The Eocene/Oligocene boundary event in the deep sea.
Analysis of middle Eocene to early, Oligocene calcareous and siliceous microfossils shows gradual biotic changes with no massive extinction event across the Eocene/Oligocene boundary. Biotic changes in the late Paleogene appear to reflect changing paleoclimatic and paleoceanographic conditions and do not support suggestions of a catastrophic biotic event caused by a bolide impact at the Eocenel Oligocene boundary.
Corliss
B H
BH
Aubry
M P
MP
Berggren
W A
WA
Fenner
J M
JM
Keigwin
L D
LD
Keller
G
G