METHOD FOR DEVELOPMENT OF OIL LOW-PERMEABILITY DEPOSIT Russian patent published in 2025 - IPC E21B43/17 E21B43/30 

FIELD: mining.

SUBSTANCE: invention relates to oil industry and can be used in development of purely oil deposits with low-permeable reservoirs. Technical task of the proposed method is to increase oil recovery of a low-permeability deposit. Method of developing low-permeability oil deposits includes drilling of horizontal injection and production wells with row arrangement in parallel to each other, separation of horizontal shafts by packers, pumping of working agent into injection wells, product extraction from production wells. Initial formation pressure is preliminary determined, oil-water contact – OWC, drilling is carried out in two rows of production wells arranged in parallel and symmetrically between rows of injection wells, at that, the distance between the injection wells in the rows and from the nearest row of production wells is kept 200 m, the distance between the production wells in rows is 150 m, production wells are made with two horizontal shafts located in one plane at the same level, with an angle between shafts of 40-50°, with length of horizontal shafts of 500-550 m, wherein the first horizontal shaft of the production well is located above the bottom of formation at 3 m or above OWC by 5 m and at an angle along the vertical of not more than 15°, the second shaft is below the formation roof by 2 m and at an angle along the vertical of not more than 10°, injection wells are made with a horizontal shaft length of 450-500 m, then five water-swellable packers are installed in each production well shaft at distance of 50 to 100 m relative to each other, starting from the "tip" of the shaft, then in all production and injection wells multi-stage hydraulic fracturing of oil formation is performed, working agent is pumped into injection wells in constant mode at pressure of 13 MPa, higher than fracture closure pressure, with constant monitoring of formation pressure, at change of formation pressure from initial by 0.5 MPa on geomechanical and hydrodynamic simulators the cyclic mode of pumping is determined, then the cyclic mode of pumping to injection wells of working agent is corrected. Application of this method will increase oil recovery of low-permeability deposit due to maximum coverage of deposit by drainage in area and section, uniform oil displacement from oil-saturated formation, high rate of oil extraction and increase of well productivity.

EFFECT: increased oil recovery of low-permeability deposit due to maximum drainage coverage of the deposit in the area and section, uniform displacement of oil from the oil-saturated formation, high rate of oil extraction and increase in well productivity.

1 cl, 1 dwg