paleonet Ichnofossil question

[Penny Higgins <loligo@xxxxxxxxxxxxxxxxxxx>]

I've been asked a quick question that is outside of the realm of my 
knowledge. I hope someone here has the quick and easy answer.

This is in regards to some Cretaceous rocks in China.

"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."

Thanks for any help you may be able to provide.

~Penny

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                       Dr. Pennilyn Higgins
                        Research Associate

                             "SIREAL"
   Stable Isotope Ratios in the Environment Analytical Laboratory

         Department of Earth and Environmental Sciences
         University of Rochester
         227 Hutchison Hall
         Rochester, NY 14627

                    loligo@earth.rochester.edu

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