Type area: The name "St. Louis Limestone" was first used by Engelmann (1847, p. 119-120) with reference to extensive exposures of limestone near St. Louis, Missouri (Carr, 1986).
History of usage:
Present use stems from E. O. Ulrich's suggestion (Buckley and Buehler, 1904, p. 109-110) of restricting the St. Louis Limestone to the limestone above the Spergen Limestone (now called the Salem Limestone) and below the Ste. Genevieve Limestone (Smith, 1970; Carr, 1986).
The St. Louis Limestone in Indiana can be divided into two parts on the basis of lithology (Pinsak, 1957, p. 23-24). The upper St. Louis, which is the upper one-eighth to one-third of the formation, consists mainly of thin beds of medium- to dark-gray-brown micritic, pelletal, and skeletal limestone and very thin beds of medium-gray shale (Carr, Leininger, and Golde, 1978, p. 79). Nodules and thin discontinuous beds of mottled light- and dark-gray dense chert are generally abundant in the upper 25 to 90 ft (8 to 27 m) of the unit; thin-bedded silty dolostone is as much as 20 percent of the total in places (Carr, 1986). The lower St. Louis on outcrop consists mainly of pellet-micritic limestone, calcareous shale, and silty dolostone (Carr, 1986).
The St. Louis conformably overlies the Salem Limestone and underlies Lost River Chert Bed of Fredonia Member of Ste. Genevieve Limestone (Droste and Carpenter, 1990).
By means of the corals Lithostrotion proliferum, Lithostrotionella castelnaui, and L. hemisphaerica, the St. Louis Limestone of Indiana is correlated with the type St. Louis (Carr, 1986). The upper part of the formation belongs in the Apatognathus scalenus-Cavusgnathus Assemblage Zone (conodonts), to which the upper part of the type St. Louis has also been assigned (Collinson, Rexroad, and Thompson, 1971).
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.)
Beede, J. W., Jackson, T. F., and Malott, C. A., 1915, Geology of the Bloomington quadrangle: Indiana Department of Geology and Natural Resources Annual Report 39, p. 190-312.
Buckley, E. R., and Buehler, H. A., 1904, Quarrying industry of Missouri: Missouri Bureau of Geology and Mines, 2nd Series, v. 2, 371 p.
Carr, D. D., 1986, St. Louis Limestone, 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. 125-126.
Collinson, Charles, Rexroad, C. B., and Thompson, T. L., 1971, Conodont zonation of the North American Mississippian: Geological Society of America Memoirs 127, p. 353-394.
Engelmann, George, 1847, Remarks on the St. Louis Limestone: American Journal of Science, ser. 2, v. 3, p. 119-120.
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.
Jorgensen, D. B., and Carr, D. D., 1973, Influence of cyclic deposition, structural features, and hydrologic controls on evaporite deposits in the St. Louis Limestone in southwestern Indiana, in Eighth Forum on Geology of Industrial Minerals Proceedings: Iowa Geological Survey Public Information Circular 5, p. 43-65.
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.
Smith, N. M., 1970, Salem 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. 152-155.
For additional information contact:
Nancy Hasenmueller (firstname.lastname@example.org)Date last revised: February 8, 2018