Scanning XRF and environmental magnetic data across the Miocene-Pliocene boundary from ODP Site 967 (Eastern Mediterranean)

The Mediterranean was partially desiccated as the Atlantic-Gibraltar gateway was closed ~6 million years (Ma) ago. The gateway collapsed at ~5.33 Ma (Miocene-Pliocene boundary), resulting in a catastrophic flood which refilled the basin within 2 years. Here we use scanning x-Ray fluorescence (XRF) and anhysteretic remanent magnetization (ARM) data from ODP Site 967 (eastern Mediterranean) to analyze the nature of sediment deposition across the flooding event (5.35-5.12 Ma). Scanning XRF was measured with a 3rd generation Avaatech XRF core scanner. Element 'counts' for the entire interval were converted into element concentrations by multivariate log-ratio calibration, using new wavelength dispersive (WD)-XRF reference element concentrations. XRF data (Ba/Ti filter) was used to generate the chronology, by tuning Ba/Ti peaks to insolation maxima (precession minima). ODP967 U-channel samples were sliced at 1-cm intervals into discrete non-magnetic 2×2×2 cm plastic cubes and measured for ARM on a 2-G Enterprises cryogenic magnetometer.