Patent ID: 9410415
Filing Date: 2016-08-09
CPC Classification: C09K,E21B

Claim Text:
1. A method of fracturing a subterranean formation penetrated by a wellbore, comprising the steps of: formulating a viscous fracturing fluid comprising (i) water, (ii) a hydratable polymer selected from the group consisting of guar and guar derivatives, (iii) a borate based crosslinking agent and (iv) a proppant, wherein the hydratable polymer loading in the viscous fracturing fluid is from 6 to 18 pptg; pumping the viscous fracturing fluid through an entrance site in the wellbore into the reservoir; and propagating fractures within the reservoir while decreasing the viscosity of the viscous fracturing fluid distally from the entrance site wherein at least one of the following conditions prevail at in situ conditions during propagation of the fractures: (a) the apparent viscosity of the fracturing fluid 100 feet from the entrance site is less than 10 percent of the apparent viscosity of the fracturing fluid at the entrance site; (b) the apparent viscosity of the fracturing fluid 15 minutes after introduction into the entrance site is less than 15% of the apparent viscosity of the fracturing fluid at the entrance site; or (c) the apparent viscosity of the fracturing fluid is less than 10 cP within 15 minutes after being introduced through the entrance site.