 The late Mississippian Mauch Chunk Formation is formed with grayish-red shale, siltstone, sandstone, and conglomerate.The third is the early Pennsylvanian Pottsville Formation, which is a gray conglomerate that may contain sandstone, siltstone, and shale, as well as anthracite coal.The park is at an elevation of atop the Allegheny Plateau, just west of the Allegheny Front, a steep escarpment which rises in , and marks the transition between the Ridge-and-Valley Appalachians to the east and the Allegheny Plateau to the west.