| description:
|
This data layer contains the bedrock-geology units that are represented as points on the 1:24,000-scale bedrock-geology maps. The points represent geologic units that are too small to represent as polygons in a GIS data set. The points were originally derived from the 1:24,000-scale bedrock-geology maps, which were created between the mid 1960's through 1997. Detailed mapping at 1:24,000 scale was performed in Ohio from the 1960's to the 1980's. During that time period, 37 7.5-minute quadrangles were mapped in detail. The bedrock-geology mapping program was initiated at the Ohio Division of Geological Survey in 1991 to perform reconnaissance geologic mapping at 1:24,000 scale. The reconnaissance and detailed geologic mapping have been combined together into this GIS dataset. There will be edge-matching issues between the reconnaissance and detailed geologic maps. |