Comet or Asteroid Shower in the Late Eocene?
Roald Tagle1 and
Philippe Claeys2*
The passage of a comet shower ~35 million years ago is generally
advocated to explain the coincidence during Earth's late Eocene
of an unusually high flux of interplanetary dust particles and
the formation of the two largest craters in the Cenozoic, Popigai
and the Chesapeake Bay. However, new platinum-group element
analyses indicate that Popigai was formed by the impact of an
L-chondrite meteorite. Such an asteroidal projectile is difficult
to reconcile with a cometary origin. Perhaps instead the higher
delivery rate of extraterrestrial matter, dust, and large objects
was caused by a major collision in the asteroid belt.
2 Department of Geology, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium.
* To whom correspondence should be addressed. E-mail: phclaeys{at}vub.ac.be
