Modeling Method of Braided River Delta Reservoir Configuration Based on Flow Unit

The complex fault block oilfield in Weixinan Sag is gradually entering the middle and late development stage and the middle and high water cut stage. The complex contradictions among layers, within layers and in the plane result in low efficiency of injection water waves, complex distribution of oil and water, and difficult to accurately predict the distribution of remaining oil. The fine characterization of the internal configuration of the reservoir was carried out to characterize the strong heterogeneity of the continental sedimentary complex fault block reservoir, and the flow unit was subdivided to qualitatively characterize the differences in the reservoir quality of sand bodies at different stages in the vertical direction of the reservoir, which brought new challenges to the fine geological modeling of the reservoir. In view of the lack of well data in offshore oil fields, sedimentary laws and geological knowledge base summarized in previous studies are used to constrain the modeling of braided river delta reservoir configuration. Taking Weizhou C Oilfield as an example, sequential indication, object, truncated Gauss Multipoint geostatistics isophase modeling method is preferred to establish underwater distributary channel model based on target method. The truncated Gaussian simulation method can effectively characterize the characteristics of the transition zone, establish the flow unit model, use the flow unit constraint attribute model to establish, further calculate the reservoir heterogeneity coefficient, accurately characterize the reservoir heterogeneity, and lay a good foundation for the next step of reservoir numerical simulation and tapping the potential of remaining oil.