Noble gases in ultra-high-pressure eclogites and peridotites of the CCSD core

稀有气体He， Ne, Ar, Kr, Xe（共23种同位素）是幔源岩演化和历史以及流体-岩石与地壳或大气流体相互作用的重要示踪剂。各种地幔、地壳和大气成分的同位素特征，以及经常观察到的这些成分的明显元素分馏，为区分各种过程提供了巨大的灵敏度。在海洋和各次大陆背景下的海洋玄武岩玻璃和地幔捕虏体特征日益完善的背景下，本研究旨在首次获得UHP榴辉岩和橄榄岩的稀有气体同位素数据，并对中国大陆科学钻探计划（东海）核心的UHP岩石进行完整表征。同位素组成将有助于确定可能的地幔（深/浅）、地壳和大气成分。这些组分及其载体相和寄主岩的历史可以通过元素比反映的分馏过程进一步加以限制。与氧同位素和其他地球化学/岩石学参数的相关性将通过与其他小组的交叉合作来研究各自的CCSD岩心剖面。特别是，这项研究有可能深入了解地壳-地幔相互作用和收敛板块边界中的地幔行为，以及收敛板块边界内的流体作用。

The noble gases He, Ne, Ar, Kr, Xe (altogether 23 isotopes) are important tracers for the evolution and history of mantle-derived rocks, and fluid-rock interaction with crustal or atmosphere-derived fluids. Isotope signatures of various mantle, crustal and atmospheric components, and frequently observed pronounced elemental fractionation of these components offer an enormous sensitivity to distinguish a variety of processes. While oceanic basalt glasses and mantle xenoliths from both oceanic and various subcontinental settings are characterized to increasingly better degrees, this study aims to obtain the first noble gas isotope data in UHP eclogites and peridotites, and a complete characterization of UHP rocks from the core of the Chinese Continental Scientific Drilling Program (Donghai). Isotopic compositions will allow to identify possible mantle (deep/shallow), crustal and atmosphere-derived components. The history of these components and their carrier phases and host rocks can be further constrained by fractionation processes reflected in element ratios. Correlations with oxygen isotopes and other geochemical/petrographic parameters will be achieved by cross-collaboration with other groups investigating the respective CCSD core sections. In particular, this study has the potential to yield insight into crust-mantle interaction and mantle-behaviour in convergent plate-boundaries, and fluid action within convergent plate boundaries.