Simulated 2D/3D PSDM Images With a Fast, Robust, And Flexible FFT-based Filtering Approach.

The “Simulated Prestack Local Imaging” method simulates Prestack Depth Migrated sections directly from angledependent reflectivity grids, without needing prestack synthetic traces (SimPLI, patent pending). Ray tracing techniques are used to generate, in a background model, scattering wavenumbers, i.e., the mandatory information for SimPLI. From that information, 2D/3D filters are built and the simulation process consists of applying these filters to reflectivity grids in the wavenumber domain. PSDM images are then obtained in space using FFT. The process is fast, robust and flexible, and is an extension of 1D convolution techniques in time-domain, but with 2D/3D convolution directly in space-domain. The filters built from the scattering wavenumbers contain lots of information such as the pulse, the overburden effects on the illumination of the targets, and 2D/3D resolution effects. Applications of SimPLI are multi-fold, with, among others, survey planning, interpretation analyses, and 4D seismics.