The Application of High-Resolution AVO Inversion for Dolomite Reservoir Identification in Sichuan Basin, China

The study area is located in Central Sichuan, Sichuan Basin in China. The research target is Cambrian Longwangmiao formation, consisting of a set of dolomite reservoir distributed within limestone. However, the gas reservoirs are hard to detect due to strong heterogeneity and rapidly lateral changes of reservoirs. Conventional AVO inversion methods cannot meet the demand for the thin and tight dolomite reservoir identification because of the low resolution and poor accuracy of the algorithm. Especially when it comes to the density, conventional AVO inversion methods often fail to obtain reasonable results. In this paper, AVO inversion scheme is established based on the Bayesian theory and the exact Zoeppritz equations to obtain elastic parameters directly in order to enhance the robustness and accuracy. Synthetic tests and real data application both verify the effectiveness and accuracy of the method and can provide a significant guidance for the further exploration and exploitation of dolomite hydrocarbon reservoirs in the study area.