Seismic swarm at Chile’s Copahue volcano increases likelihood of new eruptions

January 23, 2013 – CHILE – Seismic activity increased significantly during 22 Jan, SERNAGEEOMIN reported in two special bulletins. No eruptive activity at the surface has occurred so far, and the official alert level of the volcano remains at “Yellow,” but with “Special Attention.” Until 09:56 local time (12:56 GMT) on 22 Jan, seismic activity had remained at low levels, both in occurrence of earthquakes, the energy released and the signal intensity of tremor associated with fluid movements inside the volcano. Then, at that time, there was a significant long-period (LP) earthquake and 3 hours later, shallow lower amplitude events started to occur.  At 13:20 local time, another LP earthquake of relatively strong intensity occurred and was followed by a seismic swarm with mostly long period events that continued for 20 minutes. No surface changes, no glow, and no thermal hot spot on MODIS data accompany this process for the time being, but there is an elevated possibility of new eruptions, expected to be of small phreatic size and similar to the ones in the past months. Monitoring of the volcano will be increased, Sernageomin announced. –Volcano Discovery