Study and Application of Shallow Water Fracturing Fluid in High Temperature Deep Carbonate Reservoir

The Taklimakan is the second largest desert in the world; the TaZhong oilfield is located in the Taklimakan Desert heartland. The Ordovician carbonate is one of the producing zones of TaZhong field. Acid fracturing has been normal for stimulating wells in these carbonate formations. The freshwater prepared for fluid and acid was conveyed 300 kilometers far away from TaZhong oilfield in the early construction, a lot of money and time was spent on transportation. However, there is superficial saltwater at a depth of tens of meters under the desert, and this paper will provide the technology of reducing freshwater consumption by using shallow saltwater for pad fluid in acid-fracturing. First, this paper presents a brief developed history of TaZhong oilfield and the characteristics of Ordovician formation. In major, this paper introduces the study and case of Taklimakan desert superficial saltwater fracturing fluid, including the shallow water salinity tests and the problems of shallow water fluid, solutions for stable fluid and the performances of superficial saltwater fluid, such as the stability of saltwater fluid, rheology, and gel breaking and injures. Final, a field example of acid fracturing used shallow water fluid is included, and the responses of treating pressure are analyzed. This work has helped prove the shallow saltwater in the desert of TaZhong oilfield which is feasible for service in acid-fracturing treatment oprations, a result has been established that a reliable fracturing fluid with good performance is wide used recent years. Because of the technology of superficial water fracturing fluid, an acid fracturing treatment well time saving is 2 to 3 days, and the transportation cost saving was considerable.