Title:

Asteroid Extinction Hypothesis

Author(s):

Kent, Dennis V.

Date:

1981

Type:

Letters

Department:

Lamont-Doherty Earth Observatory

Volume:

211

Permanent URL:

http://hdl.handle.net/10022/AC:P:11959

Book/Journal Title:

Science

Abstract:

A distinguishing feature of the asteroid impact hypothesis presented by Alvarez et al. (6 June, p. 1095) for the end-of-Cretaceous biotic crisis is that it is based on direct physical evidence: the distribution of iridium in several Cretaceous-Tertiary sedimentary sections. I draw attention to other evidence which suggests that (i) a high Ir concentration may not be uniquely associated with an extraordinary extraterrestrial event and (ii) the impact of a large asteroid in any case is not likely to have had the dire consequences to life on the earth that they propose.

Subject(s):

Geochemistry

DOI:

http://dx.doi.org/10.1126/science.211.4483.648

Item views:

116

Metadata:

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