Re: Tsagayan/Udurchukan age-Campanian?

[Tim Donovan <uwrk2@yahoo.com>]

--- David Marjanovic <david.marjanovic@gmx.at> wrote:

> >  I've repeatedly argued against the putative late
> > Maastrichtian age of the Tsagayan or Udurchukan
> > formation. Logically, a unit with abundant
> lambeosaurs
> > of Campanian aspect should be older.
> 
> "Logically" and "judging from the Hell Creek Fm" is
> not the same. How do you 
> know they are "of Campanian aspect" when you only
> know that lambeosaurs of 
> that "aspect" are restricted to the Campanian _in
> North America_?


   The Nemegt is certainly similar to the Hell Creek
in yielding very few lambeosaurs, and there is no
evidence for any lambeosaur other than
Hypacrosaurus(may=Barsboldia, see THE DINOSAURIA)in
either. Lambeosaurs seem more abundant in the
apparently Djadokhtan beds at Laiyang. The
parasaurolophine Tsintaosaurus suggests the unit is
coeval with Jiayin.


> 
> > Yesterday, while
> > going over recent JVP issues, I noted information
> > which suggests the Tsagayan actually IS of
> Campanian
> > age.
> >
> > [...]
> 
> This is a lot more convincing. 

  Then don't worry about the above. :)
> 
> 



        
                
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