Geologic units in Forsyth county, North Carolina

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

Inequigranular and megacrystic; 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.

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

Megacrystic to equigranular. Churchland Plutonic Suite (Western group) - Churchland, Landis, and Mooresville intrusives.

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

Metagraywacke (biotite gneiss) interlayered and gradational with amphibolite and kyanite schist; minor ultramafic and granitic rock.

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

Metagabbro, metadiorite, and mafic plutonic-volcanic complexes.

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

Interlayered with biotite and hornblende gneiss and schist.

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

Megacrystic, in places contains amphibolite.

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

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

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

Megacrystic, well foliated; locally contains hornblende. Chapel Hill, Chatham, Farrington, Meadow Flats, Mt. Moriah, Parks Crossroads plutons, and Roxboro and Vance County suites.

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

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