Common-opening-angle migration/inversion: a Kirchhoff inversion approach

摘要

We derive a Kirchhoff migration/inversion technique here as an integral over migration dip at an output point at depth with fixed opening angle between rays from source and receiver. This abstract gives only the final acoustic formulas Thus, this is a common angle migration/inversion. This method has the advantage of dealing more routinely with multipathing of rays than do common offset or common shot migration/inversions. Previous derivations of this method are couched in the language of generalized Radon theory and pseudo-differential operator/Fourier integral operator theory or in least squares inversion methodology. The derivations here arise from more classical Kirchhoff inversion theory, hopefully more accessible to the geophysical community. Further, the inversion formulas of the earlier work are always presented for the most general anisotropic elastic medium. This abstract only states the final acoustic formulas for which a brief derivation will be provided in the talk. We also present simplified formulas for processing data from the upper surface as integrals over all sources and receiver, carrying out a suite of common-opening angle inversions in parallel.