[Rockhounds] Another extinction impact-13 KYA

[Tim Fisher]

There was a very critical report about the theory that was briefly mentioned
on a Discovery Channel program recently. The author questioned the
"hexagonal diamond" theory and essentially called it hocus pocus.

-----Original Message-----
From: rockhounds-bounces at lists.drizzle.com
[mailto:rockhounds-bounces at lists.drizzle.com] On Behalf Of Dora Smith
Sent: Friday, January 02, 2009 9:43 AM
To: Rockhounds at drizzle.com: A mailing list for rock and gem collectors
Subject: Re: [Rockhounds] Another extinction impact-13 KYA

Thanks.  The article is a red herring.   It has been satisfactorily 
demonstrated that the abrupt cooling was the result of the massive 
outpouring of melted ice into the northern Atlantic when an ice bridge that 
had held it back melted.   The massive influx of cold fresh water shut down 
the currents in the North Atlantic that moderate climate and caused the ice 
age to return.   Something similar may have occurred when glaciers in the 
northern Atlantic melted during the medieval warm period, which may have 
helped lead to the little ice age.   Seems that a change in air currents 
over the Pacific, the southwestern U.S., and the northern Atlantic led to 
one development which was limited to the northern Atlantic and Europe, with 
no significant climate change elsewhere, and fluctuations in solar activity 
may have contributed to the latter.

It does often happen in geology that more than one thing contributes to a 
climatological event or mass extinction, as for instance the Deccan Trap 
eruptions and meteor strike that ended the Cretaceous.

It is recognized that whatever caused it, the return of the ice age was 
especially severe in North America, apparently more severe than the rest of 
that ice age.  It turned the southeastern U.S. into a desert, and caused 
plant and animal species, including kinds of trees, to go extinct all over 
the North American continent.   Humans must have lived in the southeastern 
U.S. as the genetic and archeological record demonstrate that they got there

from Europe by crossing the Atlantic when it froze during the winter, but 
those people or what remained of them were driven westward and now their 
genetic signature is found in the central and western U.S.

I'll be watching to see what you all decide about those hexagonal diamonds; 
that is a critical point.

The article itself lacks internal logic, never mind an understanding of 
science.   First meteors caused the cooling, then we have a discussion that 
it is accepted that melting ice pouring into the north atlantic caused it. 
First we have diamonds encased in carbon, and then suddenly it's hexagonal 
diamonds.   I'd start with checking to see if the researchers themselves 
actually make that claim.

Yours,
Dora Smith
Austin, TX
tiggernut24 at yahoo.com
----- Original Message ----- 
From: "J Bryan Kramer" <codeburner at gmail.com>
To: "Rockhounds at drizzle.com: A mailing list for rock and gem collectors" 
<rockhounds at lists.drizzle.com>
Sent: Friday, January 02, 2009 9:11 AM
Subject: [Rockhounds] Another extinction impact-13 KYA


<
http://www.nytimes.com/2009/01/02/science/02impact.html?_r=2&partner=rss&emc
=rss&pagewanted=all
>

I never heard of hexagonal diamonds, isn't that graphite's crystal
structure?

BK
-- 

""It often seems to me that the night is much more alive and richly colored
than the day."

                      Vincent van Gogh
J Bryan Krämer
North Florida, USA
photos at:
http://pbase.com/photoburner


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