摘要
俯冲带控制着地球内部和表层的物质与能量交换。硼(B)是一个质量轻的流体活动性元素。B及其同位素体系是理解俯冲-碰撞带流/熔体活动和物质循环的重要工具。本文综述了俯冲板块中各储库的硼含量和同位素组成以及主导硼分配的关键矿物。介绍了目前对大洋俯冲带弧前、弧下和弧后深度下硼循环的主要认识;简要介绍了刚起步的大陆俯冲-碰撞带硼循环研究。阐述了含电气石(超)高压变质岩在俯冲带硼迁移研究中的重要性。指出今后需深化含水矿物在不同地温梯度下脱水/熔融过程中硼同位素分馏研究,加强流/熔体包裹体硼同位素分析技术及应用研究。由于B及同位素可有效区分大洋地壳和大陆地壳物质,未来将在造山带演化和地球深部物质循环研究中扮演更重要的角色。
Subduction zones regulate the exchange of material and energy between the interior and surface system of the Earth.Boron(B)is a light and fluid-mobile element.B and its isotopes are important tools to understand the fluid/melt activity and material cycling in subduction-collision zones.In this study,I have summarized the B concentrations and isotopic compositions of various geological reservoirs in subducted slabs,introduced present main understandings on the B cycling at fore-arc,sub-arc,and beyond-arc depths in the oceanic subduction zone and briefly introduced the nascent research field on the B cycling in continental subduction-collision zones,and also have elucidated the importance of tourmaline-bearing(ultra)high-pressure metamorphic rocks for understanding the B transfer in the subduction zone.It is expected that the research on fractionation behavior of B isotopes in processes of the metamorphic dehydration or partial melting of hydrous minerals at different geothermal gradients should be deeply undertaken and develop the analytical techniques on B isotopes of fluid/melt inclusions.Because B and its isotopes can be used to effectively distinguish the oceanic and continental crust materials,they are expected to play a more significant role for investigating the evolution of orogenic belt and material cycling in the interior of the Earth in the future.
作者
郭顺
GUO Shun(State Key Laboratory of Lithospheric Evolution,Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing 100029,China;Innovation Academy for Earth Science,Chinese Academy of Sciences,Beijing 100029,China)
出处
《矿物岩石地球化学通报》
CAS
CSCD
北大核心
2021年第5期1049-1060,I0002,共13页
Bulletin of Mineralogy, Petrology and Geochemistry
基金
国家自然科学基金项目(41922013,41672059)
中国科学院青年创新促进会项目(2017090)。
关键词
硼
俯冲带
同位素分馏
物质循环
流体
boron
subduction zone
isotope fractionation
material cycling
fluid
