Late Eocene to Early Miocene diatoms from the southwest Atlantic.

Abstract

Presents the stratigraphic distribution of 154 diatom species in a composite upper Eocene to lower Miocene section recovered in cores from Holes 511 and 513 A. The section is divided into 12 biostratigraphic zones based on the highest and lowest occurrences of 11 species. Abundance curves for several diatom species in the vicinity of the Eocene/Oligocene and Oligocene/Miocene boundaries are presented; they suggest that abundance changes may have utility as stratigraphic tools, at least on a local scale. Taxonomic notes on all species studied are presented and eight new species are described. -Authors