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Re: Dinosaur trackway questions
Title: Re: Dinosaur trackway
questions
In a message dated
2/14/02 2:26:58 PM Pacific Standard Time, emmar@ldeo.columbia.edu
writes:
<< Coombs' swimming theropods:
there's NO reason to think these are NOT undertracks (I've spent a
considerable amount of time on my hands and knees on that very
surface). (Sorry Rich - IMHO these are NOT 'convincing' swimming
tracks) >>
WHY are they not
'convincing' swimming tracks? WHY no reason? Supposedly swimming
sauropod trackways (manus prints only) have also been dismissed as
undertracks, but I've only heard the dismissals. What have you
discovered in your observations, or must I wait for the paper?
DV
see: Farlow, J. O.,
and P. M. Galton. in press, Dinosaur trackways of Dinosaur State Park,
Rocky Hill, Connecticut. In LeTourneau, P. M. and P. E. Olsen (eds.),
The Great Rift Valleys of Pangea in Eastern North America, vol. 2:
Sedimentology and Paleontology. Columbia University
Press).
I agree with their analysis.....
If you look at deep undertracks, in cases where you have the 3D
recorxd of the track (ie a thick slab that has been sliced through at
diff. layers) you end up, deep down, w/ essentially the same
morpholopgy as you see at Rocky Hill (Coombs 'swimming tracks'). Now,
please enlighten me, if a dino is swimming and its toes grazing the
bottom.....how do the aforementioned toes 'graze' through, in these 3D
cases, 6 inches or more of soft sediment?
----
Emma C. Rainforth
Geosciences Rm. 206E
Lamont-Doherty Earth Observatory
61 Rt. 9W
Palisades
NY 10964-8000
tel. (845) 365-8621
fax (801) 838-4126
emmar@ldeo.columbia.edu
Home page:
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