广东白云山混合岩熔体/流体包裹体研究及其对华南早古生代深熔作用的约束

华南早古生代造山运动伴随强烈的地壳深熔作用，形成大量深熔花岗质岩石和混合岩，其深熔机制和熔体演化的确切过程尚不清楚。原生熔体和流体包裹体作为深熔作用的直接记录，有望解决上述问题。广东白云山片麻岩-混合岩-花岗岩组合是研究华南早古生代地壳深熔作用的理想对象，前期研究表明混合岩中发育原生熔体和流体包裹体。申请者在已有工作基础上，拟开展细致野外和镜下工作，查明混合岩中熔体和流体包裹体类型、分布和组合特征，进而对单个包裹体进行显微测温和成分分析，获取熔体形成与演化过程中的P（压力）、T（温度）、X（成分）量化参数；结合片麻岩、混合岩和花岗岩的年代学和原位微区元素-同位素地球化学研究，深入剖析三者的成因联系，精细重建熔体形成与演化过程中的物理化学条件和熔体成分。预期成果可为华南早古生代深熔机制及熔体演化过程提供直接约束，为探索大陆地壳深熔作用和地壳演化提供新的思路。

The Early Paleozoic orogeny was accompanied by intense crustal anatexis with numerous anatectic granitoids and migmatites occurred, and the mechanism and detailed melt evolution process of anatexis remained unknown. The primary melt/fluid inclusions, which can be the direct records of anatexis, have the potential to resolve the abovementioned problems. The gneiss-migmatite-granite suite in the Baiyunshan area (Guangdong) is an ideal object to research the Early Paleozoic crustal anatexis in South China. Previous studies suggested that a large number of primary melt/fluid inclusions are well-preserved in the migmatite. Based on the preliminary works, detailed field work and micromorphology observations will be carried out to investigate the characteristics of inclusion types, distribution and assemblages. Melt/fluid inclusion microthermometry and composition analyses are used to obtain quantitative results of the P (pressure)-T (temperature)-X (composition) for the melt during formation and evolution processes. Combined with geochronological and in-situ elemental-isotopic study of the gneiss, migmatite and granite, we deeply dissect the genetic links between them, and finely reconstruct the physicochemical conditions and melt compositions during melt evolution. The expected results can provide direct constraints on the Early Paleozoic crustal anatexis mechanism and melt evolution process in South China, which also will provide new thoughts to probe the crustal anatexis and crustal evolution.