ORGANIC CARBON-ISOTOPE CHEMOSTRATIGRAPHY OF THE LOWER CRETACEOUS CEDAR MOUNTAIN FORMATION, UTAH

Paleosols and lacustrine sediments of the Yellow Cat Member (YCM), Cedar Mountain Formation, East-Central Utah were collected and analyzed for bulk organic carbon isotopes (δ¹³C_org). The results were used to construct a C-isotope curve that can then be correlated with global C-isotope records of similar age. The YCM is thought to span the Barremian to Albian based on dinosaur faunal assemblages. Correlation with distinct isotope excursions such as those associated with the Selli Event or OAE 1a would allow insight into the behavior of the terrestrial climate in response to oceanic anoxia events and C-cycle perturbations during Aptian-Albian time. Preliminary data ranges between a minimum of -26.12‰ and a maximum of -22.72‰ with an average of -24.00‰ (VPDB) and shows a distinctive -3‰ isotope excursion at the base of the studied section. The preliminary data appears to correlate with the upper Barremian C-isotope curves but additional data needs to be collected prior to definitive correlation.