Original paper
Base of the Upper Devonian in the Conodont Zonation
Johnson, J. G.
Newsletters on Stratigraphy Volume 21 Number 1 (1989), p. 11 - 14
published: 8/30/1989
published: 8/30/1989
BibTeX file
RIS bibliography file
ArtNo.: ESP026002101002
Abstract
The base of the Lower asymmetrica Zone has been displaced backward in time as the early evolution of its definer, Ancyrodella rotundiloba, has been made known. Assertions that the base of the zone can remain stable, without redefinition, lack a viable basis such as location in a stratotype.