Age model and Nd isotope ratios of DSDO Hole 43-386 and ODP Hole 210-1276A ...

• Main Authors: Robinson, Stuart A, Vance, Derek
• Format: Article in Journal/Newspaper
• Language: English
• Published: PANGAEA 2012
• Subjects: Drilling/drill rig; Leg210; Joides Resolution; Ocean Drilling Program ODP; Vance; North Atlantic
• Online Access: https://dx.doi.org/10.1594/pangaea.817120; https://doi.pangaea.de/10.1594/PANGAEA.817120

Modern thermohaline circulation plays a role in latitudinal heat transport and in deep-ocean ventilation, yet ocean circulation may have functioned differently during past periods of extreme warmth, such as the Cretaceous. The Late Cretaceous (100-65 Ma) was an important period in the evolution of the North Atlantic Ocean, characterized by opening ocean gateways, long-term climatic cooling and the cessation of intermittent periods of anoxia (oceanic anoxic events, OAEs). However, how these phenomena relate to deep-water circulation is unclear. We use a proxy for deep-water mass composition (neodymium isotopes; e-Nd) to show that, at North Atlantic ODP Site 1276, deep waters shifted in the early Campanian (~78-83 Ma) from e-Nd values of ~-7 to values of ~-9, consistent with a change in the style of deep-ocean circulation but >10 Myr after a change in bottom water oxygenation conditions. A similar, but more poorly dated, trend exists in e-Nd data from DSDP Site 386. The Campanian e-Nd transition observed in ... : Supplement to: Robinson, Stuart A; Vance, Derek (2012): Widespread and synchronous change in deep-ocean circulation in the North and South Atlantic during the Late Cretaceous. Paleoceanography, 27(1), PA1102 ...