U-series ages from calcitic cold-water corals from the Amundsen Sea ...

• Main Authors: Gutjahr, Marcus, Vance, Derek, Hoffmann, Dirk L, Hillenbrand, Claus-Dieter, Foster, Gavin L, Rae, James W B, Kuhn, Gerhard
• Format: Article in Journal/Newspaper
• Language: English
• Published: PANGAEA 2013
• Subjects: Paleoenvironmental Reconstructions from Marine Sediments @ AWI AWI_Paleo; Amundsen Sea; Antarc*; Antarctic; Southern Ocean
• Online Access: https://dx.doi.org/10.1594/pangaea.839330; https://doi.pangaea.de/10.1594/PANGAEA.839330

Radiocarbon and uranium-thorium dating results are presented from a genus of calcitic Antarctic cold-water octocorals (family Coralliidae), which were collected from the Marie Byrd Seamounts in the Amundsen Sea (Pacific sector of the Southern Ocean) and which to date have not been investigated geochemically. The geochronological results are set in context with solution and laser ablation-based element/Ca ratios (Li, B, Mg, Mn, Sr, Ba, U, Th).Octocoral radiocarbon ages on living corals are in excellent agreement with modern ambient deep-water D14C, while multiple samples of individual fossil coral specimens yielded reproducible radiocarbon ages. Provided that local radiocarbon reservoir ages can be derived for a given time, fossil Amundsen Sea octocorals should be reliably dateable by means of radiocarbon.In contrast to the encouraging radiocarbon findings, the uranium-series data are more difficult to interpret. The uranium concentration of these calcitic octocorals is an order of magnitude lower than in the ... : Supplement to: Gutjahr, Marcus; Vance, Derek; Hoffmann, Dirk L; Hillenbrand, Claus-Dieter; Foster, Gavin L; Rae, James W B; Kuhn, Gerhard (2013): Structural limitations in deriving accurate U-series ages from calcitic cold-water corals contrast with robust coral radiocarbon and Mg/Ca systematics. Chemical Geology, 355, 69-87 ...