[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

first documented victims of K-T boundary asteroid

_The Chronicle of Higher Education_ for Nov. 3, 1995, pp. A11 & A21,
has an article by Kim A. McDonald entitled "Antarctic Dig Finds
Fossils From Ancient Catastrophe," with the subtitle "Remains
may be first evidence of life killed by an asteroid's impact."

The article features the work of William J. Zinsmeister,
Purdue University geosciences professor, at Seymour Island,
about 30 miles from the northeastern tip of the Antarctic
Peninsula (due south of Argentina)

"His discovery of an extensive bed of fish fossils in Antarctica
precisely at the K-T boundary is certain to give additional
support to the impact theory of extinction."  The bone bed
is immediately above the iridium anomaly.  Zinsmeister is
quoted:  "...these fish may actually represent the first
documented victims.  As someone who has argued against catastrophic
extinction in the past, I now think there is evidence for some
kind of a mass kill at the end of the Cretaceous."  No similar
layers were found above or below this bed in 1600 meters of
rock and sediment.  Zinsmeister is still not persuaded that
the asteroid's impact was responsible for all or even most of
the mass extinctions at the end of the Cretaceous, because
the fossil record at Seymour Island and elsewhere shows many
marine species began disappearing millions of years before the
impact...the extinctions resulted from a conjunction of events.

Dewey M. McLean, professor emeritus of geology at Virginia Tech,
"a leading proponent of the idea that volcanoes were responsible
for the mass extinctions at the K-T boundary," is briefly
quoted.  Walter Alvarez is also quoted, but he is reserving
comments on Zinsmeister's discovery for a scientific publication.

The D-word is mentioned only twice in the article.

        George Pesely
        Associate Professor of History
        Austin Peay State University
        Clarksville, Tennessee 37044