U.S. Geological Survey Home AASG Logo USGS HOME CONTACT USGS SEARCH USGS
National Geologic Map Database
Geologic Unit: Tygett
Search archives
Map showing publication footprint
  • Usage in publication:
    • Tygett Sandstone Member
  • Modifications:
    • Named
  • Dominant lithology:
    • Sandstone
    • Shale
  • AAPG geologic province:
    • Illinois basin
Publication:

Swann, D.H., 1963, Classification of Genevievian and Chesterian (Late Mississippian) rocks in Illinois: Illinois Geological Survey Report of Investigations, no. 216, 91 p.


Summary:

Name formally proposed in this report for middle clastic member of Clore Formation of Elviran age. Consists sandstone and shale. Overlain by Cora Member and underlain by Ford Station Member. Thickness 26 ft at type section.

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


Map showing publication footprint
  • Usage in publication:
    • Tygett Sandstone Member
  • Modifications:
    • Overview
  • AAPG geologic province:
    • Illinois basin
Publication:

Nelson, W.J., Devera, J.A., and Jacobson, R.J., 1991, Stratigraphy of the bedrock [includes abstract and introduction], IN Nelson, W.J., and others, Geology of the Eddyville, Stonefort, and Creal Springs quadrangles, southern Illinois: Illinois Geological Survey Bulletin, no. 96, p. 1-43, (incl. geologic maps, scale 1:24,000), Accompanied by the Creal Springs (IGQ-4), Eddyville (IGQ-5), and Stonefort (IGQ-6) Illinois Geol. Survey Geol. Quad. Ser. maps, scale 1:24,000. Available online.


Summary:

Clore Formation in the study area is subdivided into (ascending ) Cora, Tygett Sandstone, and Ford Station Members of Swann (1963). Unit can be correlated in outcrop and subsurface throughout southern IL. Well records show that thickness ranges from 95 to 120 ft in the Eddyville and Stoneford quads., and from 110 to 155 ft in the Creal Springs quad. Tygett Sandstone Member ranges from less than an inch to 20 ft thick in the Eddyville quad and from 15 to 50 ft thick in the Stonefort and Creal Springs quads. Tygett consists mostly of gray silty shale and siltstone to the east, but westward becomes a very fine to fine-grained sandstone. Age is Chesterian.

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


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 ([ ]).