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 Tools annual

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 Tools monthly

Global: Zendy Plus monthly

Presents the access of premium content as premium feature

Premium Content

Global: Zendy Plus annual

Global: Zendy Free Plan

The Barnett formation (Mississippian) of the Llano region, Texas, contains two conodont faunal zones. The upper of these two zones is believed to be restricted to that portion of the formation which herein is regarded as being of Meramec and possibly also partly of Chester age; and the lower faunal zone, to that portion of the formation which herein is regarded as being of Osage (Keokuk) age. Rocks assigned to the upper faunal zone are present in all quadrants of the Llano region. In the eastern part of the area, these rocks consist chiefly of olive-gray to yellowish-brown shales that are interbedded with a few thin argillaceous limestones; westward, the above-mentioned rocks merge into limestones, some of which are extremely crinoidal. Conodonts are numerous in most collections, but the faunal assemblage is small as only 10 genera and 18 species have been recognized in 65 collections. Some of these conodonts are present in the lower part of the Stanley shale of Oklahoma and Arkansas, as well as in the Caney shale of Oklahoma. Two new generic names, Geniculatus and Roundya are proposed. P. V. Roundy's conodonts from the Barnett formation have been studied and all of his type specimens have been refigured. Rocks assigned to the lower faunal zone of the Barnett formation are known to be present only in the southwest quadrant of the Llano region. The fauna of this zone has been recognized in 20 collections but has not been described as it is poorly preserved.

Conodonts of the Barnett formation of Texas