Fracturing of the Miocene Sand in South Louisiana

Abstract

Abstract The Miocene sands of South Louisiana have not responded to fracture treatments in the past, or the results have been limited and not past, or the results have been limited and not economical. Using a two-phase gel system for efficient transport of high sand concentrations in the fracture coupled with high-pressure pumping equipment for placement at depths greater than 16,000 ft has increased the flow capacity and the recoverable reserves sufficiently to make the program economically attractive. This paper describes the design, job performance, and results of this treatment. performance, and results of this treatment Introduction The M-24 Miocene sand is the deepest producing sand in the Venice Field, producing sand in the Venice Field, Plaquemines Parish, La. It is described as Plaquemines Parish, La. It is described as fine to very fine grained, firm to hard, and sometimes silty and shaley. Over all, the sand interval is generally comprised of numerous sand members separated by distinct shale breaks. Characteristically, the M-24 sand has low porosity and permeability, especially when porosity and permeability, especially when compared with shallower Miocene sands in the same field. Venice Field is located adjacent to a large Salt dome. Fig. 1 is a map of the entire salt dome showing the position of the wells around it and those drilled through the overhanging portion of the salt. Cattle Farms A No. 3 is portion of the salt. Cattle Farms A No. 3 is almost surrounded by faults radiating from the salt dome (Fig. 2). This faulting is sufficient to limit the A No. 3 to a single-well reservoir. Secondary mineralization of salts around the dome eliminated all porosity and permeability in this area. TREATMENT AND PRODUCTION HISTORY Cattle Farms A No. 3 was completed in May 1975. Initial production through perforated interval (Fig. 3) 16,105 to 16,120 ft was 89 BOPD, 667 Mcf/D with a flowing tubing pressure of 300 psig. A bottom-hole pressure survey on May 31, 1975, indicated a flowing bottom-hole pressure of only 1,087 psig. After shut-in, pressure of only 1,087 psig. After shut-in, the pressure built to 5,487 psig in 7 hours, indicating wellbore damage or lack of permeability. permeability. Additional perforations in the 16,040- to 16,070-ft interval were added in another sand stringer to increase production.