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

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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.