Tracing Seismic Shortest Path Rays in Anisotropic Medium with Rolling Surface

Abstract

AbstractIt has very important theoretical and practical values to take rolling surface and seismic anisotropy into consideration in seismic forward modeling and inversion. Based on previous researches, the shortest path calculation algorithm is introduced in this paper to calculate seismic travel times in anisotropic media with rolling surface. In the process of model gridding, the whole model is divided into square cells firstly and rolling boundary is regarded as the approximation of units with irregular shapes. Then shortest path calculation is achieved on irregular grids by setting irregular nodes. Sena's group velocity approximation is used to calculate seismic travel times in anisotropic media during ray tracing, and seismic shortest path ray tracing in a complex anisotropic medium with rolling surface is achieved in the end. Theoretical model calculations show that the method in this paper can be reliably applied to complex anisotropic models with higher calculation accuracy.