The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 28, 1992
Filed:
May. 31, 1991
James E Tackett, Littleton, CO (US);
Marathon Oil Company, Findlay, OH (US);
Abstract
A conformance improvement treatment process is provided for reducing the permeability of a higher-permeability zone in a subterranean hydrocarbon-bearing formation which is in fluid communication with a lower-permeability zone of the formation. The process includes preparing a gel precursor solution at the surface, injecting the solution into a wellbore penetrating the formation, placing the solution in the higher-permeability zone and gelling the solution therein. In situ gelation of the solution results in substantial permeability reduction to the higher-permeability zone. A specific gel precursor solution is utilized which contains a gelling agent and a polymer formed from at least two distinct monomers wherein the first monomer has a relatively faster, yet controlled, rate of hydrolysis and the second monomer has a relatively slower rate of hydrolysis. Gelation of the solution is delayed until a substantial number of carboxylate groups are formed in situ on the polymer. The gelling agent subsequently reacts with the carboxylate groups to effect gelation of the solution.