Fine Structure Interpretation and Favorable Reservoir Prediction of the Tsagaan‐Tsav Formation in the Step‐fault Zone of Chaxi

10.6911/WSRJ.202206_8(6).0114

Zuohang Liu

Tsagaan‐Tsav Oilfield ； the step‐fault zone of Chaxi ； Tsagaan‐Tsav formation ； Fine structure interpretation ； Reservoir prediction

World Scientific Research Journal

8卷6期（2022 / 06 / 01）

866 - 875

英文

Aiming at the problems of unclear structural characteristics and unclear reservoir distribution of Tsagaan‐Tsav formation in the step‐fault zone of Chaxi. Based on the data of mud logging, logging and the seismic and related information, a comprehensive use of various technical means, such as connected wells facies, seismic facies, sedimentary facies, seismic attribute analysis, seismic wave impedance inversion and stratum slices, etc., were used to deeply study the structure interpretation and reservoir prediction in the study area. The results show that the step‐fault zone of Chaxi is a NW dipping fault block structure. Many small faults are developed in the fault block, but they all belong to normal faults. The main strike of the fault is NNE. The single layer of the reservoir is thin, and the main lithology is siltstone. The wave impedance analysis of single well sandstone and mudstone is completed. The impedance value of sandstone in the main target interval is greater than 10400g/cm3*m/s, and the impedance value of mudstone is less than this value. In view of the difficulty of thin reservoir thickness in the target area, in the inversion process, the technical sequence combining frequency division technology and Bayesian seismic inversion technology is used to complete wave impedance inversion, so that the reservoir identification ability can reach 10m or even 5m from 56m of seismic data, which basically meets the requirements of favorable sand formation reservoir description in the study area. It has important guiding significance for the further development of the study area.