This study aims to simplify the quasi-P (qP) wave equation from the elastic wave equation in Horizontal Transverse Isotropy (HTI) media, thereby enabling more accurate anisotropic wavefield simulation in fractured media. Based on the finite difference method, we implement the new 3D anisotropic wavefield simulation using the extended SEG HESS model, and observed different wavefield propagation characteristics in VTI and HTI media.
The research extends into practical application through a detailed case study in a shale gas exploration area in Sichuan, China. Here, a complex 3D model incorporating various strata and fracture zones was designed based on well logs and seismic interpretations. This model served as a foundation for executing wavefield simulations and imaging, aiming to unravel the intricate fracture seismic response within the Wufeng Formation. We applied anisotropic prestack depth migration(PSDM) to a total of 1271 shots data, which facilitated understanding the seismic response on fractured blocks and distinguishing the seismic characteristics of different fracture densities and fillings. Finally, the optimized attributes are effective in predicting fractures in the Sichuan survey.
