Geologic units in Vance county, North Carolina

Metamorphosed Granitic Rock (Cambrian/Late Proterozoic) at surface, covers 38 % 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.

Foliated to Massive Granitic Rock (Permian/Pennsylvanian) at surface, covers 33 % of this area

Megacrystic to equigranular. Rolesville suite, Wise and Lemon Springs (?) intrusives.

Biotite Gneiss and Schist (Cambrian/Late Proterozoic) at surface, covers 9 % of this area

Inequigranular and megacrystic; in places contains garnet; interlayered and gradational with mica schist and amphibolite; includes small masses of granitic rock.

Metavolcanic-Epiclastic Rock (Cambrian/Late Proterozoic) at surface, covers 8 % of this area

Metamorphosed argillite, mudstone, volcanic sandstone, conglomerate, and volcanic rock.

Felsic Mica Gneiss (Cambrian/Late Proterozoic) at surface, covers 3 % of this area

Interlayered with graphitic mica schist and mica-garnet schist, commonly with kyanite; minor hornblende gneiss.

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

Minor biotite and pyrite; includes phyllonite, sheared fine-grained metasediment and metavolcanic rock.

Injected Gneiss (Cambrian/Late Proterozoic) at surface, covers 2 % of this area

Biotite gneiss and schist intruded by numerous sills and dikes of granite, pegmatite, and aplite; minor hornblende gneiss.

Lineated Felsic Mica Gneiss (Cambrian/Late Proterozoic) at surface, covers 2 % of this area

White to pink, with strong lineation of muscovite-biotite streaks and prismatic quartz aggregates; planar foliation and layering weak; minor mica schist and hornblende gneiss.

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

Interbedded felsic to mafic tuffs and flowrock.

Felsic Metavolcanic Rock (Cambrian/Late Proterozoic) at surface, covers 0.3 % of this area

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

Metamorphosed Quartz Diorite (Paleozoic/Late Proterozoic) at surface, covers 0.2 % of this area

Foliated to massive.

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

Foliated to massive.

Metatonalite (Proterozoic) at surface, covers < 0.1 % of this area

White to light-gray, medium- to coarse-grained, faintly foliated, locally porphyritic; ranges from granodiorite to quartz diorite. Mineralogy: quartz + plagioclase + biotite + microcline. This unit includes the Vance pluton of Horton and others (1993), dated at 571±17 Ma (U-Pb zircon; LeHuray, 1989).