ASA 130th Meeting - St. Louis, MO - 1995 Nov 27 .. Dec 01

4pSP2. The use of surface wave dispersion for source ranging.

Jason T. Penshorn

Randall W. Smith

Appl. Res. Labs., Univ. of Texas, 10,000 Burnet Rd., Austin, TX 78713

Surface wave dispersion curves (velocity versus frequency curves) are used to estimate source range. The data used in this study consist of signals, due to an impulsive source, received on a line array of triaxial seismometers. The first step in the ranging method is the estimation of the surface wave dispersion curve. This is accomplished via the use of the continuous wavelet transform as a time-frequency decomposition. The known dispersion curve is then used in conjunction with the time-frequency decomposition of the received signal to estimate source range. The method and some preliminary results were presented previously [Smith et al., J. Acoust. Soc. Am. 97, 3310(A) (1995)]. This presentation focuses on the effects of receiver separation and signal-to-noise ratio on the ability to accurately estimate the surface wave dispersion curve, and the corresponding effects on the source range estimates.