Velocity analysis for transversely isotropic media

The main difficulty in extending seismic processing to anisotropic media is the recovery of anisotropic velocity fields from surface reflection data. The paper suggests carrying out velocity analysis for transversely isotropic (TI) media by inverting the dependence of P-wave moveout velocities on the ray parameter. The inversion technique is based on the exact analytic equation for the normal-moveout (NMO) velocity for dipping reflectors in anisotropic media. The performance of the velocity-analysis method is shown not only on synthetic, but also on field data from offshore Africa. Generalization of the single-layer NMO equation to layered anisotropic media with a dipping reflector provides a basis for extending anisotropic velocity analysis to vertically inhomogeneous media. -from Authors