Use of LP Surface Waves for Source Characterization

• Published in: Geophysical Journal International
• Main Author: Tsai, Yi-Ben
• Format: Text
• Language: English
• Published: Oxford University Press 1972
• Subjects: Articles; Arctic; Arctic Ocean
• Online Access: http://gji.oxfordjournals.org/cgi/content/short/31/1-3/111; https://doi.org/10.1111/j.1365-246X.1972.tb02362.x

The complex cepstrum technique is found to provide an effective means for removing undesirable modulations of surface wave spectra caused by interference of either multiple sources or multipath propagation. This technique has greatly enhanced the utility of surface wave spectra for characterization of seismic sources. An empirical analysis of surface wave spectra on a regional basis is made on seismic events in the Arctic Ocean and the Eurasian Continent. The results indicate that: (1) the spectral shapes of Rayleigh waves often are similar among events in the same epicentral area but vary substantially from one epicentral area to another, (2) a great majority of earthquakes can be differentiated from underground nuclear explosions based on spectral shapes of Rayleigh waves, and (3) spectral shapes of Love waves do not vary as much as Rayleigh waves from one epicentral area to another. Finally, a method for systematically finding the source mechanism and focal depth of an earthquake using the observed and theoretical surface wave spectra are devised and tested. The results from tests of the method on several earthquakes are consistent with other independent evidence.