- Usage in publication:
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- Trivoli sandstone member
- Modifications:
-
- Revised
- AAPG geologic province:
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- Illinois basin
Summary:
Pg. 37, 38, 49 (table 1), 69, pl. 1. Trivoli sandstone member of Modesto formation (new). Rank reduced to member status in Modesto formation. In southeastern area, occurs above West Franklin limestone member and below Chapel (No. 8) coal member; in southwestern area, occurs above Scottville limestone member and below Chapel (No. 8) coal member; western and northern area occurs above Exline limestone member and below Chapel (No. 8) coal member. Thickness 12 to 38 feet. [Age is Late Pennsylvanian.] Presentation of new rock-stratigraphic classification of Pennsylvanian strata in Illinois. Cyclical classification is retained but is entirely independent of rock-stratigraphic classification.
Source: US geologic names lexicon (USGS Bull. 1200, p. 3959-3960).
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 ([ ]).