2012 Copahue volcano eruption (Argentina)

CASELLI, A.T.; AGUSTO M. R.; VELEZ M.L.

Kagoshima

Congreso; IAVCEI 2013 Scientific Assembly -; 2013

IAVCEI

Copahue volcano (37,8°S, 71,2°W, 2997 masl) is one of the major examples of active volcanism in Argentina. This basaltic-andesitic stratovolcano is located on the western edge of the Caviahue caldera in the Andes. The volcano summit has nine craters aligned in the N60 °E direction, the eastern crater is the active one and it currently hosts an acidic crater lake (pH 1) with a diameter close to 250 m and 40 m depth. During the last 250 years this volcano has experienced at least 12 low intensity phreatic and phreatomagmatic eruptions. The last eruptive cycles took place from the active crater, during 1992 and 1995 characterized by phreatic eruptions and from July to October 2000 with a phreatomagmatic eruptive type, all of them with VEI 1-2. After the 02-27-2010 Maule earthquake (Chile, Mw 8.8), several variations were observed related to the local seismicity, primarily associated with an increase in the amount and type of signals Later, on 12-01-2011 a seismic swarm was registered and gaseous emissions from the crater lake started to increase in both temperature (62 °) and acidity (pH