Map PDF PDF of Bedrock Geologic Map, Columbia Quadrangle, Monroe and St. Clair Counties… General Information: Description 34" x 41" single map sheet, contains map, legend, descriptive stratigraphic column, and descriptive text Publication Details: Publication Date 2000 Authors Joseph A. Devera Map Details: Theme Bedrock Geology Quadrangles Columbia Scale Category Quadrangle Scale 1:24,000 GIS Data Downloads: https://chf.isgs.illinois.edu/maps/quad/columbia-bg-gems.zip
