Raccoon Creek Group

Raccoon Creek Group
Stratigraphic range: Carboniferous
Type	Group
Sub-units	Brazil Formation Caseyville Formation Mansfield Formation Tradewater Formation Staunton Formation
Location
Region	Indiana
Country	United States

Illinois Basin Pennsylvanian stratigraphy

The Raccoon Creek Group is a geologic group in Indiana. It preserves fossils dating back to the Carboniferous period.

Stratigraphy

Brazil Formation

The Brazil Formation is a geologic formation in Indiana consisting of shale, sandstone, clay, and coal. It preserves fossils dating back to the Carboniferous period

Description

The Brazil Formation was named in 1902 for the city of Brazil, located in Clay County, Indiana. It originally included rocks between the bottom of the Petersburg Coal and the top of the Mansfield Sandstone. In 1922, a new survey resulted in restrictions to include only rocks between the Lower Block Coal Member and what was at the time called Coal II. In 1976, it was amended again to include rocks between the upper part of Minshall Coal Member and the lower part of Lower Block Coal Member.

The formation is made up of shale, sandstone, clay, and coal. Thickness is measured between 40 and 90 feet.[1]

Caseyville Formation

The Caseyville Formation is a geologic formation in Kentucky. It preserves fossils dating back to the Carboniferous period.

Mansfield Formation

The Mansfield Formation is a geologic formation in Indiana. It preserves fossils dating back to the Carboniferous period.

Tradewater Formation

The Tradewater Formation is a geologic formation in Kentucky. It preserves fossils dating back to the Carboniferous period .

Staunton Formation

The Staunton Formation is a geologic formation in Indiana [2] consisting of sandstone, shale, and coalbeds.[3][4]

Description

The formation was named by E. R. Cumings to refer to the exposed rocks found near Staunton, Clay County. Later surveys resulted in the inclusion of the Perth Limestone Member into the Staunton Formation, having previously belonged to the Brazil Formation.

The Staunton Formation is made up of sandstone and shale (75 to 150 feet), and coalbeds (up to 8).[3]

References

1. Hutchison, Harold C. "Brazil Formation". Indiana Geological and Water Survey. University of Indiana Bloomington. Retrieved 11 October 2021.
2. Generalized Stratigraphic Column of Indiana Bedrock
3. "Indiana Geological & Water Survey". Indiana University Bloomington. Retrieved 8 October 2021.
4. Keroher, Grace C. (1966). Lexicon of Geologic Names of the United States for 1936-1960. .S. Government Printing Office.