[S13-3] Earthquake source mechanics III

[S13-3-05] Seismic energy release at the seismogenic zone of Guerrero, Mexico

^○Raymundo Plata-Martinez, Xyoli Perez-Campos, Shri Krishna Singh (Institute of Geophysics, UNAM, Mexico.)

To study the mechanisms that control seismic energy release along the Guerrero, Mexico, subduction zone, we estimated radiated seismic energy, stress drop and radiation efficiency of two recent large earthquakes and their aftershocks. The first earthquake occurred at the border of the states of Guerrero and Oaxaca in Ometepec on March 2012 (Mw7.5), the second earthquakes occurred 300 km away, in Papanoa on April 2014 (Mw7.2). Estimations of radiated energy scaled with seismic moment (Es/M0), show no evidence of dependence of radiated seismic energy with distance from the trench, depth, or size of earthquakes. However, scaled energy distribution behaves in a heterogeneous way parallel to the trench, and it might be influenced by lateral heterogeneities along the subduction interface. Stress drop and efficiency also reveals rough changes parallel to the trench, in a similar way as scaled energy. However, results show that Ometepec earthquakes had lower stress drops and higher radiation efficiency values compared with Papanoa sequence.