PROCESS FOR RECOVERY OF OIL FROM AN OIL-BEARING FORMATION

摘要

The present invention is directed to a process for producing oil. The mass action ratio (MAR) of divalent cations to monovalent cations of water from an oil-bearing formation is determined, and an aqueous displacement fluid having a total dissolved solids content of from 200 ppm to 5,000 ppm and a MAR of divalent cations to monovalent cations of from 70% to 130% of the MAR of divalent cations to monovalent cations of the formation water is introduced into the formation. Oil is produced from the formation after introducing the aqueous displacement fluid into the formation.