Patent ID: 6273192
Filing Date: 2001-08-14
Classification: C09K,E21B

Abstract:
A method for strengthening a subterranean formation in the near wellbore area by injecting an aqueous gellable composition containing a cross-linkable polymer and a cross-linking ion into the subterranean formation through a wellbore into the near wellbore area to increase the consolidation and cementation of the subterranean formation in the near wellbore area while retaining the ability of the subterranean formation to produce fluids from outside the near wellbore area, the method consisting essentially of:a) injecting a quantity of the aqueous gellable composition sufficient to fill a pore volume of the subterranean formation around the wellbore outwardly for a distance of about three to six wellbore diameters into the subterranean formation in at least two portions;b) injecting a quantity of a non-gellable liquid into the subterranean formation between the at least two portions; and,c) retaining the aqueous gellable composition and the non-gellable liquid in the near wellbore area extending outwardly from the wellbore for the distance of from about three to six wellbore diameters until the gellable composition has gelled to strengthen the near wellbore area and create pores through the gellable composition in the near wellbore area for the production of fluids from outside the near wellbore area through the wellbore.