Distribution and Potential Exploitation Strategy of Remaining Oil in Offshore High Porosity and High Permeability Thin Oil Formation

When the offshore high-porosity and high-permeability reservoir enters the high water-cut stage, it is complicated to determine the remaining oil distribution regulation and potential exploitation strategy under the factors of reservoir rhythm, plane heterogeneity, fault boundary, and longitudinal interlayer. Due to the influence of reservoir rhythm, sand distribution, well network and well interference. To enhance the oil recovery, the reservoirs in the sand was targeted for the study. Combining the production dynamics of the work area and the information from the numerical simulation, the remaining oil distribution were studied in depth. Corresponding adjustment for well tapping strategy was proposed. The layer remaining oil distribution is influenced by the rhyme and the perforated interval, which is mainly enriched in the upper sand body; The planar residual oil distribution is influenced by the sand distribution, well network, perforated interval, which distribution pattern is characterized as “relatively concentrated on the whole”. Well network adjustment can effectively utilize the remaining oil, including sidetracking old wells and infilling new wells. The infilled new wells can realize the effective development of the remaining oil-rich area and form a new injection and extraction correspondence with the surrounding injection wells, and the water content of the sand body rises slowly, which is 5.02% higher compared with the base plan.