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RE: Ichthyosaurus fossilised in mid-birth ??



--- Ken.Carpenter@dmns.org wrote:

> Since the topic of collapse of wet dunes keeps coming up, I'll
> comment. Anyone who has walked on a beach know that to progress
> rapidly, you walk on the wet sand, not the dry. Why? Because wet sand
> sticks together. It is very difficult to get an instantaneous
> collapse of the lee side of a wet dune. But a dry collapse is more
> frequent as wind piles dry sand up until the angle of repose is
> exceeded. 
    There's a slightly different circumstance which I was alluding to
in a couple of my earlier mailings - where you have water travelling
*through* a sand body. The classic conditions for generating quicksand.
I had a ... memorable ... encounter with some when I was a student
doing my daily jog along the beach when I discovered a patch of
quicksand caused by seawater trapped behind a sand bar and draining
through the sand as the tide went out. Being caught knee-deep in
quicksand, an hour after sundown, in an Aberdeen winter, on a deserted
beach, soaked through and in a biting "sub-tropical" wind, is just what
you need to drive Dr Trewin's tedious sedimentology lectures deep into
your metamorphic petrologist's mind. 
> It then slides down rather suddenly. The model for wet
> collapse was developed in the sand hills of Nebraska, in some rather
> stable dunes. I would argue the analogy is wrong.
>  
> As for the Protoceratops and Velociraptor, there is clear evidence
> that the two were dead at the time of burial 
    Ah... kak interesant! But it still leaves a question of how come
they both end up dead while wrapped in each other.

> (see the PDF of my paper
> describing evidence of predation by theropods - a paper that oddly
> was only briefly mentioned by Farlow and Holtz in their review of
> predation by theropods)

    Opoenming the page as I type. Well trying to. Someone needs to go
and hit the satellite dish again I think. Or your server ... well I'll
get it one of these days, just a bit sad and slower than normal today.
Ah, life. Sheesh, I'd give my right arm to have normal dial-up access
from here, not this glacial junk. Well, a couple of fingers maybe <G>
    You mean this one : Carpenter, K. 1998. Evidence of predatory
behavior by carnivorous dinosaurs. Gaia 15: 135-144. (513 KB) ... 
Yeah, must be. Down-crawling now. Bedtime reading!


-- 
Aidan Karley,
Aberdeen,
Scotland


        
        
                
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