National Geologic Map Database

Geologic Unit: Peoria


Peoria Silt of Mason Group (IL*)
Peoria Loess (AR,CO*,IL*,IN*,IA*,KS*,KY*,LA,MO,NE*,OH*,WI*)
Peoria Formation (KS,NE)
Peoria Member of Kieler Formation (WI)
Peoria Loess Member of Atherton Formation (IN)


FORMATION STATUS: Morton Tongue (IL*), Todd Valley Member (NE).
MEMBER STATUS: Morton Tongue (IN).

Geologic age:

Quaternary (late Pleistocene)*

Type section, locality, area and/or origin of name:

Named from exposures in vicinity of Peoria, Tazewell Co., IL (Leverett, 1898).
Type section: Tindall School section, in west bluff of Illinois Valley south of Peoria (Hansel and Johnson, 1996).
Principal reference sections (Hansel and Johnson, 1996):
(1) Athens north quarry section, in north highwall of limestone quarry, 5 mi (8 km) northeast of Athens, in SW/4 SE/4 NE/4 sec. 18, T. 18 N., R. 5 W., Mason City SW 7.5-min quadrangle, Menard Co., IL;
(2) Bellefontaine quarry section, in southwest corner of large quarry, in sec. 9, T. 47 N., R. 7 E., Columbia Bottom, MO-IL 7.5-min quadrangle, St. Louis Co., MO;
(3) Cottonwood School section, roadcuts along center east line of sec. 11, T. 18 N., R. 11 W., Clear Lake 7.5-min quadrangle, Cass Co., IL;
(4) Danvers (Rock Creek) section, in cutbank on south side of Rock Creek, in NW/4 NE/4 NW/4 sec. 32, T. 25 N., R. 1 W., Danvers 7.5-min quadrangle, Woodford Co., IL;
(5) Farm Creek section, on south side of Farm Creek, in NE/4 SW/4 SE/4 sec. 30, T. 26 N., R. 3 W., Washington 7.5-min quadrangle, Tazewell Co., IL;
(6) Gardena section, exposed in stream bank 99 ft (30 m) west (downstream) of Toledo, Peoria, and Western RR bridge, in NW/4 SW/4 NW/4 sec. 32, T. 26 N., R. 3 W., Washington 7.5-min quadrangle, Tazewell Co., IL.
Reference sections (member status) =type sections of Kieler Formation and Wyalusing Member of Kieler Formation; see entries under Kieler and Wyalusing (Syverson and others, 2011, Wisconsin Geol. Nat. Hist. Survey Tech. Rpt., no. 1, p. 157+).

AAPG geologic province:

Arkla basin
Cincinnati arch*
Desha basin
Illinois basin*
Iowa shelf*
Salina basin*
Upper Mississippi embayment*
Wisconsin arch*

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 does not conform with nomenclatural guidelines (CSN, 1933; ACSN, 1961, 1970; NACSN, 1983, 2005). This may be explained within brackets ([ ]).