Evolución paleoambiental del tránsito Eoceno-Oligoceno en el Atlántico sur (Sondeo 1263) basada en foraminíferos bentónicos

Abstract

Quantitative análisis of benthic foraminiferal assemblages at South Atlantic Site 1263 provided information about paleobathymetry and changes in benthic foraminiferal faunas across the Eocene-Oligocene boundary. Benthic foraminifera indicate an upper abyssal depth (~ 2000 m). Changes in relative abundances of Epistominella exigua, Epistominella vitrea, Globocassidulina subglobosa and Nuttallides umbonifera, probably indicate variability in seasonality of export productivity, bottom current intensity and carbonate corrosivity. The transition into glaciation event Oi-1 is characterized by highly seasonal productivity, Oi-1 itself by less variability, probably at fairly active bottom currents