Wave equation versus Kirchhoff prestack depth migration of OBC data

Abstract

In areas with complex velocity models, wave equation depth migration has been shown to give significantly better results than the industry standard Kirchhoff depth migration. For very simple velocity models, on the other hand, Kirchhoff depth migration is expected to give similar results as wave equation algorithms. In this paper, we compare Kirchhoff and wave equation prestack depth migration using an ocean bottom cable (OBC) data set from a North Sea area with a velocity model of intermediate complexity. The wave equation depth migration gives better resolution than the Kirchhoff method, but the wave equation algorithm seems not to image the steeply dipping part of the reflectors at large depths as well as the Kirchhoff depth migration. However, this can be an artificial result due to the blurring introduced by the Kirchhoff method.