METHOD FOR DEVELOPMENT OF OIL DEPOSIT IN CARBONATE RESERVOIRS Russian patent published in 2016 - IPC E21B43/22 C09K8/584 

FIELD: oil and gas industry.

SUBSTANCE: proposed method relates to oil industry, in particular to development of oil deposit in carbonate reservoirs without water-oil zones. Method for development of oil deposit in carbonate reservoirs, which involves construction of horizontal production and injection wells parallel to each other, arrangement of horizontal producing wells in lower part of productive formation, arrangement of injection horizontal wells in roof part of productive formation between production horizontal wells in horizontal projection, pumping displacement agent through injection wells and product extraction through production wells, before construction of wells, selecting section of deposit, which provides hydrodynamic connection between adjacent horizontal injection and production wells on entire thickness, during construction, selecting distance between adjacent horizontal shafts of producers and injectors directly proportional to permeability of rocks of section, wherein displacement agent is water with mineral content of not more than 4 g/l, which is pumped into productive formation with pressure higher than initial reservoir pressure of not more than 7 % of initial reservoir pressure, water pumping is stopped after reduction of intake capacity of horizontal injection wells to level, where low-mineralised water pumped into formation volume is higher than that of extracted formation fluid, then displacement agent used is 0.03-0.5 % aqueous solution of cellulose ester and 0.01-0.5 % aqueous solution of surfactant increasing in volume ratio of 1:1 to 1:5, and total volume of 30-50 % of initial oil content in formation, at pressure of pumping said aqueous solutions, 10-15 % higher than initial formation pressure, to recovery of initial reservoir pressure, after which cycles of injecting water with mineral content of not more than 4 g/l and aqueous solutions of polymers and surfactants is repeated.

EFFECT: high efficiency of processing.

1 cl, 1 ex, 2 dwg