Pg. 89, 204. Jake Creek sandstone of Carbondale group. Thin-bedded fine-grained micaceous sandstone in Liverpool cyclothem. Sandstone only locally present but has maximum thickness of about 18 feet. Occurs above Francis Creek shale and below Oak Grove beds. Age is Pennsylvanian.
Type locality: on Jake Creek, in NE/4 sec. 13, T. 4 N., R. 1 E., Vermont quadrangle, Fulton Co., west-central IL.
Source: US geologic names lexicon (USGS Bull. 1200, p. 1908).
Pg. 35. Jake Creek sandstone member of Carbondale formation of Kewanee group (new). Rank reduced to member status in Carbondale formation. Occurs above Francis Creek shale member and below Lowell coal member. Age is Pennsylvanian. Presentation of new rock-stratigraphic classification of Pennsylvanian strata in Illinois.
Source: US geologic names lexicon (USGS Bull. 1200, p. 1908).
For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.
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