THE ALABAMA GRAPHITE-V BELT: PRELIMINARY RESULTS FROM THE GEOLOGICAL SURVEY OF ALABAMA IN PARTNERSHIP WITH THE USGS’S EARTH MAPPING RESOURCES INITIATIVE

Graphite and vanadium (V), two critical minerals recognized by multiple U.S. government agencies, including the U.S. Geological Survey, are respectively used in lubricants, batteries, and fuel cells and as a strengthener, hardener, and anti-corrosive in steel and iron alloys. The Alabama graphite-V belt covers an area of c. 1,130 km² in the eastern Blue Ridge terrane of the northern Piedmont province and includes the graphite- and vanadium-bearing lithologies of the Poe Bridge Mountain, Higgins Ferry, and Hatchet Creek Groups. This area of the State produced graphite from the late 1800s to the 1950s and potentially has the largest flake graphite deposits in the conterminous United States. Due to the historical record of graphite mining and renewed interest in this area by the mineral exploration industry, the Geological Survey of Alabama, in partnership with the U.S. Geological Survey Earth Mapping Resources Initiative (EMRI), recently began a 2-year mapping and geochemical sampling project focusing on two 7.5-minute quadrangles in the southwesternmost extent of the graphite-V belt (Mitchell Dam and Flag Mountain). The Higgins Ferry Group, which was metamorphosed at mid- to upper-amphibolite facies conditions, is the principal graphite- and V-bearing unit within this part of the EMRI focus area.

Geologic mapping of the two quadrangles is underway and will be complimented by USGS-planned magnetic, radiometric, and resistivity data acquisition. Most of the graphite occurs as <1 to 3 mm flakes in schist, gneiss, and quartzite and modal abundance varies from c. 1% to 15%, and locally, higher. Graphite also occurs as centimeter-scale veins in quartz and is associated with large 1-10 cm long kyanite blades. Green V-bearing mica (in other words, roscoelite) occurs in combination with the flake graphite and coarsens in proximity to quartz veins and pegmatites. These graphite and roscoelite lithologies form long, erosionally resistant northeast-southwest trending linear ridges in the area. Samples of these lithologies were submitted for geochemical analyses and the graphite crystallinity is being evaluated by Raman analyses. Here, we present preliminary mapping and sampling results from the various Higgins Ferry Group graphite-V lithologies in the Alabama graphite-V belt on the Mitchell Dam and Flag Mountain quadrangles.