Fredonia Limestone Member

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Lithostratigraphy: Mammoth Cave Limestone Megagroup >>Ste. Genevieve Limestone >>Fredonia Limestone Member
Chronostratigraphy: Paleozoic Erathem >>Mississippian Subsystem >>Valmeyeran Series >>Genevievian Stage
Allostratigraphy: Kaskaskia Sequence

Primary source

Willman, H. B., Elwood Atherton, T. C. Buschbach, Charles Collinson, John C. Frye, M. E. Hopkins, Jerry A. Lineback, and Jack A. Simon, 1975, Handbook of Illinois Stratigraphy: Illinois State Geological Survey Bulletin 95, 261 p.

Contributing author(s)

Elwood Atherton, Charles Collinson, and Jerry A. Lineback


Original description

The Fredonia Limestone Member of the Ste. Genevieve Limestone (Ulrich and Smith, 1905, p. 24, 40; Swann, 1963, p. 27, 66).


Named for Fredonia, Caldwell County, Kentucky (14-I-18).

Other names


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Stratigraphic relationships

The Fredonia Limestone Member is the lowest and thickest member of the Ste. Genevieve Limestone. The Fredonia originally included the dominantly limestone section from the base of the Rosiclare Sandstone to the top of the underlying St. Louis Limestone, but it was restricted by Swann (1963) to the limestone between the base of the Spar Mountain Member and the St. Louis Limestone.

Extent and thickness

The Fredonia is generally 80-100 feet thick, but from Effingham County north to Coles County it thins rapidly to 20 feet or less.


The limestone is light gray, mainly oolitic, cross-bedded, and crinoidal, but it includes some darker lithographic limestone beds like those in the St. Louis below.




Well log characteristics


Crinoids are present in the Fredonia Member.

Age and correlation

Environments of deposition

Economic importance

“McClosky”, “Oblong” and “lower McClosky” are informal names applied to producing zones in the Fredonia Limestone Member of the Ste. Genevieve Limestone.



SWANN, D. H., 1963, Classification of Genevievian and Chesterian (Late Mississippian) rocks of Illinois: Illinois State Geological Survey Report of Investigations 216, 91 p.
ULRICH, E. O., and W. S. T. SMITH, 1905, Lead, zinc, and fluorspar deposits of western Kentucky: USGS Professional Paper 36, 218 p.

ISGS Codes

Stratigraphic Code Geo Unit Designation