Angle domain common image gathers for steep reflectors

Abstract:

Downward continuation migration cannot provide reliable angle domain common image gathers (CIGs) for steeply dipping reflectors, because it cannot handle most waves that illuminate steep reflectors. Also there is a severe stretch in conventional horizontal subsurface offset at steep reflectors. Both reverse-time migration and plane-wave migration in tilted coordinates solve these two problems and provide robust angle domain CIGs for steeply dipping reflectors. A test on the BP velocity benchmark dataset shows that both migration methods generate robust angle domain CIGs that are comparable. When the migration velocity is not correct, the angle domain CIGs from both migration methods show useful moveout information for velocity estimation.