The Yates field, discovered in October 1926, is extraordinary in amount of oil produced, size of original oil accumulation, and well productivity. During the 41 years since discovery, it has produced more than 500 million bbl of oil. Material balance calculations, based on past performance of the Yates field reservoir, indicate an oil-in-place of between 3.7 and 4.3 billion bbl. It has been estimated that ultimate recovery from the reservoir will be between 1.5 and 2 billion bbl. The Yates field reservoir, mostly dolomite, may be the largest single oil accumulation ever found in a North American carbonate. It occurs as a gentle dome with structural closure in excess of 350 ft and covers an area of about 21,700 acres. The principal marker in the reservoir is found at depth ranging from approximately 1,000 ft to about 1,900 ft. Nearly a third of the 637 wells potentialed for more than 10,000 bbl of oil per day, and 26 potentialed for volumes ranging from 80,000 to 205,000 bbl per day. Cavernous and high matrix porosity in the reservoir contributes significantly to the remarkable productivity of some wells in the field. The cavernous porosity probably is related to subaerial erosion.

Both the Yates field reservoir and its seal are of middle Permian age. The reservoir is largely marine bioclastic dolomite equivalent to the San Andres-Grayburg. It also includes sandstone approximately equivalent to the Queen, between the Grayburg and Seven Rivers anhydrite, the latter forming the reservoir seal.

The huge Yates field reservoir oil accumulation probably resulted from favorable location relative to coarse beds and regional migration routes. The trap, a local and regional structural high, adjoins basinal strata on two sides and is situated at the southern tip of the northward-tilted Central Basin platform.

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