Ground motion variability in Israel from 3-D simulations of M 6 and M 7 earthquakes

Abstract

In Israel, due to low seismicity rates and a sparse seismic network, the temporal and spatial coverage of ground motion data is insufficient to estimate the variability in moderate-strong (M>6) ground motions required to construct a local ground motion model (GMM). To fill this data gap and to study the ground motion variability in M>6 events, we performed a series of 3-D numerical simulations of M 6 and M 7 earthquakes. Based on the results of the simulations, we developed a parametric attenuation model (AM) and studied the residuals between simulated and AM peak ground velocities (PGVs) and the single station variability. We also compared the simulated ground motions with a global GMM in terms of PGV and significant duration (Ds 595). Our results suggested that the AM was unable to fully capture the simulated ground motion variability mainly due to the incorporation of super-shear rupture and effects of local sedimentary structures. We also showed that an imported GMM considerably deviates from simulated ground motions. This work sets the basis for future development of a comprehensive GMM for Israel, accounting for local source, path, and site effects.