Paleontologist sugests that multiple meteor strikes caused KT extinctions

Thread view:

Enable EMail Alerts

Start New Thread

Thread rating:

Danniel Soares - 19 Oct 2006 21:56 GMT

http://www.spaceref.com/news/viewpr.html?pid=21082

Related stuff:

- http://geoweb.princeton.edu/people/faculty/keller/chicxulub.html
- http://www.princeton.edu/pr/pwb/03/0922/
-
http://filebox.vt.edu/artsci/geology/mclean/Dinosaur_Volcano_Extinction/pages/st
udentv.html
- http://www.mantleplumes.org/Deccan.html

Reply to this Message

don kenney - 20 Oct 2006 12:48 GMT

> http://www.spaceref.com/news/viewpr.html?pid=21082
>
[quoted text clipped - 5 lines]
> http://filebox.vt.edu/artsci/geology/mclean/Dinosaur_Volcano_Extinction/pages/st
udentv.html
> - http://www.mantleplumes.org/Deccan.html

Basically, these folks are trying to deal with the problem that the
Chicxulub impact evidence really never has fit that well with the data
for the KT extinction event -- which was apparently somewhat gradual
and quite possibly started several million years before the impact.
Add to that growing doubts about whether the other major extinction
events in history are impact related. I've never found anyone who
explains plausibly, in detail, how an impact such as Chicxulub could
both kill megafauna planetwide and still trigger microfauna, floral and
marine extinctions hundreds of thousands of years later. ... Nor
how/why some megafaunal components like crocodiles, lizards, snakes,
turtles and fish cruised through the extinction event relatively
unscathed.

Not that the Chicxulub impact wasn't involved in the KT extinction.
It'd be a remarkable coincidence if it were not. But we don't really
seem to understand how to put all the pieces -- Chichxulub, Deccan
Traps, etc together and create an extinction model that looks plausible.

Reply to this Message

John Harshman - 20 Oct 2006 15:43 GMT

>>http://www.spaceref.com/news/viewpr.html?pid=21082
>>
[quoted text clipped - 10 lines]
> for the KT extinction event -- which was apparently somewhat gradual
> and quite possibly started several million years before the impact.

Are you sure it's not all just Signor-Lipps?

> Add to that growing doubts about whether the other major extinction
> events in history are impact related. I've never found anyone who
[quoted text clipped - 4 lines]
> turtles and fish cruised through the extinction event relatively
> unscathed.

How about this?: Robertson, D. S., M. C. McKenna, O. B. Toon, S. Hope,
and J. A. Lillegraven. 2004. Survival in the first hours of the
Cenozoic. GSA Bulletin 116:760-768.

> Not that the Chicxulub impact wasn't involved in the KT extinction.
> It'd be a remarkable coincidence if it were not. But we don't really
> seem to understand how to put all the pieces -- Chichxulub, Deccan
> Traps, etc together and create an extinction model that looks plausible.

Reply to this Message

Natural Science Forum / Biology / Paleontology / October 2006

Paleontologist sugests that multiple meteor strikes caused KT extinctions