Geologic units in Macon county, North Carolina

Additional scientific data in this geographic area

Coweeta Group; Biotite Gneiss (Middle/Late Proterozoic) at surface, covers 44 % of this area

Migmatitic; interlayered and gradational with biotite-garnet gneiss and amphibolite; locally abundant quartz and alumino-silicates. Stratigraphic position uncertain.

Ashe Metamorphic Suite and Tallulah Falls Formation; Biotite gneiss (Late Proterozoic) at surface, covers 11 % of this area

Interlayered with biotite-garnet gneiss, biotite-muscovite schist, garnet-mica schist, and amphibolite.

Ashe Metamorphic Suite and Tallulah Falls Formation; Muscovite-biotite gneiss (Late Proterozoic) at surface, covers 9 % of this area

Locally sulfidic; interlayered and gradational with mica schist, minor amphibolite, and hornblende gneiss.

Ocoee Supergroup, Great Smokey Group; Metasandstone, Metagraywacke, Metasiltstone, and Mica Schist (Late Proterozoic) at surface, covers 7 % of this area

Beds and lenses of calc-silicate rock locally abundant; garnet, staurolite, and cross-biotite porphyroblasts common in fine-grained layers. Includes Hughes Gap and Hothouse formations in southern area; Horse Branch Member of Ammons Formation and Grassy Branch Formation in northern area.

Ocoee Supergroup; Great Smokey Group, undivided (Late Proterozoic) at surface, covers 5 % of this area

Thick metasedimentary sequence of massive to graded beds of metagraywacke and metasiltstone with interbedded graphitic and sulfidic slate and schist.

Coweeta Group (Late Proterozoic) at surface, covers 5 % of this area

Quartz dioritic gneiss, feldspar-quartz-biotite gneiss, metasandstone and quartzite, alumino-silicate schist, garnetiferous biotite gneiss, and minor amphibolite. Quartz dioritic gneiss predominant.

Ocoee Supergroup, Great Smokey Group; Wehutty Formation (Late Proterozoic) at surface, covers 4 % of this area

Slate to schist, dark gray, graphitic and sulfidic; includes mica schist, metagraywacke, and metaconglomerate.

Rabun Gneiss (Ordovician) at surface, covers 4 % of this area

Weakly to well foliated, granitic to quartz monzonitic.

Coweeta Group; Amphibolite (Middle/Late Proterozoic) at surface, covers 3 % of this area

Equigranular, massive to well foliated, interlayered, rarely discordant, metamorphosed intrusive to extrusive mafic rock; may include metasedimentary rock.

Quartz Diorite to Granodiorite (Devonian) at surface, covers 3 % of this area

Contains biotite, muscovite, and xenocrysts. Includes Whiteside Mountain, Stone Mountain, Mount Airy, Spruce Pine, and other smaller plutons.

Ocoee Supergroup, Great Smokey Group; Copperhill Formation (Late Proterozoic) at surface, covers 2 % of this area

Metagraywacke, massive, graded bedding common; includes dark-gray slate, mica schist, and nodular calc-silicate rock.

Ocoee Supergroup, Great Smokey Group; Dean Formation (Late Proterozoic) at surface, covers 1 % of this area

Sericite schist with cross-biotite, staurolite, and garnet porphyroblasts; interbedded metagraywacke and quartz-pebble metaconglomerate.

Biotite Granitic Gneiss (Middle Proterozoic) at surface, covers 1 % of this area

Unconformity; pinkish gray to light gray, massive to well-foliated, granitic to quartz monzonitic; includes variably mylonitized orthogneiss and paragneiss, interlayered amphibolite, calc-silicate rock, and marble. Includes granites of the Bryson City area, Straight Fork window, and Elk Park Plutonic Suite.

Ashe Metamorphic Suite and Tallulah Falls Formation; Amphibolite (Late Proterozoic) at surface, covers 0.5 % of this area

Equigranular, massive to well foliated, interlayered, rarely discordant, metamorphosed intrusive to extrusive mafic rock; may include metasedimentary rock.

Nantahala Formation and Tusquitee Quartzite, undivided (Late Proterozoic) at surface, covers 0.5 % of this area

Nantahala Formation: slate and metasiltstone, dark gray, laminated to thin bedded, sulfidic; Tusquitee Quartzite: white to light yellowish gray, numerous, thin slate layers.

Mineral Bluff Formation (Late Proterozoic) at surface, covers 0.2 % of this area

Quartz-chlorite-sericite schist and phyllite with thin quartzite layers and minor interbedded graphitic schist, garnet-mica schist, staurolite schist, cross-biotite schist, and dark slate.

Meta-ultramafic Rock (Paleozoic/Late Proterozoic) at surface, covers 0.2 % of this area

Metamorphosed dunite, local peridotite; serpentinite, soapstone, and other altered ultramafic rock. Only larger bodies shown.

Murphy Marble, Andrews Formation, and Nottely Quartzite, undivided (Late Proterozoic) at surface, covers < 0.1 % of this area

Murphy Marble: calcareous to dolomitic; Andrews Formation: calcareous cross-biotite schist; Nottely Quartzite: meta-orthoquartzite with slate.

Brasstown Formation (Late Proterozoic) at surface, covers < 0.1 % of this area

Cross-biotite schist; includes micaceous quartzite in lower part.