Interpretation of Angle Gathers For Transversely Isotropic Medium

Mallick, Subhashis (Chevron Energy Technology Company)



Reservoir seismic applications require offset domain seismic data to be converted into angles. While it is straightforward to convert offsets to angles under the isotropic assumptions, such a transformation is complex in the presence of anisotropy. Correct interpretation of angle dependent reflection amplitudes requires offset domain data to be corrected for the non-hyperbolic anisotropic moveout and distinction between the phase and the group angles. Some of these fundamental issues relating to the angle dependent P-wave seismic reflections for transversely isotropic elastic medium with a vertical symmetry axis (VTI medium) are reviewed here with illustrations.