Subterranean formation treatment fluids and methods of using such fluids

Abstract

One embodiment of the present invention provides a treatment fluid comprising water, a crosslinking agent, and a substantially fully hydrated depolymerized polymer having a C* of at least about 0.27. Another embodiment of the present invention provides a method of treating a portion of a subterranean formation comprising preparing a treatment fluid comprising water, a crosslinking agent, and a substantially fully hydrated depolymerized polymer having a C* of at least about 0.27; and, contacting the portion of the subterranean formation with the treatment fluid. Another embodiment of the present invention provides a method of fracturing a subterranean formation comprising preparing a treatment fluid comprising water, a crosslinking agent, and a substantially fully hydrated depolymerized polymer having a C* of at least about 0.27; and, placing the treatment fluid into the subterranean formation at a pressure sufficient to create or extend at least one fracture therein.

1 . A treatment fluid comprising water, a crosslinking agent, and a substantially fully hydrated depolymerized polymer having a C* of at least about 0.27.  
     
     
         2 . The treatment fluid of  claim 1  wherein the substantially fully hydrated depolymerized polymer has a molecular weight in the range of from about 50,000 to about 400,000.  
     
     
         3 . The treatment fluid of  claim 1  wherein said substantially fully hydrated depolymerized polymer comprises a guar derivative selected from the group consisting of hydroxypropylguar, carboxymethylhydroxypropylguar, carboxymethylguar, hydroxyethyl cellulose, grafted hydroxyethyl cellulose, carboxymethyl cellulose and carboxymethylhydroxyethyl cellulose.  
     
     
         4 . The treatment fluid of  claim 1  wherein said substantially fully hydrated depolymerized polymer is present in said treating fluid in an amount in the range of from about 0.2% to about 5% by weight of said water therein.  
     
     
         5 . The treatment fluid of  claim 1  wherein said crosslinking agent is selected from the group consisting of boron compounds, compounds that supply zirconium IV ions, compounds that supply titanium IV ions, aluminum compounds and compounds that supply antimony ions and wherein said crosslinking agent is present in said treating fluid in an amount in the range of from about 50 ppm to about 5000 ppm.  
     
     
         6 . The treatment fluid of  claim 1  wherein said treating fluid further comprises a pH adjusting compound for elevating the pH of the treating fluid selected from the group consisting of sodium hydroxide, potassium hydroxide and lithium hydroxide and wherein said pH adjusting compound is present in said treating fluid in an amount in the range of from about 0.01% to about 0.3% by weight of said water therein.  
     
     
         7 . The treatment fluid of  claim 1  wherein said treating fluid further comprises a buffer selected from the group consisting of sodium carbonate, potassium carbonate, sodium bicarbonate, potassium bicarbonate, sodium diacetate, potassium diacetate, sodium phosphate, potassium phosphate, sodium dihydrogen phosphate and potassium dihydrogen phosphate and wherein said buffer is present in said treating fluid in an amount in the range of from about 0% to about 0.3% by weight of said water therein.  
     
     
         8 . The treatment fluid of  claim 1  wherein said treating fluid further comprises particulates.  
     
     
         9 . The treatment fluid of  claim 1  wherein said treating fluid further comprises a foaming agent comprising at least one of the following: nitrogen, air, or carbon dioxide.  
     
     
         10 . A method of treating a portion of a subterranean formation comprising: 
 preparing a treatment fluid comprising water, a crosslinking agent, and a substantially fully hydrated depolymerized polymer having a C* of at least about 0.27; and,    contacting the portion of the subterranean formation with the treatment fluid.    
     
     
         11 . The method of  claim 10  wherein the substantially fully hydrated depolymerized polymer has a molecular weight in the range of from about 50,000 to about 400,000.  
     
     
         12 . The method of  claim 10  wherein said substantially fully hydrated depolymerized polymer comprises a guar derivative selected from the group consisting of hydroxypropylguar, carboxymethylhydroxypropylguar, carboxymethylguar, hydroxyethyl cellulose, grafted hydroxyethyl cellulose, carboxymethyl cellulose and carboxymethylhydroxyethyl cellulose and wherein said substantially fully hydrated depolymerized polymer is present in said treating fluid in an amount in the range of from about 0.2% to about 5% by weight of said water therein.  
     
     
         13 . The method of  claim 10  wherein said crosslinking agent is selected from the group consisting of boron compounds, compounds that supply zirconium IV ions, compounds that supply titanium IV ions, aluminum compounds and compounds that supply antimony ions and wherein said crosslinking agent is present in said treating fluid in an amount in the range of from about 50 ppm to about 5000 ppm.  
     
     
         14 . The method of  claim 10  wherein said treating fluid further comprises at least one of the following: particulates and a foaming agent.  
     
     
         15 . A method of fracturing a portion of a subterranean formation comprising: 
 preparing a treatment fluid comprising water, a crosslinking agent, and a substantially fully hydrated depolymerized polymer having a C* of at least about 0.27; and,    placing the treatment fluid into the portion of the subterranean formation at a pressure sufficient to create or extend at least one fracture therein.    
     
     
         16 . The method of  claim 15  wherein the substantially fully hydrated depolymerized polymer has a molecular weight in the range of from about 50,000 to about 400,000.  
     
     
         17 . The method of  claim 15  wherein said substantially fully hydrated depolymerized polymer comprises a guar derivative selected from the group consisting of hydroxypropylguar, carboxymethylhydroxypropylguar, carboxymethylguar, hydroxyethyl cellulose, grafted hydroxyethyl cellulose, carboxymethyl cellulose and carboxymethylhydroxyethyl cellulose and wherein said substantially fully hydrated depolymerized polymer is present in said treating fluid in an amount in the range of from about 0.2% to about 5% by weight of said water therein.  
     
     
         18 . The method of  claim 15  wherein said crosslinking agent is selected from the group consisting of boron compounds, compounds that supply zirconium IV ions, compounds that supply titanium IV ions, aluminum compounds and compounds that supply antimony ions and wherein said crosslinking agent is present in said treating fluid in an amount in the range of from about 50 ppm to about 5000 ppm.  
     
     
         19 . The method of  claim 15  wherein said treating fluid further comprises at least one of the following: particulates and a foaming agent.