Geologists, geotechnical consultants, land-use planners, ground water specialists, educators, and others interested in geotechnology will find many uses for Map BG-3. Map BG-3 is available in either a full-color, wall-sized version (scale 1:500,000) or on CD-ROM in geographic information system (GIS) format and is the result of a seven-year effort by the ODNR Division of Geological Survey to map the bedrock geology of the entire state of Ohio.
Ice-age glaciers advancing into western and northern Ohio smoothed and buried an ancient, complex surface that was significantly different from today's landscape. Erosion before, during, and after the glacial period created a bedrock surface that ranges from smooth to gorge-like. That bedrock surface, which is depicted on Map BG-3, is buried beneath glacial deposits commonly 25 to 50 feet thick but sometimes attaining a thickness of more than 700 feet in portions of western Ohio. One of the most striking features on the map is the remnant of the Teays River Valley, formed by a major north-flowing surface stream in southern and western Ohio prior to and throughout the time of the great glaciers. The now-buried Teays River Valley is clearly visible on the map, running between Scioto and Mercer counties. The main Teays River, and what were once its tributary streams, formed steep-walled gorges that range up to 400 feet deep and cut across buried southern and western Ohio bedrock.
Wall-size paper map: $18.50
CD-ROM of map and supporting GIS files: $25.00
Includes BG-4 series for complete state bedrock coverage.
Download the paged-size PDF version of this map [4.73 MB PDF]