Age:

Pennsylvanian

Type designation:

Type locality: The name “Hazleton Bridge formation” was first used by Malott (1939, p. 114) for 20 to 25 ft (6 to 8 m) of shale, locally containing one or two thin coal beds, some black shale, and a thin limestone, that was exposed in a road cut “near the south end of the White River bridge on U.S. Highway 41 at Hazleton” in northern Gibson County, Indiana.

Type section: Wier (in unpublished manuscripts and 1970, p. 71) noted that the type section of the Hazelton Bridge Coal Member is at the east edge of the Dicksburg Hills 1 mile (1.6 km) north of Hazelton Bridge in the NE¼NW¼ sec. 20, T. 1 N., R. 10 W.

History of usage:

Name revision: Malott (1948, p. 130) referred to the unit as the “Hazelton Bridge formation.”

Revised content and rank: These rocks were included by Wier (in unpublished manuscripts and 1970, p. 71) in the Patoka Formation, and the name "Hazelton Bridge" was given member rank and applied to the thin persistent coal lying below the Vigo Limestone Member.

Description:

The Hazelton Bridge Coal Member of the Patoka Formation varies in lithology from a normal bright-banded coal to smutty streaks of coal in shale (Wier, 1970, 1986). The coal ranges from 0.1 to 1.5 ft (0.1 to 0.5 m) in thickness, is overlain in most places by 1 to 2 ft (0.1 to 0.6 m) of black shale, and generally lies above an underclay, underclay limestone, or calcareous siltstone (Wier, 1970, 1986).

Distribution: In a few places another thin coal lies below the Hazelton Bridge Coal Member (Wier, 1970, 1986). In some areas both coals are absent, and sandstone is found in the stratigraphic position of these coals (Wier, 1970, 1986). The Hazelton Bridge Member is a prominent coal in Gibson County and in southern Knox County and is the coal lying just below the Vigo Limestone Member in Sullivan County and in southern Vigo County (Wier, 1970, 1986).

Regional Indiana usage:

Illinois Basin (COSUNA 11)
Supergroup: none
Group: McLeansboro Group
Formation: Patoka Formation
Member: Hazelton Bridge Coal Member

Misc/Abandoned Names:

None

Geologic Map Unit Designation:

*phb

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:

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.

Malott, C. A., 1939, The Hazleton Bridge Formation of the Upper Pennsylvanian of southwestern Indiana [abs.]: Indiana Academy of Science Proceedings, v. 48, p. 114.

Malott, C. A., 1948, The geology of the Dicksburg Hills, Knox County, Indiana: Indiana Academy of Science Proceedings, v. 57, p. 125–141.

Shaver, R. H., coordinator, 1984, Midwestern basin and arches region–correlation of stratigraphic units in North America (COSUNA): American Association of Petroleum Geologists Correlation Chart Series.

Wier, C. E., 1970, Hazelton Bridge Coal Member, in Shaver, R. H., Burger, A. M., Gates, G. R., Gray, H. H., Hutchison, H. C., Keller, S. J., Patton, J. B., Rexroad, C. B., Smith, N. M., Wayne, W. J., and Wier, C. E., Compendium of rock-unit stratigraphy in Indiana: Indiana Geological Survey Bulletin 43, p. 71.

Wier, C. E., 1986, Hazelton Bridge Coal Member, 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. 59.