SEISMICITY ACTIVATED IN ANDEAN TROUGH BY STATIC STRESS INCREASE FROM THE MW=8.8, FEBRUARY 27, 2010, MAULE EARTHQUAKE

SILVANA SPAGNOTTO; TRIEP, ENRIQUE

Lima

Congreso; XVI Congreso Peruano de Geología and SEG 2012 Conference; 2012

Sociedad Geológica del Perú y Society of economic Geologist

Seismicity increase of about eight times is observed in a narrow area, oriented NNW-SSE between 35°S and 36°S and close to the Andes axis, comparing periods of 80 days before and after the great Maule earthquake. Although earthquake localizations are obtained using only two seismic stations, we are able to acceptably define the activated area assuming an average value depth. The area coincides with the northern part of a line of Pleistocene Calderas within Las Loicas trough. Magnitude Mc varies from 0.7 to 2.5, except for two earthquakes of M=4.1 and M=4.4.