Residual depth-migration: enhancing dips
Alvin K. Benson
Journal name: Geophysical Prospecting
Issue: Vol 37, No 7, October 1989 pp. 771 - 779
Info: Article, PDF ( 748.5Kb )
Residual migration can correct for migration done with the wrong velocity. The initial migration can be done with a less accurate, fast time-migration algorithm followed by a residual depth-migration operator. This combines the speed and accuracy of different migration schemes.
The residual depth-migration equation can be obtained by an appropriate transformation of a typical finite-difference, depth-migration equation. Since the cheaper, initial time-migration has already partially migrated the data, the residual depth-migration has less work to do than if the depth-migration were done in a single step. As a result, the overall process has increased the speed and reduced the dip limitations associated with typical depth-migration operators. Results on a steeply dipping model demonstrate the validity and usefulness of residual depth-migration.