Well treatment method using fluid containing lactic acid or salt thereof

A method of fracturing a subterranean carbonate formation of an oil or gas well to stimulate production of hydrocarbons, the method comprising injecting into the carbonate formation a fracturing fluid at a pressure sufficient to form fractures within the formation, the fracturing fluid comprising an aqueous acid, synthetic polymer, metal crosslinking agent and lactic acid or a lactic acid salt and a gel breaker, wherein the amount of lactic acid or lactic acid salt in the fracturing fluid is between from about 10 to about 1000 pounds per 1,000 gallons of fracturing fluid.

In a method of fracturing a subterranean formation of an oil or gas well to stimulate production of hydrocarbons by injecting at high pressure into the formation a fracturing fluid comprising an aqueous acid, a synthetic polymer and a metal crosslinking agent, the improvement comprising retarding or preventing crosslinking between the synthetic polymer and metal crosslinking agent at temperatures less than about 100° F. by inclusion of lactic acid or a lactic acid salt in the fracturing fluid, the lactic acid or lactic acid salt being present in an amount between from about 10 to about 1000 pounds per 1000 gallons of fracturing fluid.