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Map showing publication footprint
  • Usage in publication:
    • Cedar Mountain Conglomerate Member
  • Modifications:
    • Named
  • Dominant lithology:
    • Conglomerate
  • AAPG geologic province:
    • Piedmont-Blue Ridge province
    • Culpeper basin
Publication:

Lindholm, R.C., 1979, Geologic history and stratigraphy of the Triassic-Jurassic Culpeper basin, Virginia: Geological Society of America Bulletin, v. 90, no. 11, pts. 1-2, p. 995-997 (summary), 1702-1736 (microfiche).


Summary:

The Cedar Mountain Conglomerate Member of the Bull Run Formation is here named. It consists of greenstone pebbles and boulders in a matrix which is red when fresh and gray when weathered or metamorphosed. It occupies a belt 31 km (20 mi) long and 3 km (5 mi) wide along the western margin of the Culpeper basin. Thickness ranges from 240 to 1,400 m (800 to 4,600 ft). Age is Late Triassic and Early Jurassic.

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


Map showing publication footprint
  • Usage in publication:
    • Cedar Mountain Conglomerate Member†
  • Modifications:
    • Abandoned
  • AAPG geologic province:
    • Piedmont-Blue Ridge province
Publication:

Lee, K.Y., and Froelich, A.J., 1989, Triassic-Jurassic stratigraphy of the Culpeper and Barboursville basins, Virginia and Maryland: U.S. Geological Survey Professional Paper, 1472, 52 p.


Summary:

The Cedar Mountain Conglomerate Member of the Bull Run Formation is here abandoned. It is replaced by the Mountain Run Member of the Tibbstown Formation.

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


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

Asterisk (*) indicates published by U.S. Geological Survey authors.

"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 conflicts with nomenclatural guidelines (CSN, 1933; ACSN, 1961, 1970; NACSN, 1983, 2005, 2021). May be explained within brackets ([ ]).

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