Type area: The name "Black River Limestone" was proposed by Vanuxem (1842, p. 38-45) for rocks exposed in cliffs along the Black River in Oneida and Lewis Counties, New York (Gray, 1970; Droste, J. B., Patton, J. B., and Rexroad, C. B., 1986).
History of usage:
Revised rank: The original name, Black River Limestone, was used for many years in Indiana (Gutstadt, 1958; Gray, 1970); however, Droste, Abdulkareem, and Patton (1982) assigned the Black River rocks group status and divided the group into the Pecatonica Formation below and the Plattin Formation above (Droste, J. B., Patton, J. B., and Rexroad, C. B., 1986).
The Black River Group consists predominantly of light- to dark-gray and brown lithographic to very finely crystalline limestones (Droste, J. B., Patton, J. B., and Rexroad, C. B., 1986). In northwestern Indiana the Black River rocks are dolostone and very dolomitic limestone. The group ranges in thickness from slightly less than 100 ft (30 m) in northwestern Indiana to more than 500 ft (152 m) in southwestern Indiana (Droste, J. B., Patton, J. B., and Rexroad, C. B., 1986).
The Black River Group generally overlies the Joachim Dolomite, possibly with minor unconformity, and is overlain, possibly with some unconformity, by the Trenton Limestone throughout most of the state (Droste, J. B., Patton, J. B., and Rexroad, C. B., 1986). In that part of Indiana where the Trenton Limestone is not recognized, its lateral equivalents, the Kope Formation and the Lexington Limestone, variably overlie the Black River (Droste, J. B., Patton, J. B., and Rexroad, C. B., 1986). In a few isolated places in eastern Indiana where Ancell rocks are missing because of nondeposition, the Black River Group overlies the Prairie du Chien Group (Ordovician) or the Potosi Dolomite (Cambrian) with major unconformity (Droste and Shaver, 1983, fig. 2; Droste, J. B., Patton, J. B., and Rexroad, C. B., 1986).
The Black River Group of Indiana is equivalent to the Platteville Group of Illinois, the Black River Group of Michigan, most of the Black River Limestone of Ohio, and the upper part of the High Bridge Group of Kentucky (Droste, J. B., Patton, J. B., and Rexroad, C. B., 1986). Conodonts from the upper few feet of the Black River (Plattin Formation) from a core in White County, Indiana, appear to indicate fauna 8 of Sweet, Ethington, and Barnes (1971) (Votaw, 1978); conodonts from the rest of the Plattin Limestone and the Pecatonica Formation represent fauna 7 (Votaw, 1978). This includes a sandy interval at the base of the Black River that is equivalent to the Hennepin Member (Pecatonica Formation) of Illinois but that Votaw referred to the St. Peter Sandstone (Droste, J. B., Patton, J. B., and Rexroad, C. B., 1986).
Regional Indiana usage:
Illinois Basin (COSUNA 11)
Geologic Map Unit Designation:
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.)
Droste, J. B., Patton, J. B., and Rexroad, C. B., 1986, Black River Group, 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. 14-15.
Gray, H. H., 1970, Black River Limestone, 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. 15-16.
Gutschick, R. C., 1983, Geology of the Kentland Dome structurally complex anomaly, northwestern Indiana (Field Trip 15), in Shaver, R. H., and Sunderman, J. A., eds., Field trips in midwestern geology: Bloomington, Indiana, Geological Society of America, Indiana Geological Survey, and Indiana University Department of Geology, v. 1., p. 105-138.
Hansen, W. R., 1991, Suggestions to authors of the reports of the United States Geological Survey (7th ed.): Washington, D.C., U.S. Geological Survey, 289 p.
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.
Sweet, W. C., Ethington, R. L., and Barnes, C. R., 1971, North American Middle and Upper Ordovician conodont faunas: Geological Society of America Memoirs 127, p. 163-193.
Vanuxem, Lardner, 1842, Geology of New York–Pt. 3, Comprising the survey of the third geological district: Albany, W. & A. White & J. Visscher, 306 p.
Votaw, R. B., 1978, Conodonts from a core of the Black River Limestone, subsurface of White County, Indiana: Indiana Academy of Science Proceedings, v. 87, p. 276-281.
For additional information contact:
Nancy Hasenmueller (firstname.lastname@example.org)Date last revised: July 15, 2014