Application of a multi-array back-projection technique in local and regional distances in different tectonic regimes

Abstract:

In order to timely assess potential damages and manage post seismic operations, it is crucial to characterize the rupture area of large earthquakes. For this purpose, the determination of the location of strong seismic radiation, using a multi-array back-projection approach (Xie and Meng,2019), allows to predict the ground motion straightforwardly, without the know the prior knowledge of the dimensions of the fault plane and its position with respect to the hypocentre. The radiators found by merging source back-azimuth from single arrays analysis , well identify the main rupture direction. The distribution of the seismic radiators reflects the areas of large final slip. For this reason, it is possible to use the distance from seismic radiators to stations instead of the truncated Joyner-Boore distance to improve predictions of the Ground Motion Predicted Equations (Feng and Meng, 2018). In this presentation, we analyse the performance of the multi-array back-projection approach on three well studied earthquakes in different geological setting and with their magnitudes between Mw 6.5 and 8.3. We performed the back-projection considering stations located at local and regional distances, obtaining good and promising results in comparison with the previous studies. These results, that can be also obtained as preliminary and precious estimations before than more elaborate and time-consuming studies are performed, demonstrate the potential to incorporate this approach in the next-generation Earthquake Early Warning system.