Pennsylvanian System

Type locality and identification problem: The name Bucktown Coal Member (Dugger Formation) was proposed by Wier (1965) in an unpublished manuscript and was first published by Burger and Wier (1970), who also designated a type section in sec. 1, T. 6 N., R. 8 W., near Bucktown in Sullivan County, Ind.

The identification of this coal and the underlying unnamed coal has been the source of some confusion. Ashley (1899, p. 91), although giving no specific section, designated coalbeds above Coal V (now the Springfield Coal Member) and below Coal VI (Hymera Coal Member) as Coal Va and Coal Vb. Logan (1922, p. 627) recognized two thin beds of coal above the Springfield Coal Member but said that "the upper coal is generally thicker and is designated as Coal Va." Wier (1951) and Kottlowski (1954) did not find the lower coal in the area of the Linton and Dugger Quadrangles, so the upper coal was called Coal Va. Wier (1953) and Wier and Stanley (1953) then recognized Coal Va as the lower coal, which lies between the Alum Cave and Antioch Limestone Members, and Coal Vb as the upper coal, which lies above the Antioch Limestone Member. Wier (1965) stated that this lower coal could be recognized in a few exposures as a separate and distinct unit, but he did not name it because of lack of information on its distribution.

Description: The Bucktown coal ranges from 0.1 to 4.0 feet (0.03 to 1.2 m) and averages 1.2 feet (0.4 m) in thickness. In places it contains a shale parting as much as 11 feet (3.4 m) thick (Friedman, 1961). The coal lies stratigraphically 10 to 67 feet (3 to 20 m) above the Springfield Coal Member of the Petersburg Formation and is generally overlain by a dark-gray shale that contains sideritic bands. In Vermilion and Vigo Counties this shale also contains numerous shells of the conchostracan Leaia tricarinata.

Correlation: Although he did not use the name Bucktown Coal Member, Powell (1968) extended recognition of Coal Vb into Vermillion County, Ind.