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

Geologic units in Forsyth county, North Carolina

[Additional scientific data in this geographic area]

Granitic Rock (Permian/Pennsylvanian) at surface, covers 26 % of this area

Granitic Rock (265-325 my) - megacrystic to equigranular. Castalia, Lillington, Medoc Mountain, Sims, Contentnea Creek (?), and Elm City (?) intrusives.

Lithology: granite

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

Mica Schist - Garnet, staurolite, kyanite, or sillimanite occur locally; lenses and layers of quartz schist, micaceous quartzite, calc-silicate rock, biotite gneiss, amphibolite, and phyllite.

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

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

Metagraywacke and Muscovite-Biotite Schist - metagraywacke (biotite gneiss) interlayered and gradational with muscovite-biotite schist; minor marble and granitic rock.

Lithology: metasedimentary rock; mica schist; marble; granite

Metamorphosed Granitic Rock (Cambrian/Late Proterozoic) at surface, covers 0.2 % of this area

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

Lithology: metamorphic rock

Granitic Gneiss (Late Middle Proterozoic) at surface, covers 5 % of this area

Granitic Gneiss (1192 my) - megacrystic, in places contains amphibolite.

Lithology: granitic gneiss; amphibolite

Metamorphosed Mafic Rock (Paleozoic/Late Proterozoic) at surface, covers 7 % of this area

Metamorphosed Mafic Rock - metagabbro, metadiorite, and mafic plutonic-volcanic complexes.

Lithology: metamorphic rock

Biotite Gneiss and Schist (Cambrian/Late Proterozoic) at surface, covers 45 % 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

Metagraywacke, Amphibolite, and Kyanite Schist (Cambrian/Late Proterozoic) at surface, covers 9 % of this area

Metagraywacke, Amphibolite, and Kyanite Schist - metagraywacke (biotite gneiss) interlayered and gradational with amphibolite and kyanite schist; minor ultramafic and granitic rock.

Lithology: metasedimentary rock; amphibolite; schist; ultramafic intrusive rock; granite

Felsic Mica Gneiss (Cambrian/Late Proterozoic) at surface, covers 6 % of this area

Felsic Mica Gneiss - interlayered with biotite and hornblende gneiss and schist.

Lithology: felsic gneiss; mafic gneiss; biotite gneiss; mica schist