The Summit 7.5-minute quadrangle is located south of Louisville and west of Elizabethtown along the boundary between Hardin and Grayson Counties and within the Mississippian Plateau physiographic region (McDowell, 1986). Topography is characterized by the low relief Pennyroyal region that sits at elevations between 560 to 650 ft above sea level, the low relief Mammoth Cave plateau at elevations between 750 to 900 ft, and the steep Dripping Springs escarpment that separates the two plains. Moore (1964) mapped the bedrock geology of the quadrangle, which was later digitized by Conley (2002). Mississippian bedrock is exposed throughout the quadrangle and is cut by several vertical faults. The St. Louis Limestone and overlying Ste. Genevieve Limestone underlie the Pennyroyal region and are the oldest bedrock units in the quadrangle. The Beaver Bend and Paoli Limestones, Sample Sandstone, Reelsville Limestone, and Beech Creek Limestone Member of the Golconda Formation are exposed along the Dripping Springs escarpment. The Mammoth Cave plateau region is underlain by the Big Clifty Sandstone and, locally, Haney Limestone Members of the Golconda Formation east of the Summit Fault, and Hardinsburg Sandstone west of the fault. Previously mapped surficial deposits include minor areas of alluvium in tributaries across the Summit quadrangle, and areas of “slumped sandstone” (colluvium) in the Pennyroyal region (Moore, 1964)
