FOCAL MECHANISM AND SOURCE TIME FUNCTION OF SELECTED AFTERSHOCKS OF THE EGION 1995 EARTHQUAKE, GULF OF CORINlTH, GREECE

摘要

Numerous aftershocks, which followed the 1995 Egion earthquaKE of magni- tude Ms = 6.2, were recorded by the seismic network PATNET of the University of Patras and by a temporary local network EGINET. The well recorded aftershocks were located by the Patras Seismological Centre, University of Patras. The complete data set, received from the Centre, contains the records of over a hundred events. The spatial distribution of their epicentres forms an E-W elongated cloud with a central cluster and a few stray-away epicentres west and north-west from the cloud. The events from the central cluster, which is the source area of the main shock, that occurred during the first decade of August 1995, were selected for the analysis. Additionally, a few events from the small cluster located west of the main one were also analysed. Altogether, it was possible to perform the moment tensor inversion in the time domain for 29 aftershocks from the main cluster and for 4 events from the small cluster. The selected aftershocks have moment magintude ranging from 1.7 to 3.2. The source time function of the larger events was determined by the empirical Green's function technique. The records of several pairs of large-small aftershocks, close to each other and with similar focal mechanism, were selected for deconvolution. The source time function was recovered for 5 larger aftershocks from the central cluster and for 3 events from the small cluster.