Brickeys Member
Lithostratigraphy: Ottawa Limestone Megagroup >>Platteville Group >>Plattin Subgroup >>Mifflin Formation >>Brickeys 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. Wilman and T. C. Buschbach
Name
Original description
The Brickeys Member of the Mifflin Formation (Templeton and Willman, 1963, p. 81).
Derivation
Named for Brickeys, Ste. Genevieve County, Missouri, which is 3 miles east of the type section.
Other names
History/background
Type section
Type location
The type section of the Brickeys Member is located in a quarry on the east side of Missouri Highway 25 (SE SW SE 28, 39N-7E), where the member is 15.5 feet thick.
Type author(s)
Type status
Reference section
Reference location
Reference author(s)
Reference status
Stratigraphic relationships
Extent and thickness
The Brickeys Member is commonly 13-20 feet thick in the outcrop area in Missouri but is as much as 40 feet thick in subsurface in southern Illinois. Where locally differentiated in the northern outcrop area, it is 1-2 feet thick.
Lithology
In the southern area much of the Brickeys Member is relatively pure, brown, lithographic limestone, but it contains a few beds of gray to buff, argillaceous limestone and dolomite. Several beds are strongly oolitic; others are a fine conglomerate or breccia. The member also contains a few beds of green shale as much as 5 inches thick, domes of Stromatocerium, several scour surfaces with a relief of 2-8 inches, and, in one locality, a thin bentonite near the base. The shale beds are persistent from Calhoun County, Illinois, to Ste. Genevieve County, Missouri, but elsewhere the unit is dominantly a relatively pure limestone containing oolite beds. In the northern outcrop area the Brickeys is relatively pure but not oolitic.
Core(s)
Photograph(s)
Contacts
Well log characteristics
Fossils
The Brickeys Member contains domes of Stomatocerium.
Age and correlation
Environments of deposition
Economic importance
Remarks
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
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