Re: Antarctic crater

[Jeff Hecht <jeff@jeffhecht.com>]

Caution is appropriate, at the very least. Most stories seem based on the press 
release. The only constraints on the date are that the "crater" has to be older 
than a 100-million-year old rift which split it, and must be younger than the 
Precambrian because (the author claims) craters older than the Cambrian don't 
have gravity anomalies. 
http://www.newscientistspace.com/article/dn9268-giant-crater-may-lie-under-antarctic-ice.html

Geologists quoted by Nature 
http://www.nature.com/news/2006/060529/full/060529-11.html are not even 
convinced the structure is a crater. -- Jeff hecht

At 10:54 AM -0700 6/2/06, Richard and Jo Cowen wrote:
>OK, what's this about? First, it's science by poster session and press release 
>(this one's from Ohio State). The research group found in a gravity survey a 
>giant crater in the rock floor a mile under the Antarctic ice sheet. It's 300 
>miles across, apparently, which puts it into the mega-impact category, larger 
>than Chicxulub. The rest is SPECULATION, because we have no data from the 
>rocks. The researchers claim a connection with the Permo-Triassic impact. I 
>wouldn't be surprised, but the evidence for the connection is just not there, 
>even though a large part of the press release is devoted to it.
>
>Cheers
>
>Richard Cowen

-- 
Jeff Hecht, science & technology writer
jeff@jeffhecht.com  http://www.jhecht.net
Boston Correspondent: New Scientist magazine
525 Auburn St., Auburndale, MA 02466 USA
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