Inversion of seismic refraction data in planar dipping structure

Abstract

Summary. A new method is presented for the direct inversion of seismic refraction data in dipping planar structure. Three recording geometries, each consisting of two common‐shot profiles, are considered: reversed, split, and roll‐along profiles. Inversion is achieved via slant stacking the common‐shot wavefield to obtain a delay time–slowness (tau–p) wavefield. The tau–p curves from two shotpoints describing the critical raypath of refracted and post‐critically reflected arrivals are automatically picked using coherency measurements and the two curves are jointly used to calculate velocity and dip of isovelocity lines iteratively, thereby obtaining the final two‐dimensional velocity model. This procedure has been successfully applied to synthetic seismograms calculated for a dipping structure and to field data from central California. The results indicate that direct inversion of closely‐spaced refraction/wide‐aperture reflection data can practically be achieved in laterally inhomogeneous structures. Copyright © 1985, Wiley Blackwell. All rights reserved