Patent ID: 9399728
Filing Date: 2016-07-26
CPC Classification: C09K

Claim Text:
1. A method of treating a zone of a subterranean formation penetrated by a wellbore, the method comprising the steps of: (a) forming a treatment fluid comprising: (b) introducing the treatment fluid through the wellbore into the zone; (c) allowing the strong acid in the treatment fluid to spend in the formation; (d) allowing the pH of the fluid to increase to a range of from about 1 to about 3 for the aluminum to crosslink the polymer, thereby forming a crosslinked gel in the zone; and (e) allowing time for the strong acid and any other acids in the previously-introduced treatment fluid to continue to spend against the formation such that the pH of the crosslinked gel formed in the zone increases sufficiently to break the crosslinked gel, thereby reducing the viscosity of the crosslinked gel in the zone.