Type locality: The name “Danville” was first used by Bradley (1870, p. 250-252) for a coal near Danville, Illinois (Burger, 1970; Burger and Ault, 1986). Wanless (1956, p. 11) designated the E½ sec. 7, T. 19 N., R. 11 W., Vermilion County, Illinois, as the type locality for this coal, which Kosanke and others (1960, p. 35) recognized as the Danville (No. 7) Coal Member of the Carbondale Formation of Illinois (Burger, 1970; Burger and Ault, 1986).
History of usage:
Extended: Use of this name was extended to Indiana by Wier and Gray (1961). The coals previously known as "Coal VII" (Ashley, 1899, p. 842), the "Millersburg Coal" (Fuller and Ashley, 1902, p. 2), the "Upper Millersburg Coal" (Wier and Stanley, 1953; Wier, 1958), and the "Little Newburg Coal" (Owen, 1839, p. 11; 1856, p. 36; Ashley, 1909, p. 97) were designated the "Danville Coal Member of the Dugger Formation" (Burger, 1970).
The Danville Coal Member is the uppermost member of the Dugger Formation in Indiana and is a bright-banded bituminous coal (Burger and Ault, 1986). The coal contains clay and shale in thin partings, films of clay in vertical joints, and local concentrations of pyrites or marcasite (Burger, 1970; Burger and Ault, 1986).
The Danville coal is erroneously called “Coal VI” by the miners in northern Vigo County and southern Vermillion County (Burger, 1970: Burger and Ault, 1986). The correlations of the Danville Coal Member and the older Hymera Coal Member, which are recognized throughout much of the Indiana coalfield, with two coal beds that are locally called respectively the "Upper" and "Lower Millersburg Coals" in the southern part of Indiana are still tentative (Burger and Ault, 1986). The correlations are uncertain because continuity of the beds is interrupted (Gray, 1979).
Regional Indiana usage:
Illinois Basin (COSUNA 11)
Coal VI, Coal VII, Danville Coal Member (VII), Little Newburg Coal, Millersburg Coal, Upper Millersburg Coal
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.)
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.
Ashley, G. H., 1899, The coal deposits of Indiana: Indiana Department of Geology and Natural Resources Annual Report 23, p. 1–1,573.
Ashley, G. H., 1909, Supplementary report to the report of 1898 on the coal deposits of Indiana: Indiana Department of Geology and Natural Resources Annual Report 33, p. 13–150.
Bradley, F. H., 1870, Geology of Vermilion County, in Geology and paleontology: Illinois State Geological Survey, v. 4, p. 241–265.
Burger, A. M., 1970, Danville Coal Member (VII), 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. 41–42.
Burger, A. M., and Ault, C. H., 1986, Danville 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. 34.
Fuller, M. L., and Ashley, G. H., 1902, Description of the Ditney quadrangle: U.S. Geological Survey Geologic Atlas, Folio 84, 8 p.
Gray, H. H., 1979, The Mississippian and Pennsylvanian (Carboniferous) Systems in the United States—Indiana: U.S. Geological Survey Professional Paper 1110-K, 20 p.
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.
Kosanke, R. M., Simon, J. A., Wanless, H. R., and Willman, H. B., 1960, Classification of the Pennsylvanian strata of Illinois: Illinois State Geological Survey Report of Investigations 214, 84 p.
Owen, D. D., 1839, Second report of a geological survey of Indiana, made in the year 1838, in conformity to an order of the legislature: Indiana Senate Journal for 1838-39, p. 198–241: Indianapolis, Osborn and Willets, 54 p.
Owen, D. D., 1856, Report of the geological survey in Kentucky, made during the years 1854 and 1855: Frankfort, Ky., 416 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.
Wanless, H. R., 1956, Classification of the Pennsylvanian rocks of Illinois as of 1956: Illinois State Geological Survey Circular 217, 14 p.
Wier, C. E., and Gray, H. H., 1961, Geologic map of the Indianapolis 1° x 2° quadrangle, Indiana and Illinois, showing bedrock and unconsolidated deposits: Indiana Geological Survey Regional Geologic Map, Indianapolis Sheet, scale 1:250,000.
For additional information, contact:
Nancy Hasenmueller (firstname.lastname@example.org)Date last revised: November 22, 2016