Re: paleonet Ichnofossil question

[bivalve@xxxxxxxxxxxxxxxxxxxxxxxxxx]

>"Have you ever noticed bioturbation in the Cretaceous
>strata (or other strata)?
>
>While mapping, i have noticed some heavily bioturbated
>strata and  j-shaped burrows.  My knowledge of trace
>fossils is lacking, but what  i remember is that these are
>usually marine.  i ask because the  strata i find this in
>looks neogene, but i want to call it Cretaceous  b/c of the
>fossils."

Bioturbation is quite common in Cretaceous and Neogene
strata, as well as most other Phanerozoic intervals.  It
tends to be heavier in marine than non-marine settings, but
is present in both.  Some burrow types are more common in or
confined to a particualr time interval, but many are found
in many ages.  

Dr. David Campbell
425 Scientific Collections
Box 870345, University of Alabama
Tuscaloosa AL 35487-0345
"James gave the huffle of a snail in danger/ But no one
heard him at all."-A. A. Milne