Surficial geology of Pictured Rocks National Lakeshore, Michigan, USA

Abstract

ABSTRACT Pictured Rocks National Lakeshore is located in the Upper Peninsula of Michigan along the southern shore of Lake Superior. The park spans approximately 300 km2 and is almost fully incorporated within the ten 7.5-minute quadrangles presented in this new, detailed surficial geology map. The western quadrangles are mainly characterized by thin accumulations of undifferentiated Quaternary sediment above shallow bedrock while the eastern quadrangles mostly show thick accumulations of various glacial outwash units. This map was produced by integrating field data with a high-resolution LiDAR digital elevation model and associated hillshade, aerial imagery, and passive seismic data. The high-resolution elevation information was essential to differentiate between outwash units, post-glacial sand accumulations, and interpreting subtle glacial features that would have otherwise remained unrecognized. This new map provides fundamental information to help decipher the glacial history of this region to enhance our understanding of how this popular landscape developed.