Wavefield separation in transversely isotropic medium: A plane-wave decomposition approach
Lawrence H. T. Le, Donald T. Easley, Robert R. Stewart
Devaney and Oristaglio (1986) described a method to decompose a two-dimensional elastic vector wavefield into compressional (P) and shear (S) waves for homogeneous isotropic layered structure. By two-dimensional wavefield, it is assumed that the disturbance is generated by a line source of infinite length. The method can be extended to a transversely isotropic (T.I.) material with a vertical axis of symmetry. In this case, the wavefields to be separated are quasi P- and quasi S-waves. The method is applicable to an array of receiver in both vertical and horizontal directions provided that the phase velocities are known in any direction. This is similar to the acquisition geometry of VSPs and surface seismic data respectively.