Age:

Silurian

Type designation:

Type locality: The Louisville Limestone was named by Foerste (1897, p. 218, 232) for about 60 ft (18 m) of light-colored to medium brown fine-grained thick-bedded argillaceous limestone and dolomitic limestone exposed in and just east of Louisville, Jefferson County, Kentucky, where many good exposures remain, including in road cuts along the interstate highway system (Shaver, 1970; Droste and Shaver, 1986).

History of usage:

Droste and Shaver (1986) noted that from the time of its first introduction, the name “Louisville” was applied in many Indiana reports to rocks in the southeastern Indiana outcrop area that had been considered to be the top part of the Niagara Group, which was true, considering that the Devonian truncation of older rocks extends well down in the Silurian section in that area.

Droste and Shaver (1986) stated that the name was also applied at an early time in northern Indiana (see Cumings, 1922, p. 455-456) but with great confusion, as much of the application was to rocks considerably younger than the Louisville and as the actual Louisville extension northward was often mislabeled as the younger Liston Creek Limestone because of the commonality of chert in these two different units. The correct application in northern Indiana began with John B. Patton in 1954 as recorded by Shaver and others (1961, p. 15, see also p. 13) and as furthered by Pinsak and Shaver (1964, p. 31-33). Becker (1974, p. 20) established definitive use of the name in the Illinois Basin part of southwestern Indiana (Droste and Shaver, 1986).

Droste and Shaver (1982, p. 11) recommended that the use of the name “Louisville” be dropped in northern Indiana and the pertinent rocks be assigned as an upper, unnamed member of the then-new Pleasant Mills Formation. Later, Droste and Shaver (1986) noted that the abandonment of "Louisville" in this area proved to be unsatisfactory, as the name has been used even in adjacent Ohio (Griest and Shaver, 1982, p. 377 and 380), and the term "Louisville-equivalent rocks" has been appearing in northern Indiana-based reports (for example, Ault and Carr, 1983, and Shaver and Sunderman, 1983). For these reasons, Droste and Shaver (1986) reintroduced the term "Louisville" to northern Indiana use as the Louisville Member of the Pleasant Mills Formation.

Droste and Shaver (1986) noted that the rocks recognized as the Louisville include the New Corydon Limestone type section of Cumings and Shrock (1928, p. 116) as shown by Droste and Shaver (1976, p. 19).

Description:

Becker (1974, p. 20) noted that in the subsurface of southern Indiana the Louisville Limestone is characteristically limestone and dolomitic limestone that is light olive to light gray (5 Y 6/1 to N 7), fine to medium grained, and in places shaly and cherty.

The Louisville normally ranges between 40 and 75 ft (12 and 23 m) in thickness, and the thicker sections are westward and northward (Droste and Shaver, 1986). Near the Fort Wayne Bank, nonreefy to somewhat reefy Louisville rocks are as thick as 145 ft (49 m) (Droste and Shaver, 1982, p. 38).

Distribution: Droste and Shaver, (1986) reported that the type-Louisville lithology is present in much of the southern Indiana outcrop area along the west flank of the Cincinnati Arch and in the southwestern subsurface area. The argillaceous facies, particularly in the lower part, extends well northward into the area of application of the name, but farther north and northwestward clastic and calcareous contents decrease, so that these rocks become fairly pure dolomite in northern Indiana (Droste and Shaver, 1986). Chert is common, both in the southwestern subsurface and in the area of outcrop in eastern northern Indiana. The Louisville has a reef facies and this facies is present in a great many pinnacle or patch reefs, southwestern to northern Indiana, and in a lower part of the barrierlike, Michigan Basin-fringing Fort Wayne Bank (Droste and Shaver, 1986).

Although reeflike rocks, bearing stromatoporoids and many tabulate and rugose corals, are present in the southeastern outcrop area, true reefs, complete with topographic relief, are not known in this area (Droste and Shaver, 1986).

Boundaries:

Droste and Shaver (1986) state that Louisville rocks in Indiana are underlain conformably nearly everywhere by the Waldron Shale (Waldron Formation, Waldron Member) and with a conspicuous transitional zone in some places that involves terrigenous clastic sediments well up into the otherwise rather pure carbonate rocks. In far western counties, however, the Louisville lies directly, but conformably, on Salamonie rocks because so few of the Waldron type of sediments are present in that area that Waldron recognition becomes impractical (Droste and Shaver, 1986).

The Louisville is overlain conformably nearly everywhere in its area of Indiana recognition by the Mississinewa Shale Member of the Wabash Formation or, simply, by cherty to pure carbonate rocks of the Wabash where the Mississinewa type lithology is absent (Droste and Shaver, 1986). This contact also involves transitional rocks and as a classificatory procedure the contact is placed at the very bottom of the transitional lithology (Rexroad, Noland, and Pollock, 1978, p. 2). Along part of the area of southeastern Indiana outcrop, the pre-Middle Devonian unconformity overlaps the Mississinewa Shale Member (Silurian), so that rocks of the Muscatatuck Group rest directly on the Louisville (Droste and Shaver, 1986).

The Louisville Limestone, classified at formation rank, has a northern and northwestern vertical cutoff boundary with the Pleasant Mills Formation along a line defined by the southernmost and southwestwardmost limit of the Limberlost Dolomite Member (Pleasant Mills Formation, Salina Group) (Droste and Shaver, 1986). Northward and eastward of this Limberlost limit, the Louisville Member (Pleasant Mills Formation) extends approximately to a line extending from central LaPorte County to central Allen County, that is, to positions along the bottom part of the Fort Wayne Bank (Droste and Shaver, 1982, figs. 5-7). Farther north the Louisville Member mostly cannot be separated from the underlying Pleasant Mills rocks because of northward loss of Waldron recognition (Droste and Shaver, 1986). The Louisville Limestone also has a defined vertical cutoff relationship southwestward with the upper part of the St. Clair Limestone (Becker, 1974, p. 11, fig. 9, and pl. 2).

Correlations:

As already noted, the Louisville Limestone correlates with upper Pleasant Mills rocks of northern Indiana (named in part as the Louisville Member) and with upper St. Clair rocks in the Illinois Basin. In the latter area, probably time-equivalent rocks are also present in the lower part of the Moccasin Springs Formation; this is due to an apparent time- transgressive relationship along the St. Clair-Moccasin Springs boundary (Droste and Shaver, 1986).

The name “Louisville” is used southward across western Kentucky, but the extension of this unit in central southern Kentucky and adjacent Tennessee is called the Lego Limestone. Louisville equivalents are widely recognizable in the Great Lakes area, including northeastern Illinois, eastern Wisconsin, the Michigan Basin, western Ontario and adjacent New York, and Ohio (Droste and Shaver, 1986). Droste and Shaver (1986) noted that partial equivalencies apply to the Racine Formation, the A unit (Salina Group), the Guelph Dolomite, and the Lockport Group.

Louisville rocks coincide closely with the Zone of Rhipidium in the Silurian pentamerid brachiopod zonation (Berry and Boucot, 1970; Shaver and others, 1971; Indiana University Paleontology Seminar, 1976; Droste and Shaver, 1977 and 1985; and Shaver and Sunderman, 1983). Conodont investigations of the southern facies of the Louisville (Rexroad, Noland, and Pollock, 1978) show that it has close affinities with the Kockella variabiIus Zone. These guide fossils are considered to record a late Wenlockian to early Ludlovian age (late Niagaran) (Droste and Shaver, 1986).

Economic Importance:

Industrial Minerals: Crushed stone products from the Louisville Limestone, Member (Silurian) include the following: aglime, base materials, class A stone, chemical uses, crushed and sized limestone, crushed stone, dolomite, dolomite limestone, fill materials, high-calcium limestone, hot and cold mix asphalt, pugmill material, riprap, and manufactured sand from quarries in Adams, Allen, Bartholomew, Blackford, Clark, Delaware, Grant, Hamilton, Huntington, Madison, Scott, Shelby, Wabash, and Wells Counties (Shaffer, 2016).

Regional Indiana usage:

Illinois Basin (COSUNA 11)
Supergroup: none
Group: none
Formation: Louisville Limestone
Illinois Basin Margin (COSUNA 12)
Supergroup: none
Group: Salina Group
Formation: Pleasant Mills Formation
Member: Louisville Member
Illinois Basin Margin (COSUNA 12)
Supergroup: none
Group: none
Formation: Louisville Limestone
Cincinnati Arch (COSUNA 13)
Supergroup: none
Group: none
Formation: Louisville Limestone
Cincinnati Arch (COSUNA 13)
Supergroup: none
Group: Salina Group
Formation: Pleasant Mills Formation
Member: Louisville Member
Kankakee Arch (COSUNA 14)
Supergroup: none
Group: none
Formation: Louisville Limestone
Kankakee Arch (COSUNA 14)
Supergroup: none
Group: Salina Group
Formation: Pleasant Mills Formation
Member: Louisville Member
Michigan Basin (COSUNA 15)
Supergroup: none
Group: Salina Group
Formation: Pleasant Mills Formation
Member: Louisville Member

Misc/Abandoned Names:

New Corydon Limestone

Geologic Map Unit Designation:

Slv

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:

Ault, C. H., and Carr, D. D., 1983, Directory of crushed stone, ground limestone, cement, and lime producers in Indiana: Indiana Geological Survey Directory [unnumbered], 36 p.

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

Berry, W. B. N., and Boucot, A. J., 1970, Correlation of the North American Silurian rocks: Geological Society of America Special Paper 102, 289 p.

Cumings, E. R., 1922, Nomenclature and description of the geological formations of Indiana, in Logan, W. N., Cumings, E. R., Malott, C. A., Visher, S. S., Tucker, W. M., Reeves, J. R., and Legge, H. W., Handbook of Indiana geology: Indiana Department of Conservation Publication No. 21, pt. 4, p. 403–570.

Droste, J. B., and Shaver, R. H., 1977, Synchronization of deposition–Silurian reef-bearing rocks on Wabash Platform with cyclic evaporites of Michigan Basin, in Fisher, J. H., ed., Reefs and evaporites–concepts and depositional models: American Association of Petroleum Geologists Studies in Geology 5, p. 93–109.

Droste, J. B., and Shaver, R. H., 1982, The Salina Group (Middle and Upper Silurian) of Indiana: Indiana Geological Survey Special Report 24, 41 p.

Droste, J. B., and Shaver, R. H., 1985, Comparative stratigraphic framework for Silurian reefs–Michigan Basin to the surrounding platforms, in Cercone, K. R., ed., Symposium on the Silurian and Ordovician of the Michigan Basin: Michigan Basin Geological Society Special Paper 4, p. 73–93.

Droste, J. B., and Shaver, R. H., 1986, Louisville 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. 83–84.

Foerste, A. F., 1897, A report on the geology of the Middle and Upper Silurian rocks of Clark, Jefferson, Ripley, Jennings, and southern Decatur Counties, Indiana: Indiana Department of Geology and Natural Resources Annual Report 21, p. 213–288.

Griest, S. D., and Shaver, R. H., 1982, Geometric and paleoecologic analysis of Silurian reefs near Celina, Ohio: Indiana Academy of Science Proceedings, v. 91, p. 373–390.

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.

Indiana University Paleontology Seminar, 1976, Constitution, growth, and significance of the Silurian reef complex at Rockford, Ohio: American Association of Petroleum Geologists Bulletin, v. 60, p. 428–451.

Pinsak, A. P., and Shaver, R. H., 1964, The Silurian formations of northern Indiana: Indiana Geological Survey Bulletin 32, 87 p.

Rexroad, C. B., Noland, A. V., and Pollock, C. A., 1978, Conodonts from the Louisville Limestone and the Wabash Formation (Silurian) in Clark County, Indiana, and Jefferson County, Kentucky: Indiana Geological Survey Special Report 16, 15 p.

Shaffer, K. R., compiler, 2016, Directory of industrial mineral producers in Indiana: Indiana Geological Survey Directory 11-2016, 287 p.

Shaver, R. H., 1970, Louisville 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. 97–99.

Shaver, R. H., and Sunderman, J. A., 1983, Silurian reef and interreef strata as responses to a cyclical succession of environments, southern Great Lakes area (Field Trip 12), 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. 141–196.

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.

Shaver, R. H., Doheny, E. J., Droste, J. B., Lazor, J. D., Orr, R. W., Pollock, C. A., and Rexroad, C. B., 1971, Silurian and Middle Devonian stratigraphy of the Michigan Basin–a view from the southwest flank, in Forsyth, J. L., Geology of the Lake Erie islands and adjacent shores: Michigan Basin Geological Society Guidebook, p. 37–59.

Shaver, R. H., with contributions by Gray, H. H., Pinsak, A. P., Sunderman, J. A., Thornbury, W. D., and Wayne, W. J., 1961, Stratigraphy of the Silurian rocks of northern Indiana: Indiana Geological Survey Field Conference Guidebook 10, 62 p.