Plio-Pleistocene coupled benthic stable isotope and Mg/Ca measurements from Site 1209 in the Northwest Pacific

Stable isotopes were measured on benthic foraminifera species Cibicidoides wuellerstorfi from ODP Site 1209 on the Shatsky Rise in the Northwest Pacific Ocean. Approximately 5 – 7 specimens were analysed at c. 4cm resolution along the core from 33 m - 58 m depth along the core for both oxygen and carbon isotopes using a VG ISOGAS SIRE dual inlet isotope ratio mass spectrometer at the Godwin Laboratory for Palaeoclimate Research at the University of Cambridge. For the section between 34 - 43 m depth along the core, Mg/Ca ratios were measured on the benthic foraminifera species Uvigerina peregrina. The samples underwent a modified reductive and oxidative cleaning process described in Boyle and Kegwin, 1982 and Barker et al., 2003 respectively, and were then analysed for trace metals by ICP-MS on a Thermo-Scientific Element 2 at the University of Southampton. The coupled stable isotopes and Mg/Ca measurements were converted to bottom-water temperature and seawater d18O values using the PSU Solver model of Thirumalai et al., 2017. Samples were put on an age model using a bayesian tie-point algorithm which matched oxygen isotope values to that of the ProbStack record of Ann et al., 2017.