Accession Number : AD0641160

Title :   FORESHOCK AND ATERSHOCK SEQUENCES OF SOME LARGE EARTHQUAKES IN THE REGION OF GREECE,

Corporate Author : NATIONAL OBSERVATORY OF ATHENS (GREECE) SEISMOLOGICAL INST

Personal Author(s) : Papazachos,B. ; Delibasis,N. ; Liapis,N. ; Moumoulidis,G. ; Purcaru,G.

Report Date : 01 JUL 1966

Pagination or Media Count : 143

Abstract : Deformation characteristics, magnitude and time distributions of the large aftershocks occurred in the region of Greece from 1926 till 1964 are investigated. An approximate relation between the number of aftershocks and the magnitude and focal depth of the main shock has been found. Also, an approximate relation has been derived between the magnitude of the largest aftershock and the magnitude and focal depth of the main shock. The largest aftershock occurs within fourteen days after the main shock. In many cases large 'late aftershocks' occur one or more months after the main shock. One or more foreshocks of magnitude larger than 3.8 occurred in forty per cent of the cases. The probability for an earthquake to be preceded by a large foreshock not much smaller than the main shock is 10%. It is shown that some properties of the earth's material in the aftershock region can be derived by studying the magnitude distribution and deformation characteristics of the aftershocks. (Author)

Descriptors :   (*EARTHQUAKES, GREECE), SEISMIC WAVES, SEISMOLOGY, DEFORMATION, DISTRIBUTION

Subject Categories : Seismology

Distribution Statement : APPROVED FOR PUBLIC RELEASE