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

Geologic Unit: Rock Island

Usage:

Rock Island Coal Member of Tradewater Formation of Raccoon Creek Group (IL*)


Geologic age:

Middle Pennsylvanian (Desmoinesian)*


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

Type locality: southwest bank of Spoon River, in SW/4 SW/4 sec. 23, T. 6 N., R. 1 E., Rock Island Co., western IL (Kosanke and others, 1960).


AAPG geologic province:

Illinois basin*


For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.

Asterisk (*) indicates usage by the U.S. Geological Survey. Other usages by state geological surveys.

"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 ([ ]).