【摘要】 本文系统地总结了近年来有关新疆西南天山超高压变质带在野外地质产状、岩石学、矿物学、地球化学和年代学等方面研究取得的进展。根据野外地质产状特征,西南天山出露的榴辉岩可以分为三类:即在蓝片岩中呈透镜体的块状榴辉岩、保存有玄武岩岩枕的枕状榴辉岩和夹杂在大理岩中的条带状榴辉岩。详细的岩石学研究表明它们都经历过超高压变质作用,其变质作用演化经历了3个阶段:峰期榴辉岩阶段（560～600℃,4.95～5.07GPa）、主期榴辉岩阶段（598～496℃,25.72～26.66±1kbar）和退变绿帘石蓝片岩相阶段。地球化学研究显示其原岩相当于源于富集地幔的(ε_Nd-1.4～-0.4)具有 OIB 特点的变碱性玄武岩、源于亏损地幔的(ε_Nd=+6.7～+7.4)具有 NMORB 特点的洋中脊玄武岩和源于较富集地幔的(ε_Nd=-2.5～+3.2)具有 EMORB 特点的洋中脊玄武岩,它们形成于海山环境下的洋壳。榴辉岩中锆石 SHRIMP定年结果表明榴辉岩的原岩形成于石炭纪（>310Ma）之前,洋壳开始俯冲发生在二叠纪末（280～290Ma）,高压一超高压变质发生在三叠纪（220～230Ma）。结合在其北侧低压麻粒岩带的发现,提出了新疆西南天山超高压变质带双变质带构造演化模式。更多还原

【Abstract】 The recent study in geological occurrence,petrology,geochemistry and geochronology of the UHP metamorphic belt in Southwestern Tianshan has been summarized in this paper.According to their geological occurrences,the eclogites in Southwestern Tianshan can be grouped into three types,i.e.,the lenticular body around by blueschist,pillow structure eclogite and banded eclogite within marble.The petrological study shows that all these three kinds’ eclogites have undergone ultrahigh pressure metamorphism. Their UHP metamorphic evolution can be divided into three stages:peak UHP eclogite stage with PT conditions of 560～600℃ and 4.95～5.07 GPa,main eclogite stage with PT conditions of 598～496℃ and 25.72～26.66±1kbar and retrograde stage of epidote blueschist faces.The geochemical study suggests that the protoliths of Southwestern Tianshan cclogites should be the affinity of OIB originated from the enriched mantle with ε_Nd=-1.4～-0.4,NMORB from depleted mantle with ε_Nd=+6.7～+7.4 and EMORB from the enriched mantle with ε_Nd=-2.5～+3.2.The above three protoliths of eelogites may be formed in sea mountain environment.The SHRIMP dating of zircon from eclogites shows that the protoliths of eelogite were formed before Carboniferous （>310 Ma）,the oceanic subduetion Tarim plate northward beneath Yili-central Tianshan Craton began in the end of Permian （280～290 Ma） and the HP-UHP metamorphism happened in Triassic （220～230 Ma）.Combined with the discovery of the low pressure granulites in the north side of the UHP belt,the tectonic model based on the paired metamorphic belt in Southwestern Tianshan has been proposed in this paper.更多还原