Detailed REE geochemical studies of the Xingzi Group metasedimentary rocks at Lushan and rock-forming minerals such as garnet have been conducted and the results show that the REEs are partly present in the rock-formi...Detailed REE geochemical studies of the Xingzi Group metasedimentary rocks at Lushan and rock-forming minerals such as garnet have been conducted and the results show that the REEs are partly present in the rock-forming minerals and are dominantly contained in the lattice of accessory minerals. In the process of metamorphism the REEs reached partition equilibrium between garnet porphyroblast and rock and the partitioning of REEs between garnet and host rock is obviously controlled by the chemical composition of the system. The REE compositions of metamorphic veins and their minerals display remarked lanthanide tetrad effects and the element pairs Zr-Hf, U-Th and Y-Ho have also experienced remarkable fractionation with respect to the metamorphic rocks and they can be used as discriminating indicators for the occurrence of fluid processes in the process of metamorphism of the Xingzi Group.展开更多
METAMORPHIC fluids, an important type of the ore-forming fluids within the Earth’ s crust, are the necessary materials for metamorphic hydrothermal ore formation. Their direct products are varieties of synmetamorphic...METAMORPHIC fluids, an important type of the ore-forming fluids within the Earth’ s crust, are the necessary materials for metamorphic hydrothermal ore formation. Their direct products are varieties of synmetamorphic veins occurring in metamorphic rocks’. Studies on the genesis of these veins can be availablefor investigating the source material and formation processes of metamorphic hydrothermal deposit. Previous studies on metamorphic veins have focused mainly on their mineralogical, major elemental and oxygenisotopic compositions, and two different hypotheses have been advanced to account for metamorphicvein genesis. In this paper, we use rare-earth elemental method, together with field geological andpetrologic studies, to inquire into the origin of synmetamorphic veins occurring in Xingzi Group ofLushan, southeast China.展开更多
基金Project supported jointly by the Outstanding Youth Foundation (Grant No. 49625304)the Ministry of Science and Tech nology of China (Grant No. 95-Pre-39).
文摘Detailed REE geochemical studies of the Xingzi Group metasedimentary rocks at Lushan and rock-forming minerals such as garnet have been conducted and the results show that the REEs are partly present in the rock-forming minerals and are dominantly contained in the lattice of accessory minerals. In the process of metamorphism the REEs reached partition equilibrium between garnet porphyroblast and rock and the partitioning of REEs between garnet and host rock is obviously controlled by the chemical composition of the system. The REE compositions of metamorphic veins and their minerals display remarked lanthanide tetrad effects and the element pairs Zr-Hf, U-Th and Y-Ho have also experienced remarkable fractionation with respect to the metamorphic rocks and they can be used as discriminating indicators for the occurrence of fluid processes in the process of metamorphism of the Xingzi Group.
文摘METAMORPHIC fluids, an important type of the ore-forming fluids within the Earth’ s crust, are the necessary materials for metamorphic hydrothermal ore formation. Their direct products are varieties of synmetamorphic veins occurring in metamorphic rocks’. Studies on the genesis of these veins can be availablefor investigating the source material and formation processes of metamorphic hydrothermal deposit. Previous studies on metamorphic veins have focused mainly on their mineralogical, major elemental and oxygenisotopic compositions, and two different hypotheses have been advanced to account for metamorphicvein genesis. In this paper, we use rare-earth elemental method, together with field geological andpetrologic studies, to inquire into the origin of synmetamorphic veins occurring in Xingzi Group ofLushan, southeast China.
