Exploring the potential of a new North American Plio-Pleistocene paleoclimate record from the yet unopened drill core from paleo-Lake Idaho

这里提出了一个跨学科的项目，以探索一个新的，最近钻探的，但尚未打开的高质量湖泊沉积物岩心的古气候潜力，该岩心来自北美中纬度的一个关键位置。来自科隆大学、海德堡大学和<s:1>宾根大学的三个研究小组与美国明尼苏达大学LacCore设施合作，提出了对美国西部一个已灭绝的大裂谷古爱达荷湖的上新世-更新世记录进行多代理评估的建议。由ICDP项目热点恢复，这个湖钻岩心成为钻取蛇河平原火山序列的“红利”。在贝加尔湖和Elgygytgyn湖钻探项目之后，古爱达荷湖沉积物序列实际上是icdp资助的第三个湖泊钻探岩心记录，它在一个序列中恢复了上新世温暖时期、上新世-更新世过渡时期和约2.7 Ma的北半球冰川开始时期。这是北美大陆首次出现这种记录。建议3个课题组协同开展(1)钻孔、描述和测井，重建上新世—更新世古爱达荷湖的沉积史；(2)结合磁地层测量、玄武岩绝对定年、tephra定年和轨道校正技术，建立了恢复层序的年龄模型；(3)结合元素和稳定同位素地球化学、大块沉积物组成、粒度和花粉分析，建立最有前景的古气候指标；(4)开展基于花粉的古气候重建；(5)验证了一系列关于上新世中晚期气候遥相关、经向大气热湿输送以及大尺度大气环流变化在约2.7 Ma北半球冰川启动中的潜在作用的假设。

An interdisciplinary project is proposed here to explore the paleoclimate potential of a new, recently drilled, but not yet opened high-quality lake sediment core from a key location in mid-latitude North America. Interlinked studies of three groups from the Universities of Cologne, Heidelberg and Tübingen in collaboration with the LacCore facility of the University of Minnesota (USA) are proposed to conduct a multi-proxy evaluation of the Plio-Pleistocene record of an extinct large rift paleo-Lake Idaho, Western USA. Recovered by the ICDP Project HOTSPOT, this lake drill core became a 'bonus' of drilling for under- and overlying volcanic sequences of the Snake River Plain. After the Lake Baikal and Lake Elgygytgyn Drilling Projects, the paleo-Lake Idaho sediment sequence is in fact the third ICDP-funded lake drill core record to have recovered the warm Pliocene period, the Plio-Pleistocene transition and the initiation of the Northern Hemisphere glaciations at ca. 2.7 Ma, all in one sequence. It is the first record of this kind in continental North America. Coordinated effort of three research groups is proposed to (1) conduct core opening, description and logging and reconstruct the depositional history of the Plio-Pleistocene paleo-Lake Idaho; (2) construct the age model for the recovered sequence using a combination of magnetostratigraphic measurements, absolute dating on basalts and tephra and orbital tuning techniques; (3) establish the most promising paleoclimate proxies from the combination of elemental and stable isotope geochemistry, bulk sediment composition, grain size and pollen analyses; (4) develop pollen-based paleoclimate reconstructions; and (5) test series of hypotheses on climate teleconnections, meridional atmospheric transport of heat and moisture during the mid-late Pliocene, and the potential role of large-scale atmospheric circulation changes in initiating Northern Hemisphere glaciations at ca. 2.7 Ma.