Dunkard Group








































Dunkard Group
Stratigraphic range: Pennsylvanian-Permian
Type Group
Sub-units
Waynesburg Formation, Washington Formation[1]
Underlies Igneous intrusives
Overlies Monongahela Formation
Lithology
Primary
Shale, sandstone, siltstone, coal
Other Limestone
Location
Region
 Ohio,  Pennsylvania,  West Virginia, and  Maryland
Country
 United States

The Permian Dunkard Group (Pd) is an area of rock, Early Permian in age, in the south of Ohio, southwestern Pennsylvania, West Virginia and the hilltops of the Georges Creek Basin of Maryland.[2] It is found primarily in Washington County. It is notable for being one of the few areas of Permian sediment east of the Mississippi River. In addition, it is the youngest surface rock in the state of Ohio.




Contents






  • 1 Description


  • 2 Fossil content


  • 3 See also


  • 4 References


  • 5 Further reading





Description


It consists of red and green shale, siltstone, and sandstone, with thin lenticular beds of argillaceous limestone and thin beds of impure coal The base of the layer contains thick-bedded, white conglomeratic sandstone. The layer's thickness is greater than 200 feet in Maryland.[2]


The fossils found in the Dunkard Group are similar to ones found in Texas and Oklahoma of similar age.



Fossil content




  • Dimetrodon

  • Ctenospondylus

  • Archaeothyris

  • Edaphosaurus

  • Eryops

  • Xenacanthus

  • Ophiacodon

  • Diploceraspis

  • Diplocaulus

  • Baldwinonus

  • Protorothyris

  • Diadectes

  • Isodectes

  • Sagenodus

  • Brachydectes

  • Phlegethontia




See also


  • Geology of Pennsylvania


References





  1. ^ Berryhill, Jr., Henry L.; Swanson, Vernon E. (1962). "Geological Survey research 1962; Short papers in geology and hydrology" (PDF). U. S Geological Survey Professional Paper. 450-C: 43–46. Retrieved 30 June 2018..mw-parser-output cite.citation{font-style:inherit}.mw-parser-output .citation q{quotes:"""""""'""'"}.mw-parser-output .citation .cs1-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/thumb/6/65/Lock-green.svg/9px-Lock-green.svg.png")no-repeat;background-position:right .1em center}.mw-parser-output .citation .cs1-lock-limited a,.mw-parser-output .citation .cs1-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/thumb/d/d6/Lock-gray-alt-2.svg/9px-Lock-gray-alt-2.svg.png")no-repeat;background-position:right .1em center}.mw-parser-output .citation .cs1-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/thumb/a/aa/Lock-red-alt-2.svg/9px-Lock-red-alt-2.svg.png")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-subscription,.mw-parser-output .cs1-registration{color:#555}.mw-parser-output .cs1-subscription span,.mw-parser-output .cs1-registration span{border-bottom:1px dotted;cursor:help}.mw-parser-output .cs1-ws-icon a{background:url("//upload.wikimedia.org/wikipedia/commons/thumb/4/4c/Wikisource-logo.svg/12px-Wikisource-logo.svg.png")no-repeat;background-position:right .1em center}.mw-parser-output code.cs1-code{color:inherit;background:inherit;border:inherit;padding:inherit}.mw-parser-output .cs1-hidden-error{display:none;font-size:100%}.mw-parser-output .cs1-visible-error{font-size:100%}.mw-parser-output .cs1-maint{display:none;color:#33aa33;margin-left:0.3em}.mw-parser-output .cs1-subscription,.mw-parser-output .cs1-registration,.mw-parser-output .cs1-format{font-size:95%}.mw-parser-output .cs1-kern-left,.mw-parser-output .cs1-kern-wl-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right,.mw-parser-output .cs1-kern-wl-right{padding-right:0.2em}


  2. ^ ab "Allegheny Plateau and Valley and Ridge". Geologic Map of Maryland. Maryland Geological Survey. 1968. Retrieved 2008-01-26.




Further reading



  • Anstey, Robert L.; Feldmann, Rodney M.; Hackathorn, Merrianne (1996). Fossils of Ohio. Columbus: State of Ohio, Dept. of Natural Resources, Division of Geological Survey. ISBN 0-931079-05-5.










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