Usage:
Garfield Formation (SD)
(Locally called "Iron Dike" because of iron content and long dike-like outcrops.)
Geologic age:
Precambrian
Type section, locality, area and/or origin of name:
Origin of name not stated, but occurs in Lead district, Lawrence Co., southwestern SD (Hosted and Wright, 1923).
AAPG geologic province:
Midcontinent region
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 ([ ]).