Re: Tuba City, AZ tracks

["Rob Gay" <rob_redwing@hotmail.com>]

>   I just came back from a trip through Arizona, and had stopped by and 
> checked out the dino tracks outside of Tuba City.  Has anyone else been 
> there? I am curious about what age those tracks have been guessed to be.<
Indeed I have been there. Here's my two bits. These tracks are in the 
uppermost Moenave formation, practically on the contact between the Moenave 
and the Kayenta. The current thinking is that the Wingate, the Moenave, the 
Kayenta and the Navajo are all early Jurassic. However, there has been some 
talk about the J-0 unconformity actually being traced to above the Kayenta, 
which would put the Moenave, Wingate and Kayenta into the latest Triassic. 
There has also been some work done suggesting that the Chinle is lower in 
the Triassic than perviously though, which would support a lower position 
for the Moenave/Wingate/Kayenta series. Also, there are still mammal-like 
reptiles (I know this isn't the cladistically prefered term, but I'll use it 
here anyways) found in the Kayenta formation (e.g. _Kayentatherium_), which 
would either help support a lower position, or be an odd left-over from the 
earlier period.
So, to make a long story short...they're probably Jurassic, but there seems 
to be more evidence appearing supporting a lower position.

> Thanks if anyone can help!<
Hope this wasn't too confusing, and it helped!
Peace,
Rob

Student of Geology
Northern Arizona University
P.O. Box 20840
Flagstaff, Az. 86011
AIM: TarryAGoat
"A _Coelophysis_ with feathers?"

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