[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]
Re: K-T impact theory
At 10:59 PM 5/28/97 -0700, Jonathon Woolf wrote:
>I don't think you understand the full scope of my question. Nuees
>ardente wipe the ground clean. _Everything_ is gone. Trees get
>charcoaled on the spot. Brush is simply vaporized. Animals are
>broiled alive. Seeds are either killed by the heat or buried too
>deeply to germinate. Nothing larger than a gopher survived the Mount
>St. Helens ashblast,
In the *direct* ashfall area. Beyond a few kilometers away in direct line,
and closer off the direct line, there were isolated patches of land
protected by topography from the full effects of the blast. Even fully
grown trees survived in some of these patches. The pattern of destruction
was quite complex, and very uneven.
A similar thing would happen in the case of a large meteoric firestorm.
Possibly on a larger scale - with larger protected patches.
So we are not talking *one* refuge, but rather thousands of tiny little
refuges across the whole of the continent, mostly in mountainous regions.
> and those few animals that did survive the blast
>all died within a couple of years because of lack of food.
Which of course might explain why the larger animals, the dinosaurs and
large pterosaurs and so on died and the smaller, more opportunistic animals
tended to survive.
> Are you
>seriously suggesting that life could recover from a disaster of far
>greater magnitude across all of North America in a few thousand
To the extent that it *did* recover - yes. Remember, for *millions* of
years after there were few, if any, land animals larger than a cat. That
is pretty devastated in my book.
>... An "asteroid winter" of the sort currently
You are behind on the estimates. The best current estimates are a mild
The fact that the impact *did* occur indicates it *could* *not* have been
as destructive as you imagine.
Now, despite my points above, I do not believe that the impact was thr
*sole* cause of the extinctions.
May the peace of God be with you. firstname.lastname@example.org