Physically Based Ground Motion Simulation Methodology and Validation with Mid-Sized Marmara Sea Earthquakes

Abstract

In this paper we have two main purposes. The first one is to simulate midsize earthquake recorded in the Marmara region. The region has a geologically complex and heterogeneous crustal structure and we therefore utilize EGF to constrain high frequency wave propagation. We synthesize ground motion for the full wave train on three components, and applied a ‘physics based’ solution of earthquake rupture. The simulation methodology is based on the studies by Hutchings and Wu (1990), Hutchings (1991, 1994). We synthesized seismograms using by 500 different rupture scenarios that were generated by Monte Carlo selection of parameters within a range. The second purpose is to validate synthetic seismogram with real seismogram. To develop credibility of synthetic seismogram in engineering point of view, we follow the methodology presented by Anderson (2003). This methodology proposes a similarity score based on averages of the quality of fit measuring ground motion characteristics and uses a suite of measurements. Because the methodology produces source and site specific synthetic ground motion time histories and goodness-of-fit scores is ‘excellent’ based on Anderson’s score, we concluded that it can be used to produce ground motion to develop or improve seismic codes and standards.