A comparative study of a stochastic and deterministic simulation of strong ground motion applied to the Kozani-Grevena (NW Greece) 1995 sequence

Abstract

We present the results of a comparative study of two intrinsically different methodologies, a stochastic one and a deterministic one, performed to simulate strong ground motion in the Kozani area (NW Greece). Source parameters were calculated from empirical relations in order to check their reliability, in combination with the applied methodologies, to simulate future events. Strong ground motion from the Kozani mainshock (13 May, 1995, M w = 6.5) was synthesized by using both the stochastic method for finite-fault cases and the empirical Green’s function method. The latter method was also applied to simulate a Mw = 5.1 aftershock (19 May, 1995). The results of the two simulations computed for the mainshock are quite satisfactory for both methodologies at the frequencies of engineering interest (> ~ 2 Hz). This strengthens the idea of incorporating proper empirical relations for the estimation of source parameters in a priori simulations of strong ground motion from future earthquakes. Nevertheless, the results of the simulation of the smaller earthquake point out the need for further investigation of regional or local, if possible, relations for estimating source parameters at smaller magnitude ranges