1. Map showing bedrock topography and area of occurrence of Madisonville limestone member of Sturgis formation (Upper Pennsylvanian) beneath alluvial deposits of the Smith Mills quadrangle, Henderson and Union counties, Kentucky [cartographic material] Yale Public content 1975. 2013-08-20T14:55:46Z. 2013-08-30T19:15:58Z. Norris, Ronald L. (Ronald Lee). U.S. Geological Survey. English. Public. Kentucky, Henderson County, and Union County.