Authigenic neodymium isotope and radiocarbon data from the Blake Bahama Outer Ridge (KNR140 JPC12 and ODP Sites 1059-1062) ...

• Main Author: Pöppelmeier, Frerk
• Format: Article in Journal/Newspaper
• Language: English
• Published: PANGAEA 2019
• Subjects: Blake Ridge; Leg 172; Nd isotopes; radiocarbon; Finn; North Atlantic Deep Water; North Atlantic; Northwest Atlantic
• Online Access: https://dx.doi.org/10.1594/pangaea.905470; https://doi.pangaea.de/10.1594/PANGAEA.905470

Neodymium (Nd) isotopes extracted from authigenic sediment phases are increasingly used as a proxy for past variations in water mass provenance. To better constrain the controls of water mass provenance and non-conservative effects on the archived Nd isotope signal, we present a new depth transect of Nd isotope reconstructions from the Blake Bahama Outer Ridge along the North American continental margin covering the past 30 ka. We investigated five sediment cores that lie directly within the main flow path of the Deep Western Boundary Current, a major advection route of North Atlantic Deep Water. We found offsets between core tops and seawater Nd isotopic compositions that are observed elsewhere in the Northwest Atlantic. A possible explanation for this is the earlier suggested redistribution of sediment by nepheloid layers at intermediate as well as abyssal depths, transporting material downslope and along the continental margin. These processes potentially contributed to Nd isotope excursions recorded in ... : Supplement to: Pöppelmeier, Frerk; Blaser, Patrick; Gutjahr, Marcus; Süfke, Finn; Thornalley, David J R; Grützner, Jens; Jakob, Kim A; Link, Jasmin M; Szidat, Sönke; Lippold, Jörg (2019): Influence of ocean circulation and benthic exchange on deep Northwest Atlantic Nd isotope records during the past 30,000 years. Geochemistry, Geophysics, Geosystems ...