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Map showing publication footprint
  • Usage in publication:
    • Reedsville shale*
  • Modifications:
    • Named
  • Dominant lithology:
    • Shale
  • AAPG geologic province:
    • Appalachian basin
Publication:

Ulrich, E.O., 1911, Revision of the Paleozoic systems: Geological Society of America Bulletin, v. 22, p. 281-680.


Summary:

Named Reedsville shale for Reedsville, Mifflin Co., PA. Overlies Lower Trenton limestone and underlies the Oswego sandstone (Bald Eagle). Unit includes beds equivalent to Upper Trenton, Eden, and lower part of Maysville. Extends from central PA to southwestern VA. The Reedsville is of Late Ordovician age.

Source: GNU records (USGS DDS-6; Reston GNULEX).


Map showing publication footprint
  • Usage in publication:
    • Reedsville shale*
  • Modifications:
    • Overview
  • AAPG geologic province:
    • Appalachian basin
Publication:

Butts, Charles, and Moore, E.S., 1936, Geology and mineral resources of the Bellefonte quadrangle, Pennsylvania: U.S. Geological Survey Bulletin, 855, 111 p.


Summary:

In central PA the Reedsville shale consists of dark calcareous shale with thin layers of fossiliferous limestone; top 40 feet consists of thick-bedded calcareous sandstone containing ORTHORHYNCHULA and BYSSONICHIA (ORTHORHYNCHULA zone). Thickness is 1000 feet. Overlies the Trenton limestone and underlies the Oswego sandstone.

Source: GNU records (USGS DDS-6; Reston GNULEX).


Map showing publication footprint
  • Usage in publication:
    • Reedsville shale
  • Modifications:
    • Revised
  • AAPG geologic province:
    • Appalachian basin
Publication:

Kay, G.M., 1944, Middle Ordovician of central Pennsylvania: Journal of Geology, v. 52, no. 1, p. 97-116.


Summary:

The Reedsville shale is revised to exclude about 400 feet of dark brownish weathering shale at the base of the unit. This shale is named the Antes shale.

Source: GNU records (USGS DDS-6; Reston GNULEX).


Map showing publication footprint
  • Usage in publication:
    • Reedsville shale
  • Modifications:
    • Areal extent
  • AAPG geologic province:
    • Appalachian basin
Publication:

Rodgers, John, 1953, Geologic map of east Tennessee with explanatory text: Tennessee Division of Geology Bulletin, no. 58, pt. 2, 167 p.


Summary:

Geographically extended the Reedsville shale to eastern TN where it is mapped east of Kingston fault. Thickness is 250 to 400 feet. Overlies unit 4 of Chickamauga limestone and underlies the Sequatchie formation. The Reedsville was called Athens shale by Hayes (USGS Geol. Atlas of the US, Kingston folio, no. 4, 1894; USGS Geol. Atlas of the US, Cleveland folio, no. 20, 1895) and Sevier shale by Keith (USGS Geol. Atlas of the US, Maynardville folio, no. 75, 1901).

Source: Modified from GNU records (USGS DDS-6; Reston GNULEX).


Map showing publication footprint
  • Usage in publication:
    • Reedsville Formation
  • Modifications:
    • Revised
  • AAPG geologic province:
    • Appalachian basin
Publication:

Conlin, R.R., and Hoskins, D.M., 1962, Geology and mineral resources of the Mifflintown quadrangle, Pennsylvania: Pennsylvania Geological Survey Topographic and Geologic Atlas, 4th series, 126, 46 p., scale 1:24,000


Summary:

Revised the Reedsville to the Reedsville Formation. Consists of medium to dark gray, fissile shale at the base which grades into olive gray, thin-bedded shales, siltstones, and fine-grained sandstones which dominate in the upper part. The Reedsville is fossiliferous, especially in the upper part which contains the index fossil ORTHORHYNCHULA STEVENSONI. Thickness is 1500 feet. Both the upper and lower contact are gradational with the upper contact with the Bald Eagle Formation placed at the base of the first thick-bedded, resistant sandstone above the final occurrence of ORTHORHYNCHULA. Unit overlies the Salona Formation. The Reedsville is of Late Ordovician age.

Source: GNU records (USGS DDS-6; Reston GNULEX).


Map showing publication footprint
  • Usage in publication:
    • Reedsville Shale*
  • Modifications:
    • Revised
  • AAPG geologic province:
    • Appalachian basin
Publication:

Harris, L.D., 1965, Geologic map of the Wheeler quadrangle, Claiborne County, Tennessee, and Lee County, Virginia: U.S. Geological Survey Geologic Quadrangle Map, GQ-435, scale 1:24,000 [http://ngmdb.usgs.gov/Prodesc/proddesc_903.htm]


Summary:

Revised the Reedsville Shale to be included in the Chickamauga Group in TN. Unit is uppermost formation in group. Consists of pale olive gray shale with thin platy beds of calcareous siltstone and medium gray coquinoid limestone. Thickness is about 300 feet. Overlies the Trenton Limestone of the Chickamauga Group and underlies the Sequatchie Formation. The Reedsville is of Late Ordovician age.

Source: GNU records (USGS DDS-6; Reston GNULEX).


Map showing publication footprint
  • Usage in publication:
    • Reedsville Shale
  • Modifications:
    • Areal extent
  • AAPG geologic province:
    • Appalachian basin
Publication:

Patchen, D.G., 1967, Newburg gas development in West Virginia: West Virginia Geological Survey Circular, no. 6, 33 p.


Summary:

Geographically extended the Reedsville Shale to WV. Unit appears in stratigraphic column of figure 1. Overlies the Trenton Limestone and underlies the Oswego Sandstone. The Reedsville is equivalent to most of the Martinsburg Formation of previous WV county reports.

Source: GNU records (USGS DDS-6; Reston GNULEX).


Map showing publication footprint
  • Usage in publication:
    • Reedsville Formation
  • Modifications:
    • Geochronologic dating
  • AAPG geologic province:
    • Appalachian basin
Publication:

Lapham, D.M., and Root, S.I., 1971, Summary of isotopic age determinations in Pennsylvania: Pennsylvania Geological Survey Information Circular, 4th series, no. 70, 29 p.


Summary:

Isotopic dating of shale mylonite from the Reedsville Formation in PA reveals a K-Ar age of 372+/-8 Ma.

Source: GNU records (USGS DDS-6; Reston GNULEX).


Map showing publication footprint
  • Usage in publication:
    • Reedsville Formation
  • Modifications:
    • Overview
  • AAPG geologic province:
    • Appalachian basin
Publication:

Dean, S.L., Kulander, B.R., and Lessing, Peter, 1985, Geology of the Capon Springs, Mountain Falls, Wardensville, Woodstock, and Yellow Springs quadrangles, Hampshire and Hardy Counties, West Virginia: West Virginia Geological and Economic Survey Map, 26, scale 1:24,000


Summary:

The Reedsville Formation in eastern WV consists of dark shale that weathers to light yellow, tan, and red; sparsely fossiliferous and well developed cleavage. Thickness is 1500 to 2000 ft. Underlies the Oswego Sandstone and is equivalent to the Martinsburg Formation.

Source: GNU records (USGS DDS-6; Reston GNULEX).


Map showing publication footprint
  • Usage in publication:
    • Reedsville Formation
  • Modifications:
    • Overview
  • AAPG geologic province:
    • Appalachian basin
Publication:

Faill, R.T., Glover, A.D., and Way, J.H., 1989, Geology and mineral resources of the Blandburg, Tipton, Altoona, and Bellwood quadrangles, Blair, Cambria, Clearfield and Centre Counties, Pennsylvania: Pennsylvania Geological Survey Topographic and Geologic Atlas, 4th series, 86, 209 p., scale 1:24,000 and 1:48,000


Summary:

Reedsville has been traced throughout the Valley and Ridge province from central PA southwestward to western VA and eastern TN. Consists predominantly of medium-gray shale, which weathers to olive gray. Shale is quite fissile with no obvious bedding in lower part. Higher in the section, shale becomes slightly silty and unit becomes thin to medium bedded. At the top, siltstone constitutes more than 75 percent of the sequence. Only fossils found in study area are crinoid columnals. Gradationally overlies Antes Formation. Conformably underlies Bald Eagle Formation, where contact is placed at the base of the lowest sandstone. Thickness of 250+/-30 m calculated from dip and map-pattern width. Best exposure is along the Conrail tracks at the northeast end of Brush Mountain, in the Little Juniata River gap southeast of Tyrone, 2 km east of the eastern border of the Tipton quad. Elsewhere exposures are poor because of colluvial cover. Age is Late Ordovician.

Source: GNU records (USGS DDS-6; Reston GNULEX).


Map showing publication footprint
  • Usage in publication:
    • Reedsville Shale*
  • Modifications:
    • Revised
    • Areal extent
    • Age modified
  • AAPG geologic province:
    • Appalachian basin
Publication:

Ryder, R.T., 1992, Stratigraphic framework of Cambrian and Ordovician rocks in the central Appalachian basin from Morrow County, Ohio, to Pendleton County, West Virginia, IN Evolution of sedimentary basins; Appalachian basin: U.S. Geological Survey Bulletin, 1839-G, p. G1-G25.


Summary:

Extended from WV to subsurface of OH in cross section E-E'. Used for silty and calcareous gray shale located between Waverly arch in OH and Allegheny structural front in WV. Follows usage of Cardwell and others (1968; State map), Perry (1971, 1972), and Rader (1982). Differs from Reedsville Formation of Calvert (1964) in that his Reedsville included sediments now associated with Utica Shale of this report. Strata called Cincinnati Group by Wickstrom and Gray (1988) are here called Reedsville Shale. Correlates with Martinsburg Formation between North Mountain fault and Blue Ridge in VA. Age is Late Ordovician (approx. middle Edenian through Maysvillian) based on fossils. Conodont-based age of Shermanian through Maysvillian assigned by Diecchio (1985), and Diecchio and others (1985) is too old.

Source: GNU records (USGS DDS-6; Reston GNULEX).


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