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Mineral Resources > Online Spatial Data > Geology > by state > North Carolina Geology

Geologic units in Chatham county, North Carolina

Newark Supergroup, Chatham Group; Chatham Group, Undivided (Triassic) at surface, covers 14 % of this area

Chatham Group, Undivided - conglomerate, fanglomerate, sandstone, and mudstone. Conglomerate and fanglomerate shown by pattern.

Lithology: conglomerate; sandstone; mudstone

Phyllite and Schist (Cambrian/Late Proterozoic) at surface, covers 0.1 % of this area

Phyllite and Schist - minor biotite and pyrite; includes phyllonite, sheared fine-grained metasediment and metavolcanic rock.

Lithology: phyllite; schist; phyllonite; metasedimentary rock; metavolcanic rock

Felsic Metavolcanic Rock (Cambrian/Late Proterozoic) at surface, covers 37 % of this area

Felsic Metavolcanic Rock - metamorphosed dacitic to rhyolitic flows and tuffs, light gray to greenish gray; interbedded with mafic and intermediate metavolcanic rock, meta-argillite, and metamudstone.

Lithology: felsic metavolcanic rock; mafic metavolcanic rock; intermediate metavolcanic rock; meta-argillite; metasedimentary rock

Metamorphosed Gabbro and Diorite (Paleozoic/Late Proterozoic) at surface, covers 0.1 % of this area

Metamorphosed Gabbro and Diorite - foliated to massive.

Lithology: metamorphic rock

Metamorphosed Granitic Rock (Cambrian/Late Proterozoic) at surface, covers 8 % of this area

Metamorphosed Granitic Rock (520-650 my) - megacrystic, well foliated, locally contains hornblende; Fountain intrusive.

Lithology: metamorphic rock

Newark Supergroup, Chatham Group; Pekin Formation (Triassic) at surface, covers 6 % of this area

Pekin Formation - conglomerate, sandstone, and mudstone.

Lithology: sandstone; mudstone; conglomerate

Mafic Metavolcanic Rock (Cambrian/Late Proterozoic) at surface, covers 6 % of this area

Mafic Metavolcanic Rock - metamorphosed basaltic flows and tuffs, dark green to black; interbedded with felsic and intermediate metavolcanic rock and metamudstone.

Lithology: mafic metavolcanic rock; felsic metavolcanic rock; intermediate metavolcanic rock; metasedimentary rock

Intermediate Metavolcanic Rock (Cambrian/Late Proterozoic) at surface, covers 2 % of this area

Intermediate Metavolcanic Rock - metamorphosed andesitic tuffs and flows, medium to dark grayish green; minor felsic and mafic metavolcanic rock.

Lithology: intermediate metavolcanic rock; felsic metavolcanic rock; mafic metavolcanic rock

Metamudstone and Meta-Argillite (Cambrian/Late Proterozoic) at surface, covers 20 % of this area

Metamudstone and Meta-Argillite - bedding plane and axial-planar cleavage common; interbedded with metasandstone, meta-conglomerate, and metavolcanic rock.

Lithology: metasedimentary rock; meta-argillite; meta-conglomerate; metavolcanic rock

Volcanic Metaconglomerate (Cambrian/Late Proterozoic) at surface, covers 0.5 % of this area

Volcanic Metaconglomerate - includes metagraywacke and metamudstone.

Lithology: meta-conglomerate; metavolcanic rock; metasedimentary rock

Newark Supergroup, Chatham Group; Cumnock Formation (Triassic) at surface, covers 0.8 % of this area

Cumnock Formation - sandstone and mudstone, gray to black; coal beds and carbonaceous shale. Grades into Pekin and Sanford formations.

Lithology: sandstone; mudstone; coal; mixed clastic/carbonate

Diabase (Jurassic) at surface, covers < 0.1 % of this area

Diabase - dikes, gray to black.

Lithology: diabase

Metavolcanic-Epiclastic Rock (Cambrian/Late Proterozoic) at surface, covers 4 % of this area

Metavolcanic-Epiclastic Rock - metamorphosed argillite, mudstone, volcanic sandstone, and conglomerate, and volcanic rock.

Lithology: meta-argillite; meta-conglomerate; metasedimentary rock; metavolcanic rock

Newark Supergroup, Chatham Group; Sanford Formation (Triassic) at surface, covers 2 % of this area

Sanford Formation - conglomerate, fanglomerate, sandstone, and mudstone.

Lithology: conglomerate; sandstone; mudstone

Biotite Gneiss and Schist (Cambrian/Late Proterozoic) at surface, covers 0.6 % of this area

Biotite Gneiss and Schist - 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.

Lithology: biotite gneiss; mica schist; amphibolite; calc-silicate rock; granite