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对纳木错西缘念青唐古拉岩群中表壳岩和变质深成体进行了锆石阴极发光、背散射电子成像和SHRIMP锆石U-Pb年龄测定, 其形成年龄下限由奥长花岗岩锆石U-Pb年龄限定为787±9 Ma,上限由花岗岩锆石U-Pb年龄限定为748±8 Ma. 这表明念青唐古拉岩群的形成时代与高喜马拉雅结晶岩系形成时代相当, 它们共同组成了印度地盾北部新元古代活动大陆边缘的弧-盆体系. 拉斑玄武岩和花岗岩中继承锆石给出947~1766 Ma的中元古代年龄. 正的eNd(t)值表明, 念青唐古拉岩群中基性岩来源于亏损地幔并受到古老地壳物质的混染, Nd模式年龄和继承锆石U-Pb年龄均指示新元古代时期拉萨地块存在中元古代基底.
Zircon cathodoluminescence, backscattered electron imaging and SHRIMP U-Pb dating of zircons were carried out for the crustal and metamorphic deep bodies in the Nyainqentanglran group in the western margin of the Namur fault. The lower age of the zircons formed by zircon U- The Pb age is limited to 787 ± 9 Ma and the upper limit is defined by the zircon U-Pb age of the granite as 748 ± 8 Ma, indicating that the age of the Nyainqentanggrany formation was comparable to that of the Himalayan crystalline rock series that together formed India The Neoproterozoic arc-basin system along the continental margin of the northern Neoproterozoic belt in the northern part of the earth shield shows that the inherited age of the Mesoproterozoic from 947 to 1766 Ma in tholeiitic basalt and granite shows a positive eNd (t) The mafic rocks originated from the depleted mantle and were contaminated by ancient crustal materials. Nd age and inherited zircon U-Pb ages both indicated the existence of Mesoproterozoic basement in the Lhasa block during the Neoproterozoic.