Numerical methods for the migration of constant‐offset sections in homogeneous and horizontally layered media

Publisher Website
Google Scholar
Abstract
This paper describes schemes for the frequency‐domain migration of constant‐offset sections in homogeneous and horizontally layered media. Their main advantage is that individual constant‐offset sections can be processed in isolation. The basis for these schemes is a generalization of the following plane‐wave analysis of migration for the zero‐offset case. Migration can be viewed in the time domain as a process whereby the plane waves echoed from a source to a geophone by a reflecting point are shifted in time to a common intersection. The shift applicable to each plane wave can be derived from the knowledge of the diffraction curve for the reflecting point in a neighborhood of the geophone abscissa. This time shift in turn determines the phase shift applicable in the frequency domain to the associated Fourier component of the seismic section. The central part of our methods is the construction of those elements of the diffraction curve pertinent to the shifts from the velocity map of the time section. The result is a table of shifts for an appropriate sample of plane‐wave directions, to be used for interpolation in the migration process. The effectiveness of the method is illustrated by computer experiments with synthetic data.

This publication has 0 references indexed in Scilit: