Further comments on oblique reflectors

John C. Bancroft

In a constant velocity environment, oblique reflectors can be successfully imaged with a special prestack Kirchhoff migration or by including dip moveout processing with a poststack migration that uses modified velocities.

When the velocities vary with depth, the moveout correction portion of the dip moveout may be in error, and the constant velocity assumption of dip moveout is violated. Prestack time migration, that is based on the RMS velocity assumption, does not have these limitation.