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

Geologic units in Franklin county, Virginia

[Additional scientific data in this geographic area]

Fork Mountain Formation (Proterozoic Z-Cambrian) at surface, covers 5 % of this area

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

Lithology: mica schist; gneiss; quartzite; melange

Porphyoblastic Biotite-Plagioclase Augen Gneiss (Proterozoic Y) at surface, covers 4 % of this area

Porphyoblastic biotite-plagioclase augen gneiss

Lithology: augen gneiss

Ashe Formation - Moneta Gneiss (Proterozoic Z) at surface, covers 2 % of this area

Ashe Formation - Moneta Gneiss - Hornblende and hornblende-biotite gneiss

Lithology: mafic gneiss

Alligator Back Formation - Feldspathic metagraywacke (Proterozoic Z-Cambrian) at surface, covers 21 % of this area

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

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

Charnockite (Proterozoic Y) at surface, covers 0.7 % of this area

Charnockite.

Lithology: granitic gneiss

Layered Biotite Granulite and Gneiss (Proterozoic Y) at surface, covers 6 % of this area

Layered biotite granulite and gneiss.

Lithology: gneiss; granulite

Bassett Formation - Biotite gneiss and granite gneiss. (Proterozoic Z) at surface, covers 6 % of this area

Bassett Formation - Quartzofeldspathic biotite gneiss and granite gneiss.

Lithology: biotite gneiss; granitic gneiss

Biotite Granodiorite and Biotite Granite (Proterozoic Z) at surface, covers 0.4 % of this area

Biotite granodiorite, biotite granite

Lithology: granodiorite; granite

Bassett Formation - Amphibolite. (Proterozoic Z-Cambrian) at surface, covers 2 % of this area

Bassett Formation - Amphibolite.

Lithology: amphibolite; gneiss; schist

Ashe Formation- Amphibolite (Proterozoic Z) at surface, covers 2 % of this area

Ashe Formation - Amphibolite and garnet amphibolite

Lithology: amphibolite

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

Metagabbro

Lithology: metamorphic rock

Layered Quartzofeldspathic Augen Gneiss and Flaser Gneiss (Proterozoic Y) at surface, covers 8 % of this area

Layered quartzofeldspathic augen gneiss and flaser gneiss.

Lithology: felsic gneiss; flaser gneiss

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

Alaskite

Lithology: alkali-granite (alaskite)

Alligator Back Formation - Actinolite schist (Proterozoic Z-Cambrian) at surface, covers 6 % of this area

Alligator Back Formation - Actinolite schist

Lithology: schist

Porphyritic Leucocharnockite (Proterozoic Y) at surface, covers 1 % of this area

Porphyritic Leucocharnockite - Leucocharnockite

Lithology: granite

Ashe Formation - Biotite gneiss (Proterozoic Z) at surface, covers 29 % of this area

Ashe Formation - Biotite gneiss.

Lithology: biotite gneiss

Alligator Back Formation - Banded marble (Proterozoic Z-Cambrian) at surface, covers 0.2 % of this area

Alligator Back Formation - Banded marble

Lithology: marble; gneiss; schist

Candler Formation - Phyllite and schist (Cambrian) at surface, covers 0.9 % 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

Mafic Igneous Complex Undivided (Proterozoic Z-Cambrian) at surface, covers 3 % of this area

Mafic Igneous Complex Undivided - Mafic igneous complex.

Lithology: mafic metavolcanic rock

Ultramafic Rocks (Proterozoic Z-Cambrian) at surface, covers 0.3 % of this area

Ultramafic rocks

Lithology: ultramafic rock; schist