava overflow event at one of the N1 vents began at 2242 on 23 March and was preceded by spattering activity in Area N. After about an hour lava flowed along the Sciara del Fuoco in the ravine that had formed in October 2022. The flow rate notably increased during 0200-0400 on 26 March and caused avalanches of material from collapses at the advancing flow front. By that afternoon the flow was cooling down and no longer being fed. It was unknown due to weather conditions if material reached the coastline.

Source: Sezione di Catania - Osservatorio Etneo (INGV)

The eruption at Villarrica was ongoing during 21-28 March. POVI reported that on 21 March Strombolian explosions ejected material 100 m above the crater rim. SERNAGEOMIN reported that at 0551 on 24 March a long-period earthquake was associated with low-intensity crater incandescence. According to POVI a cone with a vent that was about 13 m in diameter had formed on the crater floor and was visible during a recent overflight. Sometimes lava fountains rose over 100 m. At 2249 on 26 March Strombolian explosions ejected incandescent material more than 110 m above the crater rim. The Volcanic Alert level remained at Yellow (the second highest on a four-level scale) according to SERNAGEOMIN. SENAPRED maintained the Alert Level at Yellow (the middle level on a three-color scale) for the communities of Villarrica, Pucón (16 km N), Curarrehue, and Panguipulli, and SINAPRED maintained an exclusion zone of 1 km from the crater.

Sources: Proyecto Observación Villarrica Internet (POVI),Servicio Nacional de Geología y Minería (SERNAGEOMIN),Sistema y Servicio Nacional de Prevención y Repuesta Ante Desastres (SENAPRED)