Stonefort Limestone Member

Jump to navigation Jump to search

Lithostratigraphy: Kewanee Group >>Spoon Formation >>Stonefort Limestone Member
Chronostratigraphy: Paleozoic Erathem >>Pennsylvanian Subsystem >>Desmoinesian Series
Allostratigraphy: Absaroka 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)

M. E. Hopkins and J. A. Simon


Original description

The Stonefort Limestone Member of the Spoon Formation (Henbest, 1928, p. 70-71).


Named for Stonefort, Williamson County.

Other names


Type section

Type location

The type locality consists of a roadcut and near-by ravines (NE SE 25, 10S- 4E), a correction of the location given by Wanless (1956, p. 9) (Kosanke et al., 1960, p. 33).

Type author(s)

Type status

Reference section

Reference location

Reference author(s)

Reference status

Stratigraphic relationships

Extent and thickness

It is seldom over 3 feet thick, and extends throughout the greater part of southern Illinois. It has been identified on geophysical logs of oil tests in much of the southern part of the Illinois Basin.


The Stonefort is a gray, fine-grained, marine limestone.




Well log characteristics


Age and correlation

Environments of deposition

Economic importance



HENBEST, L. G., 1928, Fusulinellas from the Stonefort Limestone Member of the Tradewater Formation: Journal of Paleontology, v. 2, p. 70-85.
KOSANKE, R. M., J. A. SIMON, H. R. WANLESS, and H. B. WILLMAN, 1960, Classification of the Pennsylvanian strata of Illinois: Illinois State Geological Survey Report of Investigations 214, 84 p.
WANLESS, H. R., 1956, Classification of the Pennsylvanian rocks of Illinois as of 1956: Illinois State Geological Survey Circular 217, 14 p.

ISGS Codes

Stratigraphic Code Geo Unit Designation
Penn symbol.pngtu-st