Dry Creek field produces oil from thin Lansing (Pennsylvanian) limestone beds at a depth of about 4,000 ft (1,200 m) in central Hitchcock County, Nebraska. This subtle oil accumulation was discovered in 1963 by good fortune and weakly quantified subsurface geology; it remains geologically ill-defined. Conventional subsurface studies have been of little value in explaining the oil accumulation at Dry Creek field.

We have developed a method for evaluating thin Lansing reservoir beds that incorporates careful analysis of cuttings and logs of early vintage. This method facilitates mapping Lansing reservoir distribution, thereby permitting a better understanding of the subtle trap at Dry Creek. We believe this method can be used as an additional subsurface exploration tool in the northern Mid-Continent.

Subsequent to original publication of the methods described in this study, additional wells have been drilled at Dry Creek field. Some of these wells supported our original interpretation of reservoir distribution at Dry Creek, while others did not. Recently, the geologic techniques developed at Dry Creek field have been used successfully in exploration drilling in Decatur County, Kansas.

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