USGS Home
Contact USGS
Search USGS

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

Geologic units in Washington county, Virginia

[Additional scientific data in this geographic area]

Konnarock Formation (Proterozoic Z) at surface, covers 1 % of this area

Konnarock Formation - Maroon diamictite, rhythmite, and arkose.

Lithology: sedimentary breccia; arkose

Hardy Creek Limestone through Dot Limestone (Ordovician) at surface, covers < 0.1 % of this area

Hardy Creek Limestone through Dot Limestone - Limestone, in part cherty; and calcareous shale. Includes Hardy Creek, Ben Hur, Woodway, Hurricane Bridge, Martin Creek, Rob Camp, Poteet, and Dot Limestones.

Lithology: limestone; shale; chert

Greenbrier Limestone (Mississippian) at surface, covers 7 % of this area

Greenbrier Limestone - Limestone, in part cherty, fossiliferous; shale.

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

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

Maccrady Shale and Price Formation - Includes: Maccrady Shale: Dusky-red and green shale and mudstone; and evaporite deposits. Price Formation: Sandstone, conglomeratic sandstone, and shale with carbonaceous partings and impure coal beds.

Lithology: sandstone; shale; mudstone; coal; evaporite

Unicoi Formation (Cambrian) at surface, covers 2 % of this area

Unicoi Formation - Sandstone and quartzite with phyllite, tuffaceous phyllite, conglomerate, and minor basalt.

Lithology: sandstone; quartzite; phyllite; conglomerate; basalt

Moccasin or Bays Formation through Blackford Formation (Ordovician) at surface, covers 1 % 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

Brallier Formation (Devonian) at surface, covers 2 % of this area

Brallier Formation - Micaceous shale, siltstone, and sandstone.

Lithology: shale; siltstone; sandstone

Mount Rogers Formation - Porphyritic felsite (Proterozoic Z) at surface, covers < 0.1 % of this area

Mount Rogers Formation - Porphyritic extrusive felsite

Lithology: felsic volcanic rock

Knobs Formation, Paperville Shale, Lenoir and Mosheim Limestone (Ordovician) at surface, covers 8 % of this area

Knobs Formation, Paperville Shale, Lenoir and Mosheim Limestone - Sandstone, conglomerate, siltstone; black, fissile shale; and limestone, in part cherty.

Lithology: sandstone; conglomerate; siltstone; black shale; limestone; chert

Chemung Formation (redefined as Foreknobs Formation) (Devonian) at surface, covers 1.0 % 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 11 % 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

Elk Park Plutonic Group - Biotite augen gneiss (Proterozoic Y) at surface, covers < 0.1 % of this area

Elk Park Plutonic Group - Biotite augen gneiss and porphyritic gneiss

Lithology: augen gneiss; quartz monzonite

Keefer, Rose Hill, and Tuscarora Formations (Silurian) at surface, covers 0.1 % of this area

Keefer, Rose Hill, and Tuscarora Formations - Quartzarenite, dusky-red shale, and sandstone, Some landslides with intact stratigraphic units in Craig County area..

Lithology: arenite; shale; sandstone

Elbrook Formation (Cambrian) at surface, covers 14 % of this area

Elbrook Formation - Dolomite, shale, and minor limestone.

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

Erwin and Hampton Formations (Cambrian) at surface, covers 2 % of this area

Erwin and Hampton Formations - Sandstone, quartzite, and shale.

Lithology: sandstone; quartzite; shale

Conococheague Formation (Cambrian-Ordovician) at surface, covers 5 % of this area

Conococheague Formation - Limestone, dolomite, and calcareous sandstone.

Lithology: limestone; dolostone (dolomite); sandstone

Millboro Shale, Huntersville Chert, and Rocky Gap Sandstone (Devonian) at surface, covers 2 % of this area

Millboro Shale, Huntersville Chert, and Rocky Gap Sandstone - Black, fissile shale; chert; and calcareous sandstone

Lithology: black shale; 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

Nolichucky and Honaker Formations (Cambrian) at surface, covers 3 % of this area

Nolichucky and Honaker Formations - Dolomitic shale; dolomite and minor chert.

Lithology: shale; dolostone (dolomite); chert

Pennington Group (Mississippian) at surface, covers 4 % of this area

Pennington Group - Shale, sandstone, dusky-red mudstone, conglomerate, siltstone, and limestone.

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

Knox Group (Cambrian-Ordovician) at surface, covers 8 % of this area

Knox Group - dolostone, limestone, sandstone. Includes the Mascot Dolomite, Kingsport Dolomite, Chepultepec Dolomite, Copper Ridge Dolomite. (Includes: Ob, Omk, Occo, Cco, Occc.)

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

Conococheague Formation (Cambrian) at surface, covers 7 % of this area

Conococheague Formation - Limestone, dolomite, and calcareous sandstone.

Lithology: limestone; dolostone (dolomite); sandstone

Mount Rogers Formation - Phenocryst-poor rhyolite (Proterozoic Z) at surface, covers < 0.1 % of this area

Mount Rogers Formation - Phenocryst-poor rhyolite

Lithology: rhyolite

Mount Rogers Formation - Conglomerate, graywacke, laminated siltstone, and shale. (Proterozoic Z) at surface, covers 0.5 % of this area

Mount Rogers Formation - Conglomerate, graywacke, laminated siltstone, and shale.

Lithology: conglomerate; graywacke; siltstone; shale; greenstone; rhyolite

Shady Dolomite (Cambrian) at surface, covers 1 % of this area

Shady Dolomite - Dolomite.

Lithology: dolostone (dolomite); limestone; shale

Cove Creek Limestone and Fido Sandstone (Mississippian) at surface, covers 3 % of this area

Cove Creek Limestone and Fido Sandstone - Limestone and calcareous sandstone.

Lithology: limestone; sandstone

Silurian Formations Undivided (Silurian) at surface, covers 7 % of this area

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

Lithology: sandstone; shale; limestone; arenite; conglomerate

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

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

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

Chilhowee Group (Cambrian) at surface, covers 0.9 % 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)