TRUE-AMPLITUDE MIGRATION TAKING FINE LAYERING INTO ACCOUNT

The central process in wave-equation-based depth migration is inverse wavefield extrapolation. The commonly applied matched filter approach to inverse wavefield extrapolation ignores the angle-dependent amplitu de and phase distortions that are related to fine layering. This may r esult in dispersed images and erroneous amplitude variation with angle of incidence (AVA) effects. ''Power reciprocity'' formulates a relati on between transmitted and reflected wavefields. It provides the basis for a modified matched filter that does account for the aforementione d distortions. The correction term by which the matched filter is modi fied can be derived directly from the reflection data. With this modif ied matched filter, prestack depth migration will yield nondispersed i mages with correct AVA behavior.