CESEDI Collaborative Research: On the 190Pt-186Os System as a Test of Core-Mantle Interaction: Phase III

该项目的第三阶段是对早期工作的协作，多学科的延伸。PI将把同位素地球化学与实验岩石学/地球化学结合起来。目标是：1)继续精确测量各种可能来源于羽状岩的岩石的186Os/188Os，这些岩石的Pb-Os关系表明非地壳富集187Os物质的参与，并评估186Os与187Os富集之间是否存在正相关关系。2)实验研究Pt、Re和Os在越来越高的压力和温度下在液相和固相之间的分配。这项研究的目的是评估Pt， Re和Os在较大的行星体中的分配是否与在小行星核心中的分配一样。3)精确、准确地测量各种可能再循环进入地幔的地幔和地壳物质中Pt和Pt/Os的浓度。这方面研究的目的是证实或否认地壳物质再循环进入地幔对地幔-地壳混合物Pt/Os比率影响不大的初步证据。

9809569Walker Phase III of this project is a collaborative, multidisciplinary extension of earlier work. The PI's will combine isotope geochemistry with experimental petrology/geochemistry. Objectives are to: 1) Continue to precisely measure the 186Os/188Os of a variety of possibly plume-derived rocks for which Pb-Os relations suggest the involvement of non-crustal 187Os-enriched materials, and assess if there is a positive relation between 186Os and 187Os enrichment. 2) Experimentally examine the partitioning of Pt, Re and Os between liquid and solid metal phases at increasingly higher pressures and temperatures. The goal of this research is to assess whether the partitioning of Pt, Re and Os behave in larger planetary bodies as they do in asteroidal cores. 3) Precisely and accurately measure the concentrations of Pt and Pt/Os in a variety of mantle and crustal materials that may be recycled into the mantle. The goal of this aspect of the research is to confirm or deny the preliminary evidence that suggests recycling of crustal materials into the mantle little affects the Pt/Os ratio of mantle-crust mixtures.