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National Geologic Map Database

Geologic Unit: Roundtop

Usage:

Roundtop Group (ND)
Roundtop Formation (SD)
Roundtop Member of Hartville Formation (NE,WY)


Geologic age:

Middle Pennsylvanian (Desmoinesian)


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

Roundtop Mountain, in sec. 22, T. 27 N., R. 66 W., Platte Co., WY. Named from Roundtop Mountain (Condra and others, 1940).


AAPG geologic province:

Chadron arch
Denver basin


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 ([ ]).