SEISMIC HAZARD ASSESSMENT IN THE BROADER AEGEAN AREA USING TIME-INDEPENDENT SEISMICITY MODELS BASED ON SYNTHETIC EARTHQUAKE CATALOGS

Abstract

In order to evaluate the seismic hazard for the broader Aegean area, a modified timeindependent seismicity model is used. A Monte-Carlo procedure has been employed to create synthetic earthquake catalogs with specific characteristics regarding their time, space and magnitude distributions. Moreover, particular geometrical characteristics, such as subducting and oblique seismic zones are also taken into account in the synthetic catalogs generation. A significantly revised earthquake catalog, all available fault plane solutions and information on the seismotectonics of the broader Aegean area were considered in order to propose a new updated model of seismic zones for this area. Seismicity parameters for the new seismic zones were calculated and the corresponding synthetic earthquake catalogs were generated using the proposed procedure. The distribution of the expected values for ground motion parameters (e.g. PGA, PGV) was estimated using synthetic catalogs for several sites of interest, by performing computations directly on all earthquakes of each catalog. Computations were performed for a dense grid of sites and seismic hazard estimates were determined both directly from the peak ground motion distribution, as well as from fitted extreme values Gumbel distribution. Ground motion parameters were also calculated using classic seismic hazard assessment algorithms (EqRISK), in order to evaluate the compatibility of the proposed method with conventional approaches.