f 3D prestack depth migration on a massively parallel computer: implementation and case history

3-D prestack depth migration is a viable imaging process when implemented on a massively parallel computer. We describe the implementation of a Kirchhoff-based 3-D prestack migration algorithm on an Intel iPSC/860 supercomputer and how the parallel architecture of such machines is used to speed up computations. A comparison of a 3-D prestack depth migration with a 2-D prestack depth migration on a field-data salt imaging problem underscores the perils of 2-D prestack depth migration in imaging complex structure .