Determination of Source Depth by Spectral, Pseudo-Autocovariance, and Cepstral Analysis.
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)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 24, 1969
- Accession Number
- AD0848100
Entities
People
- T. J. Cohen
Organizations
- Teledyne Technologies