The Cherokee Ridge is a complex anticlinal arch separating the Washakie basin, Wyoming, from the Sand Wash basin on the south in Colorado. Several fields, primarily gas, are located on the Cherokee Ridge. Exploration has been based primarily on structural "plays" and has proved successful. With present control, it can be demonstrated that at least part of the fields are stratigraphic with only the area and size modified by the structural configuration.

The trapping mechanisms of several fields on the eastern and western ends of Cherokee Ridge are varied and provide templates to guide further exploration.

On the eastern Cherokee Ridge, traps for gas are formed by: (a) structural closure (South Baggs and West Side Canal fields); (b) closure against the downthrown side of a fault (Four Mile Creek field); and (c) porous Lewis and Mesaverde sandstones crossing the Cherokee Ridge (South Baggs and Pole Gulch fields).

On the western end of the Cherokee Ridge, gas accumulations are formed by: (a) structural closure (most fields in some degree); (b) truncation of reservoir sandstones in Lewis and Fox Hills across structural noses (West Hiawatha and Canyon Creek fields); (c) Almond sandstones (uppermost Mesaverde) developed on and across structures (Sugar Loaf, Canyon Creek, and Pioneer fields); and (d) facies change (with possible hydrodynamic reinforcement) in the Trail and Canyon Creek zones of the Mesaverde (Trail and Canyon Creek fields).

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