K.S. Rose, Exxon Co.
The brine external polymulsion acid fracturing technique has been successfully utilized by Exxon to stimulate the low permeability carbonate reservoirs of the Permian Basin. Compared to the traditional proppant fracturing methods, this approach offers the advantages of lower cost, reduced mechanical risk, and greater adaptability to difficult well situations. Polymulsion is an external aqueous-phase oil-water emulsion. The non-Newtonian properties of this emulsion create an efficient fracturing fluid which exhibits excellent pumping characteristics. The brine external polymulsion acid fracturing technique involves pumping a pad of polymulsion fluid followed by an approximately equal volume of high viscosity acid containing a fluid loss control additive. Results obtained from the application of this technique in the Drinkard formation of the B-D-T field in Eastern New Mexico and in the Clearfork- Glorieta formations of the Robertson Clearfork Unit in West Texas will be presented.