SV: ..not dinosaurs, but comets ...

[Tommy Tyrberg <tommy.tyrberg@norrkoping.mail.telia.com>]

The trouble with this theory is that only small impactors (like the
Tunguska object) explode in the atmosphere without impacting, while
exterminating megafauna all over North America (not to mention the rest
of the world) would take a really big impact.
A much better way to explain the absence of a crater would be to
postulate an inpact on top of the Laurentide Ice Sheet. You could
probably explain away a fairly large crater that way.

Tommy Tyrberg

-----Ursprungligt meddelande-----
Från: owner-DINOSAUR@usc.edu [mailto:owner-DINOSAUR@usc.edu] För MICHAEL
MURPHY
Skickat: den 3 januari 2009 21:59
Till: Dinosaur@usc.edu
Ämne: Re: ..not dinosaurs, but comets ...

>From the story linked to:

In response to one common criticism of the comet theory - that no
craters have been found from an impact - West said the comet may not
have actually reached Earth, but exploded into fragments somewhere above
the surface.

Where exactly that might have happened is a mystery, but high
concentrations of nanodiamonds at a site in Eastern Michigan suggest the
Great Lakes as a possibility.
----

Last year there was some talk that the "crater" might be an anomalous
deep spot in Lake Superior(?).  Maybe that went nowhere.

M.J.Murphy