GNGTS 2013 - Atti del 32° Convegno Nazionale

The aim of this work is to quantitatively describe the high-frequency ground motion scaling in the Chile region for constraining the amplitude expected from future earthquakes in subduction zone. To accomplish this, regressions are performed with large data sets that cover a wide range of earthquake size and hypocentral distance to calibrate model-based predictions of excitation and propagation. Data processing. We will use the same methodology (for more details see the papers below) for data processing and analysis as was successfully used in studies with data sets from Italy (Malagnini et al. , 2000a, 2002; Morasca et al. , 2006; Scognamiglio et al. , 2005), Central Europe (Malagnini et al. , 2000b; Bay et al. , 2003) and from Utah e Yellowstone (Jeon et al. , 2004). In order to obtain the scaling relationships for the high-frequency ground motion in the Maule region (Chile), regressions are carried out from 172 regional aftershocks with magnitude ranging from M w 3.7 to M w = 6.2. The digital data are corrected for instrument response to ground and the peak ground velocities are measured in selected narrow-frequency bands, between 0.2 and 30 Hz. Fig. 1 – Map of the Maule region (Chile). Beach balls indicate the moment tensor solutions of all 172 aftershock in the range M w 3.7 to 6.2. Red triangles indicate the positions of the broadband seismic stations used in this study. 89 GNGTS 2013 S essione 1.1