Geoscience Reference
In-Depth Information
CHAPTER
5
COUNTERATTACK
If you start to take Vienna—take Vienna.
Napoleon Bonaparte
Th e first to offer a detailed attack on the Alvarez theory were not
paleontologists, as might have been expected since they were ap-
parently the most offended, but a geophysicist from Dartmouth
College, Charles Officer (Figure 10), and his colleague, geologist
Charles Drake. Officer had had a distinguished career as a seis-
mologist in industry; Drake was one of the most respected American
geologists, having been president of the American Geophysical
Union from 1984 to 1986, at the height of the controversy, and also
president of the Geological Society of America. They began their
rebuttal with two papers in
Science,
2
which together comprised a
three-part plan of attack:
I
. Falsify the impact theory by showing (a) that the K-T event
took place at different times around the world (and therefore
could not have been the result of an instantaneous global
catastrophe), and (b) that the transition from Cretaceous to
Tertiary fossil species was too gradual to be consistent with an
instantaneous extinction. (I will call these arguments 1 a and
lb, respectively.)
2
. Show that the evidence of iridium anomalies, shocked
minerals, and spherules was far from diagnostic of impact and
often was not even consistent with it (argument 2).
3.
Substitute for impact another process that explains the
evidence at least as well and that does not rely on a
nonuniformitarian deus ex machina (argument 3).
67
