Accession Number : AD0848100

Title :   Determination of Source Depth by Spectral, Pseudo-Autocovariance, and Cepstral Analysis.

Descriptive Note : Seismic data lab. rept.,

Corporate Author : TELEDYNE INDUSTRIES INC ALEXANDRIA VA EARTH SCIENCES DIV

Personal Author(s) : Cohen, T. J.

Report Date : 24 JAN 1969

Pagination or Media Count : 39

Abstract : Interference of P (or Pn) and pP (or pPn) produce scalloped spectra with a null period equal to the depth-phase time delay tau. Determination of the null-frequency (f = 1/tau), together with a knowledge of the overburden compressional velocity, permits an estimate of the source depth. Scalloping produced by station site structures is reduced by averaging a suite of station spectra. Further, the spectral band available for analysis is broadened by removing instrument response. To objectively determine periodicities in the average spectrum, the cepstra and pseudo-autocovariance are computed. The depth determination method employing spectral, pseudo-autocovariance, and cepstral analysis is applied to nine Pn and P data sets for five underground explosions. Five sets yielded reasonable estimates of the shot depth. (Author)

Descriptors :   (*SEISMOLOGICAL STATIONS, DATA PROCESSING), (*UNDERGROUND EXPLOSIONS, DETECTION), POWER SPECTRA, NUCLEAR EXPLOSIONS, SEISMIC WAVES, DEPTH FINDING, SAMPLING, FUNCTIONS(MATHEMATICS), COMPUTER PROGRAMMING, ENERGY, SOURCES, CORRELATION TECHNIQUES, COMPUTER PROGRAMS.

Subject Categories : Seismology
      Computer Programming and Software
      Seismic Detection and Detectors

Distribution Statement : APPROVED FOR PUBLIC RELEASE