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Figure 4. Well log cross section showing gamma ray logs and cored intervals (red boxes) in selected wells. Gamma logs are colored yellow when API count is <65, indicating sandstone. General stratigraphic characteristics are listed for each major interval. Interval names are not formalized in the field – this represents Shell’s internal nomenclature. The definition of the “Unnamed Formation” is generally consistent with Law and Spencer (1989). Line of section is shown in Figure 1B. Well names from left to right are: Mesa 12-28D, Riverside 12c-3D, Jensen 6-11D, Jensen 11-11D, Wagon Wheel 1, Warbonnet 16d-10D, and Antelope 3-9.