南秦岭陡岭杂岩新元古代变质作用及年代学研究

以南秦岭造山带陡岭杂岩中新元古代变质作用的发现为基础，选择变泥质岩和石榴斜长角闪岩为主要研究对象，通过详细的岩相学观察和变质反应结构分析来划分变质演化阶段；在电子探针和全岩化学分析基础上，使用常规的地质温压计及THERMOCALC相平衡计算方法来确定岩石的P-T稳定区域和演化轨迹；通过不同类型岩石的LA-ICP-MS锆石U-Pb和角闪石40Ar-39Ar同位素定年，进一步限定陡岭杂岩的变质时代。据此探索扬子陆块北缘新元古代的大地构造环境和构造演化过程。

Neoproterozoic metamorphism is newly recognized in the Douling Complex of South Qingling orogen. In this proposal metapelites and garnet-bearing amphibolites from the Douling Complex will be selected to be the primary research objects. Metamorphic stages will be identified on the basis of petrographic observations and metamorphic reaction textures. With the combination of electron microprobe analyses and whole rock compositions, the metamorphic conditions and P-T path of the rocks will be determined using conventional geothermobarometry and THERMOCALC phase equilibrium calculations. Metamorphic ages will be constrained by LA-ICP-MS zircon U-Pb and hornblende 40Ar-39Ar dating on a variety of rock types in the Douling Complex. These data will be used to discuss the tectonic setting and evolution of the north margin of Yangtze block during the Neoproterozoic.