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Nature 285, 309 - 311 (29 May 1980); doi:10.1038/285309a0

The terminal Eocene event: formation of a ring system around the Earth?

John A. O'Keefe

Laboratory for Astronomy and Solar Physics, Goddard Space Flight Center, Greenbelt, Maryland 20771

The most profound climatic event of the Tertiary was the terminal Eocene event at −34 Myr (ref. 1). Botanical data indicate that winters became much more severe, while summer temperatures were little affected. An explanation in terms of a change in the space direction of the Earth's axis is not dynamically acceptable. On the other hand, an ecological disaster of some kind apparently struck the Radiolaria at this time2; the latter event is accurately correlated (to a few tens of thousands of years) with the formation of the greatest known tektite strewn field, the so-called North American strewn field, which has recently been shown to extend at least half-way around the Earth3. It is suggested here that tektites and microtektites which accompanied this fall, but missed the Earth, organized themselves into a ring system like that of Saturn. The shadow of the rings fell on the winter hemisphere and so produced the observed cooling. The ring lasted between one and several million years.



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