Geologic units in Anson county, North Carolina

Newark Supergroup, Chatham Group; Chatham Group, Undivided (Triassic) at surface, covers 40 % of this area

Conglomerate, fanglomerate, sandstone, and mudstone. Conglomerate and fanglomerate shown by pattern.

Cid Formation; Metamudstone and Meta-Argillite (Cambrian/Late Proterozoic) at surface, covers 12 % of this area

(Southwest of Asheboro) Thin to thick bedded; bedding plane and axial-planar cleavage common; interbedded with metasandstone, metaconglomerate, and metavolcanic rock.

Granitic Rock (Permian/Pennsylvanian) at surface, covers 11 % of this area

Megacrystic to equigranular. Lilesville granite.

Floyd Church Formation; Metamudstone and Meta-Argillite (Cambrian/Late Proterozoic) at surface, covers 10 % of this area

(Southwest of Asheboro) Thin to thick bedded; bedding plane and axial-planar cleavage common; interbedded with metasandstone, metaconglomerate, and metavolcanic rock.

Metamudstone and Meta-Argillite (Cambrian/Late Proterozoic) at surface, covers 9 % of this area

Thin to thick bedded; bedding plane and axial-planar cleavage common; interbedded with metasandstone, metaconglomerate, and metavolcanic rock.

Middendorf Formation (Cretaceous) at surface, covers 9 % of this area

Sand, sandstone, and mudstone, gray to pale gray with an orange cast, mottled; clay balls and iron-cemented concretions common, beds laterally discontinuous, cross-bedding common.

Biotite Gneiss and Schist (Cambrian/Late Proterozoic) at surface, covers 3 % of this area

(Located in the Lilesville granite aureole) inequigranular, locally abundant potassic feldspar and garnet; interlayered and gradational with calc-silicate rock, sillimanite-mica schist, mica schist, and amphibolite. Contains small masses of granitic rock.

Terrace Deposits and Upland Sediment (Tertiary) at surface, covers 2 % of this area

Gravel, clayey sand, and sand, minor iron-oxide cemented sandstone.

Phyllite and Schist (Cambrian/Late Proterozoic) at surface, covers 2 % of this area

Locally laminated and pyritic; includes phyllonite, sheared fine-grained metasediment, and metavolcanic rock. In Lilesville granite aureole, includes hornfels.

Cid Formation; Felsic Metavolcanic Rock (Cambrian/Late Proterozoic) at surface, covers 0.6 % of this area

(Southwest of Asheboro) Metamorphosed dacitic to rhyolitic flows and tuffs, light gray to greenish gray; interbedded with mafic and intermediate metavolcanic rock, meta-argillite, and metamudstone.

Tillery Formation; Metamudstone and Meta-Argillite (Cambrian/Late Proterozoic) at surface, covers 0.1 % of this area

(Southwest of Asheboro) Thin to thick bedded; bedding plane and axial-planar cleavage common; interbedded with metasandstone, metaconglomerate, and metavolcanic rock.

Pee Dee Gabbro (Pennsylvanian) at surface, covers < 0.1 % of this area

Dark gray to black, medium to fine grained, massive.

Chatham Group, undivided (Triassic) at surface, covers < 0.1 % of this area

Conglomerate, sandstone and mudstone

Persimmon Fork Formation (Cambrian to Neoproterozoic) at surface, covers < 0.1 % of this area

Predominately metatuff

Cid Formation, Mudstone Member (Ordovician to Late Cambrian) at surface, covers < 0.1 % of this area

Thin bedded tuffaceous metasiltstone