| Late Wisconsin glaciotectonic deformation structures are visible in a 1.5km long section of cliff face along the eastern shore of Lake Michigan south of Ludington, Michigan. Several apparent clay diapirs rise from below beach level to near the top of the ∼50m high cliff. The sediments exposed in the cliff face in order from oldest to youngest are a lower diamict, a lower stratified sand, an upper diamict, an upper stratified sand, and finally an eolian sand cap. The lower stratified sand is characterized by laminated clay and silt which was mobilized and deformed by glaciotectonic processes, and for the deformation structures.;Springs and gullies on the surface indicate a preferred pattern of groundwater drainage and past landslides. This project has concluded that at least one of these deformation structures is a continuous feature that does trend toward the northeast. Such information is vital in order to determine ice flow direction and preferred drainage patterns. Little is known about the local stratigraphy near the deformation structures, as the public borehole information is sparse. This study characterizes the inland extent of these deformation structures using geophysical methods, and improves understanding of the glacial history of the Ludington Ridge, specifically the related glaciotectonic processes. |
