EXTENDING INTERSTATE EDGE-MATCHING INTO THE NORTH CAROLINA PIEDMONT: PRODUCTION OF THE GEMS LEVEL 3 RALEIGH 100K BEDROCK GEOLOGIC MAP

The North Carolina Geological Survey completed a one-year project to convert the Raleigh 100K bedrock geologic map to GeMS Level 3 in support of the U.S. GeoFramework Initiative. Field mapping for the existing Raleigh 100K map, which was published as a paper Open-File Report in 2004, began in 1993 and ended in 2001. Since then, there have been additional STATEMAP and EDMAP mapping projects by Skip Stoddard and David Blake and their students in the adjacent Henderson 100K. This additional mapping has identified a new terrane in NC that has major implication for existing Raleigh 100K mapping.

The Raleigh 100K compilation work was undertaken to fix edge-match issues both at the 24K scale within the existing Open-File map and between the Raleigh 100K and the adjacent Henderson and Chapel Hill 100k quadrangles, as well as update map units based on the new Henderson 100K data. Since the Henderson 100K is edge-matched with geologic mapping in Virginia, the Raleigh 100K helps extend interstate edge-matching efforts into the interior of North Carolina.