Efficient imaging aperture criterion for reduction of computational cost of TTI RTM

Seismic migration is an important step in conversion of seismic data into a subsurface image. The cost of the migration depends upon the choice of migration algorithm, dimensionality of space or time and the medium properties. There are range of migration methods exists today. Among all the approaches the two way wave equation based RTM (Reverse Time Migration) migration is found to be most accurate in terms of dealing with complexity of the medium. RTM complexity and cost increases as be go from isotropy to anisotropy medium. The wave equations invloved in solving a TTI (Tilted Transverse Isotropic) RTM are much more complex than the VTI ( Vertically Transverse Isotropy) RTM or a ISO (Isotropic) RTM. Additionally, the parameter controlling the cost factor of individual shot migration is the imaging aperture. A good aperture is essential for accurately imaging subsurface features. In this paper we are demonstrating the implementation of 2D TTI RTM using different aperture criterion. We have studies the compute resource difference for various aperture methods and accuracy of TTI results using BP TTI model and field data.