f Anti-aliasing and amplitude preserving 2D and 3D DMO - some practical considerations

Amplitude Preserving or True Amplitude DMO is needed to avoid arbitrary attenuation of dipping events when mapping pre-stack data to zero offset and is an invaluable tool in the study of AVO (Amplitude-Versus-Offset) effects . One of the major drawbacks of integral DMO methods has been their inability to preserve the amplitudes of dipping events. This can be attributed to the fact that inadequate or sometimes, no anti-alias filtering techniques have been applied in the implementation of the DMO time shifting part. To mitigate the effects of operator aliasing amplitude weighting factors have been applied which result in the attenuation of dipping events in the mapping to zero offset. In addition, such algorithms failed in the requirement of being a "do-nothing" operator for horizontal events.