Big Muddy Water Flood

This paper presents a summary of the production and waterflood history of the Second Wall Creek Reservoir in the Big Muddy field. This highly successful Eastern Wyoming water flood has doubled the production from the Wall Creek in less than two years of operation. An outline of the laboratory and reservoir studies which culminated in the installation of a pilot water flood in 1953 is presented. Pertinent reservoir data, such as oil and water saturations, are given. The development program and current production practices of the waterflood program are also presented. The primary and waterflood performance is shown for several individual wells and for the entire flood. Cumulative waterflood recoveries and the estimated ultimate recoveries are given, in conjunction with the current development and operating costs and the future economics of the waterflood program. Introduction The Big Muddy oil field is located about 4 miles west of Glenrock in Converse County, Wyo. The field was discovered in 1916, although Wall Creek production was not encountered until 1917, when State 10 Lease Well No. 1 was brought in flowing at a rate of 150 BOPD. This discovery touched off a prolific drilling program and brought about one of Wyoming's famous oil booms. Most of the wells drilled to the Wall Creek were located along the crest of the structure and were generally spaced on a 10-acre pattern as shown in Fig. 1. Full development of acreage did not take place on leases located on the flanks of the structure. However, lease line drilling was sufficient to prove up this peripheral area. The majority of wells were drilled with cable tools to the top of the sand. Casing was then run and the wells tailed in to a depth 50 to 60 ft below the sand top. A typical casing program consists of 40 ft of 20 in. surface pipe, 250 ft of 15 1/2 in. pipe to seal off a good water sand, 1,000 ft of 12 1/2 in. pipe to combat hole cavings and finally 3,000 ft of 6 1/4 in. casing set on top of the sand. There is little record of cementing having been done in the early wells.