Volcanos

Roundup of Global Volcanic Activity – New Activity for the week 26 January – 1 February 2022

Ambae – Vanuatu : On 27 January the Vanuatu Meteorology and Geo-Hazards Department (VMGD) reported that the cone in Ambae’s Lake Voui continued to grow and produce steam-and-ash emissions. Minor ashfall was reported in areas downwind, including in local villages.

Ambrym – Vanuatu : On 27 January the Vanuatu Meteorology and Geo-Hazards Department (VMGD) reported that steam-and-gas emissions rose from Ambrym’s Benbow Crater, and incandescence from the same crater was visible at night.

Batu Tara – Komba Island : Based on analyses of satellite imagery, the Darwin VAAC reported that on 31 January an ash plume from Batu Tara rose to an altitude of 1.5 km (5,000 ft) a.s.l. and drifted ESE.

Callaqui – Central Chile : In a special statement issued on 27 January, SERNAGEOMIN reported that a small area of incandescence on the SW part of Callaqui’s summit crater was visible in webcam images overnight beginning at 2155 on 26 January. The glow was persistent and visible during dark hours, and was likely the result of increased temperatures at fumarolic vents. More intense gas emissions from the same area were visible rising 380 m the next day. The report noted that this was the first time incandescence had been recorded since the camera was installed in 2012.

Chikurachki – Paramushir Island (Russia) : KVERT reported that strong gas-and-steam emissions from Chikurachki were first visible at 1200 on 31 January and likely contained ash. The plume had drifted 80 km SW at altitudes of 4.5-5 km (14,800-16,400) a.s.l. by 1418. Activity continued through the next day; a satellite image acquired at 0319 on 1 February showed ash plumes rising as high as 3 km (10,000 ft) a.s.l. and drifting 104 km WSW.

Lascar – Northern Chile : SERNAGEOMIN reported minor increases in surficial activity at Láscar. Nighttime incandescence from the crater began to be visible at least since 11 January. A total of 14 thermal anomalies were identified in satellite data during 13-28 January; the intensity of the anomalies increased on 17 January and peaked on 22 January. Emissions of gas and steam were more frequent and robust as compared to previous months, with the highest plume rising over 1 km above the crater rim on 22 January. Sulfur dioxide emissions were identified in satellite data on 8 and 17 January; instruments at EMU station, 6 km ESE, recorded increased emission rates during 17-19 January with a peak average of 1,787 tons per day on 18 January. Seismicity was at normal levels overall during 12-28 January. Low numbers and magnitudes of volcano-tectonic (VT) and long-period (LP) earthquakes were recorded by the seismic network, though 27 VT events that were low magnitude (M 1 or below) were recorded on 22 January. Satellite images acquired on 26 January showed no recent morphological changes at the crater nor deposits around the crater area.

Soufriere Hills – Montserrat : MVO issued a statement about Soufrière Hills on 28 January explaining overall trends observed in monitoring data since lava extrusion ended in 2010. They noted that although activity at the volcano had been low when analyzed on a week-to-week basis, subtle trends have emerged in the data in recent months that indicate an overall but small increase in unrest. The number of volcano-tectonic earthquakes were low, averaging one per day since the last eruption ended, though during 2018-2021 the average increased from 0.4 to 1.2 per day. Fumarolic temperatures which initially showed a cooling trend during 2013-2017 began to rise in 2018. The increase was most notable at one specific fumarole that had a temperature increase from 200 to 500 degrees Celsius; the high temperature was similar to those last recorded in 2013. Sulfur dioxide gas flux during 2020-2021 averaged 100-200 tonnes per day higher than the fluxes recorded 2018-2019, though remained below 2012-2013 levels. Slow inflation of the whole island had continued since 2010, with no changes to the patterns of deformation; changes associated with volcano-tectonic swarms were only observed in areas close to the dome. An increase in rockfall activity was also noted.

Taal – Luzon (Philippines) : PHIVOLCS reported that unrest at Taal continued during 25-31 January, and low-level background tremor persisted. One volcanic earthquake was recorded during 25-28 January. Hot volcanic fluids were upwelling in the crater lake, and daily gas-and-steam plumes rose 1.5-2 km above the lake that drifted SW and NW. Sulfur dioxide emissions continued to be elevated, averaging 10,506-18,705 tonnes/day. A series of nine phreatomagmatic bursts from the lake occurred between 1550 on 29 January and 0449 on 30 January. Each event was short-lived, only lasting between 10 seconds and two minutes, and recorded as trace signals in the seismic data but as distinct signals in the infrasound data. Each burst produced a steam-rich plume rising 400-900 m. Sulfur dioxide emissions averaged 4,829 tonnes per day on 30 January. Seismic data during 29-30 January consisted of 31 volcanic earthquakes and 14 tremor events with durations of 1-3 minutes, and during 30-31 January 13 volcanic earthquakes were recorded along with one tremor signal that lasted three minutes. Emissions rose as high as 1 km and drifted SW.

Three Sisters – Oregon : A special statement was issued by USGS on 31 January noting an increased rate of uplift at Three Sisters during the previous few years. An area 20 km in diameter, centered 5 km W of South Sister, inflated up to 2.2 cm between June 2020 and August 2021, based on analysis of satellite data. GPS data indicated that the uplift had continued to the present. Additionally, bursts of small earthquakes were recorded in October 2021, December 2021, and January 2022, all located within the area of deformation. Uplift in that area was first detected in the mid-1990s; the rate was highest during 1999-2000 at 5 km per year, but then slowed until 2020. A total of 30 cm of uplift was recorded from 1995 to 2020. The cause of the deformation was uncertain, though it was likely occurring due to small accumulations of magma at about 7 km depth based on conclusions from a 1990 study.

Wolf – Isla Isabela (Galapagos) : IG reported that the eruption at Wolf continued during 26 January-1 February. Daily thermal alert counts, anywhere from a few to well over one hundred, indicated advancing lava flows on the SE flank.

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