Recent drilling in the Absaroka plate of the Wyoming thrust belt has confirmed the presence of a major gas-condensate accumulation in the Whitney Canyon area of Uinta County, Wyoming. Reserves are primarily in porous and/or fractured Paleozoic carbonate formations. Triassic carbonate rocks also appear to be commercially productive.

The discovery well, which was scheduled as a 13,400-ft (4,084 m) test, was spudded in October 1976. Mechanical problems were encountered at 10,691 ft (3,259 m) in the Permian Phosphoria Formation and the well was subsequently completed in the Triassic Thaynes Formation. Paleozoic gas production was established in 1978 by the Amoco-Chevron-Gulf No. 2 well, which was drilled into a nearly normal stratigraphic section of Jurassic Twin Creek Limestone through Ordovician Bighorn Dolomite before crossing the Absaroka thrust at a true vertical depth (TVD) of 15,516 ft (4,729 m). Cretaceous sandstones and shales were drilled to a total depth of 16,224 ft (4,945 m) or 15,894 ft (4,845 m) TVD. A development well located approximately one mile north of the No. 2 well was drilled into a similar s ratigraphic sequence.

The Whitney Canyon structure is a north-trending geophysical anomaly with little or no surface expression. Its general shape can be defined well with reflection seismic data. At the Phosphoria level, the structure is approximately 10 mi (16 km) long and 2 mi (3.2 km) wide with 2,500 ft (762 m) of closure.

Gas tested to date from the Triassic Thaynes Formation is sweet, whereas the Paleozoic gas is sour with a maximum H₂S content of 18%. Environmental considerations and gas treatment plant construction will delay Paleozoic gas production until late 1981.

Although reserve estimates for the Whitney Canyon structure are quite speculative at this time, it appears to be a giant field.

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