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National Geologic Map Database
Map showing publication footprint
  • Usage in publication:
    • Loyalhanna Limestone Member
  • Modifications:
    • Overview
  • Dominant lithology:
    • Limestone
    • Sandstone
  • AAPG geologic province:
    • Appalachian basin
Publication:

Brezinski, D.K., 1989, The Mississippian System in Maryland: Maryland Geological Survey Report of Investigations, no. 52, 75 p.


Summary:

Greenbrier Formation is here revised in western MD to include (ascending) Loyalhanna, Deer Valley, Savage Dam (new name), and Wymps Gap Members. In study area, typically characterized by high quartz sand content (locally >50%) and medium- to large-scale festoon cross-bedding. Thickness ranges from <20 to >30 ft. Lithology ranges from a sandy lime grainstone to a calcareous sandstone, green-gray to red-brown in color, and locally a gray marlstone. Commonly contains lower percentage of terrigenous quartz in western MD than in PA. Uppermost layer is tan argillaceous dolomitic siltstone or a red calcareous siltstone that allows easy recognition of contact with Deer Valley Member. Unconformably(?) overlies Purslane Formation. Age is Meramecian.

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


Map showing publication footprint
  • Usage in publication:
    • Loyalhanna Limestone Member*
  • Modifications:
    • Biostratigraphic dating
  • AAPG geologic province:
    • Appalachian basin

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 ([ ]).