Abstract

The Yates Field is located near Iraan in Pecos County, TX on the very tip of the Central Basin Platform in the Permian Basin. The discovery well, TransContinental Oil #1-A, was drilled based on Cretaceous surface mapping. The field from its discovery in 1926 has phenomenal individual well daily production rates from exceptionally shallow depths. The field produces from the Permian Seven Rivers, Queen, Grayburg and San Andres Formation. Initial drilling by late 1930 had 395 producing wells with a potential to produce 5.5 million barrels of oil per day. Early production was limited by the lack of pipeline capacity, which rose to 140,000 BOPD in 1930. These limitations led to the formation of a committee to formulate the first proration schedule to protect the interests of all operators. Marathon Oil sought to reverse declining reservoir pressure and encroachment of water on the edges of the field after 40 years of production by unitization, which was approved July 1, 1976 with Marathon as the operator. A new allowable of 100,000 BOPD replaced the old 50,000 BOPD. Facilities were capable of handling 125,000 BOPD. From unitization to the purchase of the field by KinderMorgan CO2 in late 2003, Marathon had repressurized the reservoir, used double displacement to stabilize an oil column fed by gravity drainage, experimented with pilot projects involving steam, surfactants and CO2 injection, and drilled horizontal drain holes (HDH) in the oil column. KinderMorgan immediately went to field wide CO2 injection in the gas cap to enhance gravity drainage and continued the HDH program. A total of 610 HDH wells were drilled by reentering vertical wells, cutting the casing and kicking off the HDH. Production is currently at 23,300 BOPD +352,600 MCFGD and 580,400 BWPD. Cumulative production of oil since discovery is 1.5 billion Bbl and nearly 294,733,000 MCF.