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

Geologic units in Augusta county, Virginia

[Additional scientific data in this geographic area]

Conococheague Formation (Cambrian-Ordovician) at surface, covers 14 % of this area

Conococheague Formation - Limestone, dolomite, and calcareous sandstone.

Lithology: limestone; dolostone (dolomite); sandstone

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

Hampshire Formation - Dusky-red to grayish-red shale, mudrock, and sandstone.

Lithology: sandstone; limestone; shale

Juniata, Oswego, Martinsburg (Reedsville and Dolly Ridge), and Eggleston Formations (Ordovician) at surface, covers 2 % of this area

Juniata, Oswego, Martinsburg (Reedsville and Dolly Ridge), and Eggleston Formations - Dusky-red shale and mudstone and sandstone; graywacke; shale and sandstone; and limestone.

Lithology: shale; mudstone; sandstone; graywacke; limestone

Martinsburg and Oranda Formations (Ordovician) at surface, covers 8 % of this area

Martinsburg and Oranda Formations - Shale, sandstone, siltstone, and limestone.

Lithology: shale; sandstone; siltstone; limestone

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

Leucocharnockite

Lithology: granite

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)

Catoctin Formation - Metabasalt (Proterozoic Z-Cambrian) at surface, covers 2 % of this area

Catoctin Formation - Metabasalt.

Lithology: meta-basalt

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

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

Lithology: sandstone; shale; coal

Rome Formation (Cambrian) at surface, covers 0.3 % of this area

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

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

Shady Dolomite (Cambrian) at surface, covers 2 % of this area

Shady Dolomite - Dolomite.

Lithology: dolostone (dolomite); limestone; shale

Hampshire Formation (Devonian) at surface, covers < 0.1 % of this area

Hampshire Formation - non-marine shales and fine micaceous sandstones, mostly red to brownish-gray, including siltstone, sandstone and conglomerate. Generally distinguishable from the underlying Chemung by non-marine character and red color.

Lithology: shale; sandstone; siltstone; conglomerate

Waynesboro Formation (Cambrian) at surface, covers 4 % of this area

Waynesboro Formation - Dolomite, dusky-red and green shale, limestone, and sandstone.

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

Brallier Formation (Devonian) at surface, covers 6 % of this area

Brallier Formation - Micaceous shale, siltstone, and sandstone.

Lithology: shale; siltstone; sandstone

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

Charnockite.

Lithology: granitic gneiss

Lower Devonian and Silurian Formations Undivided (Silurian-Devonian) at surface, covers 0.2 % 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

Ridgeley Sandstone, Helderberg and Cayugan Groups (Silurian-Devonian) at surface, covers 1 % of this area

Ridgeley Sandstone, Helderberg and Cayugan Groups - Calcareous sandstone; partly cherty limestone; calcareous shale; fossiliferous.

Lithology: limestone; sandstone; shale

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

Edinburg Formation, Lincolnshire and New Market Limestones (Ordovician) at surface, covers 5 % of this area

Edinburg Formation, Lincolnshire and New Market Limestones - Black limestone and shale; gray limestone, in part cherty

Lithology: limestone; black shale; chert

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

Chemung Formation (redefined as Foreknobs Formation) (Devonian) at surface, covers 11 % of this area

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

Lithology: shale; sandstone; conglomerate

Pocono Group (Mississippian) at surface, covers < 0.1 % of this area

Pocono Group - predominantly hard gray massive sandstones, with some shale. In the Eastern Panhandle, has been divided into the Hedges, Purslane, and Rockwell Formations.

Lithology: sandstone; shale

Elbrook Formation (Cambrian) at surface, covers 10 % of this area

Elbrook Formation - Dolomite, shale, and minor limestone.

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

Keefer, Rose Hill, and Tuscarora Formations (Silurian) at surface, covers 2 % 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