A ped’s story: Weathering out climatic change during the mid-Cretaceous

Abstract

The upper Ruby Ranch Member and basal Mussentuchit Member of the Cedar Mountain Formation in the vicinity of the Price River II Quarry (CEU-PR2) in the Price River area, East Central Utah, consists of fluvially derived sediments in a floodplain environment with a seasonal xeric regime. Bulk organic matter carbon isotope chemostratigraphic profiles δ 13Corg for measured sections in the CEU-PR2 area are constrained by detrital zircon ages ranging from 109 to 116 Ma (Burton et al., 2006). These δ13Corg profiles show prominent excursions and structure that have been correlated with global δ13C org chemostratigraphy of Bralower et al. (1999) and show carbon excursion events C10-C13. This correlation suggesting that the Aptian-Albian boundary is captured by the Ruby Ranch Member and makes the upper most Ruby Ranch Member and Mussentuchit Member strictly Albian in age.