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Inversion of seismic refraction data in planar dipping structure

Bernd Milkereit·Walter D. Mooney·W.M. Kohler
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Abstract

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.

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Bernd Milkereit, Walter D. Mooney, W.M. Kohler. 1985. Inversion of seismic refraction data in planar dipping structure. https://doi.org/10.1111/j.1365-246x.1985.tb05129.x

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