Method of improving injectivity profiles and/or vertical conformance in heterogeneous formations

摘要

Improved injectivity profiles and/or vertical conformance in flooding heterogeneous formations containing high permeability zones is obtained by injecting an aqueous polyacrylamide solution and an aqueous formaldehyde solution into the formation and allowing the polyacrylamide to react with the formaldehyde in the relatively high permeability zones to form a gel. Thereafter, improved sweep efficiency is realized in displacing hydrocarbon from the lesser permeability zones.