大洋岩石圈与地幔动力学超净实验室激光原位微区分析系列科研成果
激光原位微区分析不同于全岩分析,可以获取激光斑束几十微米直径范围内地质样品的地球化学成分,因此是解析固体地球科学问题的重要手段。近日来,基于中科院海洋所大洋岩石圈与地幔动力学超净实验室所建立的成熟的激光原位微区分析方法,地质室肖媛媛课题组在国际高质量SCI期刊《Journal of Petrology》、《Journal of Geophysical Research: Solid Earth》等发表了一系列重要成果。
最初认为埃达克质岩浆源于俯冲年轻洋壳部分熔融,然而对其成因仍存在较大争议。肖媛媛等人通过建立大洋岩石圈与地幔动力学超净实验室激光原位微区分析方法,系统研究了北祁连造山带两个岩体花岗岩类和铁镁质暗色包体(MME)中各组成矿物成分,揭示了同碰撞花岗岩类及MME中各微量元素的主要赋存矿物如榍石等和主要造岩矿物均具有很强的元素赋存能力,从矿物学的角度验证了MME与花岗岩类都源于俯冲洋壳的部分熔融,验证了“大陆碰撞带为陆壳增长主要场所”这一假说。通过对比两个岩体的矿物成分,首次揭示了埃达克质岩类高Sr/Y、La/Yb比值的特征是由母岩浆成分与母岩浆成分所影响的榍石等矿物结晶分异所造成,而决定二者的最终原因是俯冲洋壳成分的不均一性。相关成果发表在岩石学最好的刊物《Journal of Petrology》。激光剥蚀矿物和激光聚焦示意图
1. Xiao, Y.Y., Chen, S., Niu, Y.L., Wang, X.H., Xue, Q.Q., Wang, G.D., Gao, Y.J., Gong, H.M., Kong, J.J., Shao, F.L., Sun, P., Duan, M., Hong, D., Wang, D., 2020. Mineral compositions of syn-collisional granitoids and their implications for the formation of juvenile continental crust and adakitic magmatism. Journal of Petrology 61.
2. Sun, P., Niu, Y.L., Guo, P.Y., Duan, M., Wang, X.H., Gong, H.M., Xiao, Y.Y., 2020. The lithospheric thickness control on the compositional variation of continental intraplate basalts: A demonstration using the Cenozoic basalts and clinopyroxene megacrysts from eastern China. Journal of Geophysical Research 125.
原文链接:https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2019JB019315
相关论文列表:
1. Chen, Y.H., Niu, Y.L., Shen, F.Y., Gao, Y.J., Wang, X.H., 2020. New U-Pb zircon age and petrogenesis of the plagiogranite, Troodos ophiolite, Cyprus. Lithos 362/363, 10547.
2. Xue, Q.Q., Niu, Y.L., Chen, S., Sun, P., Duan, M., Gao, Y.J., Hong, D., Xiao, Y.Y., Wang, X.H., Guo, P.Y., 2020. Tectonic significance of Cretaceous granitoids along the southeast coast of continental China. Geological Journal 55, 173-196.
3. Chen, Y.H., Niu, Y.L., Wang, X.H., Gong, H.M., Guo, P.Y., Gao, Y.J., Shen, F.Y., 2019. Petrogenesis of ODP Hole 735B (Leg 176) oceanic plagiogranite: Partial melting of gabbros or advanced extent of fractional crystallization? Geochemistry, Geophysics, Geosystems 20, 2717-2732.
4. Kong, J.J., Niu, Y.L., Sun, P., Xiao, Y.Y., Guo, P.Y., Hong, D., Zhang, Y., Shao, F.L., Wang, X.H., Duan, M., 2019. The origin and geodynamic significance of the Mesozoic dykes in eastern continental China. Lithos 332/333, 328-339.
5. Gao, Y.J.., Niu, Y.L., Duan, M., Xue, Q.Q., Sun, Pu, Chen, S., Xiao, Y.Y., Guo, P.Y., Wang, X.H., Chen, Y.H., 2019. The petrogenesis and tectonic significance of the early Cretaceous intraplate granites in eastern China: The Laoshan granite as an example. Lithos 328/329, 200-211.
6. Hong, D., Niu, Y.L., Xiao, Y.Y., Sun, P., Kong, J.J., Guo, P.Y., Shao, F.L., Wang, X.H., Duan, M., Xue, Q.Q., Gong, H.M., Chen, S., 2018. Origin of the Jurassic-Cretaceous intraplate granitoids in Eastern China as a consequence of paleo-Pacific plate subduction. Lithos 322, 405-419.
附件下载: