Time-Independent and Time-Dependent Seismic Hazard in Greece Based on Seismogenic Sources

An improved procedure is followed to assess time-independent andtime-dependent hazard for 144 broad sites (cities, towns, villages) of Greece in termsof expected macroseismic intensities at each one of these sites. In this procedureseveral new results are taken into account: source parameters based on new researchwork on seismicity and on other relative information (new regionalization and im-proved seismicity data parameters and anisotropic radiation at the seismic source), anew relation for the attenuation of macroseismic intensities, and the effect of localconditions (site effects) on the strong-ground motion.Analytic relations and tables, determined by this procedure, permit the reliableassessment of time-independent hazard, in terms of macroseismic intensity (in MMscale), peak-horizontal-ground acceleration, and velocity at each one of these 144sites and at any probability level.Time-dependent hazard has been also assessed for these 144 broad sites in Greece,in terms of the probability for the occurrence of strong ground-motion with macro-seismic intensity I $ VII (in MM scale) at each one of these sites during the period1996–2010. Comparison of the assessed time dependent hazard with observed ma-croseismic intensities of the period 1950–1995 indicates that the time-dependentmodel gives very reasonable results.Introduction