Windowed ETAS models with application to the Chilean seismic catalogs

The seismicity in Chile is estimated using an ETAS (Epidemic Type Aftershock sequences) space-time point process through a semi-parametric technique to account for the estimation of parametric and nonparametric components simultaneously. The two components account for triggered and background seismicity respectively, and are estimated by alternating a ML estimation for the parametric part and a forward predictive likelihood technique for the nonparametric one. Given the geographic and seismological characteristics of Chile, the sensitivity of the technique with respect to different geographical areas is examined in overlapping successive windows with varying latitude. A different behavior of background and triggered seismicity in the different windows is observed and analyzed.