Grandfather Mountain Formation; Porphyritic felsic volcanic rock

Phyllitic to schistose, contains euhedral to subhedral phenocrysts of gray quartz and pink potassic feldspar. Resembles quartzite and meta-arkose.
State North Carolina
Name Grandfather Mountain Formation; Porphyritic felsic volcanic rock
Geologic age Late Proterozoic
Lithologic constituents
Major
Metamorphic > Metaigneous > MetavolcanicPorphyritic felsic volcanic rock - phyllitic to schistose, contains euhedral to subhedral phenocrysts of gray quartz and pink potassic feldspar. Resembles quartzite and meta-arkose.
References

Rhodes, Thomas S., and Conrad, Stephen G., 1985, Geologic Map of North Carolina: Department of Natural Resources and Community Development, Division of Land Resources, and the NC Geological Survey, compiled by Brown, Philip M., et al, and Parker, John M. III, and in association with the State Geologic Map Advisory Committee, scale 1:500,000.

The North Carolina Dept. of Environment, Health, and Natural Resources, Division of Land Resources, NC Geological Survey, in cooperation with the NC Center for Geographic Information and Analysis, 1998 (updated 2007), Geology - North Carolina (1:250,000), coverage data file geol250. The data represents the digital equivalent of the official State Geology map (1:500,000 scale), but was digitized from (1:250,000 scale) base maps.

NGMDB product
Counties Burke - Caldwell - Watauga