GLOBAL SOURCE PARAMETERS OF FINITE FAULT MODELFOR STRONG GROUND MOTION SIMULATIONS OR PREDICTIONS

摘要

Global source parameters of finite fault model are important in strong ground motion simulations orpredictions near field. In this paper, theoretical relationships between moment magnitude and globalsource parameters of finite fault model including subsurface rupture length, downdip rupture width,rupture area, and average slip on the fault plane are deduced based on seismological theory. Thesetheoretical relationships are further simplified by applying similarity conditions, and an unique form isestablished. Then, combining the simplified theoretical relationships between moment magnitude andglobal source parameters with seismic source data selected in this study, some practical semi-empiricalrelationships are established. The seismic source data selected is also used to derive empiricalrelationships between moment magnitude and global source parameters by the ordinary least squareregression method. Comparisons between semi-empirical relationships and empirical relationships showthat the former depicts distribution trends of data better than the latter. It is also observed that downdiprupture widths of strike slip faults are saturated when moment magnitude is more than 7.0, but downdiprupture widths of dip slip faults are not saturated in the moment magnitude ranges of this study.