RESUMO
In the present paper the source process of some large earthquakes occurred in Greece is discussed in terms of the distribution of the asperities or barriers on the fault plane. The source process has been revealed by the inversion of teleseismic long period body waves using two different techniques. Based on the obtained source time functions an attempt is made to explain the low stress drop values for the earthquakes occurred in Greece. It seems that the stress drops computed by using Brune's model are an average estimate and do not reflect to some seismotectonic characteristics of the focal region
Assuntos
Terremotos , Geologia , Métodos de Análise Laboratorial e de Campo , Grécia , Moldes Genéticos , Sistemas ComputacionaisRESUMO
One of the most important developments in the understanding of the earthquake source in the last years is the documentation of the complexity of earthquake source. Numerous studies, based on teleseismic and near field data, have revealed that small areas of higth stress drop are embedded in larger, low stress areas. The higth frequency content of the strong ground motion comes from these small areas, although they contribute only a fraction of the total seismic moment. (AU)
Assuntos
Terremotos , Medição de Risco , Desastres NaturaisRESUMO
Teleseismic P-waves are utilized to estimate the seismic moment M o, source dimension r, fault length 1, average displacement , stress drop, radiated energy Es, and apparent stress n