U.S. Geological Survey Home AASG Logo USGS HOME CONTACT USGS SEARCH USGS
National Geologic Map Database

Geologic Unit: Buckhorn

Usage:

Buckhorn Member of Dunleith Formation of Galena Group (IL,IA,WI)


Geologic age:

Late Ordovician (Mohawkian; Chatfieldian)


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

Type section (=St. James type section): in quarry at Buena Vista, in NW/4 SW/4 NE/4 sec. 15, T. 28 N., R. 7 E., [approx. Lat. 42 deg. 25 min. 40 sec. N., Long. 89 deg. 40 min. 50 sec. W., Orangeville 7.5-min quadrangle], Stephenson Co., northwestern IL (Templeton and Willman, 1963, Illinois Geol. Survey Bull., no. 89, p. 119; Willman and Buschbach, 1975, Illinois Geol. Survey Bull., no. 95, p. 47-87).
Named from Buckhorn Corners, [Orangeville 7.5-min quadrangle], Stephenson Co., northwestern IL, 2 mi east of type section (Templeton and Willman, 1963, p. 119; Willman and Buschbach, 1975).
Notable exposures in Dixon-Oregon area, northern IL (Templeton and Willman, 1952).


AAPG geologic province:

Iowa shelf
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 conflicts with nomenclatural guidelines (CSN, 1933; ACSN, 1961, 1970; NACSN, 1983, 2005, 2021). May be explained within brackets ([ ]).