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Mineral Resources > Online Spatial Data > Geology > by state > Virginia Geology

Geologic units in Patrick county, Virginia

[Additional scientific data in this geographic area]

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

Amphibolite - equigranular, massive to well foliated, dioritic to basaltic dikes and sills; variably metamorphosed.

Lithology: amphibolite; basalt; diorite

Leatherwood Granite (Cambrian) at surface, covers 5 % of this area

Leatherwood Granite - Granite

Lithology: granite

Felsic Volcanic and Volcaniclastic Rocks (Proterozoic Z) at surface, covers < 0.1 % of this area

Felsic volcanic and volcaniclastic rocks.

Lithology: felsic volcanic rock; mixed clastic/volcanic

Bassett Formation - Amphibolite. (Proterozoic Z-Cambrian) at surface, covers 3 % of this area

Bassett Formation - Amphibolite.

Lithology: amphibolite; gneiss; schist

Ashe Formation- Amphibolite (Proterozoic Z) at surface, covers 0.3 % of this area

Ashe Formation - Amphibolite and garnet amphibolite

Lithology: amphibolite

Rich Acres Formation (Cambrian) at surface, covers 1 % of this area

Rich Acres Formation - Norite, metagabbro, and diorite.

Lithology: norite; gabbro; diorite

Bassett Formation - Biotite gneiss and granite gneiss. (Proterozoic Z) at surface, covers 11 % of this area

Bassett Formation - Quartzofeldspathic biotite gneiss and granite gneiss.

Lithology: biotite gneiss; granitic gneiss

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

Fork Mountain Formation (Proterozoic Z-Cambrian) at surface, covers 20 % of this area

Fork Mountain Formation - Quartzose mica schist, garnet-biotite gneiss, calc-silicate quartzite, and melange.

Lithology: mica schist; gneiss; quartzite; melange

Alligator Back Formation - Feldspathic metagraywacke (Proterozoic Z-Cambrian) at surface, covers 48 % of this area

Alligator Back Formation - Meta-argillite is feldspathic metagraywacke; graphitic mica schist, and quartzite.

Lithology: meta-argillite; schist; quartzite; melange; marble; gneiss

Metamorphosed Granitic Rock (Ordovician/Cambrian) at surface, covers < 0.1 % of this area

Metamorphosed Granitic Rock (455-540 my) - equigranular to megacrystic, foliated to massive. Includes Toluca Granite.

Lithology: metamorphic rock

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

Banded Gneiss - interlayered with calc-silicate rock, metaconglomerate, amphibolite, sillimanite-mica schist, and granitic rock.

Lithology: gneiss; metasedimentary rock; amphibolite; mica schist; granite

Alligator Back Formation; Mica schist and phyllite (Late Proterozoic) at surface, covers < 0.1 % of this area

Mica schist and phyllite - laminated to thin layered; interlayered with minor biotite-muscovite gneiss and amphibolite.

Lithology: mica schist; phyllite; gneiss; amphibolite

Mafic Igneous Complex Undivided (Proterozoic Z-Cambrian) at surface, covers 0.5 % of this area

Mafic Igneous Complex Undivided - Mafic igneous complex.

Lithology: mafic metavolcanic rock

Ultramafic Rocks (Proterozoic Z-Cambrian) at surface, covers < 0.1 % of this area

Ultramafic rocks

Lithology: ultramafic rock; schist

Candler Formation - Phyllite and schist (Cambrian) at surface, covers 2 % of this area

Candler Formation - Phyllite in central Blue Ridge Anticlinorium; Phyllite, metasiltstone and quartz-mica schist in southwest Blue Ridge Anticlinorium

Lithology: phyllite; schist; metasedimentary rock

Alligator Back Formation; Gneiss (Late Proterozoic) at surface, covers < 0.1 % of this area

Gneiss - finely laminated to thin layered; locally contains massive gneiss and micaceous granule conglomerate; includes schist, phyllite, and amphibolite.

Lithology: gneiss; conglomerate; schist; phyllite; amphibolite

Alligator Back Formation - Actinolite schist (Proterozoic Z-Cambrian) at surface, covers 8 % of this area

Alligator Back Formation - Actinolite schist

Lithology: schist

Ashe Formation - Biotite gneiss (Proterozoic Z) at surface, covers 0.5 % of this area

Ashe Formation - Biotite gneiss.

Lithology: biotite gneiss