Nokomis Sandstone Member

Lithostratigraphy: Ottawa Limestone Megagroup >>Ancell Group >>Glenwood Formation >>Nokomis Sandstone Member
Chronostratigraphy: Paleozoic Erathem >>Ordovician System >>Champlainian Series >>Blackriveran Stage
Allostratigraphy: Tippecanoe 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)

H. B. Willman and T. C. Buschbach

Name

Original description

The Nokomis Sandstone Member of the Glenwood Formation (Templeton and Willman, 1963, p. 51).

Derivation

Named for Lake Nokomis.

Type section

Type location

The type section of the Nokomis Sandstone Member is located 1.5 miles east of Lake Nokomis in the bluff on the west side of the Mississippi River at Lock and Dam No. 1 in Minneapolis, Minnesota, where the member is 10.8 feet thick.

Stratigraphic relationships

The Nokomis Sandstone Member of the Glenwood Formation commonly includes all the sandstone of the formation in extreme northern Illinois and farther north. The Nokomis Sandstone Member rests on the St. Peter Sandstone and is overlain by the Harmony Hill Shale Member.

Extent and thickness

The Nokomis Sandstone Member has a maximum thickness of 11 feet in Illinois but is generally less than 5 feet and is absent in places.

Lithology

The Nokomis Member results from the merger northward of the Kingdom and Loughridge Sandstone Members beyond the margin of the intervening Daysville Dolomite Member. It has the typical Glenwood texture and generally rests sharply on the underlying St. Peter Sandstone.

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
8230	--