Summary
Reverse-time migration applied to shot gathers, has typically outputs stacked images. This does not allow for the use of the multi-dimensionality of the data after imaging. For todays wide- and full-azimuth acquisitions this imposes a strong limitation on our ability to fully utilize the data quality and subsurface illumination such surveys offer.
Here, we present an implementation of reverse-time migration that allows for the output of azimuth-sectored angle gathers in all CDP locations in the image space. These 3D angle-gathers are virtually artifact free as we use an inverse scattering imaging condition that effectively removes the backscatter noise during the imaging step. With access to angle gathers for the whole image volume, we can deploy conventional strategies of muting, editing, noise suppression and residual corrections before stacking, leading to much improved images in both extra-salt and complex sub-salt regions.
