Methods for sealing high-permeability zones in subterranean formations

Abstract

Methods for sealing high-permeability zones in subterranean formations are disclosed. The methods involve introducing a treatment fluid comprising polyacrylamide, acid, and water into a subterranean formation containing high- and low-permeability zones. The treatment fluid preferentially enters high-permeability zones, where polyacrylamide remains inactive in acidic conditions but swells upon neutralization, thereby at least partially sealing these zones. This sealing diverts subsequent fluid flow into low-permeability zones, enhancing hydrocarbon recovery. In formations with water-producing zones, the polyacrylamide selectively absorbs water, reducing unwanted water production. The treatment fluid may also include additives such as corrosion inhibitors, intensifiers, iron stabilizers, and chelants to improve operational performance. The disclosed methods provide controlled zonal coverage and improved stimulation efficiency in carbonate reservoirs.

Dependencies are inferred from the claim text.