Re: Fw: RE: EPH - Tom Van Flandern
David Campbell (bivalve@mailserv0.isis.unc.edu)
Tue, 30 Mar 1999 12:07:35 -0400
> The most recent (a relatively small explosion, probably of a Moon-sized body)
>>at 3.2 million years ago corresponds with the Pliocene-Pleistocene boundary,
>>the end of a tropical pole-to-pole climate period, and the onset of the
>>continuing series of glaciation cycles. New evidence in just the last six
>>months from Peter Schultz indicates a major cratering event in Argentina
>>coinciding with that boundary.
That's not the Plio-Pleistocene boundary. It's in the middle of the
Pliocene. The South Pole had been cold for about 30 million years by that
point.
To cause a single crater, there is no need for a planetary explosion.
In the Western Atlantic bivalves, there are two major extinctions, not just
one, in the mid-Pliocene to Pleistocene. They correlate with climatic and
sea-level changes, which in turn are explicable by the consequences of the
closing of the isthmus of Panama.
David C.