STUDIES OF THE EFFECT OF DEPTH OF FOCUS ON SEISMIC PULSES: ESTIMATION PROCEDURE FOR FOCAL-DEPTH DETERMINATION OF SEISMIC DISTURBANCES
Abstract
A new data processing technique is suggested to estimate the delay time between initially uptraveling energy which is reflected once at the earth's surface and initially downtraveling energy on earthquake seismograms. The method uses optimum inverse filters together with a criterion that measures the simplicity of a seismic signal convolved with an inverse filter. The technique was applied to band-limited synthetic signals that contained several primary- secondary pairs in the presence of random noise. Of 27 synthetic signals which were analyzed, the procedure successfully selected the correct delay time in 22 cases. Four actual earthquake seismograms were then analyzed. The procedure selected a delay time for each earthquake. Focal depths computed from the selected delay times appeared quite reasonable when compared with depths for the same earthquakes published by the United States Coast and Geodetic Survey. In all cases, the inverse filter designed for the selected delay time considerably simplified the original seismogram. It is concluded that the technique provides a reasonable estimate of the delay time between primary and surface reflected energy.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 08, 1964
- Accession Number
- AD0607491
Entities
People
- Stephen C. Merdler
Organizations
- Pennsylvania State University