Usage:
Guttenberg Limestone Member of Decorah Formation of Galena Group (IL*,IA*,MN*,WI*)
Guttenberg Dolomite Member of Decorah Formation of Galena Group (IL)
Guttenberg Member of Decorah Formation of Sinnipee Group (WI)
Guttenberg Limestone of Decorah Group (IL*,MO*-notably in St. Louis region)
Subunits:
(alphabetical) --all in IA,IL,WI: Garnavillo Member, Glenhaven Member.
Geologic age:
Late Ordovician (Mohawkian)*
Type section, locality, area and/or origin of name:
Type section: in bluff of Mississippi River just northwest of town of Guttenberg, Clayton Co., northeastern IA (Kay, 1928).
Reference sections in MO (Thompson, 1991):
(1) Kings Lake section, in SE/4 SE/4 NE/4 sec. 26, T. 50 N., R. 2 E., Lincoln Co.;
(2) a quarry 2 mi north of New London, in NE/4 NW/4 sec. 36, T. 56 N., R. 5 W., New London 7.5-min quadrangle, Ralls Co.;
(3) roadcut on MO Highway 61 immediately north of bridge over Spencer Creek, in SE/4 SE/4 sec. 21, T. 55 N., R. 4 W., Hannibal 7.5-min quadrangle, Ralls Co.; and
(4) small quarry off gravel road 1 mi north of Pike-Lincoln Co. line, in SE/4 SE/4 SE/4 sec. 28, T. 52 N., R. 2 W., Eolia 7.5-min quadrangle, Pike Co.
AAPG geologic province:
Illinois basin*
Iowa shelf*
Lincoln anticline*
Ozark uplift*
For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.
Asterisk (*) indicates published by U.S. Geological Survey authors.
"No current usage" (†) implies that a name has been abandoned or has fallen into disuse. Former usage and, if known, replacement name given in parentheses ( ).
Slash (/) indicates name conflicts with nomenclatural guidelines (CSN, 1933; ACSN, 1961, 1970; NACSN, 1983, 2005, 2021). May be explained within brackets ([ ]).