Major, trace element and Pb isotope data of basalts from the flanks of the Reykjanes Ridge, IODP Expedition 395C

Major, trace element and Pb isotope data are reported here for basalts recovered by drilling at the flanks of the Reykjanes Ridge, south of Iceland, during IODP Expedition 395C (2020-2022). The drilling targeted V-shaped ridges and V-shaped troughs forming the flanks of the Reykjanes Ridge. There were 4 sites drilled and sampled, and these include holes: U1554 (4F) - located on V-shaped trough 2B, holes U1555 (5I + 5G) - located on V-shaped trough 1, U1562 (2B), located on V-shaped ridge 3, and U1563 (3B) - located on V-shaped ridge 2A. Samples are predominately volcanic glasses and were recovered from cores drilled from up to 150m below the sediment-basement interface where they penetrated a series of pillow and sheet flow lavas. The sample name corresponds to the site, hole, core section and depth interval (see IODP Exp 395 site reports for details). Fresh volcanic glass was separated, cleaned in deionised water, picked under a binocular microscope to remove and altered material, cleaned again and then dissolved in HF and HCl prior to analyses. Major and trace elements abundances were analysed on an ICP-MS with a selection of geological reference materials (GRMs) used as standards. Pb isotopes ratios (206/204, 207/204 and 208/204) were measured on a neptune multicollector ICP-MS following using a double spike technique applied to the sample solutions. Reported here are the measured values of the GRMs and their uncertainties. The aim of this study was to test the hypothesis that the V-shaped ridges are the result of temperature and compositional pulses in a mantle plume, that is postulated to rise beneath Iceland and spread outward where it intersects the mid-ocean ridge to the south, and the effects of those pulses on climate over the last ~20Ma.