【摘 要】
：
The Xihuashan granitic complex is characterized by enrichment in rare-earth elements (REE). In particular, the second-stage granite (G-b) is markedly enriched i
【机 构】
：
State Key Laboratory for Mineral Deposits Research
【基金项目】
：
国家自然科学基金;教育部科学技术研究项目
论文部分内容阅读
The Xihuashan granitic complex is characterized by enrichment in rare-earth elements (REE). In particular, the second-stage granite (G-b) is markedly enriched in yttrium, and therefore contains complex associations of Y-bearing minerals. In this granite, garnet displays specific yttrium zoning with an Y-rich core and a "clean" rim. Besides minute inclusions of Y-bearing minerals, garnet involves a striking amount of Y and HREE in its central area. It is suggested that enrichment in Y in the garnet core accords with that in the melt as a result of REE magmatic fractionation. However, the "clean" rim may be the direct result of accumulation of fluid phases in the magma, which is virtually unfavorable for the entrance of REE in the garnet structure.
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