Research for my Masters degree investigated the transition from flexural to dynamic subsidence in the Upper Cretaceous foreland basin in southwestern Wyoming. I spent 10 weeks during the summer of 2010 studying the Campanian-earliest Maastrichtian Ericson Formation, exposed around the Rock Springs uplift. Data collected in this study included measured sections, sedimentary architectural analysis, petrographic thin sections, and detrital zircon U-Pb dating of sandstones throughout the formation. Detrital zircon U-Pb analyses provided the first radiometric ages for this unit and demonstrated that the flexurally dominated Sevier foreland basin had transitioned to dynamic subsidence by at least 75 Ma. Detrital zircon U-Pb provenance analysis suggested that the Ericson Formation was receiving sediment eroded off of the Uinta Uplift by ~75 Ma. Results of this study are published here