Volcanos

Roundup of Global Volcanic Activity - New Activity for the week 16 November - 22 November 2022

Ahyi - Mariana Islands (USA) : On 18 November the USGS reported that hydroacoustic and seismic signals suggestive of underwater eruptive activity at Ahyi Seamount had declined over the past week. No other signs of volcanic unrest were detected at the seamount.

Bezymianny - Central Kamchatka (Russia) : KVERT reported that during 11-17 November a daily thermal anomaly over Bezymianny was identified in satellite images. Gas-and-steam emissions were visible and occasional collapses from the growing lava dome produced avalanches of hot material.

Copahue - Central Chile-Argentina : Based on information from Observatorio Argentino de Vigilancia Volcánica (OAVV), SERNAGEOMIN and SEGEMAR reported a minor increase of activity at Copahue. RSAM values based on volcanic tremor began to increase on 13 November. Weather conditions prevented views of the volcano during 13-14 November. On 15 November an increase in the magnitudes of tremor signals was accompanied by increased and denser gas emissions rising 200 m above El Agrio Crater. The emissions, seen in webcam images, were mostly whitish and contained particulate material.

Klyuchevskoy - Central Kamchatka (Russia) : KVERT reported that a thermal anomaly over Klyuchevskoy was first identified on 13 November and was visible daily through 20 November. An explosive Strombolian eruption began at 2330 local time on 17 November, the same day that the thermal anomaly intensified. Gas-and-steam plumes drifted SE. The Strombolian eruption and gas emissions persisted.

San Miguel - Eastern El Salvador : MARN reported that an eruption at San Miguel’s central crater began on 15 November, and by 1100 on 20 November a total of 62 phreatic explosions had been recorded, averaging 10 per day. An additional 24 explosions were recorded from 1100 on 20 November to 1100 on 21 November and 12 more were recorded between 1100 and 1100 during 21-22 November. Explosions generated gas, ash, and steam plumes that generally rose around 500 m above the crater rim, though at 1336 on 18 November and 1206 on 19 November eruption plumes rose as high as 1.1 km. Some of the events were accompanied by crater incandescence during 15-20 November. Sulfur dioxide emissions generally averaged 100-170 tons per day, below the baseline of 300 tons per day. Specific measurements during explosive events revealed that the emissions were sometimes higher; 1,200 tons per day was measured on 19 November during one of the largest explosions, and 378 tons per days was measured during an explosion on 21 November. Seismicity was characterized by volcano-tectonic events, long-period events, and tremor. Deformation data showed no significant changes.

Takawangha - Andreanof Islands (USA) : The number of small earthquakes detected near the volcano had increased during from 16 November and intensified during 17-18 November. The earthquakes were located at depths of 3-6 km below sea level with the largest magnitudes between 2 and 3. The seismicity possibly indicated magma movement at depth. The intensity of the seismicity was variable during 19-22 November.

Villarrica - Central Chile : During an overflight of Villarrica on 19 November, SERNAGEOMIN scientists observed a cone on the crater floor with an incandescent vent at its center, containing a lava lake. Deposits of ejected material were seen on the flanks. That same day a 75-minute-long series of volcano-tectonic earthquakes began at 1940. There was a total of 21 events located 7.8 km ESE of the crater. The largest event, a M 1.6, occurred at 2007 at a depth of 2.5 km based on data collection and analysis of Red Nacional de Vigilancia Volcánica (RNVV) and Observatorio Volcanológico de los Andes del Sur (OVDAS), respectively.