Waterflood Operations in the North Meadow Creek Sussex Sand Unit

Basic reservoir data, geological data, and production history are given and a progress report presented on the North Meadow Creek Sussex Sand Unit water flood operation. Water flood equipment, water supply, water treatment for bacterial control, and operating problems peculiar to Wyoming and the Rocky Mountain area are described. The five operating companies unitized interests for the purpose of water flooding early in the primary life of the reservoir. In Dec., 1953, after four years of primary life, water was initially injected. Four producing wells were converted to input, forming a 40-acre pilot five-spot. Injection well performance in the pilot area has shown the Sussex sand to have adequate receptivity to fresh water at moderate pressure. Injected volumes required for fill-up confirm estimates on water flood efficiency and indicate waterflood recovery will exceed primary. The pilot was expanded in 1955 to encompass 80 percent of the reservoir productive acreage. Producing wells were converted to input on pattern except where faulting dictated otherwise. Introduction This paper is a report on a waterflood operation in the North Meadow Creek field, Johnson County, Wyo. The field, discovered in Dec., 1949, is located in the Powder River Basin near Linch, Wyo., 8 miles northeast of the famous Salt Creek field. Water is being injected into the Sussex sand reservoir at a depth of 4,000 ft. Before commencing the pilot injection test, the five working interest owners in the field unitized the Sussex sand reservoir with unit participation being divided among Delhi-Taylor Oil Corp., Continental Oil Co., American Liberty Oil Co., Mimi Corp., and Murchison Trust. Although the operation is normal in most respects, it is the only full scale pattern water flood in the Rocky Mountain area. It is also of special interest to note that the operators recognized the adaptability of the Sussex sand to water flooding and unitized for this purpose early in the primary life. It shall be the purpose of this paper to present basic reservoir and geological characteristics of the Sussex reservoir as well as to discuss operating practices, water supply, flood equipment, and pilot waterflood performance.