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

Geologic units in Hardy county, West Virginia

[Additional scientific data in this geographic area]

Tuscarora Sandstone (Silurian) at surface, covers 2 % of this area

Tuscarora Sandstone - medium- to thick-bedded, white to gray or pinkish sandstone, fine to coarse, quartzitic, ridge-forming. Equivalent to the Clinch Sandstone of Tennessee.

Lithology: sandstone

Martinsburg Formation (Ordovician) at surface, covers 5 % of this area

Martinsburg Formation - predominantly gray to dark shale, yellowish in the upper portion. Contains scattered thin limestone and sandstone interbeds, particularly in the lower portion. The upper portion constitutes the Reedsville Shale.

Lithology: shale; limestone; sandstone

Quaternary Alluvium (Quaternary) at surface, covers 6 % of this area

Quaternary Alluvium - alluvial deposits of sand, gravel, silt, and clay.

Lithology: alluvium

Oriskany Sandstone and Helderberg Group, undivided (Devonian) at surface, covers 0.2 % of this area

Oriskany Sandstone and Helderberg Group, undivided - Oriskany Sandstone: sometimes designated Ridgeley in eastern West Virginia. White to brown coarse- to fine-grained, partly calcareous sandstone, locally pebbly or conglomeratic, and ridge-forming. May be white, nearly pure silica, and a source of glass sand, as at Berkeley Springs, Morgan County. Helderburg Group: mostly cherty limestone, with some sandstone and shale. Contains several named stratigraphic units, including the Keyser Formation, which is partly Silurian and includes the Clifton Forge Sandstone and Big Mountain Shale Members.

Lithology: sandstone; limestone; shale

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

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

Lithology: sandstone; limestone; shale

Chemung Group (Devonian) at surface, covers 11 % of this area

Chemung Group - gray to brown siltstone and sandstone with shale and conglomeratic interbeds; mainly marine and sparingly fossiliferous; boundaries gradational. Can be divided into the Voreknobs and Scherr Formations along the Allegheny Front. Parkhead Sandstone Member near base.

Lithology: siltstone; sandstone; shale; conglomerate

Juniata, Oswego, Martinsburg (Reedsville and Dolly Ridge), and Eggleston Formations (Ordovician) at surface, covers < 0.1 % 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

Juniata and Oswego Formations (Ordovician) at surface, covers 2 % of this area

Juniata and Oswego Formations - the Juniata is a thin-bedded, blocky, red sandstone and shale. In places it is underlain by the thick-bedded, gray Oswego Sandstone.

Lithology: sandstone; shale

McKenzie Formation and Clinton Group (Silurian) at surface, covers 3 % of this area

McKenzie Formation and Clinton Group - includes the McKenzie Formation, consisting of shale with thin limestone lenses; the dark Rochester Shale; the white Keefer Sandstone; and the Rose Hill predominantly red shale, with thin sandstone interbeds, some of which are called "iron sandstones" from their reddish-brown color and hematite content.

Lithology: shale; sandstone; limestone

Pocono Group (Mississippian) at surface, covers 2 % 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

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

Marcellus Formation and Needmore Shale, undivided (Devonian) at surface, covers 9 % of this area

Marcellus Formation and Needmore Shale, undivided - Marcellus Formation (part of Millboro Shale): predominantly gray-black to black thinly laminated non-calcareous pyritic shale. Contains one or more thin-bedded limestones, including the Purcell Member of Pennsylvania. Needmore Shale (part of Onesquethaw ("Onondaga") Group): predominantly dark grey or green, calcitic, mostly non-fissile shale. Gives strong "kick" on gamma ray logs. Tioga Bentonite near the top. Includes the black Beaver Dam Shale Member. Grades westward into the Huntersville Chert. Not mappable at scale of this map. Included with Dmn.

Lithology: shale; black shale; limestone; bentonite

Helderberg Group (Devonian) at surface, covers 4 % of this area

Helderberg Group - mostly cherty limestone, with some sandstone and shale. Contains several named stratigraphic units, including the Keyser Formation, which is partly Silurian and includes the Clifton Forge Sandstone and Big Mountain Shale Members.

Lithology: limestone; sandstone; shale

Harrell Shale (Devonian) at surface, covers 0.8 % of this area

Harrell Shale (part of Millboro Shale) - dark gray to black thinly laminated to fissile shale. Calcareous shale and limestone lenses near the base (Tully).

Lithology: shale; limestone

Tonoloway, Wills Creek, and Williamsport Formations (Silurian) at surface, covers 6 % of this area

Tonoloway, Wills Creek, and Williamsport Formations - includes the thin-bedded platy argillaceous limestones of the Tonoloway, the thin-bedded shale with fossiliferous limestones of the Wills Creek, the Bloomsburg red clastic facies, and the greenish-brown to white Williamsport Sandstone. The Wills Creek contains anhydrite and rock salt, the latter supplying brine from deep wells along the Ohio River.

Lithology: limestone; shale; sandstone; clastic; chemical

Mahantango Formation (Devonian) at surface, covers 5 % of this area

Mahantango Formation (part of Millboro Shale) - thickly laminated marine shale, siltstone, very fine sandstone, and some limestone, with an occasional coral reef or biostrome. Contains the Clearville and Chaneysville Siltstone Members of Pennsylvania.

Lithology: shale; sandstone; siltstone; limestone; coral

Hampshire Formation (Devonian) at surface, covers 25 % 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

Brallier Formation and Harrell Shale, undivided (Devonian) at surface, covers 6 % of this area

Brallier Formation and Harrell Shale, undivided - Brallier Formation : predominantly olive-gray to dark, thickly laminated marine shale, with considerable siltstone and thin sandstone lenses; mainly nonfossiliferous. Harrell Shale: dark gray to black thinly laminated to fissile shale. Calcareous shale and limestone lenses near the base (Tully).

Lithology: shale; siltstone; sandstone; limestone

Oriskany Sandstone and Huntersville Chert (Devonian) at surface, covers 12 % of this area

Oriskany Sandstone and Huntersville Chert - Oriskany Sandstone: sometimes designated Ridgeley in eastern West Virginia. White to brown coarse- to fine-grained, partly calcareous sandstone, locally pebbly or conglomeratic, and ridge-forming. May be white, nearly pure silica, and a source of glass sand, as at Berkeley Springs, Morgan County. Huntersville Chert (part of Onesquethaw ("Onondaga") Group): ranges from a nearly pure slightly calcitic or dolomitic chert to an inter-tonguing of such chert and the Needmore Shale. Grades westward in the subsurface to a limestone, commonly considered as "Onondaga". Contains the "glauconitic" Bobs Ridge Sandstone Member. Not mappable at scale of this map. Included with Do.

Lithology: sandstone; chert; limestone

Brallier Formation (Devonian) at surface, covers 1 % of this area

Brallier Formation - predominantly olive-gray to dark, thickly laminated marine shale, with considerable siltstone and thin sandstone lenses; mainly nonfossiliferous.

Lithology: shale; siltstone; sandstone