METHOD FOR SUBSEQUENT FLOODING OF STRATIFIED RESERVOIR Russian patent published in 2016 - IPC E21B43/20 

FIELD: oil and gas industry.

SUBSTANCE: invention can be used in developing laminar oil formations with high degree of development. Method includes development of deposit with production and injection wells, extraction of product from production wells and pumping working agent into injection wells, processing collector with oil displacing compositions through production wells, starting operation of wells after pumping oil displacing compositions. Laboratory core studies are used to determine residual oil content of each layer-interlayer at replacement of water used for reservoir flooding. After development of reservoir by flooding and excess water cut of production well by more than 90 % geophysical survey is performed. Said studies are used to determine current oil content of interlayers. At specified condition of residual oil saturation is pumped oil ring from said formation. Said oil rin is flushed with water with lower mineralisation than mineralisation of pumped water. During pumping oil rest of interlayers are isolated by packers. Nearest injection wells are stopped. Ratio of volume of pumped oil to volume of flushed water in each interlayer is set from 1:10 to 1:100. Volume of pumped oil ring is calculated as per analytical expression considering distance from producer, in which is pumped oil rin to nearest injection well, mean thickness interlayer and its mean porosity.

EFFECT: increasing oil recovery factor at development of oil formations with high degree of development.

1 cl, 1 dwg, 2 ex