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


At 03:47 PM 10/18/97 -0400, Scott McCray wrote:
>  Never the less, if
>_Triceratops_ is being found inland at all, then it is reasonable to
>assume that at least some lived inland.  I cannot think of a 
>mechanism that would have moved material from the shores 
>significantly inland.

Quite true.

Unfortunately I do not have precise provenance of all specimens available
to be sure one way or the other.  I do not *know* of any truly inland
specimens of _Triceratops_, but that is not conclusive, given my limited

>       I think you may be right about some of the specimens being found
>in overbank deposits.  What I'm confused about is why these deposits
>indicate a proximal source.  I see little reason why a river in flood
>cannot carry material out of an uplands environment down system, and 
>then deposit it in an overbank deposit (particularly if the material
> happens to be a carcass  or part of one).

As a general rule, long distance transport of large objects, like
_Triceratops_ carcasses is limited to relative fast moving water.  The slow
moving water that produces overbank fines cannot really easily move heavy
material.  After all, that is why it is depositing *fine* grained material.

Admittedly a carcass at the bloat stage can float quite far, even in
relatively quiet water, but that is a very rare sort of event, and the such
floating carcasses rarely get deposited on floodplains.  They more often
get caught in a snag or sandbar on the river, or get shoaled at the river
mouth, or decay to pieces out at sea. Ankylosaurs seem to have been
particularly prone to this, considering how many of them have been found in
marine deposits.

At least his is my basic understanding of the relevant taphonomy.
[I am finding it hard to find good advance texts on taphonomy to get a good
understanding of all aspects of that science - sigh].

May the peace of God be with you.         sarima@ix.netcom.com