[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

Re: Theories on the extinction of dinosaurs

TomHopp@aol.com wrote:

> We had a go-round on this list a few months ago on the subject. I think that
> the idea might actually have arisen right here, though by whom it was first
> mooted, I don't recall. Maybe Jim Cunningham.

Wasn't me.  I tend to respond to this stuff, but not initiate it. JimC

> My own thinking is, if the
> impactor was pure comet, and not part or all asteroid, then the hole in the
> ground might be deceptively small.

I speculate that, whether comet or asteroid, the impactor was somewhat smaller
than the 6 mile diameter often postulated, and that it may not have been
traveling at the upper range of probable speeds (all bets are off if it were an
interstellar interloper).  In my mind, I really can't match up the limited 
(continental shelf collapse, boulder sized sediment east of Florida, boulder
sediment in Texas, global tsunamis, plasma damage apparently limited to the
western hemisphere, significant small animal survival, etc., with an explosion 
the 20 teraton range.  If I were a betting man, I'd bet that the total energy 
less than half that.

> Furthermore, even Alvarez seems to neglect
> the hypersonic shock wave in his book,

The shock wave will drop to sonic velocity within the first few thousand miles.

> if I recall right from a scanning of
> the text I did months ago. He was into dust, understandably, since it ties
> into his scientific datum, the iridium layer. Free of any such data-fixation,
> I'm willing to speculate a little. What was that p-chem equation, PV=nRT or
> some such thing? Pressure converts to heat.

Indeed it does.  However,with energies of this order of magnitude,  this 
isn't the only equation operating.