In September 2006, the Division of Geological Survey achieved a major milestone by completing a 25-year program of remapping the bedrock geology of the state of Ohio. Beginning in 1990, the division sought to replace the 1920 bedrock geology map of the state. The Geologic Mapping Group produced the new map from 788 7.5-minute bedrock geologic quadrangles—an approach which distinguishes Ohio as one of only a few states to have complete bedrock map coverage at this scale. A more thorough discussion of mapping history and methods is included in the spring 1997 issue of Ohio Geology.
The resulting Bedrock Geologic Map of Ohio (Map BG-1) is a 1:500,000-scale, wall-size map, featuring a mosaic of colors, a correlation chart and descriptions of map units, and a detailed cross section that traces along a line from the Ohio River in Washington County to Bellefontaine to Williams County in the northwest corner of the state. As a testament to the hard work and quality put into Map BG-1, the division was honored by the Association of Earth Science Editors with a 2008 Outstanding Publication Award. Recently, the Bedrock Geologic Map of Ohio was made available in a page-size version and as a CD-ROM.
Provided below are links to further information on the Bedrock Geologic Map of Ohio and other bedrock geology products, including free downloads. For more specific questions about Ohio's bedrock geology, contact a staff geologist using our staff directory.
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