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RE: mammals over dinosaurs in continuous sequence



Okay, if we're going with areas where the boundary is indistinct,
then Big Bend National Park, specifically the Tornillo Flats area
is also a candidate.

Jim Yahr
Assistant Scientist
Carlsbad Environmental Monitoring & Research Center
New Mexico State University
1400 University Dr.
Carlsbad, NM  88220
Phone:  505/234-5524
Fax: 505/887-3051


On Wednesday, April 14, 1999 6:29 PM, Jerry D. Harris 
[SMTP:102354.2222@compuserve.com] wrote:
> Message text written by INTERNET:Dinogeorge@aol.com
> >All these responses are very interesting, but the question being addressed
> is
> where in the world is there a K-T boundary sequence with dinosaur fossils
> below the boundary and no dinosaur fossils, only mammals, above it.<
>
> There's a site just west of Denver (in Golden, actually) called South Table
> Mesa which is approximately 2/3 Late Cretaceous Denver Formation and 1/3
> (at the top) Early Paleocene Denver Formation.  Both sections have produced
> fossils, dinosaurs below (the type of _Ornithomimus velox_ was found in the
> same formation very nearby; I'm not sure about mammals in the Cretaceous
> part), and a nice partial skull of _Baioconodon denverensis_ as well as
> plant fossils above.  Oddly, last I heard, no one had found iridium on the
> mesa, and the precise location (stratigraphically speaking) of the boundary
> is unknown.  However, the presence throughout the formation of dated
> volcanic ashes demonstrates that the boundary is in there, somewhere...
> Anyone who's been to Dinosaur Ridge and seen the footprints in the Dakota
> there have inevitably looked north and seen the mesa.
>
>                 _,_
>            ____/_\,)                    ..  _  
> --____-===(  _\/                         \\/ \-----_---__
>            /\  '                        ^__/>/\____\--------
> __________/__\_ ____________________________.//__.//_________
>
>                      Jerry D. Harris
>                  Fossil Preparation Lab
>           New Mexico Museum of Natural History
>                    1801 Mountain Rd NW
>                Albuquerque  NM  87104-1375
>                  Phone:  (505) 899-2809
>                   Fax: ; (505) 841-2866
>                102354.2222@compuserve.com