• 责任者：Wang Xingjun (School of Geosciences and Resources ; China University of Geology ; Beijing 10083 ; China) ; Wang Genhou
• 刊名：Geology in China
• 出版年：2013
• 卷期：40(6)
• 关键词：蛇绿岩 ; ophiolite ; 西藏 ; Tibet
• 页码：p.1749-1761
• 图表：10 illus., 2 tables, 37 refs.
• 分类号：0801
• issnNo：ISSN1000-3657
• isbnNo：CN11-1167/P

     Located at the westernmost end of Yarlung Zangbo suture zone, the Bangguori-Boku ophiolite belt is composed of NW-striking Bangguori ophiohte and Boku melange 128 km in length and 5-10 km in width. Bangguori ophiohte consists of harzburgite and lherzohte comprising ohvine （Fo=85.2～88.0, 86.6 on average）, enstatite （Mg# =89.3～94.3, 91.2 on average）, and diopside （Mg#=89.3～94.3, 93.1 on average）, characterized by high Al2O3 （0.96%～2.10%） and Ti （173～261μ g/g）, close to the trace element content of MOR mande rock, and depletion of REE with ∑REE being 0.33～0.71 times that of chondrite. Moreover, major and trace element characteristics indicate that Bangguori ophiohtes are restites resulting from 6%～12% partial melting of the primitive mande. Boku melange consists of groundmass of slate and silty slate, and rock mass of peridotite, gabbro, siliceous rock, sandstone and hmestone. Studies show that Baoguori-Boku ophiohte belt was formed during Late Cretaceous, as evidenced by isotope dating of Bangguori ophiohte and radiolarians fossils from the silicohte rock mass of Boku melange. The results obtained by the authors demonstrate that Bangguori-Boku ophiohte belt resulted from Neotethys ocean subduction, and Bangguori ophiohte represents the residuum of Neotethys ocean hthosphere and belongs to the typical MOR-type ophiohte.