中喜马拉雅的榴辉岩近些年受到越来越多关注，与西构造结榴辉岩不同，其岩相学及峰期榴辉岩相变质时代仍存在巨大争议。本申请拟对尼泊尔东北部Arun Vally的退变榴辉岩及围岩开展系统的岩石学、地球化学及年代学研究。1）综合相平衡模拟和矿物温压计精确限定其峰期榴辉岩相及麻粒岩相叠加的温压条件。2）通过分析石榴石中的原位锆石等适合U-Pb定年的包体，以限定进变质到峰期榴辉岩相的时代；结合金红石、榍石等微区原位定年限定冷却时代。3）对榴辉岩，通过全岩主微量、同位素分析结合锆石残留岩浆核原位Hf-O同位素结果揭示其原岩类型，进而探讨其原岩性质和归属。4）通过分析退变榴辉岩中的深熔脉体，探讨大陆俯冲折返过程中的变质-深熔成因机制。综合以上研究，确立尼泊尔东北部Arun Valley退变榴辉岩及围岩的变质演化过程和形成机制。与中喜马拉雅榴辉岩带及西构造结超高压榴辉岩对比研究，探讨对喜马拉雅构造演化的约束。

The eclogite from Central Himalaya has different petrographic features and controversial peak eclogite-facies time compared with Western Himalaya Syntaxis eclogite. This project will focus on petrologic, geochemical and geochronologic study for eclogites and country gneisses from Arun Valley, Northeastern Nepal. 1) To constrain the metamorphic conditions of peak eclogite-facies and granulite-facies overprinting through combination of phase modelling and conventional geothermalbarometry. 2) To constrain the peak eclogite-facies metamorphism time using in-situ zircon inclusions U-Pb dating within garnet, and cooling history by rutile and titanite dating. 3) To reveal the protolith nature and time of eclogite by bulk-rock compositions and isotopes analysis, U-Pb, Hf-O isotopes analysis for zircon magmatic cores. 4) To constrain the correlations between granulite-facies overprinting and partial melting by petrologic and geochemical analysis the leucosome vein within retrogressed eclogite. Finally, to discuss the metamorphic evolution and genesis of Arun Vallye eclogites and country rocks. Meanwhile, together with all other eclogites from Central Himalaya and Western Himalaya Syntaxis, to discuss their geological implications for tectonic evolutions of Himalaya.