METHOD OF ISOLATING FLUSHED ZONES IN OIL FORMATION Russian patent published in 2002 - IPC

FIELD: oil-gas producing industry, particularly, methods of isolation of high-permeability water-saturated interlayers in oil formation; applicable in producing and injection wells in workover. SUBSTANCE: method includes injection into well of preventing fluid, cross-linking agent and water inflow shutoff. Preventing fluid is used in the form of mixture of oil with emultal. Cross-linking agent used in the form of solution of oil with polyacrylamide. Water inflow is shutoff by successive injection of oil-cement slurry and water-swelling polymer. After holding for allowing cement setting, excessive pressure is built-up in well. EFFECT: increased oil production and formation oil recovery due to higher quality and efficiency of water shutoff jobs. 1 tbl, 1 ex