Age:

Devonian

Type designation:

Type section: The altered volcanic ash that was noted by Fettke (1931, p. 8) in the Tioga Gas Field of Pennsylvania was named the Tioga Bentonite by Ebright, Fettke, and Ingham (1949, p. 10) (Droste and Shaver, 1986).

Reference section: Becker (1974, p. 39-43) designated rocks cored at 4,056 ft (1,237 m) in the Superior No. 1 Comm. Braselton well (Indiana Geological Survey Petroleum Database Management System No. 129842), Gibson County, Indiana (sec. 24, T. 2 S., R. 12 W.) as an Indiana reference section (Droste and Shaver, 1986).

Description:

A description of this stratigraphic term is being revised or developed, and is not available at this time.

Regional Indiana usage:

Illinois Basin (COSUNA 11)
Supergroup: none
Group: Muscatatuck Group
Formation: Jeffersonville Limestone
Member: Vernon Fork Member
Bed: Tioga Bentonite Bed
Illinois Basin Margin (COSUNA 12)
Supergroup: none
Group: Muscatatuck Group
Formation: Jeffersonville Limestone
Member: Vernon Fork Member
Bed: Tioga Bentonite Bed
Cincinnati Arch (COSUNA 13)
Supergroup: none
Group: Muscatatuck Group
Formation: Jeffersonville Limestone
Member: Vernon Fork Member
Bed: Tioga Bentonite Bed
Kankakee Arch (COSUNA 14)
Supergroup: none
Group: Muscatatuck Group
Formation: Jeffersonville Limestone
Member: Vernon Fork Member
Bed: Tioga Bentonite Bed
Kankakee Arch (COSUNA 14)
Supergroup: none
Group: Muscatatuck Group
Formation: Detroit River Formation
Member: Cranberry Marsh Member
Bed: Tioga Bentonite Bed
Michigan Basin (COSUNA 15)
Supergroup: none
Group: Muscatatuck Group
Formation: Detroit River Formation
Member: Cranberry Marsh Member
Bed: Tioga Bentonite Bed

Misc/Abandoned Names:

Onondaga Indian Nation Bentonite

Geologic Map Unit Designation:

Djtb

Note: Hansen (1991, p. 52) in Suggestions to authors of the reports of the United States Geological Survey noted that letter symbols for map units are considered to be unique to each geologic map and that adjacent maps do not necessarily need to use the same symbols for the same map unit. Therefore, map unit abbreviations in the Indiana Geologic Names Information System should be regarded simply as recommendations.

COSUNA areas and regional terminology

Names for geologic units vary across Indiana. The Midwestern Basin and Arches Region COSUNA chart (Shaver, 1984) was developed to strategically document such variations in terminology. The geologic map (below left) is derived from this chart and provides an index to the five defined COSUNA regions in Indiana. The regions are generally based on regional bedrock outcrop patterns and major structural features in Indiana. (Click the maps below to view more detailed maps of COSUNA regions and major structural features in Indiana.)

COSUNA areas and numbers that approximate regional bedrock outcrop patterns and major structural features in Indiana.

Major tectonic features that affect bedrock geology in Indiana.

References:

Becker, L. E., 1974, Silurian and Devonian rocks in Indiana southwest of the Cincinnati Arch: Indiana Geological Survey Bulletin 50, 83 p.

Droste, J. B., and Shaver, R. H., 1986, Tioga Bentonite Bed, in Shaver, R. H., Ault, C. H., Burger, A. M., Carr, D. D., Droste, J. B., Eggert, D. L., Gray, H. H., Harper, Denver, Hasenmueller, N. R., Hasenmueller, W. A., Horowitz, A. S., Hutchison, H. C., Keith, B. D., Keller, S. J., Patton, J. B., Rexroad, C. B., and Wier, C. E., Compendium of Paleozoic rock-unit stratigraphy in Indiana–a revision: Indiana Geological Survey Bulletin 59, p. 154–155.

Ebright, J. R., Fettke, C. R., and Ingham, A. I., 1949, East Fork-Wharton gas field, Potter County, Pennsylvania: Pennsylvania Geological Survey Bulletin M30, ser. 4, 43 p.

Fettke, C. R., 1931, Physical characteristics of the Oriskany Sandstone and subsurface studies in the Tioga gas field, Pennsylvania: Pennsylvania Geological Survey Bulletin 1028, ser. 4, 9 p.

Hansen, W. R., 1991, Suggestions to authors of the reports of the United States Geological Survey (7^th ed.): Washington, D.C., U.S. Geological Survey, 289 p.