Migração kirchhoff em profundidade de seções de ondas planas

Abstract

We present a migration method for plane wave source data based on the Kirchhoff Integral, Plane wave migration has been employed to Increase the efficiency of the wavefield extrapolation, Point source records are synthesized into a plane wave and the resulting plane wave data can be migrated using the same scheme as the one for conventional shot-record migration, Plane wave migration reduces the migration computation time, because the extrapolation does not need to be done for all the Individual shot records, but only for the constant plane wave sections, Here we have developed a version of the plane wave migration method based on the Kirchhoff Integral, To calculate the traveltimes for the point source and also for plane wave we used a eikonal solver, Once all plane waves section are migrated independently of the others, the final image Is obtained by stacking all common images gathers, Integral methods are easier than the wave equation methods to adapt to different recording geometries and also allow large and small models to be treated in the same way, Also, with the aid of the Asymptotic Ray Theory (ART), Integral methods can be extended to handle arbitrary velocity structures without any dip limitation, In this paper the SEG-EAGE salt model example and a real dataset from Gulf of Mexico are used to test the theory and show that Kirchhoff plane wave depth migration can produce images comparables In quality to those obtained with Kirchhoff migration and also a reduced computation cost when comparable with the Kirchhoff migration of common shot gathers. © 2007 Sociedade Brasileira de Geofísica.