Pennsylvanian System

Type area: The name Dicksburg Hills Sandstone was given by Malott (1948, p. 131, 137-138) to exposures in the Dicksburg Hills in the SW¼ sec. 18, T. 1 N., R. 10 W., southern Knox County, Ind. Wier (1961, 1965) reduced the rank of this sandstone to member and included the unit in the Patoka Formation.

Description and correlation: The Dicksburg Hills Sandstone Member is a massive fine- to coarse-grained crossbedded sandstone containing quartz and clay pebbles. The sandstone is 50 feet (15 m) thick at Dicksburg Hills and more than 80 feet (24 m) thick in northwestern Posey County and southwestern Gibson County. It is exposed from Vanderburgh County to Vigo County and has been called the Murphys Bluff Formation (Malott, 1937, p. 277) in Clark County, Ill., and Sullivan County, Ind. In southern Indiana it is the upper part of the Inglefield Sandstone of Fuller and Clapp (1904). The member is not as prominent west of its outcrop as is the underlying Inglefield Sandstone Member of the Patoka Formation.