Inversion of Surface Waves for Path Structure and Attenuation

Abstract : We have developed and tested a set of three computer programs which yield path correction estimates from surface wave observations. The sequence of steps involved in estimating travel path effects on phase and amplitude of a surface wave are: Retrieval of phase and group velocity dispersion curves from the seismogram by phase matched filtering; extraction of spectral amplitudes by narrow-band filtering; removal of multipath arrivals; Inversion of dispersion curves in terms of an average structure along the path; Calculation of synthetic seismograms from the average structure; and Estimation of source moment and attenuation function from synthetic/observed spectral ratios.