Quantitative Characterization and Adjustment Study of Flow Field in Low Permeability Fault Block Reservoirs

During the water flooding development of oil reservoirs, the uneven flow of subsurface fluids can lead to the development of dominant flow fields, causing the water cut of producing wells to increase and the water injection efficiency to decrease. In response to the problem of uneven displacement caused by the development of dominant flow fields, this study took the low-permeability block reservoir in the 4-1 block of the Nanpu oilfield as an example. Firstly, combining the research literature, six flow field intensity evaluation indicators were screened using the logical analysis method and principal component analysis of dynamic and static reservoir parameters. Then, various methods such as the analytic hierarchy process, coefficient of variation method, entropy method, and CRITIC method were used to determine the weight of each evaluation indicator and the flow fields intensities were calculated programmatically and analyzed by grading to clarify the development status of different-level flow fields in the block. This study considered the influence of multiple factors on flow field development and proposed a quantitative method for flow field characterization applicable to similar reservoirs by combining various indicators screening and weight calculation methods. The research results have important guiding significance for the quantitative characterization of dominant flow fields and the improvement of development efficiency in similar reservoirs.