Trace element and boron isotopic composition of Drake Passage deep-sea corals ...

• Main Authors: Stewart, Joseph, Rae, James, Spooner, Peter, Robinson, Laura, Littley, Eloise, Cole, Cathy
• Format: Dataset
• Language: English
• Published: UK Polar Data Centre, Natural Environment Research Council, UK Research & Innovation 2020
• Subjects: "EARTH SCIENCE","OCEANS","OCEAN CHEMISTRY","TRACE ELEMENTS"; "EARTH SCIENCE","PALEOCLIMATE","OCEAN/LAKE RECORDS","CORAL DEPOSITS"; "EARTH SCIENCE","PALEOCLIMATE","OCEAN/LAKE RECORDS","ISOTOPES"; "EARTH SCIENCE","OCEANS","OCEAN CIRCULATION"; Drake Passage; Southern Ocean; boron isotopes; deep-sea coral; trace element
• Online Access: https://dx.doi.org/10.5285/ee141bb8-ecc2-4305-9978-05fe9521f10a; https://data.bas.ac.uk/full-record.php?id=GB/NERC/BAS/PDC/01214

Changes of circulation pattern in the Southern Ocean have been invoked to explain a significant portion of the increase in the atmospheric carbon dioxide during the last deglaciation. However, the accurate timing and thus underlying mechanisms of these changes are still controversial, requiring knowledge of different water masses movements with absolute age constraints. Aragonitic scleractinian deep-sea corals, recovered from a broad range of depths in the Drake Passage, provide a unique opportunity to investigate Southern Ocean ventilation with precise U-Th age control. This data submission includes trace element and delta11B for Drake Passage corals. Funding was provided by the NERC standard grant NE/N003861/1. ... : Whole septa and attached theca were taken from cup corals samples using a rotary cutting tool. This tool was further used to remove surficial oxide coatings and any chalky white altered carbonate. Microstructures within cold-water corals are known to exhibit highly contrasting delta11B, therefore where sufficient sample material allowed, multiple sub-samples (typically duplicates) were measured to assess microstructural bias. Coral fragments were finely crushed using a pestle and mortar before a 2 to 4 mg aliquot of the homogenous powder was taken. A warm 1% H2O2 (buffered in NH4OH) oxidative clean and weak acid polish (0.0005 M HNO3) was performed on powders. Samples were then dissolved in distilled 0.5 M HNO3. All analyses were carried out at the Univ. of Bristol and Univ. of St Andrews. An aliquot of the dissolved sample was analyzed by ICP-MS using well-characterised, matrix-matched, synthetic standard solutions to yield trace metal ratios to calcium. Repeat analysis of NIST RM 8301c (n=35) yielded ...