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布青山蛇绿混杂岩位于阿尼玛卿带西段,它是由早古生代和早石炭世—早二叠世两期蛇绿岩组成的复合蛇绿混杂岩带。蛇绿岩中的变质橄榄岩以方辉橄榄岩为主,高镁,∑REE是球粒陨石的0.2～0.65倍,HREE是球粒陨石的0.28～0.32倍,属亏损的大洋岩石圈地幔。早古生代蛇绿岩中辉长岩、辉绿岩和玄武岩等镁铁质岩主要具N-MORB性质,少量具T-MORB性质。早石炭世—早二叠世蛇绿岩中玄武岩也主要具N-MORB性质、少量具T-MORB性质。它们均形成于洋中脊环境。本区曾存在成熟的早古生代洋盆和古特提斯洋盆,有更复杂的构造演化史。
The cloth green hill ophiolitic mélange is located in the west section of Animaqing belt, which is a composite ophiolitic melange belt composed of Early Paleozoic and Early Carboniferous-Early Permian ophiolite. The metamorphic peridotites in ophiolites are mainly hyerite, with high magnesium, ΣREE is 0.2 ~ 0.65 times that of chondrite, and HREE is 0.28 ~ 0.32 times chondrite, which is a depleted oceanic lithospheric mantle. The mafic rocks such as gabbro, diabase and basalts in Early Paleozoic ophiolite are mainly characterized by N-MORB and T-MORB with few. The basalt in the Early Carboniferous-Early Permian ophiolite is also mainly characterized by N-MORB with a small amount of T-MORB. They are all formed in mid-ocean ridge environment. There are mature Early Paleozoic and Upper Tethys oceanic basins in this area, with more complicated tectonic evolution history.