Report of Investigations--KGS

Surficial Geologic Map of the Millerstown 7.5-Minute Quadrangle, Kentucky

Matthew A. Massey, University of Kentucky
Max Hammond III, University of Kentucky
Antonia E. Bottoms, University of Kentucky
Ann Hislop, University of Kentucky
Michelle McHugh, University of Kentucky
Emily Morris, University of Kentucky

Abstract

The Millerstown 7.5-minute quadrangle is located south of Louisville and southwest of Elizabethtown along the boundaries between Hardin, Grayson, and Hart Counties and within the Mississippian Plateau physiographic region (McDowell, 1986). Topography is characterized by the low relief Pennyroyal plain that sits at altitudes below about 650 ft above sea level, the low relief Mammoth Cave plateau at altitudes above about 650 ft, and steep slopes of and isolated knobs of the incised Dripping Springs escarpment that separates the two plains. Moore (1965) mapped the bedrock geology of the quadrangle, which was later digitized by Johnson (2006). Mississippian bedrock and local areas of Pennsylvanian bedrock are exposed throughout most of the quadrangle, all, of which, are cut by several vertical faults. The Ste. Genevieve Limestone is the oldest lithology and underlies the Pennyroyal region in the northeast and southwest corners of the quadrangle, and locally along the Nolin River. The Beaver Bend Limestone, Mooretown Formation, Paoli Limestone, Sample Sandstone, and Reelsville Limestone stratigraphic sequence underlie most of the remaining Pennyroyal plain and several steep slopes of the Dripping Springs escarpment. The Beech Creek Limestone, Big Clifty Sandstone, and Haney Limestone Members of the Golconda Formation are exposed along the Dripping Springs escarpment the edges of the Mammoth Cave plateau region. Most of the Mammoth Cave plateau is underlain by the Hardinsburg Limestone, and, locally in the southwest corner of the quadrangle, the Glen Dean Limestone, Leitchfield Formation, and Pennsylvanian Caseyville Formation. Previously mapped surficial deposits include minor areas of alluvium in tributaries across the Millerstown quadrangle (Moore, 1964).