METHOD FOR DEVELOPMENT OF OIL DEPOSITS CONFINED TO REEF RESERVOIRS Russian patent published in 2017 - IPC E21B43/20 

FIELD: oil industry.

SUBSTANCE: invention relates to oil industry and is aimed at reducing residual oil saturation during development of oil fields, confined to reef reservoirs. Method comprises extraction of formation fluid through production wells and pumping a working agent through injection wells in cyclic mode. For this purpose, production wells are located in upper roof part of deposit. Injection wells are located in bottom part of deposit. Alternation of periods of collection formation fluid and pumping working agent is performed with time division. Period of pumping provides interruption of production wells. Period of production comprises interruption of injection wells. Duration of cycles is determined based on calculation of material balance, taking into account change - reduction of threshold volume at recovery of formation pressure and rate of change of threshold volume. At specified values of extractions and pumping of formation pressure is not decreased below boundary. Injection of working agent is performed in bottom part of section. After pumping working agent, method comprises capillary-gravitational impregnation. Then at start-up of production wells, extraction of formation fluid is performed.

EFFECT: technical result is higher oil recovery factor.

1 cl, 7 dwg