Gaussian beam depth migration for anisotropic media

Gaussian beam migration (GBM) efficiently handles isotropic inhomogeneous media. The approach is based on the solution of the wave equation in ray-centered coordinates. Here, the method is extended to work for 2-D migration in generally anisotropic inhomogeneous media. Extension of the Gaussian-beam method from isotropic to anisotropic media involves modification of the kinematics and dynamics in the required ray tracing. Ray tracing in anisotropic media is much slower than that in isotropic media. However, because ray tracing is just a small portion of the computation in GBM, the increased computational effort in general anisotropic GBM is typically only about 40%. Application of this method to synthetic examples shows successful migration in inhomogeneous, transversely isotropic media for reflector dips up to the beyond 90°. -from Author