Historical:Dane Member

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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
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Lithostratigraphy: Ottawa Limestone Megagroup >>Platteville Group >>Pecatonica Formation >>Dane Member
Chronostratigraphy: Paleozoic Erathem >>Ordovician System >>Champlainian Series >>Blackriveran Stage
Allostratigraphy: Tippecanoe Sequence

Authors

H. B. Willman and T. C. Buschbach

Name Origin

The Dane Member of the Pecatonica Formation (Templeton and Willman, 1963, p. 76) is named for Dane County, Wisconsin.

Type Section

The type section of the Dane Member is a quarry and roadcut in Dane County, 4 miles north of New Glarus, Green County (SW NW NE 34, 5N-7E), where the member is 8.2 feet thick.

Extent and Thickness

The Dane Member commonly is 5-10 feet thick in the outcrop area, but it is as much as 60 feet in extreme southern Illinois.

Description

The Dane Member consists of slightly argillaceous, partly cherty, brown dolomite or limestone in thin to medium beds separated by thin shale partings.

Fossils

The Dane is the most fossiliferous of the Pecatonica members, and it is characterized regionally by the abundance of Opikina minnesotensis.

References

TEMPLETON, J. S., and H. B. WILLMAN, 1963, Champlainian Series (Middle Ordovician) in Illinois: Illinois State Geological Survey Bulletin 89, 260 p.

ISGS Codes

Stratigraphic Code Geo Unit Designation
8130
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