Abstract

The Mills Ranch Complex is fast developing into one of the largest fields in the deep Anadarko basin. This complex is part of a deep, buried granite uplift which extends northwest-southeast for fifteen miles or more from Wheeler County, Texas, into Beckham County, Oklahoma. It is a long, narrow anticlinal feature paralleling a northwest-southeast striking thrust fault and is complicated by numerous faults and unconformities. The discovery well of the deep Mills Ranch-Hunton play, which started a large drilling program, was the Freeport Oil Co. No. 1 Sidney Fabian which was drilled in 1972 to a depth of 21,640 feet and completed at a calculated open flow rate of 93,050 MCF per day. Since that time a continuous program, chiefly by the Chevron-Freeport group, has proven at least three separate productive reservoirs in the Hunton. The Hunton section averages 929 feet in thickness and produces from both the Chimney Hill and the Henryhouse sections. Wells in the Hunton on the main structure are capable of producing up to 20,000 MCF per day.

The deepest commercial production in the world was found from the Arbuckle at 22,918 to 23,938 feet in the Chevron et al No. 1 James which was completed in August 1976. An offset well, the Chevron et al No. 1 Ledbetter, has been drilled to 26,550 feet in the Arbuckle formation. Deeper production on the Mills Ranch Complex could cause increased deep drilling activity in fields presently producing from only the Hunton as well as on presently non-producing structures in this part of the Anadarko basin.