The Foreknobs Formation contains massive sandstones; siltstone; "redbeds" of brownish-gray sandstone, siltstone, and shale containing scattered marine fossils; and occasional quartz-pebble conglomerate or conglomeratic sandstone beds.[2]
Stratigraphyedit
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.[3]
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.[4]
Rossbach and Dennison (1994) extended the Foreknobs into the Catawba syncline of southwestern Virginia.[5]
The Foreknobs is divided into the following Members, in ascending order: Mallow Member, Briery Gap Sandstone Member, Blizzard Member, Pound Sandstone Member, and Red Lick Member
Relative age dating places the Foreknobs in the Late Devonian.
Referencesedit
^Paleozoic Sedimentary Successions of the Virginia Valley & Ridge and Plateau
^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.
^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
^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.
^Rossbach, T.J., and Dennison, J.M., 1994, Devonian strata of Catawba syncline, near Salem, Virginia, IN Schultz, Art, and Henika, Bill, Fieldguides to Southern Appalachian structure, stratigraphy, and engineering geology: Virginia Polytechnic Institute and State University, Department of Geological Sciences Guidebook, Geological Society of America, Southeastern Section, Annual Meeting, Blacksburg, VA, April 7–9, 1994, no. 10, p. 95-126.
This article about a specific stratigraphicformation in Maryland is a stub. You can help Wikipedia by expanding it.
foreknobs, formation, devonian, mapped, bedrock, unit, pennsylvania, maryland, virginia, west, virginia, stratigraphic, range, frasnian, famennian, conglomerate, from, near, western, side, bridge, going, over, raystown, lake, huntingdon, county, pennsylvaniaty. The Devonian Foreknobs Formation is a mapped bedrock unit in Pennsylvania Maryland Virginia and West Virginia Foreknobs FormationStratigraphic range Frasnian Famennian 1 Conglomerate from Foreknobs Formation Rt 994 near western side of bridge going over Raystown Lake Huntingdon County PennsylvaniaTypesedimentaryUnit ofGreenland Gap GroupSub unitsMallow Member Briery Gap Sandstone Member Blizzard Member Pound Sandstone Member and Red Lick MemberUnderliesCatskill Formation or Hampshire Formation in VAOverliesScherr Formation or Brallier Formation in VAThickness1321 ft at type sectionLithologyPrimarySiltstone sandstone shaleOtherConglomerateLocationRegionAppalachian MountainsExtentPennsylvania Maryland Virginia West VirginiaType sectionNamed forFore Knobs of Allegheny FrontNamed byJ M Dennison 1970 Contents 1 Description 1 1 Stratigraphy 1 2 Fossils 1 3 Notable Exposures 2 Age 3 ReferencesDescription editThe Foreknobs Formation contains massive sandstones siltstone redbeds of brownish gray sandstone siltstone and shale containing scattered marine fossils and occasional quartz pebble conglomerate or conglomeratic sandstone beds 2 Stratigraphy edit 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 3 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 4 Rossbach and Dennison 1994 extended the Foreknobs into the Catawba syncline of southwestern Virginia 5 The Foreknobs is divided into the following Members in ascending order Mallow Member Briery Gap Sandstone Member Blizzard Member Pound Sandstone Member and Red Lick Member Fossils edit nbsp Foreknobs Formation containing abundant Mucrospirifer brachiopods from near upper reservoir of Bath County Pumped Storage Station Red beds within the Foreknobs contain scattered marine fossils such as brachiopods Notable Exposures edit Type section along WV Highway 42 0 48 km northwest of Scherr Grant County West VirginiaAge editRelative age dating places the Foreknobs in the Late Devonian References edit Paleozoic Sedimentary Successions of the Virginia Valley amp Ridge and Plateau 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 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 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 Rossbach T J and Dennison J M 1994 Devonian strata of Catawba syncline near Salem Virginia IN Schultz Art and Henika Bill Fieldguides to Southern Appalachian structure stratigraphy and engineering geology Virginia Polytechnic Institute and State University Department of Geological Sciences Guidebook Geological Society of America Southeastern Section Annual Meeting Blacksburg VA April 7 9 1994 no 10 p 95 126 nbsp This article about a specific stratigraphic formation in Maryland is a stub You can help Wikipedia by expanding it vte Retrieved from https en wikipedia org w index php title Foreknobs Formation amp oldid 1129367240, wikipedia, wiki, book, books, library,
