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Three-parameter AVO crossplotting in anisotropic media

Chen Hao·J.P. Castagna·R.L. Brown·A.C.B. Ramos
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Abstract

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.

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Chen Hao, J.P. Castagna, R.L. Brown, A.C.B. Ramos. 2001. Three-parameter AVO crossplotting in anisotropic media. https://doi.org/10.1190/1.1487081

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