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Stratigraphy and Geologic History of the Montana Group and Equivalent Rocks, Montana, Wyoming, and North and South Dakota

From introduction: This is a progress report on regional stratigraphic and paleontologic studies of the Upper Cretaceous Montana Group and equivalent rocks in the northern part of the western interior of the United States. It presents preliminary data on the positions of strandlines during a 14-m.y. (million year) span of the Late Cretaceous as well as our interpretations of the geologic history of this period.

Date: 1973

Creator: Gill, James R. & Cobban, William Aubrey

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Mineralogy and Stratigraphy of the Lower Part of the Pierre Shale, South Dakota and Nebraska

From abstract and introduction: Mineralogic and stratigraphic studies of the lower part of the Pierre Shale of Late Cretaceous age along the Missouri River indicate correlations different from those generally accepted. The purposes of this paper are to present evidence for the new correlations and to resolve problems of formal nomenclature that result from them.

Date: 1965

Creator: Schultz, Leonard Gene