Re: Chixulub and K/T boundary

[Stan Friesen <swf@ElSegundoCA.ATTGIS.COM>]

>From: richmond@astro.Princeton.EDU ("Stupendous Man")
 >   I have been told that papers "soon to be released" will claim
 > that a close examination of some of the sediments from drillholes
 > into the Chixulub crater area shows Cretaceous marine layers
 > _on top of_ the impact breccia.  I guess that the layers are dated
 > by forams.

Actually, a preliminary note to this effect has already been
published.  However, that was about a year ago, and I find it
odd that the "full" paper has yet to be published.

Also, a number of other people have expressed considerable
skepticism of these purported results.  In fact I suspect that
the recent sulfur cloud evidence may include data that contradicts
the stratigraphic structure implied above.
 > 
 >   I'm aware that radioisotope studies have shown that Chixulub
 > occurred very close the the accepted K/T age, but, if true, this
 > new result would punch some holes in the impact-extinction 
 > theory.

Not as much as you might think.
The evidence for an impact is still substantial, even *without*
the smoking gun of an impact crater.


Actually, I am pretty much of the same mind as Dr. Holtz on
this.  Climatic change had reduced the overall diversity of
dinosaurs already, and then the double whammy of the Deccan
volcanism and the meteroite impact finished off the last of
the non-avian dinosaurs.

swf@elsegundoca.attgis.com              sarima@netcom.com

The peace of God be with you.