Historical:Charter 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: Potsdam Sandstone Megagroup >>Mt. Simon Sandstone >>Charter Member
Chronostratigraphy: Paleozoic Erathem >>Cambrian System >>Croixan Series >>Dresbachian Stage
Allostratigraphy: Sauk Sequence

Author

T. C. Buschbach

Name Origin

The Charter Member of the Mt. Simon Sandstone (Templeton, 1950, p. 156), the uppermost member, is named for Charter Oak School, De Kalb County.

Type Section

The type section of the Charter Member of the Mt. Simon Sandstone is located 3.5 miles south of Charter Oak School, DeKalb County. It is the interval from 1381-1648 feet deep (sample set 1466) in the same boring as the Lacey Member.

Extent and Thickness

The Charter Member is 145-320 feet thick.

Description

It is medium- to fine-grained, partly conglomeratic sandstone with some red micaceous shale at or near the base.

References

TEMPLETON, J. S., 1950, Mt. Simon Sandstone in northern Illinois: Illinois Academy of Science Transactions, v. 43, p. 151-159.

ISGS Codes

Stratigraphic Code	Geo Unit Designation
8820	--