Volcanos

Roundup of Global Volcanic Activity – Ongoing activity for the week 22 March – 28 March 2023

Ahyi – Mariana Islands (USA) : 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.

Aira – Kyushu (Japan) : 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.

Asosan – Kyushu (Japan) : The amplitude of volcanic tremor signals at Asosan increased in December 2022, and then further intensified on 30 January. 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.

Cotopaxi – Ecuador : 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.

Ebeko – Paramushir Island (Russia) : 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.

Fuego – South-Central Guatemala : 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.

Great Sitkin – Andreanof Islands (USA) : 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.

Karangetang – Sangihe Islands : 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.

Krakatau – Sunda Strait : 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.

Lewotolok – Lembata Island : 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.

Merapi – Central Java : 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.

Santa Maria – Southwestern Guatemala : 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.

Semeru – Eastern Java : 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.

Semisopochnoi – Aleutian Islands (USA) : 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.

Sheveluch – Central Kamchatka (Russia) : 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.

Stromboli – Aeolian Islands (Italy) : 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.

Suwanosejima – Ryukyu Islands (Japan) : 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).

Villarrica – Central Chile : 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.

Volcanos

Roundup of Global Volcanic Activity – New activity for the week 22 March – 28 March 2023

Asamayama – Honshu (Japan) : 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 warned the public that very small eruptions may impact areas within 500 m of the crater.

Bezymianny – Central Kamchatka (Russia) : 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.

Kita-Ioto – Volcano Islands : 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.

Ulawun – New Britain (Papua New Guinea) : 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.

Volcanos

Roundup of Global Volcanic Activity – Ongoing activity for the week 15 March – 21 March 2023

Ahyi – Mariana Islands (USA) : Unrest at Ahyi Seamount continued during 15-21 March. A total of three short (~30 seconds) hydroacoustic detections from the direction of Ahyi were detected by pressure sensors on Wake Island, 2,270 km E, during 17-19 March. Weather clouds often prevented satellite views. Data was not available during 20-21 March due to an outage, though a plume of discoloured water was visible in satellite images.

Aira – Kyushu (Japan) : JMA reported ongoing eruptive activity at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) during 13-20 March, with crater Incandescence visible nightly. Sulfur dioxide emissions were high at 2,100 tons per day on 13 March. On 14 March an explosion produced an ash plume that rose 1 km above the crater rim. Three eruptive events were recorded during 17-20 February, producing volcanic plumes that rose as high as 1 km. No activity or crater incandescence was detected at Showa Crater.

Cotopaxi – Ecuador : IG reported that eruptive activity at Cotopaxi was ongoing during 15-21 March. Gas-and-steam emissions were visible on most days rising as high as 1 km above the crater rim and drifting in multiple directions. On 16 March several gas emissions containing minor amounts of ash rose as high as 1.5 km and drifted SE. During 19-20 March ash-and-gas plumes rose 1-1.5 km and drifted E and SE.

Dukono – Halmahera : PVMBG reported that white-and-gray plumes of variable densities rose from Dukono as high as 450 m above the summit and drifted N and W during 15-16, 18, and 20 March. No plumes were observed on 17 March, but white steam-and-gas plumes rose 150 m and drifted W on 19 March.

Ebeko – Paramushir Island (Russia) : KVERT reported that moderate activity at Ebeko was ongoing during 9-16 March. According to volcanologists in Severo-Kurilsk (Paramushir Island, about 7 km E) explosions during 10-12 March generated ash plumes that rose as high as 3.5 km (11,500 ft) a.s.l. and drifted NE and NW. A thermal anomaly was identified in satellite images on 10 and 13 March.

Fuego – South-Central Guatemala : INSIVUMEH reported that 4-10 explosions per hour were recorded at Fuego during 15-21 March, ejecting incandescent material up to 400 m above the crater and generating ash plumes that rose as high as 1.3 km above the crater rim. The ash plumes drifted as far as 20 km in multiple directions. Ashfall was reported on a few of the days in areas downwind including, Morelia (9 km SW), Panimaché I and II (8 km SW), Santa Sofía (12 km SW), El Porvenir (8 km ENE), Finca Palo Verde, La Rochela, Finca Asunción, Ceilán, San Andrés Osuna, Aldeas, and San Pedro Yepocapa (8 km NW). 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 immediately surrounding the volcano. A lahar notice issued at 1530 on 15 March described lahars in the Ceniza ravine that carried branches, tree trunks, and blocks 30 cm to 1.5 m in diameter. Lahars on 18 March descended the El Jute and Las Lahas drainages, carrying branches, tree trunks, and blocks 30 cm to 1.5 m in diameter.

Great Sitkin – Andreanof Islands (USA) : AVO reported that eruptive activity at Great Sitkin continued during 15-21 March, characterized by the eruption of lava that was confined to the summit crater. Radar data from 20 March confirmed slow growth of the lava flow.

Ibu – Halmahera : PVMBG reported that the eruption at Ibu continued during 15-18 March. White-and-gray plumes of variable densities rose as high as 800 m above the summit and drifted N, SE, SW, and W. The Darwin VAAC reported that on 20 March ash plumes rose to 2.1 km (7,000 ft) a.s.l., or about 800 m above the summit, and drifted SW based on satellite images.

Karangetang – Sangihe Islands : PVMBG reported that the summit Main Crater (S crater) on Karangetang continued to erupt during 15-21 March. Incandescent material at the summit and on the flanks was evident in webcam images captured at 0007 and 2345 on 16 March,1828 on 17 March, 1940 on 18 March, 2311 on 19 March, and 2351 on 20 March. The incandescence was most intense on 18 and 20 March, with webcam images possibly capturing Strombolian explosions. Based on satellite images, the Darwin VAAC reported that on 18 March an ash plume rose to 2.4 km (6,000 ft) a.s.l. and drifted SW and a thermal anomaly was visible.

Kilauea – Hawaiian Islands (USA): On 21 March HVO reported that Kilauea was no longer erupting. The lava lake in Halema’uma’u Crater was no longer being supplied as of 7 March based on lava lake levels and crater floor observations. Sulfur dioxide emissions had decreased to near pre-eruption background levels.

Krakatau – Sunda Strait : The Darwin VAAC reported that at 1446 on 18 March white-and-gray ash plumes at Anak Krakatau rose about 500 m above the summit and drifted SW. At 1846 on that same day a gray ash plume rose 300 m and drifted SW. An eruptive event was recorded at 2143, though it was not visible due to darkness.

Lewotolok – Lembata Island : PVMBG reported that the eruption at Lewotolok was ongoing during 15-21 March. White gas-and-steam plumes rose as high as 500 m above the summit and drifted in multiple directions during 15-19 March. White-and-gray ash plumes rose 400-600 m above the summit and drifted W and NW during 20-21 March.

Marapi – Central Sumatra : PVMBG reported that on 17 March a white-and-gray plume from Marapi (on Sumatra) rose as high as 400 m above the summit and drifted N and E. Emissions were not observed on other days during 15-19 March, though some of the days were cloudy. White gas plumes rose 50 m above the summit on 20 March.

Mauna Loa – Hawaiian Islands (USA) : HVO reported that Mauna Loa had been quiet since the eruption ended on 13 December 2022 and the number of earthquakes beneath the summit had returned to background levels. Inflation continued as magma replenished the summit reservoir.

Nevado del Ruiz – Colombia : Servicio Geológico Colombiano (SGC) reported that several ash emissions at Nevado del Ruiz were visible in webcam images and reported by residents during 18-20 March. The emissions were associated with seismic signals indicating fluid movement in the conduit. An ash emission at 0902 on 20 March rose 2.7 km above the summit and drifted SW. It was one of the tallest plumes recorded in recent days and was visible from the municipalities of Caldas, Tolima, and Risaralda.

Popocatepetl – Mexico : CENAPRED reported that there were 110-236 steam-and-gas emissions, sometimes containing minor amounts of ash, rising from Popocatépetl each day during 14-21 March; explosions also occurred almost daily. On 15 March a moderately-sized explosion recorded at 0009 was followed by minor explosions at 0058, 0220, 0641, 1215, 1509, and 2105, with another moderate explosion at 1848. On 16 March minor explosions were recorded at 0155 and 2215, and on 17 March they were recorded at 1441, 2105, and 2349. On 19 March multiple minor explosions were recorded, at 0003, 0220, 0926, and 2023, and moderate explosions occurred at 0501, 1300, and 1315. Minor explosions on 20 March were recorded at 0013, 0200, 0226, and 2112, and a moderate one occurred at 1404. A minor explosion occurred at 1712 on 21 March. According to the Washington VAAC daily ash plumes rose to 6.1-8.2 (20,000-27,000 ft) a.s.l., or around as high as 2.8 km above the summit, and drifted mainly N, NE, and S.

San Miguel – Eastern El Salvador : On 16 March MARN reported that gas emissions at San Miguel had decreased in the past few days and noted that gas-and-ash plumes were last observed on 9 March.

Santa Maria – Southwestern Guatemala : INSIVUMEH reported that the Santa Maria-Santiaguito lava dome complex remained highly active during 15-21 March. Emissions of gas and steam rose up to 800 m above the crater and drifted S, SW, and SE. Almost daily explosions produced ash plumes that rose as high as 800 m above the summit and often drifted SW. Effusion from Caliente dome fed lava flows that slowly descended the San Isidro and Zanjón Seco drainages on the W and SW flanks. Incandescence from the dome during the nights and early mornings. Block-and-ash flows originated from Caliente, and the middle and front of the lava flow. Lahars descended the Cabello de Ángel drainage (a tributary of Nimá I on the SE flank) on 19 March and consisted of a cement-like mixture of volcanic material, branches, and tree trunks.

Semeru – Eastern Java : PVMBG reported that the eruption at Semeru continued during 15-21 March. Dense ash plumes were visible almost daily. At 0737 and 0748 on 15 March white-and-gray ash plumes rose 600-800 m above the summit and drifted S and SE. At 0601 on 16 March a white-and-gray ash plume rose 600 m and drifted S, and at 0748 a gray-to-brown ash plume rose 500 m and drifted SW and W. At 0534 on 18 March a white-and-gray ash plume rose 500 m and drifted SW. Just over an hour later, at 0655, a white-and-gray ash plume rose 1 km and drifted S. At 0713 on 20 March white-and-gray ash plume rose 600 m and drifted SW and W, and at 0811 a gray-to-brown ash plume rose 1 km and drifted S.

Sheveluch – Central Kamchatka (Russia) : 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 9-16 March. Ash plumes drifted as far as 62 km E on 11 March.

Suwanosejima – Ryukyu Islands (Japan) : JMA reported that the eruption at Suwanosejima’s Ontake Crater continued during 13-20 March. A total of 20 explosions were recorded, sending ash plumes as high as 2.4 km above the crater rim and ejecting large blocks as far as 500 m from the vent. Crater incandescence was visible at night. Occasional ashfall was reported in Toshima village (3.5 km SSW).

Volcanos

Roundup of Global Volcanic Activity – New activity for the week 15 March – 21 March 2023

Merapi – Central Java : BPPTKG summarized the eruption at Merapi (on Java) during 10-16 March, including the collapses at the SW lava dome that began on 11 March and continued through the week. A total of 68 pyroclastic flows traveled as far as 4 km down the Bebeng and Krasak drainages on the SW flank. The largest pyroclastic flows were recorded during 11-12 March, which caused ashfall of varying intensity in areas to the W, NW, and N including in Dukun District, Sawangan, Magelang Regency; Magelang City; Selo District, Boyolali Regency; Ambarawa, Jambu, Sumowono, Pringapus, Banyubiru, Bawen Districts, Semarang Regency. Morphological changes to the SW lava domes were evident in webcam and drone images. The volume of the dome before 11 March was 2,759,100 cubic meters and by 13 March the dome volume had decreased to 1,686,200 cubic meters, with an estimate volume loss of 1,072,800 cubic meters. The volume of the summit dome remained unchanged and was estimated at 2,312,100 cubic meters. According to the Darwin VAAC ash plumes were visible in webcam images on 15 and 17 March rising as high as 1.2 km above the summit and drifting S and W, respectively. On both days weather conditions prevented satellite image views. During 16-20 March BPPTKG reported 14-38 daily counts of lava avalanches with material descending the SW flank as far as 1.8 km. Daily counts were not available for 17 March, though incandescent avalanches were visible in webcam footage; rainy weather sometimes prevented visual observations.

Nyamulagira – DR Congo : An 18 March satellite image of Nyamulagira showed a large thermal anomaly, possibly 600 m wide, in the summit crater, indicating that the eruption that had begun on 14 March was continuing.

Semisopochnoi – Aleutian Islands (USA) : AVO reported that low-level ash emissions from the N crater of Semisopochnoi’s Mount Young were observed in several web camera images during 18-19 March. Small explosions and volcanic tremor had also resumed. Ash emissions were not detected in satellite images, though on 18 March a robust steam-and-gas plume was visible drifting 150 km from the N crater. Low-level seismicity continued during 20-21 March and one small explosion was detected in seismic and infrasound data. Clouds obscured webcam and satellite views.

Takawangha – Andreanof Islands (USA) : AVO reported that earthquake activity near Takawangha had decreased in both rate and magnitude from the peak of the swarm recorded during 9-11 March. More than 800 earthquakes, including multiple M2 and above events, were detected beneath Tanaga Island at depths less than 9 km below sea level during 11-17 March. The decline in activity decreased the potential for an eruption. Earthquake activity persisted through 20 March.

Tanaga – Andreanof Islands (USA) : AVO reported that earthquake activity near Tanaga had decreased in both rate and magnitude from the peak of the swarm recorded during 9-11 March. More than 800 earthquakes, including multiple M2 and above events, were detected beneath Tanaga Island at depths less than 9 km below sea level during 11-17 March. The decline in activity decreased the potential for an eruption. Earthquake activity persisted through 20 March.

Volcanos

Roundup of Global Volcanic Activity – Ongoing activity for the week 8 March – 14 March 2023

Ahyi – Mariana Islands (USA) : Unrest at Ahyi Seamount continued during 8-14 March. A few events per day were detected by pressure sensors on Wake Island, 2,270 km E, during 7-11 March. Almost continuous hydroacoustic signals from roughly the direction of Ahyi were recorded by the sensors during 11-13 March, and then signals stopped abruptly on 14 March. Discolored water was visible in satellite images during 12-14 March; the discoloration extended about 35 km at the end of the week.

Aira – Kyushu (Japan) : JMA reported ongoing eruptive activity at Minamidake Crater and Showa Crater (at Aira Caldera’s Sakurajima volcano) during 6-13 March. Incandescence at Minamidake was visible nightly. Five eruptive events at Minamidake were recorded and explosions occurred on 8 and 11 March. Ash plumes rose as high as 1.7 km above the crater rim, and during 10-13 March large blocks were ejected as far as 500 m from the vent. Seven eruptive events occurred at Showa during 6-10 March, producing ash plumes that rose as high as 2.7 km above the crater rim and ejecting large blocks 800 m from the crater.

Chiles-Cerro Negro – Colombia-Ecuador : A seismic swarm at the Cerro Negro de Mayasquer and Chiles volcanoes, called the Chiles-Cerro Negro volcanic complex (CCNVC), began on 9 March according to the Instituto Geofísico de la Escuela Politécnica Nacional (IGEPN) and the Observatorio Vulcanológico de Pasto (OVP-Colombia). A noted increase in the intensity of seismic signals occurred at 0430 and was followed by an increase in the number of volcano-tectonic events (indicating fracturing rock) at 0900. By 1630, there were around 2,200 earthquakes recorded by the seismic network, and 520 of those events had epicenters located within 2.5 km S of Chiles at depths of 1-6 km below the summit (4,700 m elevation). The swarm was accompanied by deformation which was first detected on 28 February. The swarm intensified during 9-10 March, and 86 earthquakes were above M2. At 2010 on 9 March a M 3.4 earthquake was felt by residents in nearby towns in both Colombia and Ecuador; earthquakes recorded at 0137 and 0526 on 10 March were also felt. On 10 March earthquakes were occurring at a rate of around 200 events per hour and were mostly comprised of volcano-tectonic events (indicating fracturing rock) and very-low-frequency earthquakes (indicating fluid movement). At least 4,500 events had been recorded by 1214 on 10 March. There were 4,244-4,915 daily earthquakes during 11-13 March.

Cotopaxi – Ecuador : IG reported that the eruption at Cotopaxi continued during 8-14 March. Gas-and-steam emissions were visible on most days rising as high as 1.5 km above the crater rim and drifting in multiple directions. On 10 March a gas-and-steam plume with low ash content rose as high as 1 km and drifted S. Weather clouds sometimes prevented observations, especially on 11 March.

Ebeko – Paramushir Island (Russia) : KVERT reported that moderate activity at Ebeko was ongoing during 2-9 March. According to volcanologists in Severo-Kurilsk (Paramushir Island, about 7 km E) explosions during 3, 5-7, and 9 March generated ash plumes that rose as high as 3.6 km (11,800 ft) a.s.l. and drifted E. A thermal anomaly was identified in satellite images on 7 and 9 March. Ashfall was reported in Severo-Kurilsk on 3 March.

Great Sitkin – Andreanof Islands (USA) : AVO reported that slow lava effusion at Great Sitkin likely continued during 8-14 March. Satellite images and web camera views were mostly cloudy, though elevated surface temperatures were identified in satellite images during 8-9 March. Seismicity was low.

Krakatau – Sunda Strait : The Darwin VAAC reported that during 1240-1300 on 10 March continuous ash emissions from Anak Krakatau rose 1.5-1.8 km (5,000-6,000 ft) a.s.l. and drifted W and NW based on satellite images, weather models, and PVMBG webcams. Only steam-and-gas emissions were visible on webcam images on 11 March.

Lewotolok – Lembata Island : PVMBG reported that the eruption at Lewotolok was ongoing during 8-14 March. Daily white gas-and-steam plumes rose as high as 700 m above the summit and drifted in multiple directions. A few webcam images posted with the observatory reports showed incandescence at the summit.

Sabancaya – Peru : Instituto Geofísico del Perú (IGP) reported moderate levels of activity at Sabancaya during 27 February-5 March with a daily average of 46 explosions. Gas-and-ash plumes rose as high as 2.6 km above the summit and drifted NW, W, and SW. Four thermal anomalies originating from the lava dome in the summit crater were identified in satellite data.

San Miguel – Eastern El Salvador : MARN reported increased emissions at San Miguel during 7-9 March. Gas emissions began increasing along with seismicity at 2252 on 7 March and were continuous at least through the morning of 8 March. A total of 12 emissions were recorded, with the last one occurring at 1210 on 9 March. Some of the gas emissions contained ash, with the most intense period causing minor ashfall in El Tránsito (10 km S), La Morita (6 km W), and La Piedrita (3 km W), and a sulfur odor in Piedra Azul (5 km SW).

Semeru – Eastern Java : PVMBG reported that the eruption at Semeru continued during 8-14 March. Weather clouds sometimes prevented views of the volcano, though ash plumes were visible each day. On 8 March white-and-gray ash plumes that were sometimes dense rose as high as 300-700 m above the summit and drifted N and NE. During 9-10 March dense white, gray, and brown ash plumes rose 500-600 m and drifted SW and S. At least six white-and-gray ash plumes of variable densities were visible on 11 March rising 600-800 m and drifting N, W, and S. White-and-gray ash plumes rose 500-700 m and drifted N, NE, and SW during 12-14 March.

Sheveluch – Central Kamchatka (Russia) : 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 2-9 March and ash plumes drifted as far as 118 km E during 4-5 March.

Suwanosejima – Ryukyu Islands (Japan) : JMA reported that the eruption at Suwanosejima’s Ontake Crater continued during 6-13 March. A total of 18 explosions were recorded, sending ash plumes as high as 2.3 km above the crater rim and ejecting large blocks as far as 400 m from the vent. Crater incandescence was visible at night. Occasional ashfall was reported in Toshima village (3.5 km SSW). On 8 March grayish-white plumes were seen rising from the vent during an overflight. No other changes were noted compared to the last overflight conducted on 29 September 2022.

Villarrica – Central Chile : SERNAGEOMIN reported that the eruption at Villarrica was ongoing during 8-14 March. Webcam images on 13 March showed incandescence above the crater rim from Strombolian activity.

Whakaari/White Island – North Island (New Zealand) : On 10 March GeoNet reported continuing unrest at Whakaari/White Island characterized by significant gas-and-steam emissions and increasing gas emissions. Significant amounts of steam and gas at temperatures of around 240 degrees Celsius were measured during an observation flight on 2 March and a gas flight on 9 March. Gas emissions had increased but remained within normal limits. Large steam plumes, which were likely enhanced due to weather conditions, were visible from the mainland rising above the volcano on 5 March. Significant rain during the previous month raised the water levels in the crater lake and some of the smaller pools; geysering and bubbling from underwater fumaroles was visible.

Volcanos

Roundup of Global Volcanic Activity – New activity for the week 8 March – 14 March 2023

Karangetang – Sangihe Islands : Webcam images of Karangetang posted in PVMBG daily reports showed very minor incandescence at the summit Main Crater (S crater) during 8-14 March. Short, dimly incandescent trails on images from 8 and 10 March were possibly from avalanches. According to the Darwin VAAC at 1710 on 9 March an ash plume rose to 2.4 km (8,000 ft) a.s.l. and drifted S. A large thermal anomaly was visible in images from 0550 and 0930 on 10 March.

Merapi – Central Java : BPPTKG reported that the eruption at Merapi (on Java) continued during 3-9 March and seismicity remained at high levels. The SW lava dome produced 19 lava avalanches that traveled as far as 1.7 km down the SW flank (upstream in the Bebeng, Boyong, and Sat/Putih drainages). No significant morphological changes to the central and SW lava domes were evident in webcam images. Activity increased on 11 March with collapses of the SW lava dome. During 1212-1500 a series of 21 lava avalanches from the SW lava dome produced pyroclastic flows that traveled less than 4 km down the Bebeng and Krasak drainages. Ash plumes rose from the dome and in dense “curtains” from along the pyroclastic-flow deposits on the SW flank. The ash plumes rose as high as 3 km above the summit during 1212-1306 and drifted W and NW, causing ashfall in several areas downwind, especially in Magelang. Avalanches and pyroclastic flows from additional collapses continued to be recorded on 12 March. A total of 15 avalanches descended the SW flank as far as 2.5 km and 21 pyroclastic flows traveled a maximum distance of 2 km SW. White-and-gray ash plumes of variable densities rose as high as 2.5 km above the summit and drifted N, NW, W, and E based on Darwin VAAC notices and PVGHM VONAs. A drone was deployed to inspect the SW dome and flank, the deposits, and the summit dome; the end of the pyroclastic-flow deposits in the Bebeng drainage was 3.7 km from the center of the summit crater. By early on 13 March a total of 60 pyroclastic flows had been mainly channeled down the Bebeng. On 13 March there was a total of 36 lava avalanches; two pyroclastic flows went as far as 1.5 km down the SW flank. The Darwin VAAC reported that at 0100, 0630, and 0900 ash plumes rose as high as 4.3 km (14,000 ft) a.s.l., or 1.4 km above the summit, and drifted NW. A VONA issued on 14 March described a gray-and-brown ash plume that rose 2.5 km above the summit and drifted E and SE.

Nyamulagira – DR Congo : The Observatoire Volcanologique de Goma (OVG) reported increased activity at Nyamulagira on 13 March. Seismicity indicated magma movement at shallow depths towards the central part of the crater and incandescence above the crater rim was visible beginning at around 1800. The Toulouse VAAC reported at 1130 on 14 March that lava fountains were observed, and an eruption plume rose 1.5 km above the crater rim, based on information from OVG. The VAAC noted that the plume was not identified in satellite images due to weather cloud cover.

Takawangha – Andreanof Islands (USA) : AVO reported that the earthquake swarm at Takawangha that began in November 2022 started to decline on 1 March. Seismicity abruptly increased again on 8 March and was sustained, with M4 or lower earthquakes occurring at depths of less than about 6 km below sea level. Earthquake activity beneath Takawangha volcano and nearby Tanaga Volcano (8 km W), both on Tanaga Island, continued at a high rate during 8-9 March, with more than 100 events per hour at times. Sustained seismicity indicated an increased potential for an eruption. Earthquakes beneath Tanaga and Takawangha occurred at a rate of up to several events per minute during 10-11 March and at a slightly reduced rate during 12-14 March. The earthquakes had magnitudes up to about 4 and were mostly occurring at depths less than about 6 km.

Tanaga- Andreanof Islands (USA) : AVO reported that earthquake activity near Tanaga began to increase on 4 March with events up to the M2 range and located 9-18 km deep. Seismicity again increased around 1330 on 7 March and by 2045 earthquakes were occurring at a rate of 2-3 per minute. AVO raised the Aviation Color Code to Yellow (the second lowest level on a four-color scale) and the Volcano Alert Level to Advisory the second lowest level on a four-level scale). The seismicity was sustained during 8-9 March and had shallowed to depths less than about 6 km, indicating increased potential for an eruption. Seismicity was also elevated at Takawangha, 8 km E; both volcanoes are located on Tanaga Island. Earthquakes beneath Tanaga Island occurred at a rate of up to several per minute, with the largest event during 8-9 March, a M3.9, located under Tanaga Volcano. Earthquakes beneath Tanaga and Takawangha occurred at a rate of up to several events per minute during 10-11 March and at a slightly reduced rate during 12-14 March. The earthquakes had magnitudes up to around 4.

Volcanos

Roundup of Global Volcanic Activity – Ongoing activity for the week 1 March – 7 March 2023

Ahyi – Mariana Islands (USA) : Unrest at Ahyi Seamount continued during 1-7 March. Plumes of discolored water above the seamount were visible in satellite images during 1-2 and 4 March. Pressure sensors on Wake Island, 2,270 km E of Ahyi Seamount, did not detect activity.

Aira – Kyushu (Japan) : JMA reported ongoing eruptive activity at Minamidake Crater and Showa Crater (at Aira Caldera’s Sakurajima volcano) during 27 February-6 March. Incandescence was visible nightly at Minamidake and during 3-6 March at Showa. Explosions at Minamidake were recorded on 28 February and 1, 3, and 4 March, and non-explosive eruptive events were occasionally recorded. Eruption plumes rose as high as 2.8 km above the Minamidake Crater rim and large blocks were ejected as far as 1.3 km from the vent. Non-explosive eruptive events were occasionally recorded at Showa during 27 February-2 March and four explosions occurred during 3-6 March. Eruption plumes rose as high as 2.7 km above the Showa rim and large blocks were ejected 500-800 m from the vent. Sulfur dioxide emissions were extremely high at 3,500 tons per day on 2 March.

Cotopaxi – Ecuador : IG reported that the eruption at Cotopaxi continued during 28 February-7 March. Several daily ash, gas, and steam plumes rose as high as 1.5 km above the summit during 28 February-2 March and drifted W and SW. Minor ashfall was reported in Mulaló parish (Colcas-Ticatilín) of the Latacunga canton during the afternoon of 28 February. Steam-and-gas emissions were visible rising as high as 700 m and drifting SW and W during 3-7 March. Minor ashfall was reported in Mulaló parish on 5 March.

Dieng Volcanic Complex – Central Java : On 6 March PVMBG lowered the Alert Level for the Dieng Volcanic Complex to 1 (on a scale of 1-4) due to decreased carbon dioxide emissions. During the first half of January carbon dioxide emissions were elevated at Timbang Crater and then significantly increased in mid-January; recent measurements indicated a decreasing trend. On 22 February a mobile instrument measured 112,000 ppm CO2 at the crater, though the concentration dropped to 9,200 ppm at a distance of less than 10 m from the crater rim. Measurements at the multi-gas station indicated concentration of 1,500-1,900 parts per million (ppm).

Ebeko – Paramushir Island (Russia) : KVERT reported that moderate activity at Ebeko was ongoing during 23 February-2 March. According to volcanologists in Severo-Kurilsk (Paramushir Island, about 7 km E) explosions during 24 and 26-27 February and on 2 March generated ash plumes that rose as high as 4 km (13,100 ft) a.s.l. and drifted E. Ashfall was reported in Severo-Kurilsk on 27 February.

Great Sitkin – Andreanof Islands (USA): AVO reported that slow lava effusion at Great Sitkin likely continued during 1-7 March. Satellite images and web camera views were cloudy. Seismicity was low.

Kilauea – Hawaiian Islands (USA) : HVO reported that the eruption on the floor of Kilauea’s Halema’uma’u Crater continued during 1-6 March but at a decreased rate. The western lake in the basin of the 2021-2022 lava lake remained weakly active; a few lava flows were visible on 1 March. A small amount of lava circulated within the lake and there were intermittent crustal overturns, but the lake was mostly crusted over and the active area got substantially smaller through the week; by 5 March the lake was completely crusted over. Minor lava ooze outs were visible on 6 March, and the eruption had paused by 7 March.

Lewotolok – Lembata Island : PVMBG reported that the eruption at Lewotolok was ongoing during 1-7 March. White-and-gray plumes rose as high as 400 m above the summit and drifted E and SE on 2 and 7 March. On most of the other days white gas plumes were seen rising as high as 100 m and drifting E and SE.

Marapi – Central Sumatra : PVMBG reported that the eruption at Marapi (on Sumatra) continued during 1-7 March. On 2 March white steam-and-gas plumes rose 100 m from the summit and drifted NW, SW, and E, and on 4 March white-and-gray plumes rose 200 m and drifted N and NE; weather clouds prevented visual observations on the other days.

Merapi – Central Java : BPPTKG reported that the eruption at Merapi (on Java) continued during 24 February-2 March and seismicity remained at high levels. The SW lava dome produced two lava avalanches that traveled as far as 1 km down the SW flank (upstream in the Bebeng and Boyong drainages). No significant morphological changes to the central and SW lava domes were evident in webcam images.

Nevado del Ruiz – Colombia : Servicio Geológico Colombiano (SGC) reported that seismicity at Nevado del Ruiz began increasing on 27 February characterized by events indicting fluid movement. The elevated seismicity was sustained. On 4 March the intensity of the signals intensified and were associated with mostly continuous ash emissions with occasional pulses. Ashfall was reported in Manizales (27 km NW).

Papandayan – Western Java : PVMBG issued a special report based on recent observations of Papandayan. The number of shallow volcanic earthquakes had increased in January and although the numbers fluctuated, low-frequency earthquakes also increased overall during January and February. Webcam images from the camera in the parking area showed incandescence emanating from Kawah Baru during the night on 22 February. A team of PVMBG scientists inspected the crater during 2100-2300 on an unspecified date to identify the source of the incandescence. They observed intense emissions rising from Kawah Baru, heard faint rumbling, and detected a strong sulfur odor, but did not see incandescence. Gas plumes rose 300 m from a solfatara. The color of the lake in Kawah Baru was greenish. Rumbling sounds from both the Kawah Mas and Kawah Baru solfatara complexes varied from weak to strong and gas emissions were sometimes intense. Solfatara temperatures were variable at Kawah Mas, Kawah Manuk, and Kawah Baru with a maximum temperature of 123.8 degrees Celsius. Sulfur dioxide gas concentrations were high at a distance of 500 m from the solfatara complexes. Based on the field observations PVMBG concluded that conditions at Papandayan were relatively normal.

Semeru – Eastern Java : PVMBG reported that the eruption at Semeru continued during 1-7 March. Weather clouds sometimes prevented views of the volcano, though on most days no emissions were visible. On 6 March white-and-gray ash plumes rose as high as 200 m above the summit and drifted N and NE.

Sheveluch – Central Kamchatka (Russia) : 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 23 February-2 March. At 1150 on 5 March local time video images showed an ash plume generated by hot avalanches rising 5.5 km a.s.l. (just over 2.2 km above the summit) and drifting 5 km NE.

Takawangha – Andreanof Islands (USA) : AVO reported that the earthquake swarm at Takawangha that began in November 2022 was ongoing with 120 earthquakes located during 25 February-3 March. The number of events per day was highest on 28 February and 1 March, with over 50 earthquakes located on each of those days. Three earthquakes had magnitudes greater than 3, occurred at shallow depths of less than 6 km, and were located about 6 km E of the volcano. During 3-7 March small daily earthquakes with magnitudes less than M2 occurred in the vicinity of the volcano.

Volcanos

Roundup of Global Volcanic Activity – New activity for the week 1 March – 7 March 2023

Aniakchak – Alaska Peninsula, Alaska : AVO reported that the earthquake swarm at Aniakchak was ongoing with 120 earthquakes located during 25 February-3 March. Magnitudes were as high as M3.1 and several earthquakes had magnitudes between M2 and M3. The earthquakes were located at shallow depths (less than 5 km) and below the S part of the caldera and to the E of the volcano. Daily, small, shallow earthquakes with magnitudes as high as M2.7 were recorded during 4-7 March.

Karangetang – Sangihe Islands : According to PVMBG the eruption at Karangetang’s Main Crater (S crater) continued during 1-7 March. Nighttime webcam images posted with daily reports showed flows of incandescent material descending the flanks, though incandescence decreased towards the end of the week.

Suwanosejima – Ryukyu Islands (Japan) : JMA reported that the number of explosions at Suwanosejima’s Ontake Crater began to increase on 2 February and further increased on 2 March. Activity intensified and a total of 25 explosions were recorded during 1-5 March. Ash plumes rose as high as 1.4 km above the crater rim and large blocks were ejected as far as 500 m from the vent. Crater incandescence was visible at night. Occasional ashfall and rumbling noises were reported in Toshima village (3.5 km SSW). Explosions continued during 5-7 March. Ash plumes rose as high as 2 km above the crater rim and large blocks were ejected as far as 500 m.

Tanaga – Andreanof Islands (USA) : At 2215 on 7 March AVO raised the Aviation Color Code for Tanaga to Yellow and the Volcano Alert Level to Advisory due to increased seismicity. Earlier that afternoon, starting at about 1330, seismicity began to increase and by around 2045 earthquakes were occurring at a rate of 2-3 per minute. The events were located at shallow depths and the largest events were M2-3.

Trident – Alaska : AVO reported that the earthquake swarm at Trident was ongoing during 1-7 March. Daily small earthquakes with magnitudes less than 1 were recorded at a rate of about 1-5 per day. 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).

Volcanos

Roundup of Global Volcanic Activity – Ongoing activity for the week 22 February – 28 February 2023

Ambae – Vanuatu : On 23 February the Vanuatu Meteorology and Geo-Hazards Department (VMGD) reported that the cone in Ambae’s Lake Voui continued to produce emissions consisting of steam, volcanic gases, and possibly occasional ash that drifted downwind. Volcanic earthquakes were recorded by the seismic network.

Bezymianny – Central Kamchatka (Russia) : KVERT reported that during 17-23 February a daily thermal anomaly over Bezymianny was identified in satellite images.

Cotopaxi – Ecuador : IG reported that the eruption at Cotopaxi continued during 22-28 February, characterized by almost daily emissions of gas, steam, and ash; inclement weather conditions occasionally prevented views. Gas-and-steam emissions rose 500 m above the crater rim and drifted W during 21-22 February. Weather clouds prevented visual observations of the volcano during most of 23 February, though by the late afternoon and into the next morning steam emissions with low ash content were seen rising 500 m and drifted SW. Gas-and-steam plumes rose 500 m and drifted W on 25 February. Several emissions of gas, steam, and ash rose as high as 2.4 km and drifted SE on 26 February. During periodic breaks in weather clouds, continuous emissions of gas, steam, and ash sere seen rising as high as 1.5 km and drifting E and SE. Minor amounts of ash fell in the province of Pichincha in Rumiñahui (61 km N), Rumipamba Vallecito, Conocoto (41 km N), El Pedregal (60 km N), Guamaní (42 km NNW), Quitumbe (41 km NNW), La Ecuatoriana (44 km NNW), Chillogallo (47 km NNW), Urubamba (Santo Tomas, 40 km NNW), La Magdalena (Barrio Nuevo, Villaflora, 48 km NNW) and San Bartolo. At 1430 on 28 February an ash plume rose 500 m and drifted SW.

Ebeko – Paramushir Island (Russia) : KVERT reported that moderate activity at Ebeko was ongoing during 16-23 February. A thermal anomaly was identified in satellite images on 21 February. According to volcanologists in Severo-Kurilsk (Paramushir Island, about 7 km E) explosions on 22 February generated ash plumes that rose as high as 3 km (10,000 ft) a.s.l. and drifted E.

Fuego – South-Central Guatemala : INSIVUMEH reported that 4-10 explosions per hour were recorded at Fuego during 22-28 February, generating ash plumes that rose as high as 1.1 km above the crater rim and drifted as far as 30 km NW, W, and SW. Weather clouds often prevented visual observations on 22 February. Explosions ejected incandescent material 100-400 m above the summit each day, and daily shock waves rattled structures in communities around the volcano. Daily block avalanches descended various drainages including the Ceniza (SSW), Seca (W), Trinidad (S), Taniluyá (SW), Honda, Las Lajas (SE), and El Jute (ESE), and often reached vegetated areas. Ashfall was recorded almost daily in areas downwind including Morelia (9 km SW), Panimaché I and II (8 km SW), Santa Sofía (12 km SW), Sangre de Cristo (8 km WSW), El Porvenir (8 km ENE), San Pedro Yepocapa (8 km NW), Finca la Asunción, Finca Palo Verde, and La Soledad (11 km N).

Great Sitkin – Andreanof Islands (USA) : AVO reported that slow lava effusion at Great Sitkin was confirmed by recent satellite images. A radar image from 19 February showed advancement of the E lobe of the flow field. Additionally, a smaller lobe to the S was advancing towards the crater rim where lava previously spilled down the SW flank in 2021-2022. Lava effusion in the summit crater was visible in 24 and 26 February satellite images. Seismicity was very low 22-28 February with a few local earthquakes detected during 22-23 and 24-25 February. Weather cloud cover sometimes prevented webcam and satellite views.

Kerinci – Central Sumatra : PVMBG reported that the eruption at Kerinci was ongoing during 22-28 February. Weather clouds often prevented visual observations of the volcano. White-and-gray ash plumes rose 50-150 m above the crater rim and drifted W and E on 26 February. The next day white-and-brown ash plumes rose as high as 150 m and drifted W.

Kilauea – Hawaiian Islands (USA): HVO reported that the eruption on the floor of Kilauea’s Halema’uma’u Crater continued during 22-28 February but at a decreased rate. The E and central vents were not erupting. The western lake in the basin of the 2021-2022 lava lake remained active but with weak lava flows. A small amount of lava is circulating within the lake with intermittent crustal overturns; the lake is mostly crusted over.

Merapi – Central Java : BPPTKG reported that the eruption at Merapi (on Java) continued during 17-23 February and seismicity remained at high levels. The SW lava dome produced 11 lava avalanches that traveled as far as 1.7 km down the SW flank (upstream in the Bebeng and Boyong drainages). No significant morphological changes to the central and SW lava domes were evident in webcam images. An avalanche from the weathered and altered 1998 lava wall was visible in webcam images on 10 February.

Nyamulagira – DR Congo : The Observatoire Volcanologique de Goma (OVG) reported that the lava lake on Nyamulagira’s crater floor continued to be active during 13-19 February. Seismicity was generally low, characterized by a few long-period earthquakes located up to 15 km deep along the large fracture connecting the Nyamuragira and Nyiragongo. High concentrations of carbon dioxide were measured in the Mazuku areas, and in an area to the W of a camp in the Lac Vert district in Bulengo.

Nyiragongo – DR Congo : The Observatoire Volcanologique de Goma (OVG) reported that the lava lake on Nyiragongo’s crater floor continued to be active during 13-19 February; faint glow emanated from the crater on 15 February. Seismicity was generally low, characterized by a few long-period earthquakes located up to 15 km deep along the large fracture connecting the Nyamuragira and Nyiragongo. A seismic station near the volcano registered a minor increase in the intensity of signals on 17 February. High concentrations of carbon dioxide were measured in the Mazuku areas, and in an area to the W of a camp in the Lac Vert district in Bulengo.

Santa Maria – Southwestern Guatemala : INSIVUMEH reported that the eruption at Santa María’s Santiaguito lava-dome complex continued during 22-28 February. Effusion from Caliente dome fed lava flows that slowly descended the San Isidro and Zanjón Seco drainages on the W and SW flanks. Incandescence from the dome and the lava flows was visible nightly. Block-and-ash flows from the dome, and from both the ends and sides of the flows, descended the S, SW, and W flanks almost daily. Ash plumes from the avalanches and from occasional explosions at the summit rose a few hundred meters high; during 22-23 February ash plumes rose 700 m above the summit and drifted WNW.

Semeru – Eastern Java : PVMBG reported that the eruption at Semeru continued during 22-28 February. Dense white-and-gray ash plumes rose 300-1,000 m above the summit and drifted N, NE, and E on 22 February. Weather conditions mostly prevented visual observations during the rest of the week, though at 0705 on 23 February a dense white-and-gray ash plume was seen rising to 1 km and drifting SE. The seismic network recorded an eruptive event at 0404 on 26 February; no emissions were observed.

Sheveluch – Central Kamchatka (Russia) : 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 February. During a field visit to the volcano on 25 February Kamchatka Volcano Station scientists observed and photographed the dome and saw incandescent debris avalanches on the originating at the dome’s summit.

Stromboli – Aeolian Islands (Italy) : INGV reported that both explosive and effusive activity at Stromboli occurred during 20-26 February at two vents in Area N, within the upper part of the Sciara del Fuoco, and at least two vents in the Area C-S (South-Central Crater area) in the crater terrace area. Explosions at vents N1 and N2 in Area N were variable in intensity and ejected coarse material (bombs and lapilli) 80-150 m at a rate of 2-7 explosions per hour. Spattering occasionally occurred at N2 vents during 20-24 February and was sometimes intense. Explosive activity at S2 in the Central-South area (CS) ejected fine-to-coarse material as high as 150 m above the vent at a rate of 1-7 explosions per hour. At around 0700 on 27 February lava overflowed vents in Area N and produced lava flows and at around midnight intense spattering in the same area was visible. Spattering continued at least through 2100 on 28 February; the lava flows were cooling, though some areas were hot due to accumulated material.

Suwanosejima – Ryukyu Islands (Japan) : JMA reported that the eruption at Suwanosejima’s Ontake Crater continued during 20-27 February. A total of 20 explosions were recorded, sending ash plumes as high as 2 km above the crater rim and ejecting large blocks as far as 400 m from the vent. Crater incandescence was visible at night. Occasional ashfall and rumbling noises were reported in Toshima village (3.5 km SSW).

Villarrica – Central Chile : The eruption at Villarrica was ongoing during 22-28 February. Low-intensity gas emissions rose from the crater on 22 February. Long-period earthquakes recorded at 1056 and 1301 on 27 February were associated with ash plumes that rose 300 m above the crater rim. Several additional minor ash emissions were visible during 1056-1320. The Alert Level remained at Yellow (the second lowest level on a four-color scale) according to SERNAGEOMIN.

Yasur – Vanuatu : On 23 February the Vanuatu Meteorology and Geohazards Department (VMGD) reported that activity at Yasur continued at a high level of “major unrest,” as defined by the Alert Level 2 status (the middle level on a scale of 0-4). Recent observations confirmed that low-to-moderate explosions continued, ejecting bombs that landed back into the crater and producing ash, gas, and steam emissions. The larger explosions occasionally ejected material outside of the crater.

Volcanos

Roundup of Global Volcanic Activity – New activity for the week 22 February – 28 February 2023

Aira – Kyushu (Japan) : JMA reported ongoing eruptive activity at Minamidake Crater and Showa Crater (at Aira Caldera’s Sakurajima volcano) during 13-20 February and incandescence at both craters was visible nightly. Very small eruptive events occurred at Showa Crater. Three explosions and three or four eruptive events were recorded at Minamidake Crater during the week. Volcanic plumes rose as high as 1.5 km above the Minamidake Crater rim and large blocks were ejected 600-900 m from the vent. During an overflight on 21 February scientists observed white plumes rising from a vent on the N inner crater wall at Showa Crater and they noted more voluminous emissions compared to the 12 October 2022 overflight. No notable changes at Minamidake Crater were observed. At 1230 on 26 February an eruptive event at Minamidake Crater produced a plume that rose 1.2 km above the crater rim.

Aniakchak – Alaska Peninsula, Alaska : On 22 February AVO raised the Aviation Color Code for Aniakchak to Yellow (the second lowest level on a four-color scale) and the Volcano Alert Level to Advisory (the second lowest level on a four-level scale) due to a recent increase in the number of earthquakes and a shallowing of those events. Background seismicity was generally characterized as deep (more than 15 km below sea level) long-period events occurring at a rate of about four events per month. Beginning in October 2022 the rate increased, and the earthquakes were located at depths less than 9 km below sea level. The earthquake rate further increased on 31 January and was sustained with dozens of earthquakes detected per day, including a M 3.7 earthquake recorded on 17 February. Elevated seismicity continued during 23-27 February at a variable rate. Dozens of earthquakes were recorded daily during 22-26 February, though more than one hundred small earthquakes (not all locatable) were detected during 24-25 February. Small earthquakes occurred at the rate of about 10 per hour during 26-28 February. AVO noted that there was no indication that an eruption of Aniakchak was imminent, or that one will occur. Increases in seismic activity have been detected previously at other similar volcanoes, with no subsequent eruptions.

Epi – Vanuatu : On 23 February the Vanuatu Meteorology and Geo-Hazards Department (VMGD) reported that minor unrest continued at Epi. Seismicity was sustained though there was only minor manifestation at the water’s surface; steaming at the surface lasting only a few hours at most was occasionally observed.

Karangetang – Sangihe Islands : According to PVMBG the eruption at Karangetang’s Main Crater (S crater) continued during 22-28 February. Nighttime webcam images posted with daily reports showed incandescent lava flows descending the flanks, though images from 0054 on 26 February and 0026 on 1 March showed only minor incandescence near the summit. The Darwin VAAC reported that during 22-23 February ash plume rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted SE based on analyses of satellite imagery and weather models.

Trident – Alaska : An earthquake swarm at Trident began on 24 August 2022 and within about four days the seismic network began detecting episodes of weak seismic tremor and low frequency earthquakes. The events were initially located at depths around 25 km, but then they progressively shallowed to around 5 km by 28 August. AVO attributed the swarm to moving magma or magmatic fluids and noted that seismic swarms had previously been recorded with no subsequent eruptions. Beginning on 1 January 2023 seismicity again increased with earthquakes occurring at an average rate of about ten per day at depths less than 6 km. The elevated seismicity was sustained. Dozens of small earthquakes were recorded daily during 23-28 February; the largest event, a M4, was recorded during the morning of 24 February. Trident last erupted during 1953-1974.

Volcanos

Roundup of Global Volcanic Activity – Ongoing activity for the week 15 February – 21 February 2023

Cotopaxi – Ecuador : IG reported that the eruption at Cotopaxi continued during 14-21 February, characterized by almost daily emissions of gas, steam, and ash; inclement weather conditions occasionally prevented views. Gas emissions with some ash rose as high as 600 m above the crater rim and drifted E, SE, and SW during 14-15 February. Minor ashfall was noted in San Ramón (17 km SW), Ticatilín (15 km WSW), San Agustín del Callo (18 km WSW), Mulaló (19 km SW), and Lasso (20 km WSW). Daily ash-and-gas plumes rose as high as 1.1 km during 16-19 February and drifted mainly E, SE, S, and SW. Minor amounts of ash occasionally fell on the downwind flanks. During 20-21 February steam-and-gas plumes rose as high as 1.3 km and drifted E and SW.

Ebeko – Paramushir Island (Russia) : KVERT reported that moderate activity at Ebeko was ongoing during 9-16 February. According to volcanologists in Severo-Kurilsk (Paramushir Island, about 7 km E) explosions during 9 and 12-13 February generated ash plumes that rose as high as 4 km (13,100 ft) a.s.l. and drifted NE and E. A thermal anomaly was identified in satellite images on 9 and 13 February, and an ash cloud drifted 45 km E on 12 February.

Etna – Sicily (Italy) : INGV reported that lava effusion had ended on 6 February from the vents at the NE base of Etna’s SE Crater, in the Valle del Leone at about 2,800 m elevation. The total area covered by the lava flows was an estimated 0.96 square kilometers and the estimated volume was 4,800,000-6,100,000 cubic meters.

Great Sitkin – Andreanof Islands (USA) : AVO reported that a 15 February satellite image confirmed continuing lava effusion at Great Sitkin and growth of the flow field to the E, though effusion likely continued through 20 February. Weather clouds often obscured satellite and webcam views; steam emissions were observed during 17-18 February and weakly elevated surface temperatures were identified in satellite images during 19-20 February. Seismicity was very low during 21-22 February with one small local earthquake detected.

Kerinci – Central Sumatra : PVMBG reported that the eruption at Kerinci was ongoing during 15-20 February. Ash plumes of variable densities were visible during 15-16 and 18 February rising as high as 250 m above the summit and drifting mainly NE, E, and W. White steam-and-gas plumes were visible on the other days. At 1207 on 15 February a dense brown ash plume rose 200 m and drifted E. At 0908 on 16 February a dense brown ash plume rose 250 m and drifted E, and at 1937 a gray-to-brown ash plume rose 150 m that drifted E and SE.

Kilauea – Hawaiian Islands (USA) : HVO reported that the eruption on the floor of Kilauea’s Halema’uma’u Crater continued during 15-21 February but at a decreased rate during the last half of the week. Lava erupted from three locations during 15-17 February. The lava lake in E half of the crater was active, had a small lava fountain, and remained at about 10 hectares in size; the smaller western lake in the basin of the 2021-2022 lava lake was also active. The smaller lava pond in the central portion of the crater floor had a small lava fountain, produced nearly continuous overflows, and channeled lava to the E lake. Activity in the E and central lakes diminished in the late afternoon on 17 February, and by 18 February both had stopped erupting. The western lake was active but at a greatly reduced level and lava only minimally circulated; the lake was mostly crusted over and about 10 m lower by 19 February. The lake produced small lava flows and intermittent crustal overturns during 19-20 February.

Lewotolok – Lembata Island : PVMBG reported that the eruption at Lewotolok was ongoing during 15-21 February. Minor crater incandescence at the summit was visible in most of the nighttime webcam images posted with the daily PVMBG reports. A webcam image captured at 0210 on 18 February showed Strombolian activity and incandescent material on the flank. White-and-gray plumes rose as high as 400 m above the summit and drifted E and SE during 16-17 February. A white-and-gray plume rose 700 m and drifted E on 19 February.

Marapi – Central Sumatra : PVMBG reported that the eruption at Marapi (on Sumatra) continued during 15-21 February. White steam-and-gas plumes were visible almost daily rising as high as 100 m from the summit; weather clouds prevented visual observations on 16 February. White-and-gray ash plume rose around 500 m from the summit and drifted E, SE, and SW on 20 February.

Merapi – Central Java : BPPTKG reported that the eruption at Merapi (on Java) continued during 10-16 February and seismicity remained at high levels. The SW lava dome produced two lava avalanches that traveled as far as 1.7 km down the SW flank (upstream in the Kali Sat drainage). No significant morphological changes to the central and SW lava domes were evident in webcam images.

Popocatepetl – Mexico : CENAPRED reported that there were 102-215 steam-and-gas emissions, often containing ash, rising from Popocatépetl each day during 14-21 February; minor explosions also occurred almost daily. Minor explosions were recorded at 1334, 1456, and 1822 on 14 February and at 0253 on 15 February based on data from the seismic network. On 17 February minor explosions occurred at 0210, 1827, 2210, 2252, and 2325. Additional minor explosions were recorded at 0235, 0252, and 0614 on 18 February; a webcam image from 0236 showed ejected incandescent material on the flanks. The lava dome on the crater floor was visible in satellite images and hadn’t significantly changed since the 27 January overflight. On 20 February a minor explosion was recorded at 1805, and a moderate explosion at 2331 ejected incandescent material onto the upper flanks. A series of five minor explosions were recorded at 0027, 0052, 0252, 0401, and 0529 on 21 February. Ash fell in Amecameca (19 km NW), in the State of Mexico, during 20-21 February.

Reventador – Ecuador : IG described the ongoing eruption at Reventador as moderate during 14-21 February. Seismicity was characterized by explosions, long-period earthquakes, periods of harmonic tremor, and signals that indicated emissions. Steam, gas, and ash plumes were observed in IG webcam images and described in Washington VAAC volcanic activity notifications during 14-19 February; weather conditions occasionally prevented views. The plumes rose as high as 1.6 km above the summit and drifted in multiple directions. A lava flow on the NE flank was visibly active during 14-15 February. Crater incandescence was visible almost nightly and incandescent blocks were seen rolling as far as 800 m down the flanks in all directions during the beginning of the week. Weather clouds prevented visual observations of the volcano during 20-21 February.

Sabancaya – Peru : Instituto Geofísico del Perú (IGP) reported moderate levels of activity at Sabancaya during 13-19 February with a daily average of 51 explosions. Gas-and-ash plumes rose as high as 2.6 km above the summit and drifted in multiple directions. Four thermal anomalies originating from the lava dome in the summit crater were identified in satellite data.

Sangay – Ecuador : IG reported a high level of activity at Sangay during 14-21 February, which included daily explosions, long-period earthquakes, periods of tremor, and gas, steam, and ash emissions. The daily count of explosions ranged from 30-56, though the daily seismic data transmission was sometimes interrupted. Almost daily gas, steam, and ash plumes were either observed in IG webcam images or described in Washington VAAC volcanic activity notifications; weather clouds often prevented observations of the summit. The plumes rose as high as 1.8 km above the volcano and drifted mainly E, SE, and W. Multiple thermal anomalies were identified in satellite images on most days. Incandescence from the crater, a 500-m-long lava flow on the SE flank, and rolling blocks were visible during the nights of 14-15 and 18-19 February.

Semisopochnoi – Aleutian Islands (USA) : AVO reported that seismicity at Semisopochnoi’s Mount Young was low during 14-21 February, and steam emissions were visible in webcam images almost daily. AVO noted that no significant tremor, ash emissions, or explosive activity had been recorded since late January.

Sheveluch – Central Kamchatka (Russia) : KVERT reported that the ongoing eruption at Sheveluch during 9-16 February was generally characterized by explosions, hot avalanches, lava-dome extrusion, and strong fumarolic activity. A daily thermal anomaly was identified in satellite images.

Suwanosejima – Ryukyu Islands (Japan) : JMA reported that the eruption at Suwanosejima’s Ontake Crater continued during 13-20 February. Occasional ashfall and rumbling noises were reported in Toshima village (3.5 km SSW). The number of explosions per day increased on 13 February and then gradually decreased beginning on 16 February; a total of about 24 explosions occurred during the week. At 2131 on 15 February an explosion produced an ash plume that rose 1.3 km above the crater rim and ejected large blocks as far as 900 m SE. An explosion around an hour later, at 2237, ejected large blocks as far as 700 m SE. During 18-20 February explosions produced ash plumes that rose as high as 2 km above the crater rim and ejected large blocks as far as 400 m from the vent. Crater incandescence was visible at night.

Villarrica – Central Chile : The eruption at Villarrica was ongoing during 15-21 February. POVI reported that on 17 February Strombolian explosions ejected material 100 m above the crater rim and onto the upper SW flank. Webcam images on 20 February showed two separate fountains of incandescent material, suggesting that a second vent had opened to the E of the first vent. Spatter was ejected as high as 80 m above the crater rim and onto the upper NE flank. A sequence of Strombolian explosions were visible from 2030 on 20 February to 0630 on 21 February. Material was ejected as high as 80 m above the crater rim and onto the upper E flank.

Volcanos

Roundup of Global Volcanic Activity – New activity for the week 15 February – 21 February 2023

Aira – Kyushu (Japan) : JMA reported ongoing eruptive activity at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) during 13-20 February and crater incandescence was visible nightly. Five explosions and five eruptive events were recorded during the week. One of the explosions, at 1448 on 14 February, produced an ash plume that rose 2.4 km above the crater rim and ejected large blocks 1.1 km from the vent. Blocks 3 cm in diameter fell near the Arimura Lava Observatory in Arimura-cho, Kagoshima City, about 3 km SE. An explosion on 19 February produced an eruption plume that rose 1.2 km and ejected blocks that fell 1.1 km away. A very small eruptive event occurred at Showa Crater on 20 February.

Ambae – Vanuatu : Vanuatu Meteorology and Geo-Hazards Department (VMGD) reported that on 20 February a steam-and-ash plume rose from the active vent at Ambae and drifted SSW.

Chikurachki – Paramushir Island (Russia) : KVERT reported that moderate eruptive activity at Chikurachki had ended, with explosions and ash plumes last recorded on 8 February. Steam-and-gas emissions persisted.

Karangetang – Sangihe Islands : According to PVMBG the eruption at Karangetang’s Main Crater (S crater) continued during 14-21 February. Multiple nighttime webcam images posted with daily reports showed three main incandescent lava flows of different lengths descending the S, SW, and W flanks; a webcam image from 2156 on 17 February possibly showed incandescent material descending the SE flank. Incandescent rocks dotted the upper flanks, possibly from ejected or collapsed material from the crater; the incandescence was often most intense at the summit. Based on analyses of satellite imagery and weather models, the Darwin VAAC reported that during 16-20 February daily ash plume rose to an altitude of 2.1-3 km (7,000-10,000 ft) a.s.l. and drifted NNE, E, and SE. BNPB reported that as of 16 February there were as many as 77 people that had been displaced by the eruption and were in the East Siau Museum which was designated as a temporary evacuation shelter.

Lascar – Northern Chile : SERNAGEOMIN reported that during 15-21 February seismicity at Láscar continued to be dominated by volcano-tectonic signals with smaller numbers of both long-period and tornillo-type events. Daily whitish gas emissions were mostly diffuse, rose as high as 500 m above the crater rim, and drifted mainly E, SE, and W. Sulfur dioxide emissions were low, no notable deformation was detected, and no thermal anomalies were identified in satellite images.

Volcanos

Roundup of Global Volcanic Activity – Ongoing activity for the week 8 February – 14 February 2023

Ahyi – Mariana Islands (USA) : Unrest at Ahyi Seamount continued during 7-14 February. Pressure sensors on Wake Island, 2,270 km E of Ahyi Seamount, occasionally detected possible activity including possible explosions during 13-14 February. No activity was identified in satellite images, though the image resolutions were too low to detect water discoloration.

Cotopaxi – Ecuador : IG reported that the eruption at Cotopaxi continued during 7-14 February, characterized by daily or almost daily emissions of gas, steam, and ash; inclement weather conditions occasionally prevented views. Gas-and-ash emissions rose as high as 2 km above the crater rim and drifted NW, W, and E during 7-10 February. Minor ashfall was reported in the parish of Tambillo (32 km NNW), Mejia region, on 10 February. Steam-and-gas emissions rose to 1 km and drifted W and SW on 11 February. Gas-and-ash plumes rose around 500 m on 12 February and drifted SW. Minor amounts of ash fell in El Chasqui (17 km W), Mulaló (19 km SW), and San Juan de Pastocalle (20 km WSW). During 13-14 February several steam-and-ash emissions rose as high as 1 km and drifted W and SW. Minor ashfall was reported in Mulaló, San Agustín (11 km W), Ticatilín (15 km WSW), San Ramón (17 km SW), Control Caspi (20 km WSW), and in Pastocalle (22 km W).

Dukono – Halmahera : PVMBG reported that white-and-gray plumes of variable densities rose from Dukono as high as 150 m above the summit and drifted S and E on 8 and 10 February. Inclement weather conditions sometimes prevented visual observations.

Ebeko – Paramushir Island (Russia) : KVERT reported that moderate activity at Ebeko was ongoing during 2-9 February. According to volcanologists in Severo-Kurilsk (Paramushir Island, about 7 km E) explosions during 4-5 and 7-8 February generated ash plumes that rose as high as 4.5 km (14,800 ft) a.s.l. and drifted NE and E. Ashfall was reported in Severo-Kurilsk on 5 and 8 February. A thermal anomaly was identified in satellite images on 8 February.

Great Sitkin – Andreanof Islands (USA) : AVO reported that a 6 February satellite image confirmed continuing lava effusion at Great Sitkin and growth of the flow field to the E; effusion likely continued during 7-14 February. Weather clouds often obscured satellite and webcam views, though steam emissions were observed during 8 and 11-12 February. Seismicity was low most of the week; a network outage began at 2120 on 12 February and prevented transmission of seismic data.

Huaynaputina – Peru : IGP reported that on 4 February a small-to-medium lahar descended the El Volcán drainage, on the S flank of Huaynaputina, and traveled to within 500 m of Quinistaquillas, in the province of Sánchez Cerro, Moquegua region.

Ibu – Halmahera : PVMBG reported that the eruption at Ibu continued during 7-14 February. White-and-gray plumes of variable densities rose as high as 800 m above the summit and drifted NE and NW during 6-7 February.

Kerinci – Central Sumatra : PVMBG reported that the eruption at Kerinci was ongoing during 8-14 February. Ash plumes were visible on most days, though weather conditions prevented views towards the end of the week. At 0724 on 8 February a gray ash plum rose 150 m above the summit and drifted E. Gray-to-brown ash plumes rose 150 m and drifted NE that same day. White-and-gray ash plumes rose 150 m and drifted NE during 9-10 February. At 1740 on 10 February a dense gray ash plume rose around 100 m and drifted E, and on 14 February white-and-brown ash plumes rose 200 m and drifted NE.

Kilauea – Hawaiian Islands (USA) : HVO reported that lava continued to erupt from three locations on Kilauea’s Halema’uma’u Crater floor during 7-14 February. The lava lake in E half of the crater was active and remained at about 10 hectares in size. A small 3-6 m high lava fountain in the S part of the E lake was active during the first few days but had diminished during 10-11 February and remained at lower levels during the rest of the week. The smaller western lake in the basin of the 2021–2022 lava lake as well as the smaller lava pond in the central portion of the crater floor remained active and overflowed frequently each day. Activity in the southern small lava pond had decreased. During 12-14 February a small lava fountain was visible in the smaller central lava pond and was active along with the fountain in the S part of the E lake. Lava continued to overflow the pond and possibly connected to the larger E lava lake.

Lewotolok – Lembata Island : PVMBG reported that the eruption at Lewotolok was ongoing during 7-14 February. Minor crater incandescence at the summit was visible in most of the daily webcam images posted with the daily PVMBG reports. A webcam image captured at 2140 on 11 February showed Strombolian activity. White-and-gray plumes rose as high as 300 m above the crater rim and drifted NE, E, and SE on each day except 9-10 and 14 February due to weather clouds.

Marapi – Central Sumatra : PVMBG reported that the eruption at Marapi continued during 8-14 February. White, gray, and black plumes rose as high as 400 m and drifted SW and S on 10 February. At 1827 a dense black ash plume rose 400 m and drifted NE and E. White-and-gray plumes that were sometimes dense rose as high as 200 m and drifted E and SE on 12 February. Diffuse white-and-gray plumes rose 100 m and drifted N and S on 13 February.

Merapi – Central Java : BPPTKG reported that the eruption at Merapi continued during 3-9 February and seismicity remained at high levels. The SW lava dome produced five lava avalanches that traveled as far as 1.8 km down the SW flank (upstream in the Kali Bebeng drainage) and one pyroclastic flow traveled 1.5 km SW (on 8 February). No significant morphological changes to the central and SW lava domes were evident in webcam images.

Semeru – Eastern Java : PVMBG reported that the eruption at Semeru continued during 6-12 February. Somewhat dense to dense white-and-gray ash plumes rose 300-500 m above the summit and drifted N and NE, though weather conditions often prevented visual observations. At 0623 on 11 February a white-and-brown ash plume rose 600 m above the summit, and at 0754 a dense white-to-gray ash plume rose 600 m and drifted E. At 0527 on 14 February a somewhat-dense, white-to-gray ash plume rose around 800 m. Avalanches of material were detected during the week and sometimes roaring was heard, but they were rarely seen due to weather. Deformation fluctuated and was characterized by overall inflation. The number of earthquakes increased.

Semisopochnoi – Aleutian Islands (USA) : AVO reported that eruptive activity at Semisopochnoi’s Mount Young continued during 7-14 February. Seismicity was low, and a few local earthquakes were recorded during 7-8 February. Steam emissions were visible in webcam images almost daily though views were often cloudy.

Sheveluch – Central Kamchatka (Russia) : KVERT reported that the ongoing eruption at Sheveluch during 2-9 February was generally characterized by explosions, hot avalanches, lava-dome extrusion, and strong fumarolic activity. A daily thermal anomaly was identified in satellite images, and minor ash plumes from lava-dome collapses drifted 110 km NE on 6 February.

Suwanosejima – Ryukyu Islands (Japan) : JMA reported that the eruption at Suwanosejima’s Ontake Crater continued during 6-13 February with a total of 10 explosions recorded by the seismic network. The explosions produced eruption plumes that rose as high as 1.5 km above the crater rim and ejected large blocks as far as 400 m from the vent. Crater incandescence was observed nightly. Occasional ashfall was reported in Toshima village (3.5 km SSW).

Tangkuban Parahu – Western Java : PVMBG issued a special report based on recent observations of Tangkuban Parahu. Webcam images captured from 1830 on 9 February to 0300 on 10 February showed incandescence emanating from Ecoma Crater. A team of PVMBG scientists inspected the crater during 1900-2000 on 10 February to identify the source of the incandescence. They observed intense emissions rising from Ecoma Crater, heard roaring and rumbling, and detected a strong sulfur odor, but did not see incandescence. Remote measurements of solfatara temperatures in Ecoma Crater using thermal cameras show varying temperatures, with a maximum of 105 degrees Celsius, and were influenced by airflow conditions at the crater. A multi-gas detector did not record high concentrations of volcanic gases. Seismic data from June 2022 to February 2023 suggested variable rates of fluid movement and increased heating of the subsurface to the surface. Data from monitoring instruments and visual observations indicated that the incandescent was not caused by rising magma and instead by reactions of sulfur deposits around the vents.

Villarrica – Central Chile : The eruption at Villarrica was ongoing during 6-12 February. POVI reported that three explosions were heard during 1940-1942 on 6 February, and then hours later spatter was seen rising 30 m above the crater rim. On 9 February lava fountains were seen rising around 50 m above the crater rim. SERNAGEOMIN noted that in the early part of the week small Strombolian explosions and gas emissions were recorded and observed in webcam images. A period of increased seismicity was recorded on 12 February, after several weeks of stable levels. The seismicity and recent visual observations (especially ash emissions observed on 27 January) indicated that activity was localized at shallow levels, without a clear indication of deep magmatic contribution.

Volcanos

Roundup of Global Volcanic Activity – New activity for the week 8 February – 14 February 2023

Aira – Kyushu (Japan) : JMA reported ongoing eruptive activity at Aira Caldera’s Sakurajima volcano during 6-12 February and nightly crater incandescence. Three eruptive events and two explosions were recorded at Minamidake Crater. The first explosion, at 1815 on 9 November, generated an ash plume that rose 2 km above the crater rim and drifted N and ejected large blocks 600-900 m from the crater rim. The second explosion, at 1007 on 11 February, produced an ash plume that rose 1.7 km and ejected large blocks 600-900 m from the crater rim. An ash plume from an eruptive event at 1323 on 12 February rose 1.7 km and drifted E. A very small eruption at Showa Crater at 1052 on 8 February produced an ash plume that rose 800 m above the crater rim. This was the first eruption at Showa Crater since 3 April 2018. Ash plumes from events recorded at 1110 and 1425 rose as high as 1 km and drifted SE and SW, respectively, and blocks were ejected 200-300 m from the crater. Ashfall was reported in an area from Arimura-cho (4.5 km SE) to Furusato-cho (3 km S).

Chikurachki – Paramushir Island (Russia) : KVERT reported that a moderate explosive eruption at Chikurachki continued during 2-9 February. A thermal anomaly was identified in satellite images during 5-6 February and ash plumes drifted 125 km SE, E, and NE.

Karangetang – Sangihe Islands : According to PVMBG the eruption at Karangetang’s Main Crater (S crater) continued during 8-14 February. Multiple nighttime webcam images posted with daily reports showed three main incandescent lava flows of different lengths descending the S, SW, and W flanks. Incandescent rocks dotted the upper flanks, possibly from ejected or collapsed material from the crater; the incandescence was most intense at the summit.

Lascar – Northern Chile : SERNAGEOMIN reported that seismicity at Láscar was dominated by volcano-tectonic signals with smaller numbers of both long-period and tornillo-type events during 7-14 February. Seismicity increased during the week, associated with continuing effusion of the dome-like structure that had emerged on the crater floor on 30 January. Daily whitish gas emissions were mostly diffuse and rose around 400 m above the crater rim, though emissions rose as high as 700 m during 11-12 February. Sulfur dioxide emissions were low, no deformation was detected, and no thermal anomalies were identified in satellite images.

Tengger Caldera – Eastern Java : PVMBG sent a team of scientists to investigate Tengger Caldera’s Bromo cone after an increase in activity was detected on 3 February, characterized by crater incandescence, rumbling sounds, and a strong sulfur dioxide odor. They observed somewhat dense white emissions rising as high as 300 m during 9-12 February and heard moderate-to-strong rumbling noises. A sulfur dioxide odor was strong near the crater and measurements indicated that levels were above the healthy (non-hazardous) threshold of 5 parts per million; differential optical absorption spectroscopy (DOAS) measurements indicated an average flux of 190 tons per day on 11 February. During clear periods the largest solfatara on the NNW part of the crater floor was visible and ranged in temperature from 46 to 66 degrees Celsius based on handheld instruments. Crater incandescence, originating from the solfatara, was visible at night.

Volcanos

Roundup of Global Volcanic Activity – Ongoing activity for the week 1 February – 7 February 2023

Ahyi – Mariana Islands (USA) : Unrest at Ahyi Seamount continued during 31 January-7 February. Pressure sensors on Wake Island, 2,270 km E of Ahyi Seamount, detected activity during 31 January-1 February and possible activity during 4-6 February. Plumes of discolored water were not identified satellite images, though the image resolutions were too low to detect it.

Aira – Kyushu (Japan) : JMA reported ongoing eruptive activity at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) during 30 January-6 February and crater incandescence was visible nightly. Sulfur dioxide emissions were high at 2,000 tons per day on 30 January. An explosion at 1951 on 3 February produced an ash plume that rose 1.2 km above the crater rim and ejected large blocks as far as 500 m from the crater.

Cotopaxi – Ecuador : IG reported that the eruption at Cotopaxi continued during 1-7 February, characterized by daily emissions of gas, steam, and ash emissions; inclement weather conditions occasionally prevented views. Gas-and-steam emissions were visible rising from the crater on 1 February. Seismicity increased at 0100 on 2 February and was associated with an ash plume that rose 1.3 km above the summit and drifted NW. Later that day emissions containing ash rose as high as 2.5 km and drifted N, NE, and SE. Ashfall was reported in the N part of Parque Nacional Cotopaxi, and in the area of the Tesalia (47 km NNW) and Güitig factories. Ashfall was also reported in the Quito and Mejía regions including in Amaguaña (35 km NNW), Quitumbe (43 km NNW), Conocoto (41 km N), Guamaní, La Ecuatoriana (44 km NNW), Turubamba (43 km NNW), Chillogallo (47 km NNW), La Magdalena, Machachi (24 km NW), Tambillo (32 km NNW), Alóag (28 km NW), and Cutuglahua (35 km NNW). On 3 February ash plumes rose as high as 2.5 km and drifted in multiple directions, and ash fell in Amaguaña, La Armenia, Quitumbe, Conocoto, Guamaní, La Ecuatoriana, Turubamba, Chillogallo, La Magdalena, Machachi, Tambillo, Alóag, Cutuglahua, Uyumbicho (30 km NNW), Aloasí (24 km NW), and El Chaupi (24 km WNW). On 4 February ash plumes rose 1.5 km and drifted NNE and SE. Ashfall was noted in Guamaní, Turubamba, Chillogallo, La Ecuatoriana, Quitumbe, Tambillo, Machachi, Aloasí, Aloag, and Conocoto. On 5 February steam-and-gas emissions with low ash content drifted NW. In the afternoon ash emissions rose 200 m and drifted S. Minor gas emissions were visible during 6-7 February.

Ebeko – Paramushir Island (Russia) : KVERT reported that moderate activity at Ebeko was ongoing during 26 January-2 February. According to volcanologists in Severo-Kurilsk (Paramushir Island, about 7 km E) explosions during 28-29 and 31 January and 1 February generated ash plumes that rose as high as 4 km (13,100 ft) a.s.l. and drifted NE. A thermal anomaly was identified in satellite images on 31 January.

Etna – Sicily (Italy) : INGV reported that the vents at the NE base of Etna’s SE Crater, in the Valle del Leone at about 2,800 m elevation, continued to feed lava flows during 30 January-5 February. The flow rate was highly variable with an increase on 1 February, a gradual decrease overnight during 1-2 February, and a complete cessation on the morning of 2 February. Later, during the afternoon of 2 February, lava again effused from the vent and traveled over pre-existing flows. The effusion rate started to decrease in the afternoon of 4 February and progressively decreased overnight into 5 February. By the afternoon of 5 February, the flows appeared to be cooling. Intense gas emissions rose from Bocca Nuova Crater while gas emissions at Northeast Crater (NEC) and Voragine were minimal. Activity at Southeast Crater was characterized by fumarolic activity localized along the crater rim and from the May-June 2022 eruptive vent which also occasionally produced flashes of incandescence at night. Occasional diffuse ash emissions were also visible and rapidly dispersed with the wind.

Fuego – South-Central Guatemala : INSIVUMEH reported that 4-12 explosions per hour were recorded at Fuego during 31 January-6 February, generating ash plumes that rose as high as 1.1 km above the crater rim and drifted as far as 20 km SW, WSW, and W. Ashfall was recorded during 2-4 February in areas downwind including Morelia (9 km SW), Panimaché I and II (8 km SW), Santa Sofía (12 km SW), El Porvenir (8 km ENE), San Pedro Yepocapa (8 km NW), and Finca Palo Verde. Daily block avalanches descended various drainages including the Ceniza (SSW), Seca (W), Trinidad (S), Taniluyá (SW), Honda, Las Lajas (SE), and El Jute (ESE), and often reached vegetated areas. Daily shock waves rattled structures in communities around the volcano and rumbling was often heard. Explosions ejected incandescent material 100-200 m above the summit each day. Resuspend ash deposits from high winds during 3-4 February formed “curtains” of ash on the S flank.

Great Sitkin – Andreanof Islands (USA) : AVO reported that seismicity at Great Sitkin was low during 1-7 February. No activity was observed, though weather clouds obscured satellite and webcam views.

Kerinci – Central Sumatra : PVMBG reported that the eruption at Kerinci was ongoing during 1-7 February. An eruptive event was recorded at 0230 on 3 February but was not visually confirmed. White-and-gray ash plumes were visible later that day rising 100 m above the summit and drifting NE and E. At 0646 on 4 February a gray-to-brown ash plume rose 200 m and drifted E and SE. At 0722 on 5 February a dense brown ash plume rose 200 m and drifted NE and E. White-and-brown emissions rose as high as 150 m on 7 February.

Kilauea – Hawaiian Islands (USA) : HVO reported that lava continued to erupt on Kilauea’s Halema’uma’u Crater floor during 1-7 February. Activity was concentrated in the E half of the crater in a large, perched lava lake with well-defined levees, covering about 10 hectares. A smaller lake to the W was active in the basin of the 2021-2022 lava lake. Part of the E lake began to crust over on 1 February, forming a crusted isthmus through the center of the lake and two smaller areas of lava on the N and S sides. The lava fountain was located on the S side. Lava in each of the two smaller areas independently circulated in opposite directions from each other. At around 2315 lava fountaining ceased but resumed about 45 minutes later, rising 1-2 m. During 0100-0400 on 2 February lava from the S side flooded across the whole E lake, covering the isthmus, and returning the E lake to the size it was (10 hectares). The W Lake, and two smaller lava ponds in the central and S portions of the crater floor, remained relatively stable, though one of the ponds overflowed. Two small floating islands in the E lake sank during 2-3 February. During 2-7 February the E lake, the W lake, and the two small lava ponds remained active and stable. The lava fountain continued to be active, though during 4-5 February bursts of activity caused the fountain to double in height. A second small lava fountain was temporarily active near the first fountain during 0300-0700 on 5 February. Starting at around 2100 on 5 February through 0900 on 6 February a large breakout occurred on the N portion of the crater floor covering an area equal to or slightly larger than the E lava lake. A smaller breakout S of the E lake occurred around 0000 on 6 February. The large breakout continued to be active on 6 February but was only weakly active by 7 February.

Lewotolok – Lembata Island : PVMBG reported that the eruption at Lewotolok was ongoing during 1-7 February. Incandescence above the crater was visible in a 1 February webcam image. White-and-gray plumes rose as high as 400 m above the crater rim and drifted E and SE on 1 and 5 February. White plumes of variable densities were visible on other days of the week.

Marapi – Central Sumatra : PVMBG reported that the eruption at Marapi continued during 1-7 February. White-and-gray emissions rose as high as 200 m and drifted in various directions during 1-2 and 4 February; white steam plumes were visible on 3 February. White-and-brown plumes rose as high as 400 m on 6 February. Weather clouds sometimes prevented views of the volcano.

Merapi – Central Java : BPPTKG reported that the eruption at Merapi continued during 27 January-2 February and seismicity remained at high levels. The SW lava dome produced six lava avalanches that traveled as far as 1.8 km down the SW flank (upstream in the Kali Bebeng drainage); occasional avalanche sounds were recorded. No significant morphological changes to the central and SW lava domes were evident in webcam images. At 0710 on 8 February a pyroclastic flow traveled 1.5 km down the Boyong drainage on the SW flank. Ashfall was reported in areas downwind including Sangup, Musuk, and Mriyan.

Santa Maria – Southwestern Guatemala : INSIVUMEH reported that the eruption at Santa María’s Santiaguito lava-dome complex continued during 31 January-6 February. Effusion from Caliente cone fed lava flows that descended the San Isidro and Zanjón Seco drainages on the W and SW flanks; the longest part of the lava flow was 4.4 km on 15 January. Incandescence from the dome and the lava flows was visible nightly. Block-and-ash flows from the dome, and from both the ends and sides of the flows, descended the S, SW, and W flanks almost daily. “Curtains” of ash sometimes rose several hundred meters along their paths. Explosions were generally weak-to-moderate in size and produced gas-and-steam plumes with minor amounts of ash that rose several hundred meters above the complex. Explosions and accompanying rumbling were heard in El Palmar (12 km SSW) during 3-4 February. Ashfall from both explosions and block-and-ash flows was reported in the Monte Claro (S), El Faro, and La Florida (6 km S), Santa Marta, and El Viejo Palmar (11 km S) ranches during 3-4 February.

Semeru – Eastern Java : PVMBG reported that the eruption at Semeru continued during 1-7 February. White-and-gray ash plumes that were somewhat dense rose 300-700 m above the summit and drifted N, NE, S, and SW. One of the ash plumes, recorded at 0729 on 1 February, was a dense white-and-gray plume that rose 700 m and drifted NE. At 0700 on 2 February an ash plume rose 600 m and drifted NE. On 3 February white-and-gray plumes rose 100-300 m and drifted S, SW, W, and N. An eruptive event at 1242 on 5 February produced a white, gray, and brown ash plume that rose around 1.5 km and drifted N. Webcam images showed a pyroclastic flow descending the SE flank and ash plumes rising its path. 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, and 500 m from Kobokan drainages within 17 km of the summit, along with other drainages originating on Semeru, including the Bang, Kembar, and Sat, due to lahar, avalanche, and pyroclastic flow hazards.

Semisopochnoi – Aleutian Islands (USA) : AVO reported that eruptive activity at Semisopochnoi’s Mount Young continued during 1-7 February. Seismicity was elevated and daily weak tremor was recorded. Minor steam emissions were visible in webcam images during 3-7 February.

Sheveluch – Central Kamchatka (Russia) : KVERT reported that the ongoing eruption at Sheveluch during 26 January-2 February was generally characterized by explosions, hot avalanches, lava-dome extrusion, and strong fumarolic activity. A persistent thermal anomaly was identified daily in satellite images, and minor ash plumes from explosions and lava-dome collapses drifted 70 km NE on 27 and 31 January and 2 February.

Suwanosejima

Ryukyu Islands (Japan)

JMA reported that the eruption at Suwanosejima’s Ontake Crater continued during 30 January-6 February with a total of seven explosions recorded by the seismic network. The explosions produced eruption plumes that rose as high as 1.5 km above the crater rim and ejected large blocks as far as 400 m from the vent. Crater incandescence was observed nightly. Occasional ashfall and rumbling noises were reported in Toshima village (3.5 km SSW).