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National Geologic Map Database
Geologic Unit: Dug Gap
Map showing publication footprint
  • Usage in publication:
    • Dug Gap member
  • Modifications:
    • First used
  • Dominant lithology:
    • Sandstone
    • Shale
  • AAPG geologic province:
    • Appalachian basin
Publication:

Chowns, T.M., 1989, Stratigraphy of major thrust sheets in the Valley and Ridge province of Georgia, IN Fritz, W.J., ed., Excursions in Georgia geology: Georgia Geological Society Guidebook, Joint annual meeting of Geological Society of America, Southeastern Section, and Georgia Geological Society, Atlanta, GA, April 6-7, 1989, v. 9, no. 1, p. 211-238.


Summary:

Nomenclature of the Sequatchie Formation in the Clinchport thrust sheet follows usage of Zeigler (1989: Emory Univ. MS thesis). Zeigler divided the Sequatchie into "Ringgold" (base) and Dug Gap members. Dug Gap is 62 m thick and consists of 3 major facies: 1) 0.2 to 2.0-m thick beds of trough cross-bedded, medium to well sorted, coarse-grained, red to white sandstones; 2) poorly bedded, massive, bioturbated, argillaceous, red, coarse-grained sandstone; and 3) gray to red sandy shale with thin bioturbated sandstones and shale intraclast conglomerates, which are interbedded with facies 1 and 2. Unconformably underlies Red Mountain Formation. Age is Late Ordovician.

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


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

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"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 ( ).

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