Scherr Formation

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Scherr Formation
Stratigraphic range: Late Devonian
Typesedimentary
Unit ofGreenland Gap Group
Sub-unitsMinnehaha Springs Member
Underlies Foreknobs Formation
Overlies Brallier Formation
Thickness1,004 ft (306 m) at type section
Lithology
Primary Shale
Other Siltstone
Location
Region Appalachian Mountains
ExtentPennsylvania, Maryland, Virginia, West Virginia
Type section
Named for Scherr, West Virginia
Named byJ. M. Dennison, 1970

The Devonian Scherr Formation is a mapped bedrock unit in Pennsylvania, Maryland, Virginia and West Virginia.

Contents

Description

The Scherr Formation consists predominantly of siltstone and shale. Lower part of unit includes considerable fine-grained sandstone, while upper two thirds contains almost no sandstone. It weathers light olive gray. [1]

Stratigraphy

Dennison (1970) renamed the old Chemung Formation the Greenland Gap Group and divided it into the lower Scherr Formation and the upper Foreknobs Formation. De Witt (1974) extended the Scherr and Foreknobs into Pennsylvania but did not use the term Greenland Gap Group. [2]

Boswell et al. (1987), does not recognize the Scherr and Foreknobs Formations in the subsurface of West Virginia, and thus, these formations are reduced from "group" to "formation" as the Greenland Gap Formation. [3]

The Minnehaha Springs Member is a "clastic bundle" consisting of interbedded medium gray siltstone and olive-gray shale with some grayish-red siltstone and shale and some sandstone. It is interpreted as turbidites. [4] This same member is proposed to exist at the base of the Scherr's lateral equivalent, the Lock Haven Formation. [5]

Scherr Formation within a geological cross section of the United States USGS 2006 1237 Fig7b.gif
Scherr Formation within a geological cross section of the United States

Notable outcrops

Age

Relative age dating places the Scherr in the late Devonian.

Paleontology

The Scherr Formation is the likely origin of the trace fossil Thinopus , which was described in 1896 by Othniel Charles Marsh as the earliest known tetrapod (land vertebrate). Later research, however, identified this fossil as coprolites (fossilized feces) of fishes. [6]

Related Research Articles

Scherr is an unincorporated community in Grant County, West Virginia, United States. The community's name is pronounced like "sheer." Scherr lies to the west of the community of Greenland at the crossroads of West Virginia Route 42, West Virginia Route 93, and U.S. Route 48. Scherr is home to a rock quarry, asphalt plant, and a small country store.

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<span class="mw-page-title-main">Bloomsburg Formation</span>

The Silurian Bloomsburg Formation is a mapped bedrock unit in Pennsylvania, New Jersey, New York and Maryland. It is named for the town of Bloomsburg, Pennsylvania, in which it was first described. The Bloomsburg marked the first occurrence of red sedimentary rocks in the Appalachian Basin.

<span class="mw-page-title-main">Martinsburg Formation</span> Geologic formation in the eastern United States

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<span class="mw-page-title-main">Reedsville Formation</span> Rock formation in the USA

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<span class="mw-page-title-main">Wills Creek Formation</span> Bedrock unit in the Eastern United States

Wills Creek Formation is a mapped Silurian bedrock unit in Pennsylvania, Maryland, Virginia, and West Virginia.

<span class="mw-page-title-main">Hamilton Group</span> Geological Group in North America

The Hamilton Group is a Devonian-age geological group which is located in the Appalachian region of the United States. It is present in New York, Pennsylvania, Maryland, Ohio, West Virginia, northwestern Virginia and Ontario, Canada, and is mainly composed of marine shale with some sandstone.

The Devonian Mahantango Formation is a mapped bedrock unit in Pennsylvania, West Virginia, and Maryland. It is named for the North branch of the Mahantango Creek in Perry and Juniata counties in Pennsylvania. It is a member of the Hamilton Group, along with the underlying the Marcellus Formation Shale. South of Tuscarora Mountain in south central Pennsylvania, the lower members of this unit were also mapped as the Montebello Formation. Details of the type section and of stratigraphic nomenclature for this unit as used by the U.S. Geological Survey are available on-line at the National Geologic Map Database.

<span class="mw-page-title-main">Marcellus Formation</span> Middle Devonian age unit of sedimentary rock

The Marcellus Formation or the Marcellus Shale is a Middle Devonian age unit of sedimentary rock found in eastern North America. Named for a distinctive outcrop near the village of Marcellus, New York, in the United States, it extends throughout much of the Appalachian Basin.

<span class="mw-page-title-main">Huntley Mountain Formation</span> Bedrock unit in Pennsylvania, United States

The Huntley Mountain Formation is a late Devonian and early Mississippian mapped bedrock unit in Pennsylvania, in the United States.

<span class="mw-page-title-main">Lock Haven Formation</span>

The Lock Haven Formation is a Devonian mapped bedrock unit in Pennsylvania, in the Appalachian Mountains of the United States.

<span class="mw-page-title-main">Bedford Shale</span> Geological formation in the United States

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<span class="mw-page-title-main">Old Port Formation</span>

The Devonian Old Port Formation is a mapped bedrock unit in Pennsylvania, USA. Details of the type section and of stratigraphic nomenclature for this unit as used by the U.S. Geological Survey are available on-line at the National Geologic Map Database. Current nomenclature usage by U.S. Geological Survey restricts the name Old Port Formation to Pennsylvania, but correlative units are present in adjacent states.

<span class="mw-page-title-main">Foreknobs Formation</span> Geological formation in the United States

The Devonian Foreknobs Formation is a mapped bedrock unit in Pennsylvania, Maryland, Virginia, and West Virginia.

<span class="mw-page-title-main">Rockwell Formation</span>

The Rockwell Formation is a late Devonian and early Mississippian mapped bedrock unit in West Virginia, Maryland, and Pennsylvania, in the United States.

<span class="mw-page-title-main">Glenshaw Formation</span> Geological formation in the United States

The Glenshaw Formation is a mapped sedimentary bedrock unit in Pennsylvania, Maryland, West Virginia, and Ohio, of Pennsylvanian age. It is the lower of two formations in the Conemaugh Group, the upper being the Casselman Formation. The boundary between these two units is the top of the marine Ames Limestone. The Conemaugh Group overlies the Upper Freeport coal bed of the Allegheny Formation and underlies the Pittsburgh coal seam of the Monongahela Group.

<span class="mw-page-title-main">Brallier Formation</span> Geologic formation in the United States

The Devonian Brallier Formation is a mapped bedrock unit in Pennsylvania, Maryland, West Virginia, and Virginia.

The Devonian Harrell Formation is a mapped bedrock unit in Pennsylvania, Maryland, West Virginia, and Virginia.

<span class="mw-page-title-main">Bluefield Formation</span> Geologic formation in West Virginia, United States

The Bluefield Formation is a geologic formation in West Virginia. It preserves fossils dating back to the Mississippian subperiod of the Carboniferous period. Sediments of this age formed along a large marine basin lying in the region of what is now the Appalachian Plateau. The Bluefield Formation is the lowest section of the primarily siliciclastic Mauch Chunk Group, underlying the Stony Gap Sandstone Member of the Hinton Formation and overlying the limestone-rich Greenbrier Group.

<span class="mw-page-title-main">Elbert Formation</span>

The Elbert Formation is a geologic formation that crops out in the San Juan Mountains of southwestern Colorado. The formation contains fossils indicating it is upper Devonian in age.

References

  1. Dennison, J.M., 1970, Stratigraphic divisions of Upper Devonian Greenland Gap Group ("Chemung Formation") along Allegheny Front in West Virginia, Maryland, and Highland County, Virginia: Southeastern Geology, v. 12, no. 1, p. 53-82.
  2. de Witt, Wallace, Jr., 1974, Geologic map of the Beans Cove and Hyndman quadrangles and part of the Fairhope quadrangle, Bedford County, Pennsylvania: U.S. Geological Survey Miscellaneous Investigations Series Map, I-801, 6 p., 1 sheet, scale 1:24,000
  3. Boswell, R.M., Donaldson, A.C., and Lewis, J.S., 1987, Subsurface stratigraphy of the Upper Devonian and Lower Mississippian of northern West Virginia: Southeastern Geology, v. 28, no. 2, p. 105-131.
  4. Lyke, W.L., 1986, The stratigraphy, paleogeography, depositional environment, faunal communities, and general petrology of the Minnehaha Springs Member of the Scherr Formation: Southeastern Geology, v. 26, no. 3, p. 173-192.
  5. Warne, A.G., and McGhee, G.R., Jr., 1991, Stratigraphic subdivisions of the Upper Devonian Scherr, Foreknobs, and Lock Haven Formations near the Allegheny Front of central Pennsylvania: Northeastern Geology, v. 13, no. 2, p. 96-109.
  6. Lucas, Spencer G. (2015). "Thinopus and a critical review of Devonian tetrapod footprints". Ichnos. 22 (3–4): 136–154. Bibcode:2015Ichno..22..136L. doi:10.1080/10420940.2015.1063491. S2CID   130053031.