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详细的岩石学研究表明,大别-苏鲁造山带橄榄岩和辉石岩记录了俯冲带之上地幔楔的交代和变质信息.在苏鲁芝麻坊石榴二辉橄榄岩中识别了七期变质矿物组合,反映了大陆俯冲-碰撞-折返过程中多期的变质和交代作用.大别毛屋石榴斜方辉石岩同样保存了大量的交代结构,高Ni和富集轻稀土(LREE)的斜方辉石核部包裹了早期原岩橄榄石,表明它是俯冲地壳熔/流体与原岩橄榄石在超高压条件下反应的产物.毛屋石榴斜方辉石岩记录了六期变质作用,对应了岩石从浅部地幔楔沿俯冲隧道进入深部地幔楔,最后随陆壳岩石折返回浅部地壳的全部过程.其中石榴石变斑晶核部包裹了大量的以含水矿物为主的角闪岩相多相包裹体,具有高XMg和Ni含量,并富集大离子亲石元素(LILE)和LREE,表明它们是早期岩石在浅部地幔楔与地壳流体交代的产物.角闪岩进入深部地幔楔经历高压和超高压变质,早期含水矿物完全脱水分解,形成超高压石榴斜方辉石岩,释放LILE和LREE富集的流体进入上覆高温地幔楔,从而导致高温地幔楔发生部分熔融并产生岛弧岩浆.
Detailed petrological studies indicate that the Dabie-Sulu orogenic belts and pyroxenites record metasomatism and metamorphic information of mantle wedges above the subduction zone, and the Seventh Metamorphosis Mineral assemblages, which reflect the multi-stage metamorphism and metasomatism during the subduction-collision-reentry process in China.A large amount of metasomatic structures are also preserved in the pomegranate rhombic pyroxenes from the Dabie Mao House, with high Ni and LREE enrichment The orthopyroxene nucleus encased the early Proterozoic olivine, indicating that it was the product of reaction between subducted crustal melt / fluid and protolith olivine under ultra-high pressure. , Corresponding to the rock from the shallow mantle wedge along the subducting tunnel into the deep mantle wedge, and finally with the continental crust rock fold back to the shallow crust of the whole process .Porphyrin nuclei wrapped a large number of water-based minerals in the corner The amphibolite facies polyphase inclusions, which have high XMg and Ni contents, are enriched in LILE and LREE, indicating that they were the products of metasomatism of early mantle wedge and shallow crustal fluids. Deep mantle wedge experiences high pressure and ultra Modification pressure, aqueous mineral early decomposed completely dehydrated, orthorhombic form EHV garnet pyroxenite, releasing the fluid into the LILE and LREE enriched mantle wedge overlying high temperature, leading to high temperature and melted mantle wedge generating portion generates arc magmas.