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

Geologic units in Roanoke county, Virginia

[Additional scientific data in this geographic area]

Layered Pyroxene Granulite (Proterozoic Y) at surface, covers 7 % of this area

Layered pyroxene granulite

Lithology: granulite

Lower Devonian, Silurian and Upper Ordovician Formations Undivided (Ordovician-Devonian) at surface, covers 1 % of this area

Lower Devonian, Silurian and Upper Ordovician Formations Undivided - Some landslides with intact stratigraphic units in Giles County. Includes: Skrt, Sm, Oun, Ous, Ou, Om. (Shrc, Okpl?)

Lithology: sandstone; shale; siltstone; limestone; mudstone; quartzite; arenite

Porphyritic Leucocharnockite (Proterozoic Y) at surface, covers 3 % of this area

Porphyritic Leucocharnockite - Leucocharnockite

Lithology: granite

Leucocratic Granulite and Gneiss (Proterozoic Y) at surface, covers 2 % of this area

Leucocratic granulite and gneiss.

Lithology: granulite; gneiss

Lower Ordovician and Upper Cambrian Formations Undivided (Cambrian-Ordovician) at surface, covers 5 % of this area

Lower Ordovician and Upper Cambrian Formations Undivided - Includes Pinesburg Station Dolomite, Rockdale Run Formation, Beekmantown Formation, Stonehenge Limestone and Conococheague Formation.

Lithology: limestone; dolostone (dolomite); chert; sandstone

Juniata, Reedsville, Trenton, and Eggleston Formations (Ordovician) at surface, covers 3 % of this area

Juniata, Reedsville, Trenton, and Eggleston Formations - Dusky-red shale and mudstone and sandstone; shale and limestone. Note: one area in southeastern Bland County has landslides with intact stratigraphic units.

Lithology: shale; mudstone; sandstone; limestone

Shady Dolomite (Cambrian) at surface, covers 0.8 % of this area

Shady Dolomite - Dolomite.

Lithology: dolostone (dolomite); limestone; shale

Chilhowee Group (Cambrian) at surface, covers 9 % of this area

Chilhowee Group - Appalachian Plateaus and Valley and Ridge: Quartzite, conglomerate, feldspathic sandstone, phyllite, and minor ferruginous sandstone and volcanic rocks. Blue Ridge Anticlinorium: Conglomerate, quartzite, metasiltstone, and phyllite.

Lithology: quartzite; conglomerate; sandstone; phyllite; meta-argillite; volcanic rock (aphanitic)

Rome Formation (Cambrian) at surface, covers 12 % of this area

Rome Formation - Dusky-red and green shale and siltstone, dolomite, and limestone.

Lithology: shale; siltstone; sandstone; dolostone (dolomite); limestone

Conococheague Formation (Cambrian) at surface, covers 0.7 % of this area

Conococheague Formation - Limestone, dolomite, and calcareous sandstone.

Lithology: limestone; dolostone (dolomite); sandstone

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

Layered biotite granulite and gneiss.

Lithology: gneiss; granulite

Brallier Formation (Devonian) at surface, covers 7 % of this area

Brallier Formation - Micaceous shale, siltstone, and sandstone.

Lithology: shale; siltstone; sandstone

Charnockite (Proterozoic Y) at surface, covers 2 % of this area

Charnockite.

Lithology: granitic gneiss

Moccasin or Bays Formation through Blackford Formation (Ordovician) at surface, covers 5 % of this area

Moccasin or Bays Formation through Blackford Formation - Dusky-red shale and mudstone; sandstone; limestone, in part cherty; and calcareous shale.

Lithology: shale; mudstone; sandstone; limestone; chert

Price Formation (Mississippian) at surface, covers 3 % of this area

Price Formation - Sandstone, conglomeratic sandstone, and shale with carbonaceous partings and impure coal beds.

Lithology: sandstone; shale; siltstone; limestone; conglomerate; coal

Porphyoblastic Biotite-Plagioclase Augen Gneiss (Proterozoic Y) at surface, covers 1 % of this area

Porphyoblastic biotite-plagioclase augen gneiss

Lithology: augen gneiss

Layered Porphyrobliastic Pyroxene Granulite (Proterozoic Y) at surface, covers 8 % of this area

Layered porphyroblastic pyroxene granulite

Lithology: granulite

Elbrook Formation (Cambrian) at surface, covers 5 % of this area

Elbrook Formation - Dolomite, shale, and minor limestone.

Lithology: dolostone (dolomite); limestone; shale; siltstone

Chemung Formation (redefined as Foreknobs Formation) (Devonian) at surface, covers 10 % of this area

Chemung Formation - Shale and sandstone with a few thin, quartz-pebble conglomerates and red-beds.

Lithology: shale; sandstone; conglomerate

Beekmantown Group (Ordovician) at surface, covers 2 % of this area

Beekmantown Group - Dolomite, limestone, and chert. Includes Pinesburg Station Dolomite, Rockdale Run Formation, Beekmantown Formation, Stonehenge Limestone, and Chepultepec Formation.

Lithology: dolostone (dolomite); limestone; chert

Biotite Granodiorite and Biotite Granite (Proterozoic Z) at surface, covers 0.1 % of this area

Biotite granodiorite, biotite granite

Lithology: granodiorite; granite

Millboro Shale and Needmore Formation (Devonian) at surface, covers 3 % of this area

Millboro Shale and Needmore Formation - Black, fissile shale; gray calcareous shale; Tioga metabentonite at top of Needmore.

Lithology: black shale; shale; bentonite; limestone

Lower Devonian and Silurian Formations Undivided (Silurian-Devonian) at surface, covers 4 % of this area

Lower Devonian and Silurian Formations Undivided - Some landslides with intact stratigraphic units in Craig County area. Includes: Dsu, Skrt, Sm. (Shrc?)

Lithology: sandstone; limestone; shale