THREE-DIMENSIONAL SURFICIAL GEOLOGY OF THE CLEVELAND SOUTH 30X60-MINUTE QUADRANGLE

The Geologic Mapping Group of the Division of Geological Survey (DGS) recently completed mapping of the surficial geology in the Cleveland South 30x60-minute quadrangle (1:100,000 scale). Work maps were prepared for the area’s 32 1:24,000-scale quadrangles that show surficial lithologies and their thicknesses in vertical sequences, from the surface down to bedrock. Data analyzed during mapping included existing glacial maps, reports, and theses; county soil surveys; highway, engineering, and environmental boring records; and water-well logs. These maps were then compiled into a 1:100,000-scale final map in a GIS environment, and represents the DGS’s first digitally prepared surficial product. Map colors indicate the uppermost lithology and shading indicates topographic relief. Many areas on the map require modification of previous interpretations of the area’s glacial geology. The thickness of glacial deposits ranges from zero to over 500 feet. The extent of interlobate ice-contact deposits and of thick lacustrine deposits in major valleys is greater than previously mapped. The numerous large areas of thinly mantled or exposed bedrock have not been previously depicted. Several drainage reversals, such as the capture of the upper Cuyahoga River basin at Cuyahoga Falls, are readily apparent. This project was partially funded by the U.S. Geological Survey, National Cooperative Geologic Mapping Program, STATEMAP component.