1. In a process for generating an image of a subsurface earth formation using marine seismic techniques in which recorded seismic data representing signals acquired by deploying seismic sensors and a seismic energy source, actuating the source and detecting seismic energy reflected from the subsurface in response thereto with the seismic sensors, the reflections from which are captured in the recorded seismic data for use in generating the image, the specific improvement consisting of: transforming the recorded seismic data into the wavenumber-frequency domain; generating three-dimensional numerical solutions to an exact relationship for a three dimensional dispersion relationship of seismic energy traveling through the subsurface earth formation, the numerical solutions calculated using a pre-computed table including selected input values of polar angle and azimuth angle of a transverse isotropic axis of symmetry and selected values of Thomsen anisotropic parameters and selected values of a ratio of inhomogeneous medium velocity along the transverse isotropic axis of symmetry to a reference medium velocity, the exact relationship defining wavenumbers for the seismic data in three dimensions; determining coefficients of a two-dimensional Fourier finite difference relationship that result in a best fit of wavenumbers to the three-dimensional numerical solutions for different splitting directions, resulting in a set of coefficients for each splitting direction; and generating an image of the subsurface earth formation by migrating the transformed seismic data using the wavenumbers from the Fourier finite difference relationship and the set of coefficients from each splitting direction, thereby enhancing the image by displaying inclined formation layers of the subsurface earth formation.