Roundup of Global Volcanic Activity - New Activity for the week 26 October - 1 November 2022
Bezymianny - Central Kamchatka (Russia) : KVERT reported that notable activity continued after the strong explosive 23-24 October phase at Bezymianny through 27 October. Intense fumarolic activity was visible, the lava dome was incandescent at night, and collapses from the dome produced avalanches of hot material. Ash plumes from the collapses were sometimes large; on 26 October an ash cloud 10x13 km in dimension drifted 70 km E on 26 October.
Cotopaxi - Ecuador : IG issued a report that included data analysis and additional information about the minor eruptive activity at Cotopaxi recorded during 21-22 October. The eruption began with a high-frequency earthquake recorded at 1944 on 21 October and was followed by an episode of volcanic tremor from 1950 on 21 October to 0040 on 22 October. A diffuse gas-and-ash cloud rose 1.7-2.3 km above the summit and drifted NE. Ashfall was reported in the José Rivas Refuge for climbers on the N flank. Parque Nacional Cotopaxi closed to visitors due to the emissions. A small thermal anomaly in the summit crater was identified in satellite images on 23 October; a small anomaly had been repeatedly visible since the previous eruption during August-November 2015, though it had been absent since 12 November 2020. On 22 October scientists measured sulfur dioxide emissions using a mobile Differential Optical Absorption Spectroscopy (DOAS) instrument in an area spanning near the W entrance to Parque Nacional Cotopaxi to areas in the park. They measured higher values, 1,580 tons per day, nearer to the volcano. Analysis of ash samples collected by IG scientists at the José Rivas Refuge revealed that about 22 percent was juvenile material, indicating a magmatic component to the eruption. Parque Nacional Cotopaxi reopened on 26 October. Seismicity was at moderate levels that same day with the number of events per day progressively decreasing according to a news report. During an overflight of the summit crater on 27 October, scientists observed gas-and-steam emissions rising 500 m above the carter rim, obscuring views into the crater. The amplitude of the tremor signal on 21 October was about half of that recorded during the 2015 eruption and the tremor signal only lasted about four hours whereas in 2015 some periods lasted several days. There was no notable precursory activity including anomalous seismic activity and deformation detected in satellite or GPS data. The Washington VAAC had previously reported ash emissions on 4 July 2016, 23 January 2017, 15 July 2018, and 10 January 2020, though none were associated with increased seismicity or ashfall. Climbers had previously reported ashfall on occasion, with the last report on 27 November 2021. Servicio Nacional de Gestión de Riesgos y Emergencias (SNGRE) maintained the Alert Level at Yellow (the second lowest level on a four-color scale).
Kerinci - Central Sumatra : PVMBG reported that on 27 October a somewhat dense, gray-and-black plume rose around 300 m above Kerinci’s summit and drifted E.
Manam - Northeast of New Guinea : The Darwin VAAC reported that on 29 October an ash plume from Manam rose to 1.5 km (5,000 ft) and drifted NW based on satellite images. The plume had dissipated within three hours.
Taal - Luzon (Philippines) : PHIVOLCS reported continuing unrest at Taal during 25-31 October. Sulfur dioxide emissions averaged 544 tonnes per day on 27 October. There were 2-16 daily counts of small phreatomagmatic bursts during 25-29 October. The Tokyo VAAC noted that three ash plumes rose as high as 600 m (2,000 ft) a.s.l. and drifted NW and SW during 26-28 October based on SIGMETS (Significant Meteorological statements) issued by the Ninoy Aquino International Airport. Six volcanic earthquakes and a three-minute-long tremor signal were recorded during 25-26 October, four periods of volcanic tremor were recorded during 28-29 October, and 64 periods were recorded during 31 October-1 November. Upwelling gasses and hot fluids in the lake were visible early in the week; white steam emissions rose as high as 600 m above the lake on most of the days.
Villarrica - Central Chile : POVI reported that Strombolian explosions at Villarrica intensified on 31 October and ejected material onto the upper flanks. A lava fountain rising above the crater rim was visible on 1 November.
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