Building benchmark Pliocene-Pleistocene palaeomagnetic records using sediments cored during IODP Expedition 397 (Iberian Margin Palaeoclimate)

来自伊比利亚边缘的海洋沉积物已被证明是研究地球过去气候长期（数十万年）和短期（数百年至数千年）时间尺度变化的重要档案。该档案可以与基准极地冰芯记录联系起来，并使详细的海洋，冰芯和陆地联系的研究成为可能。这个海洋沉积物参考记录可以追溯到大约140万年前。Exp. 397将在不同水深（对不同水质量敏感）的多个地点将这一参考记录扩展到大约500万年前。这组独特的沉积物档案将使我们能够回答与千年和轨道尺度气候变化、半球间相位关系以及陆地、海洋和冰芯联系有关的一系列基本问题。它们也为重建过去地球磁场方向和强度的变化提供了令人兴奋的机会。这些令人兴奋的研究机会的关键是可靠和详细的年龄模型和岩心沉积物序列的地层相关性，以便可以自信地约束事件的时间，变化率和过程的相位关系。该项目将通过生成选定岩心的高分辨率地球化学和古地磁数据（每隔1厘米）来解决这一问题。我们将：开发高分辨率的倒转/偏移、相对古强度（RPI）和古长期变化（PSV）记录，以帮助构建稳健的综合地层学和建立地磁变化动力学的基准记录；（ii）创建高分辨率环境磁记录，作为古环境/气候变化（包括千年气候变率）的敏感指标；（iii）收集x射线荧光（XRF）数据，以验证和改进洞与洞之间和点与点之间的相关性。

Marine sediments from the Iberian Margin have proven to be remarkable archives for the study of long (hundreds of thousand years) and short (hundreds to thousands of years) timescale changes in Earth's past climate. This archive can be tied to the benchmark polar ice core records and enables the study of detailed marine, ice core, and terrestrial linkages. This marine sediment reference record currently goes back about 1.4 million years. Exp. 397 will extend this reference record back to about 5 million years at multiple sites with varying water depths (sensitive to different water masses). This unique set of sediment archives will allow us to answer a list of fundamental questions related to millennial and orbital scale climate variabilities, interhemispheric phase relationships, and terrestrial, marine, and ice core linkages. They also provide exciting opportunities to reconstruct past changes in Earth's magnetic field directions and intensity. Essential to these exciting research opportunities are reliable and detailed age models and stratigraphic correlations for the cored sediment sequences, so that the timing of events, rates of change and phase relation of processes can be confidently constrained. This project will address this by generating high-resolution (every 1-cm interval) geochemical and palaeomagnetic data for selected cores. We will: develop high-resolution records of reversals/excursions, relative paleointensity (RPI), and palaeosecular variation (PSV) to help construct robust integrated stratigraphies and build benchmark records of the dynamics of geomagnetic changes; (ii) create high-resolution environmental magnetic records that are sensitive indicators of paleo-environmental/climate changes including millennial climate variability; and (iii) collect X-ray fluorescence (XRF) data to verify and improve hole-to-hole and site-to-site correlations.