English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

The Wedington sandstone member of the Fayetteville shale has yielded fragmentary remains of fossil plants at several localities in the Winslow quadrangle, Arkansas. These forms, though many of them are indifferently preserved, are extremely significant in that they represent the first Mississippian land flora to be reported in the Midcontinent region. The age of the beds containing the flora is established by invertebrates, as well as by plants, to be early upper or middle Chester. The flora is related to that of the Chester group of the Eastern Interior basin and to beds of Chester age in the Appalachian trough through certain of its filicinean, calamarian, and lycopodiaceous forms. Likewise it is similar, in certain features, to standard lower Carboniferous floras of Europe. The Mississippian aspect of the flora is modified somewhat by the presence of a lower Pottsville or Namurian element, pointing to upper Chester age. This flora, however, contains no forms in common with the large assemblage of plants described by Lesquereux from the Bloyd shale (middle Pottsville) of the same region. It is suggested that the plants grew in an environment not entirely favorable to the development of large size. The climate was probably marked by a seasonal deficiency of rainfall. The flora, as it is now known, includes 35 species. It contains representatives of the Filicales, the Lycopodiales, the Equisetales, the Sphenophyllales, and the Pteridospermae. STRATIGRAPHY AND DISTRIBUTION OF THE PLANTBEARING BEDS "Wedington sandstone" is the name given by Adams 2 to a sandstone in the upper part of the Fayetteville shale, a formation of upper Mississippian (Chester) age in northwestern Arkansas and eastern Oklahoma. It is classified as a member of the Fayetteville shale, though on account of frequency of repetition, it is often casually mentioned in this paper as the Wedington sandstone. The type locality of the sandstone is Wedington Mountain, in northern Washington County, Ark., in the southwest corner of the Fayetteville quadrangle.3 The sequence of the beds in the Winslow quadrangle,4 immediately adjacent on the south, from which the plant material has been obtained, is briefly summarized as follows: 1 This report was essentially completed by Dr. White before his death, Feb. 7, 1935. The additions and corrections which have since been made are small editorial modifications. 2 Adams, G. I., Zinc and lead deposits of northern Arkansas: IT. S. Geol. Survey Prof. Paper 24, p. 27,1904. 3 Adams, G. I., and Ulrich, E. O., IT. S. Geol. Survey Geol. Atlas, Fayetteville folio (no. 119), p. 4, 1905. 1 Purdue, A. H., TJ. S. Geol. Survey Geol. Atlas, Winslow folio (no. 154), 1916. Sequence of beds in Winslow quadrangle, Arkansas

Fossil flora of the Wedington sandstone member of the Fayetteville shale