The Benefit of TTI Reverse Time Migration for Subsalt Imaging, Gulf of Mexico

In reverse time migration (RTM), the wave propagation is based on directly solving the two-way wave equation. Thus RTM provides a natural way to deal with large lateral velocity variation and imposes no dip limitations on the images, and it becomes a standard migration tool for subsalt imaging in Gulf of Mexico. On the other hand, recent advances in wide azimuth (WAZ) and multi-azimuth (MAZ) data acquisition provide more azimuth information, which offers better opportunities for estimation of anisotropy parameters, and improves images under steeply-dipping anisotropy overburdens. This requires RTM to handle general anisotropy media, especially tilted transverse isotropy (TTI) to achieve a significant improvement in image clarity. We demonstrate in this paper, particularly in the Gulf of Mexico, using TTI reverse time migration can produce better subsalt images.