Marine organic-walled microfossils at the Cretaceous Tertiary boundary in the Barranco del Gredero (S.E. Spain)

Abstract

Assemblages of marine organic-walled microfossils have been studied in four samples (SM 75 -502, -504, -505, and -506) that represent the Maastrichtian-Danian boundary layers in the Barranco del Gredero (S.E. Spain). No sharp changes can be seen in their composition and the marine organic walled microfossils give no indication here at which level the Cretaceous-Paleocene boundary has to be placed.