Pre-stack Reverse-time Migration Using Triangular Grid Based Finite Difference Method

Compared with other migration methods, reverse-time migration is based on precise wave equation, not an approximation, and performs wave extrapolation in the time domain rather than the depth domain. It is highly accurate and not affected by strong subsurface structure complexity and horizontal velocity variations. The difference method based on triangular grids maintains the simplicity of the difference method and the precision of the finite element method. It can be used directly for forward modeling on models with complex top surfaces and migration without statics preprocessing. We have applied a finite difference method based on triangular grids for pre-stack reverse-time migration. Tests on model data verify that the method introduced here can achieve perfect results in application.