Abstract:
Plant macrofossils are found in shales, ironstone concretions, and sandstones that lie immediately above the Lower Block Coal near Stanley Cemetery in Greene County, Ind. The Lower Block Coal lies at the base of the Brazil Formation, which is the uppermost formation in the Pottsville Series (Pennsylvanian) of Indiana.
The majority of the 1,917 specimens (86 species) collected for this study were obtained from ironstone concretions in the shales. These concretions, which are similar to those found in the Mazon Creek area of Will and Grundy Counties, Ill., are probably the result of bacterial action centered around the plant fragment in clay.
The flora is similar to other Pennsylvanian floras of North America. Such species as
Annularia stellata, Sphenophyllum emarginatum, Neuropteris rarinervis, N. flexuosa,
Alethopteris serli, Calamites suckowi, and Asterotheca oreopteridia indicate that this flora
bears a great resemblance to slightly younger floras, such as the Mazon Creek
assemblage from the Carbondale Formation of Illinois. Such species as Asterophyllites
equisetiformis, Annularia radiata, Sphenophyllum cuneifolium, Lepidodendron
dichotomum, L. wortheni, Palmatopteris furcata, Neuropteris obliqua, Megalopteris
dawsoni, and Sigillariostrobus quadrangularis indicate that the flora is not younger than
early Allegheny and probably is Kanawha (late Pottsville) in age. Because this
assemblange contains both Kanawha taxa and Allegheny entities it is only of general
stratigraphic value.
This flora also is similar to European floras of Late Carboniferous age, and such species as Sigillaria scutellata, Alethopteris davreuxi, A. decurrens, and Neuropteris obliqua indicate an age equivalent to the floras of Westphalian B deposits.