Accession Number : AD0627616

Title :   AFTERSHOCK SEQUENCE AND CRUSTAL STRUCTURE IN THE REGION OF GREECE.

Descriptive Note : Annual summary rept. no. 1, 1 Jun 64-31 May 65,

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

Personal Author(s) : Galanopoulos,A. G. ; Papazachos,Basil C.

Report Date : 31 MAY 1965

Pagination or Media Count : 7

Abstract : The object of this study was to determine the wave velocities of body waves, to attempt to calculate the average thickness of the crust and to have an estimation about the change of the thickness of the crust from place in the region considered. The first problem was to identify the most prominent phase and find their travel time curves. Different procedures were followed to determine the travel time curves for epicentral distances between 0 and 150 km and for epicentral distances between 200 and 1000 km. By using data from 250 earthquakes with epicenters near the station of Athens, the velocities of the direct P and S waves were found to be equal to 5.25 km/sec. and 3.19 km/sec, respectively. The determined mean focal depth of these earthquakes is 7 km. By using data from about 1000 earthquakes with epicenters in the region of Greece the most prominent phases for epicentral distances between 0 and 1000 km were identified. Their travel time curves were also determined.

Descriptors :   (*SEISMOLOGY, GREECE), (*GREECE, SEISMOLOGY), (*STRUCTURAL GEOLOGY, GREECE), EARTHQUAKES, SEISMIC WAVES, EPICENTERS

Subject Categories : Geology, Geochemistry and Mineralogy
      Seismology

Distribution Statement : APPROVED FOR PUBLIC RELEASE