Geologic units in Iredell county, North Carolina

Additional scientific data in this geographic area

Biotite Gneiss and Schist (Cambrian/Late Proterozoic) at surface, covers 31 % of this area

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.

Amphibolite and Biotite Gneiss (Cambrian/Late Proterozoic) at surface, covers 24 % of this area

Interlayered; minor layers and lenses of hornblende gneiss, metagabbro, mica schist, and granitic rock.

Fine-grained Biotite Gneiss (Cambrian/Late Proterozoic) at surface, covers 14 % of this area

Massive to strongly foliated; minor layers of amphibolite and muscovite schist.

Granitic Rock (Permian/Pennsylvanian) at surface, covers 8 % of this area

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

Mica Schist (Cambrian/Late Proterozoic) at surface, covers 7 % 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.

Metamorphosed Quartz Diorite (Paleozoic/Late Proterozoic) at surface, covers 3 % of this area

Foliated to massive.

Battleground Formation (Late Proterozoic) at surface, covers 3 % of this area

Quartz-sericite schist with metavolcanic rock, quartz-pebble metaconglomerate, kyanite-sillimanite quartzite, and garnet-quartz rock.

Fine-grained Biotite Gneiss (Cambrian/Late Proterozoic) at surface, covers 3 % of this area

Strongly foliated; minor layers of amphibolite and muscovite schist.

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

Metamorphosed basaltic to andesitic tuffs and flows, grayish green to black. Locally includes hypabyssal intrusives and minor felsic metavolcanic rock.

Metamorphosed Mafic Rock (Paleozoic/Late Proterozoic) at surface, covers 1 % of this area

Metagabbro, metadiorite, and mafic plutonic-volcanic complexes.

Meta-ultramafic Rock (Paleozoic/Late Proterozoic) at surface, covers 1 % of this area

Metamorphosed dunite, local peridotite, serpentinite, soapstone, and other ultramafic rock. Only larger bodies shown.

Metamorphosed Granitic Rock (Ordovician/Cambrian) at surface, covers 1 % of this area

Equigranular to megacrystic, foliated to massive. Includes Toluca Granite.

Metavolcanic Rock (Cambrian/Late Proterozoic) at surface, covers 1 % of this area

Interbedded felsic to mafic tuffs and flowrock.

Granitic Rock (Devonian/Ordovician) at surface, covers 0.4 % of this area

Locally pinkish gray, massive to weakly foliated; contains hornblende.

Foliated to Massive Granitic Rock (Permian/Pennsylvanian) at surface, covers 0.3 % of this area

Megacrystic to equigranular. High Shoals Granite.

Amphibolite (Cambrian/Late Proterozoic) at surface, covers 0.2 % of this area

Metamorphosed mafic extrusive and intrusive rock; includes hornblende gneiss, thin layers of mica schist, calc-silicate rock, and, rarely, marble. Also includes small masses of metadiorite and metagabbro.

Quartzite (Cambrian/Late Proterozoic) at surface, covers 0.1 % of this area

Massive to well foliated; contains andalusite, kyanite, or sillimanite, chloritoid, and pyrite.