Methods of controlling water production from hydrocarbon bearing subterranean formations using dense carbon dioxide compositions

Abstract

A method for reducing water production from a hydrocarbon bearing subterranean formation includes identifying a high permeability zone in the formation and injecting a dense COcomposition from a production well into the high permeability zone. The dense COcomposition includes dense COand a thickener soluble in the dense CO. The thickener includes a copolymer that is the polymerized reaction product of monomers that include at least one alkenyl ether or dialkenyl ether monomer, at least one acrylate or methacrylate monomer, at least one structural monomer, and at least one allyl ester monomer. After injecting the dense COcomposition into the high permeability zone, the method includes withdrawing hydrocarbons from the hydrocarbon bearing subterranean formation through the production well. The dense COcomposition blocks pores in the high permeability zone to reduce or prevent flow of water from the high permeability zone into the production well.