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Fluvial And Sequence Stratigraphy Analysis Of The Hell Creek And Fort Union Formations To Test Models For Sedimentation Across The Cretaceous-Paleogene Boundary In Makoshika State Park, Glendive, Montana, Quintin Bendixen

Theses and Dissertations

The Cretaceous-Paleogene Boundary outcrops extensively throughout Makoshika State Park in Glendive, Montana. A distinct change in sedimentation style occurs across the Cretaceous- Paleogene in the Williston Basin deposits found in eastern Montana and western North Dakota. The well documented Hell Creek Formation of the Upper Cretaceous period consists of fresh and brackish water influenced deposits on the western low-lying coast of the Western Interior Seaway. The overlying Fort Union Formation consists of coals and fluvial sandstone deposits. Geologic explanations for the depositional shift include tectonic forces of the Sevier/Laramide Orogeny to the west, The Cretaceous-Paleogene Extinction Event, and the advancement …