Source processes and spectral ground motion models of intermediate depth Vrancea (Romania) earthquakes

Abstract

For successful assessment and mitigation of earthquake hazards, it is necessary to be able to reliably predict the level of ground shaking which has to be expected from future large earthquakes. This prediction of ground motion can be done either by using empirical relations (derived from past earthquakes) between some ground motion parameter and the source and observer location, so-called attenuation relations, or by performing numerical simulations of future earthquakes based on models of the earthquake source and the propagation medium (i.e. the Earth). The capacity of the first option is at times rather limited, for instance if only very few large earthquakes occurred in the region of interest in instrumental times. Numerical simulations, on the other hand, cannot provide reliable results without a detailed description of the underlying source process and a thorough understanding of path and site effects. This thesis aims at a better understanding of the source process and the spectral characteristics of the intermediate-depth Vrancea (Romania) earthquakes...