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Re: Mesozoic terrain (long)
De Camp was absolutely brilliant; that is to say, Van made some really great
James R. Cunningham wrote:
> Jeffrey Willson wrote:
> > I did not say what dinos "could not do".
> > I believe I was careful to say de Camp "opined" a hypothesis, about which
> > ramifications "seemed" to me to follow.
> > It seems to me that two possibilities which follow from the info I posted
> > are
> > A) de Camp doesn't know beans.
> Hi, JimC here again. The only time I ever thought Sprague didn't know
> beans, was when he told James Gifford I was doing a biography of Robert
> Heinlein (I'm not, and wasn't). The de Camps are absolutely brilliant;
> both of them. I've never caught de Camp in a technical error and am not
> sure he knows how to make one, but that isn't really my point here.
> Over grazing might move a range from year to year, but erosion won't.
> The most rapid erosion I've seen was along the Mississippi River, where
> a strip of bank ten or fifteen yards wide and a couple hundred yards
> long might go in a single splash, but that doesn't happen very often -
> perhaps once or twice a year in unstable areas - once in ten years in
> stable reaches. On the other hand, island formation and bar movements
> can be more rapid. The second most severe erosion in my experience was
> along Tillatoba Creek in north central Mississippi where head cutting
> was lowering the channel bottom about ten feet and the overfall was
> moving upstream a few hundred feet a year. Neither of these events
> would have the least effect on annual range changes, but could easily
> require that new crossing points be found. I like the idea of predator
> concentration at terrain transition points. That sort of thought is
> what I find most fascinating about this list. Thanks.
> > If we mean that the "preferred ranges" were actually "moving" from year to
> > year due to erosion, I'd call this "serious" if not catastrophic.
> This wouldn't happen, except perhaps from severe wind driven 'dust bowl'
> events like the one that caused the 'Oakie' migrations of the 30's, or
> very rare natural dam (or ice dam) collapses that catastrophicly release
> lakes into the downstream channel.
> > (Whats the back-of-the-envelope math on the energy needed to raise a 20,000
> > kilo dinosaur 10 meters?).
> 10*20,000=200,000 kilogram-meters of work. Power required depends on
> how quickly they do it.
> > Jeffrey Willson <email@example.com>
Fight Fugue----remain irrational