青藏高原东南部前寒武纪结晶基底的形成与演化

The crystalline basement is ancient component of orogens, and records the formation and reworking histories of continental crust and orogen. This application project will carry out a petrological, geochemical and geochronological study for the Precambrian crystalline basements exposed in the Amdo, Chayu and NamTso areas of the southeastern Tibetan Plateau. The aims of this project are to reveal the component, formation time and environment, metamorphic, deformation and magmatic events of the crystalline basements, and multiple reworking during the Neoproterozoic, Paleozoic and Mesozoic orogenesis, to reconstruct their origin and tectonic affinity, to constraint the Paleozoic tectonic regime of the northern margin of the Gondwana supercontinent, and to establish the Mesozoic terrane assembly and tectonic modal of the southern Tibetan Plateau. The relevant results will provide new insights into the contribution of the Pre-Cenozoic composite orogeny to the formation and growth of the Tibetan Plateau.

结晶基底是造山带的古老物质组成，记录了大陆地壳和造山带的形成与再造历史。本申请项目拟通过岩石学、地球化学和年代学研究，查明青藏高原东南部安多、察隅和纳木错地区前寒武纪结晶基底的组成、形成年代、形成环境、变质-岩浆事件序列，及其在新元古代、早古生代和中生代的再造过程，探讨青藏高原南部拉萨、安多和羌塘地体的起源和构造归属，限定冈瓦纳超大陆北缘古生代的构造格局，青藏高原南部中生代的地体拼合过程与构造演化模型，揭示前新生代造山作用对青藏高原形成和生长的重要贡献。

青藏高原东南部的前寒武纪结晶基底是造山带的古老物质组成，记录了大陆地壳和造山带的形成与再造历史。本项目对青藏高原东南部前寒武纪结晶基底进行了岩石学、地球化学和年代学研究，初步查明了青藏高原东南部前寒武纪结晶基底的组成、形成年代、形成环境、变质–岩浆事件序列，及其在新元古代、早古生代和中生代的再造过程，探讨青藏高原南部拉萨、安多、羌塘地体和喜马拉雅带的起源和构造归属，限定了青藏高原南部中生代的地体拼合与构造演化过程。相关成果为青藏高原的形成与生长提供了新的信息。