Volcanos

Roundup of Global Volcanic Activity – Ongoing Activity for the week 5 January – 11 January 2022

Aira – Kyushu (Japan) : JMA reported that incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible at night during 3-10 January. An eruptive event at 0143 on 7 January produced an ash plume that rose 1.3 km and ejected bombs 600-900 m away from the crater.

Great Sitkin – Andreanof Islands (USA) : AVO reported that slow lava effusion at Great Sitkin probably continued during 5-11 January, though cloudy conditions prevented satellite and webcam confirmation. Seismicity was very low; several small seismic events were recorded during 9-10 January.

Grimsvotn – Iceland : The Icelandic Meteorological Office (IMO) lowered the Aviation Color Code for Grímsvötn to Green on 12 January, noting that seismicity had returned to normal levels with a few earthquakes detected over the previous few weeks. The caldera had deepened during the jökulhlaup (glacial outburst flood) that had occurred during November and December 2021, though IMO noted that it was difficult to characterize the current status of the caldera and the level of the geothermal activity.

Karymsky – Eastern Kamchatka (Russia) : KVERT reported that a thermal anomaly over Karymsky was visible in satellite images during 2-3 January.

Kilauea – Hawaiian Islands (USA) : HVO reported that lava effusion resumed at the vent in the lower W wall of Kilauea’s Halema`uma`u Crater at around 0400 on 5 January, ending a 3-day pause. The sulfur dioxide emission rate was about 3,300 tonnes per day on 6 January. Lava effused from the vent on most days during 6-11 January, though effusion paused and the lake crusted over for most of the day on 7 January. Several overflows onto older crust were observed after effusion resumed at around 2130 on 7 January through 8 January. The W surface of the lava lake was active during 9-10 January, though there were some more pauses in lava effusion from the W vent during 10-11 January.

Lewotolok – Lembata Island (Indonesia) : PVMBG reported that the eruption at Lewotolok continued during 5-10 January. Variable density white-and-gray ash plumes rose as high as 600 m above the summit and drifted E and SE. Incandescent material was occasionally ejected up to 300 m from the vent and accompanied by rumbling. At 0848 on 11 January an ash plume rose 700 m above the volcano and drifted E.

Merapi – Central Java (Indonesia) : BPPTKG reported no notable morphological changes to Merapi’s summit lava dome, though the dome just below the SW rim had increased about 2 m in height during 31 December 2021 to 6 January 2022. The estimated dome volumes were over 1.67 million cubic meters for the SW dome and just over 3 million cubic meters for the summit dome. The intensity of the seismic signals remained at high levels. As many as 69 lava avalanches traveled a maximum of 2 km SW down the Bebeng drainage.

Pavlof – United States : AVO reported that elevated seismicity at Pavlof during 5-11 January was characterized by daily periods of tremor. High surface temperatures consistent with active lava effusion near the vent were identified in satellite images each day. The lava flow on the SE flank lengthened from 80 to 300 m during 2-6 January based on high-resolution satellite data. Robust steaming was observed by pilots and in webcam images on 9 January.

Rincon de la Vieja – Costa Rica : OVSICORI-UNA reported that multiple eruptive events were recorded at Rincón de la Vieja on 5 January, though most of them were small. A notable explosion at 1833 ejected incandescent material above the crater rim that was visible in webcam images for about 30 seconds. Darkness obscured views of a plume and no ash was visible in satellite images. Residents reported hearing a loud explosion and sounds indicating active lahars; lahars in the Penjamo and Azufrado rivers reached residential areas within 50 minutes of the event. An eruptive event was recorded at 1858 on 10 January, though cloud cover prevented visual confirmation.

Sangay – Ecuador : IG staff observed Sangay during an overflight on 27 December 2021, focusing on the summit area along with the SE and NE flanks. Two vents were active in the summit area, a central vent and a western vent in a scoria cone. The central vent produced Strombolian explosions and had temperatures as high as 645 degrees Celsius. Lava from this vent fed a flow on the SE flank that was 540 m long; the maximum temperature of the flow was 580 degrees. The W vent ejected blocks and gas emissions, and had temperatures as high as 410 degrees. The third vent, on the NE flank, produced gas emissions and temperatures above 515 degrees. A lava flow from this vent had descended 370 m and was as hot as 450 degrees. The team took gas measurements around the summit with a MultiGAS instrument, collected ash samples, and acquired data and conducted maintenance at the SAGA monitoring station, 6 km SW of the summit.

Semisopochnoi – Aleutian Islands (USA) : AVO reported that low-level eruptive activity and elevated seismicity at Semisopochnoi’s North Cerberus crater continued during 4-11 January. Almost daily explosions (one per day during 4-8 January and a few during 10-11 January) were recorded by the local seismic network. The weather was mostly cloudy, though ash and/or steam plumes were occasionally visible in webcam images. Low-level ash clouds were visible in webcam images during 10-11 January.

Sheveluch – Central Kamchatka (Russia) : KVERT reported that a thermal anomaly over Sheveluch was identified in satellite images during 1-7 January. Intense steam-and-gas emissions with ash were visible during 3 and 5-6 January; plumes rose as high as 4 km (13,100 ft) a.s.l. and drifted 180 km N and W.

Suwanosejima – Ryukyu Islands (Japan) : JMA reported that incandescence at Suwanosejima’s Ontake Crater was visible nightly during 3-10 January and 368 explosions were recorded. The explosions produced ash plumes that rose as high as 2 km above the crater rim and ejected material up to 1.1 km away from the crater. Eruption sounds were heard in Toshima village (4 km SSW) and ash fell there during 7-10 January.

Yasur – Vanuatu : 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. Ash-and-gas emissions were visible in webcam images at 0845, 0900, 0915 on 7 January rising above the crater rim and drifting NW.

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