Three-parameter AVO crossplotting in anisotropic media
Amplitude versus offset (AVO) interpretation can be facilitated by crossplotting AVO intercept ( A ), gradient ( B ), and curvature ( C ) terms. However, anisotropy, which exists in the real world, usually complicates AVO analysis. Recognizing anisotropic behavior on AVO crossplots can help avoid AVO interpretation errors. Using a modification to a three-term ( A , B , and C ) approximation to the exact anisotropic reflection coefficients for transversely isotropic media, we find that anisotropy has a nonlinear effect on an A versus C crossplot yet causes slope changes and differing intercepts on A versus B or C crossplots. Empirical corrections that result in more accurate crossplot interpretation are introduced for specific circumstances.