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USGS · 70013528

The Eocene/Oligocene boundary event in the deep sea

B.H. Corliss·M.-P. Aubry·W.A. Berggren·J.M. Fenner·L.D. Keigwin·G. Keller
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Abstract

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 Eocene/Oligocene boundary.

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B.H. Corliss, M.-P. Aubry, W.A. Berggren, J.M. Fenner, L.D. Keigwin, G. Keller. 1984. The Eocene/Oligocene boundary event in the deep sea. https://doi.org/10.1126/science.226.4676.806

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