METHOD OF WATER INFLUX SHUTOFF AND REGULATION OF FORMATION PERMEABILITY Russian patent published in 2001 - IPC

FIELD: oil producing industry, particularly, methods of shutoff of water inflows to oil producing wells and regulation of formation permeability. SUBSTANCE: method includes successive injection into well of fresh water buffer, the first and second working fluids, fresh water buffer and forcing them into formation by water. Then water injection into well is discontinued for time required for setting of gelling composition (gel formation) and well is placed into operation at low flow rate for time required for gel strengthening, and then changing over to usual operating conditions of well. The second working fluid is gelling composition unstable in pressure of mineralized waters. The first working fluid is produced by diluting with fresh water of the second working fluid. EFFECT: higher efficiency of oil recovery from nonuniform reservoirs of deposits with mineralized waters, reduced water cutting of well production and unproductive water injection, improved environmental control. 3 cl, 2 ex