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Re: dinosaur upland faunas?



Pieter.Depuydt (5/29/97; 5:29pm) cited evidence (from Fastovsky et al. 
JVP article) that the La Boca Formation is upland due to evidence of a 
debris flow moving across a surface of considerable relief.  Debris flows 
are common around coastal cliffs, so the cited evidence is not adequate 
to establish that the deposit formed in an upland setting.

When I think of uplands, my fevered brain conjurs up scenes from the 
Colorado Plateau, the Rockies, and Blue Ridge.  Rough, "truly" upland 
terrain may have been relatively more widespread in the Mesozoic than 
now, because higher sea level covered more of the low-lying craton than 
now, including inland regions as well as coastal regions.  I think it is 
correct that no dinosaur remains can be documented as having been derived 
from such truly upland settings, which means we are missing much (most?) 
of the picture.

Likewise, I don't think (OK, I'm bluffing here) the remains of any 
mountain goats that died in Colorado have been found in Missouri.  If the 
skeletal remains are significantly larger than the particles making up 
the siliciclastic sediment fraction, then they haven't come from very far 
away.   They would be highly abraded--rounded, even, within a few miles 
of their source, as happens to much more resistant non-biogenic sediment 
particles.  Moreover, studies following floods show that bodies tend to 
wash toward the slackwaters marginal to the main current in a very short 
distance, so not even bloated carcasses can be carried very far down 
streams.


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Norman R. King                                       tel:  (812) 464-1794
Department of Geosciences                            fax:  (812) 464-1960
University of Southern Indiana
8600 University Blvd.
Evansville, IN 47712                      e-mail:  nking.ucs@smtp.usi.edu