Accession Number:

ADA026177

Title:

An Automatic Seismic Detection Algorithm

Descriptive Note:

Technical rept. no. 7

Corporate Author:

TEXAS INSTRUMENTS INC DALLAS EQUIPMENT GROUP

Report Date:

1975-09-03

Pagination or Media Count:

42.0

Abstract:

Fisher and conventional power automatic seismic signal detectors, utilizing threshold adjustment to realize a constant alarm rate, are developed and evaluated on Korean Short-Period Array Data. Detector performance is measured at different alarm rates and integration gate lengths, both with and without a non-causal quality control algorithm and a prefilter. The detectors ability to pick arrival times and event azimuths is analyzed. Frequency wavenumber detectors are designed and evaluated, and the feasibility of implementing the detectors on the Korean Station Processor is investigated. There was no significant difference between Fisher and conventional power detector performance at the same alarm rate, but both were improved with the use of the quality control algorithm and the prefilter. Azimuthal resolution was poor for all detectors, but the detectors were able to pick arrival times satisfactorily. One frequency-wavenumber detector consistently performed better than the others, and it was concluded that this type of detector offers no advantage over the wideband detectors. It was also found that either the Fisher or conventional power detector could be installed at the Korean Seismic Research Station KSRS.

Subject Categories:

  • Seismic Detection and Detectors

Distribution Statement:

APPROVED FOR PUBLIC RELEASE