Prestack migration deconvolution+AVO inversion

Measuring reflection amplitude versus offset (AVO) has proved to be effective in reservoir characterization. Experience shows that AVO inversion methods based on amplitude-preserved prestack migration typically provides a more accurate lithology estimate than NMO-based AVO analysis. However, some artifacts may be introduced into the migration section due to an undersampled acquisition geometry, a limited recording aperture, and strong velocity contrasts, which can obscure the estimate of reservoir properties. Here, we investigate the impact of migration deconvolution (MD) on amplitude fidelity, AVO analysis and inversion. The MD method is applied to images migrated from common offset sections and shows improved spatial resolution and imaging quality. Together with angle gathers generated from prestack true-amplitude migration, the AVO parameters are inverted using MD common reflection gathers (CRG). Tests results indicate that MD is capable of preserving the relative amplitude variation along offset. Additionally, examples with synthetic and field data clearly demonstrate that MD improves the imaging quality of CRGs; furthermore, AVO parameter sections are optimized for interpretation and anomaly identification.