Pennsylvanian System

Type section and use of name: The term Hazelton Bridge Formation was proposed by Malott (1939, p. 114) for 20 to 25 feet (6 to 8 m) of shale and one or two thin coal beds, some black shale, and a thin limestone that were exposed in a road cut south of Hazelton Bridge, which spans the White River in northern Gibson County, Ind. These rocks were included by Wier (1961, 1965) in the Patoka Formation, and the name Hazelton Bridge was given member rank and applied to the thin persistent coal lying below the Vigo Limestone Member. The type section of the coal member is at the east edge of the Dicksburg Hills 1 mile (0.6 km) north of Hazelton Bridge in the NE¼NW¼ sec. 20, T. 1 N., R. 10 W.

Description: The Hazelton Bridge Coal Member of the Patoka Formation varies in lithology from a normal bright-banded coal to smutty streaks of coal in shale. The coal ranges from 0.1 to loft feet (0.1 to Orb m) in thickness, is overlain in most places by 1 to 2 feet (0.1 to 0.6 m) of black shale, and generally lies above an underclay, underclay limestone, or calcareous siltstone.

In a few places another thin coal lies below the Hazelton Bridge Coal Member. In some areas both coals are absent, and sandstone is found in the stratigraphic position of these coals. The Hazelton Bridge member is a prominent coal in Gibson County and in southern Knox County and is the coal lying just below the Vigo Limestone Member in Sullivan County and in southern Vigo County.