| Summary: | Progress Code: completed Statement: Data quality and control were monitored by repeat measurement of the Chile sediment RR9702-42MC8 (detrital-rich) and KN7812-12BC 0-6cm SO (opal-rich) sediment standards. The samples were processed in two batches, each containing one sediment standard and one procedural blank for 22 samples. The procedural blanks were negligible (less than 1.1% of standard values). A third sample batch (n=4) was measured to analyse samples 2.9-2.91, 5.6-5.61, and 9.7-9.71; and provide duplicate analysis of sample 11.6-11.61. Purpose The sediment geochemistry can be used to reconstruct changes in environmental conditions along the East Antarctic margin of the Southern Ocean. Trace metal concentrations are reported in micrograms per gram of sediment in core C012-PC05 (64⁰ 40.517’ S, 119⁰ 18.072’ E, water depth 3104 m). Each sediment sample (100-200mg) was ground using a pestle and mortar and digested following an initial oxidation step (1:1 mixture of H2O2 and HNO3 acid) and open vessel acid on a 150 degree C hotplate using 2:5:1 mixture of concentrated distilled HCl, HNO3 and Baseline Seastar HF acid. After converting the digested sample to nitric acid, an additional oxidation step was performed with 1:1 mixture of concentrated distilled HNO3 and Baseline Seastar HClO4 acid. A 10% aliquot of the final digestion was sub-sampled for trace metal analyses. Trace metal concentrations were determined by external calibration using an ELEMENT 2 sector field ICP-MS from Thermo Fisher Scientific (Bremen, Germany) at Central Science Laboratory (University of Tasmania). The following elements were analysed in either low (LR) or medium resolution (MR): Sr88(LR), Y89(LR), Mo95(LR), Ag107(LR), Cd111(LR), Cs133(LR), Ba137(LR), Nd146(LR), Tm169(LR), Yb171(LR), Tl205(LR), Pb208(LR), Th232(LR), U238(LR), Na23(MR), Mg24(MR), Al27(MR), P31(MR), S32(MR), Ca42(MR), Sc45(MR), Ti47(MR), V51(MR), Cr52(MR), Mn55(MR), Fe56(MR), Co59(MR), Ni60(MR), Cu63(MR), Zn66(MR).
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