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

Geologic Unit: Clear Creek

Usage:

Clear Creek Chert (IL*,KY*,MO)
Clear Creek Chert of New Harmony Group (IL,IN)
Clear Creek Formation (IL*,MO)
Clear Creek Limestone (IL*,KY*,MO*)


Geologic age:

Early Devonian*


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

Named from exposures on Clear Creek, Union Co., southwestern IL (Worthen, 1866).


AAPG geologic province:

Illinois 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 ([ ]).