Changes in stratigraphic sections indicate a pulse- like transition of wet/dry seasonality related to glaciation. Climatic effects of Paleogene glaciation are mirrored by an up section sequence of drying in the Brule Formation, White River Group. Coarse sediments of the Brule are replaced by loessic deposits. Climate change initiates faunal change with transition of large pulmonate gastropods to small pupoid gastropods, divergence of Oligopherus and Stylemys from Hadrianus. Global events are reflect the isotopic oxygen and carbon in fossil tortoise bone formation. Analyses of fossil materials can be applied to high resolution nonmarine stratigraphic correlation. Climatic change which ushers faunal and floral transition in the Paleogene such as: turtles to tortoises, browsing to grazing ungulates with links to Milankovitch cycles.