The control effect of injection-production relationship and configuration mode of meandering river on remaining oil distribution in ultra-high water cut stage

The sand body of meandering river reservoir has strong heterogeneity and developed barrier body. The distribution of remaining oil in ultra-high water cut stage is affected by the coupling effect of static constraint of reservoir configuration and dynamic regulation of injection-production relationship, which has become the core bottleneck of oil recovery improvement. In this paper, the meandering river reservoir is taken as the research object, and the quantitative prediction model of the dip angle of the lateral accretion layer and the typical model of Ng35 and Ng44 point bar in Gudong Oilfield are established by referring to the statistical regression results of modern river geomorphic parameters. Through numerical simulation, the effects of static configuration factors such as the number of lateral accretion layers and permeability, as well as dynamic injection-production factors such as well pattern and well type on the distribution of remaining oil are systematically analyzed, and the remaining oil distribution patterns of typical configurations such as layered non-stacking type, point stacking type and heterogeneous lateral splicing type are studied. The main controlling factors and distribution rules of the remaining oil distribution in the meandering river reservoir are clarified, and the remaining oil distribution modes under different configuration modes and injection-production relations are established, which provides an important geological basis and technical reference for the potential tapping and efficiency increasing of the remaining oil in the extra-high water cut stage of the meandering river reservoir.