Comparison of Deterministic and Geostatistical Inversion Results - A Case Study for a Gas-saturated Reservoirs with Coals

In this paper, we discuss a comparison of deterministic and geostatistical inversion approaches to reservoir characterization of a complex gas-saturated clastic reservoir with thin coal beds. This reservoir type is characterized by high acoustic contrasts which present challenges for inversion techniques. To overcome these challenges in deterministic inversion, a methodology was applied to update the low frequency model in an iterative manner. This method improves the accuracy of elastic properties prediction which was verified with data from 28 newly drilled wells. Furthermore, it proves that for quantitative reservoir characterization, the application of AVO/AVA geostatistical inversion is recommended.