Evaluation and comparison of Kuster-Toksoz and Xu-Payne rock physic modeling in an Iranian carbonate reservoir

Most rock physic models are developed for sandstone hydrocarbon reservoirs, which differ significantly from carbonate reservoirs. In this study, two rock physic models, Kuster-Toksoz and Xu-Payne, considering the inclusion models, have been investigated in two wells in one of the carbonate reservoirs in south of Iran. The application of both models has been evaluated as effective considering the results of shear and compressional wave velocities extracted from the models compared with the same measured logs in the wells. Moreover, the pore percentage and aspect ratio estimations using inversion process have been made as well as sensitivity analysis for models. In general, the Xu-Payne model provides more relevant results, within the framework used in this study. In fact, the Xu-Payne has improved the Kuster-Toksoz model which is basically a high-frequency model for ultrasonic studies. It means that Xu-Payne approach contains a workflow which is designed to improve Kuster-Toksoz model for carbonates, and thus, the model is used in low frequencies domainssimilar to well log data.