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National Geologic Map Database
Map showing publication footprint
  • Usage in publication:
    • Needmore shale
  • Modifications:
    • Named
  • Dominant lithology:
    • Shale
    • Limestone
  • AAPG geologic province:
    • Appalachian basin
Publication:

Willard, Bradford, and Cleaves, A.B., 1939, Ordovician-Silurian relations in Pennsylvania: Geological Society of America Bulletin, v. 50, no. 7, p. 1165-1198.


Summary:

Needmore shale proposed for dark- to medium-gray limy shale in Fulton Co., PA. Weathers greenish, olive, or olive drab. Limestone present as thin beds, lenses, and nodules; more plentiful in upper part. Contains Beaver Dam black shale member (new name) near middle in western Mifflin Co., PA. Thickness generally 100 to 150 ft west of Susquehanna River. Disconformably overlies Oriskany group. Underlies Selinsgrove limestone with gradational contact and supplants it southward; distinguished from Selinsgrove by greater portion of argillaceous material. Assigned to Onondaga group. Needmore is the Selinsgrove shale of White (1883).

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


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

Brett, C.E., and Ver Straeten, C.A., 1994, Stratigraphy and facies relationships of the Eifelian Onondaga Limestone (Middle Devonian) in western and central New York State, IN Brett, C.E., and Scatterday, James, eds., Field trip guidebook: New York State Geological Association Guidebook, 66th annual meeting, Rochester, NY, no. 66, p. 221-321.


Summary:

Selinsgrove Limestone Member, upper member of Needmore Shale (central PA), is direct equivalent of Onondaga Limestone of western and central NY. Also equivalent to Buttermilk Falls Limestone of eastern PA. Underlying strata of Needmore are therefore equivalent to the older Esopus to Schoharie Formations of NY.

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


Map showing publication footprint
  • Usage in publication:
    • Needmore Shale*
  • Modifications:
    • Biostratigraphic dating
  • AAPG geologic province:
    • Appalachian basin
Publication:

Harris, A.G., Stamm, N.R., Weary, D.J., Repetski, J.E., Stamm, R.G., and Parker, R.A., 1994, Conodont color alteration index (CAI) map and conodont-based age determinations for the Winchester 30' x 60' quadrangle and adjacent area, Virginia, West Virginia, and Maryland: U.S. Geological Survey Miscellaneous Field Studies Map, MF-2239, 1 sheet, 40 p., scale 1:100,000 [http://ngmdb.usgs.gov/Prodesc/proddesc_294.htm]


Summary:

Conodont biostratigraphy indicates that the Needmore Shale is of Early and earliest Middle Devonian age. Conodonts from the overlying Tioga Ash Bed suggest that the top of the Needmore is within the PO. C. COSTATUS Zone of Middle Devonian age.

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


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For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.

Asterisk (*) indicates usage by the U.S. Geological Survey. Other usages by state geological surveys.

"No current usage" (†) implies that a name has been abandoned or has fallen into disuse. Former usage and, if known, replacement name given in parentheses ( ).

Slash (/) indicates name does not conform with nomenclatural guidelines (CSN, 1933; ACSN, 1961, 1970; NACSN, 1983, 2005). This may be explained within brackets ([ ]).