Accession Number : AD0637674

Title :   SEISMIC MAGNITUDE AND SPECIFIC ABSORPTION COEFFICIENT IN THE IBERIAN REGION.

Corporate Author : INSTITUTO GEOGRAFICO Y CATASTRAL MADRID (SPAIN)

Personal Author(s) : Munuera,J. M.

Report Date : JUL 1965

Pagination or Media Count : 16

Abstract : In the report is presented the magnitude scale used by Spanish Seismological Survey (SSS) for near earthquakes inside the area 5 degrees E-10 degrees W, 35 degrees-44 degrees N, which has been deduced from shear waves and with an explicit term for the specific absorption. The way for computation this coefficient is the difference between a theoretical expression for log E and other empirical one, which was previously determined for the Toledo Observatory. The method requests this base-station, besides the new standard calibration made for the other four stations handled and also abundant events and the corresponding m values as preliminary deduced by Laboratorio Central del Servicio de Sismologia (LCSS), Madrid, since 1961 up to 1964. We have obtained Q=(62.5 delta degrees + 67) plus or minus 32 for 1.5 < or = delta degrees < or = 7.5; the average Q=300 is assumed for the whole crust in the said area. (Author)

Descriptors :   (*SPAIN, *SEISMOLOGY), (*EARTHQUAKES, SPAIN), ATTENUATION, SEISMIC WAVES, INTENSITY, CLASSIFICATION

Subject Categories : Seismology

Distribution Statement : APPROVED FOR PUBLIC RELEASE