Natural Resources, School of


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Published in Proceedings of the Nebraska Academy of Sciences including the GNATS and TER-QUA Divisions and Nine Affiliated Societies, 95th Annual Meeting, April 12–13, 1985, pp. 56–57.


Copyright © 1985, J. B. Swinehart, V. L. Souders, H. M. DeGraw, and R. F. Diffendal, Jr.


The White River Group traditionally has been divided into three stratigraphic units in western Nebraska, the Chadron, Orella, and Whitney. We also recognize three depositional sequences in the group but these consist of the following stratigraphic intervals (oldest to youngest): 1) the base of the Chadron to the unconformity in the Orella Member; 2) the unconformity to the top of the Whitney; and 3) the Brown Siltstone beds (a new informal unit). We divide the Arikaree into three units; 1) the Gering; 2) Monroe Creek-Harrison formations; and 3) the Upper Harrison beds.