Historical:O'Nan Coal Member

	Handbook of Illinois Stratigraphy
Series	Bulletin 95
Author	H. B. Willman, Elwood Atherton, T. C. Buschbach, Charles Collinson, John C. Frye, M. E. Hopkins, Jerry A. Lineback, Jack A. Simon
Date	1975
Link	Web page
PDF	PDF file
Store	ISGS Store

	Handbook of Illinois Stratigraphy
Series	Bulletin 95
Author	H. B. Willman, Elwood Atherton, T. C. Buschbach, Charles Collinson, John C. Frye, M. E. Hopkins, Jerry A. Lineback, Jack A. Simon
Date	1975
Link	Web page
PDF	PDF file
Store	ISGS Store

Lithostratigraphy: Kewanee Group >>Spoon Formation >>ONan Coal Member
Chronostratigraphy: Paleozoic Erathem >>Pennsylvanian Subsystem >>Desmoinesian Series
Allostratigraphy: Absaroka Sequence

Authors

M. E. Hopkins and J. A. Simon

Name Origin

The O'Nan Coal Member of the Spoon Formation (Kosanke et al., 1960, p. 32) is named for Dennis O'Nan Ditch, which flows across the tip of Indian Hill, Union County, Kentucky, the type locality (Glenn, 1912, p. 25).

Other Names

It previously was called the Curlew Coal (Owen, 1856, p. 47).

Correlation

It is now believed to be equivalent to the Bidwell Coal.

Extent and Thickness

The O'Nan Coal is generally thin, seldom over 1 foot thick in its scattered occurrences in southern Illinois.

References

GLENN, L. C., 1912, A geological reconnaissance of the Tradewater River region, with special reference to the coal beds: Kentucky Geological Survey Bulletin 17, 75 p.
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.
OWEN, D. D., 1856, Report of the geological survey in Kentucky made during the years 1854 and 1855: Kentucky Geological Survey Bulletin, v. I, Series 1, 416 p.

ISGS Codes

Stratigraphic Code	Geo Unit Designation
3434	--