Although the presence of a greenhouse climate is well established for the Cretaceous, documenting the details of the timing and magnitude of climate and oceanographic change is challenging due to the combination of local, regional, and global influences that shape the geologic record. This report by Joo and Sageman documents new δ13C data from three cores from the Late Cretaceous of the central Western Interior Basin to construct a composite δ13C reference curve that spans middle Cenomanian to early Campanian time, and which is linked to new radioisotopic and astrochronologic data. The new δ13C framework allows revised and improved age control to time equivalent sections with δ13C records, but which may lack in situ biostratigraphy and geochronology. Collectively, these data should provide insights to regional and global changes in carbon cycling and sea-level change, and deposition of organic-rich sediment.
Interior Basin. U.S.A. by Young Ji Joo and Bradley B. Sageman