Volcanos

Roundup of Global Volcanic Activity - Ongoing Activity for the week 26 October - 1 November 2022

Aira - Kyushu (Japan) : JMA reported ongoing eruptive activity at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) and nighttime crater incandescence. Two eruptive events and one explosion were recorded during 24-28 October. Volcanic plumes rose as high as 1.2 km above the crater rim and large blocks were ejected as far as 1.3 km from the vent. Very small eruptive events were occasionally recorded during 28-31 October.

Alaid - Kuril Islands (Russia) : KVERT reported that the eruption at Alaid was ongoing during 20-27 October. An intense daily thermal anomaly was identified in satellite images. Ash plumes drifted more than 700 m NE and SE.

Bagana - Bougainville (Papua New Guinea) : The Darwin VAAC reported that during 31 October-1 November ash plumes from Bagana rose to 2.1-2.7 km (7,000-9,000 ft) a.s.l. and drifted NE, N, and WSW based on satellite data. An intense thermal anomaly was present at the summit.

Ebeko - Paramushir Island (Russia) : KVERT reported that moderate activity at Ebeko was ongoing. According to volcanologists in Severo-Kurilsk (Paramushir Island, about 7 km E) explosions during 22 and 25-27 October generated ash plumes that rose to 2.5 km (8,200 ft) a.s.l. and drifted NE. A thermal anomaly was identified in satellite images on 26 October.

Great Sitkin - Andreanof Islands (USA) : AVO reported that seismicity at Great Sitkin was very low during 25 October-1 November and nothing significant was seen in partly cloudy satellite or web camera views. Lava effusion likely continued.

Kilauea - Hawaiian Islands (USA) : HVO reported that lava continued to effuse from a vent in the lower W wall of Kilauea’s Halema`uma`u Crater during 25 October-1 November entering the lava lake and flowing onto the crater floor. The active part of the lake remained at a steady level all week.

Krakatau - Sunda Strait : PVMBG reported that multiple ash plumes were visible in webcam images rising from Anak Krakatau during 26-28 October. Dense gray ash plumes rose as high as 300 m above the summit and drifted NE at 0949 on 26 October, 1205 on 27 October, and 0438 and 1502 on 28 October. Eruptive events were also recorded at 1838 on 26 October, 1955 on 27 October, and 0438 on 28 October, though were not visually confirmed.

Maly Semyachik - Eastern Kamchatka (Russia) : Although Maly Semyachik was not erupting, KVERT raised the Aviation Color Code to Orange (the second highest level on a four-color scale) on 28 October, noting that a plume of ash, re-suspended by strong winds, was visible in satellite images drifting 123 km SE. Within three hours.

Mauna Loa - Hawaiian Islands (USA) : HVO reported continuing unrest at Mauna Loa during 25 October-1 November. The seismic network detected 19-41 daily small-magnitude (below M 3) earthquakes 3-5 km beneath Mokua’weoweo caldera and 1-8 km beneath the upper NW flank of Mauna Loa. Data from Global Positioning System (GPS) instruments at the summit and flanks showed continuing inflation, though data from tiltmeters at the summit did not show significant surface deformation over the past week.

Mayon - Luzon (Philippines) : On 28 October PHIVOLCS warned of potential lahars around Mayon due to intense rains from an impending tropical storm. The rains could generate lahars in several drainages, including in the Miisi, Binaan, Anoling, Quirangay, Maninila, Masarawag, Muladbucad, Nasisi, Mabinit, Matan-ag, and Basud. Communities along the middle and lower flanks and in areas downstream were vulnerable to lahars.

Merapi - Central Java : BPPTKG reported that the eruption at Merapi continued during 21-27 October and seismicity remained at high levels. The SW lava dome produced as many as 14 minor lava avalanches that traveled as far as 1.5 km down the Bebeng drainage on the SW flank. No significant morphological changes to the central and SW lava domes were evident in drone photographs.

Nevado del Ruiz - Colombia : On 1 November Servicio Geológico Colombiano’s (SGC) reported that during the previous week seismicity at Nevado del Ruiz was variable and indicated continuing growth of the lava dome in Arenas Crater. The number and size of seismic signals indicating fluid movement had decreased compared to the week before. Some of the signals were associated with gas-and-ash emissions. Although seismic signals indicating rock fracturing decreased in number, magnitudes were higher previous week. The hypocenters were located 0.2-7 km deep, mainly beneath the NE and SW parts of Arenas Crater, and beneath the E, SE, and NW flanks. The largest event was a local M 1.8 that was recorded at 0518 on 28 October at a depth of 1.8 km below the crater. Several low-to-moderate thermal anomalies in Arenas Crater were identified in satellite images and minor changes to the dome and crater floor were visible. Plumes of steam and gas (mainly sulfur dioxide) continued to be emitted, rising as high as 1.8 km above the summit on 31 October and drifting SE, ESE, and ENE.

Pavlof - Alaska Peninsula, Alaska : AVO reported that a minor eruption at a vent on Pavlof’s upper E flank was ongoing during 26 October-1 November and nearly continuous seismic tremor was recorded. Multiple explosions, detected almost daily in seismic and infrasound data, had intensified during the previous week. No significant activity was observed in cloudy-to-partly-cloudy satellite and webcam views during most of the week; diffuse steam-and-ash plume rose less than 3 km (10,000 ft) a.s.l. during 31 October-1 November and deposited minor amounts of tephra on the E flank.

Sheveluch - Central Kamchatka (Russia) : KVERT reported that the ongoing eruption at Sheveluch during 20-27 October was generally characterized by explosions, hot avalanches, and lava-dome extrusion. A daily thermal anomaly was identified in satellite images. Collapses generated hot avalanches and ash plumes that drifted 80 km SE and NW during 24-25 October.

Suwanosejima - Ryukyu Islands (Japan) : JMA reported that the eruption at Suwanosejima's Ontake Crater continued during 24-31 October and crater incandescence was visible nightly. A total of six explosions produced eruption plumes that rose as high as 2.1 km above the crater rim and ejected blocks as far as 300 m from the vent. Occasional rumbling noises and ashfall were reported in Toshima village (3.5 km SSW). The number of volcanic earthquakes increased starting at 0600 on 31 October; a total of about 355 events, located beneath the W flank, were recorded by 1500.

Yasur - Vanuatu : On 27 October 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). Ash-and-gas emissions and low-to-moderate explosions continued to be recorded, with bombs falling in and around the crater.