Automatic Seismic Signal Processing Research.

Abstract : This report describes computer programs implemented on the Seismic Data Analysis Center computer system for automatically analyzing seismograms and classifying them as being either explosion-like or earthquake-like. The principal accomplishments of this work have been (1) the development at SDAC of a library of general purpose data analysis programs, (2) the definition of an event-oriented waveform data base (3) the development of a program to measure spectral ratios, body-wave magnitude, surface wave magnitude and complexity automatically, and (4) the re-analysis of the variable frequency magnitude (VFM) data compiled during the Area of Interest (AI) experiment using linear discriminant analysis. Although successful performance of the discrimination software has been demonstrated in both an interactive and automatic mode, intensive testing and evaluation will require three further steps. The first of these is to incorporate automatic procedures for measuring time-domain m sub b and M sub s measures. The second is to expand greatly the size of the data base. The third is to process the augmented data set for all discriminants and use these as training data in a more complete linear discriminant analysis. (Author)