东天山新元古代强过铝质花岗岩的发现对中天山构造带北缘的约束  

Discovery of Neoproterozoic peraluminous granites in the eastern Tianshan orogen and its constraints on the northern margin of the Middle Tianshan tectonic belt

作　　者：李平[1] 高晓峰[1] 孟勇[1,2] 孙少珍 LI Ping;GAO Xiaofeng;MENG Yong;SUN Shaozhen(Xi'an Centre of China Geological Survey,CGS,Xi'an,Shaanxi 710054,China;Xining Natural Resources Investigation Center,Xining,Qinghai 810012,China;Xi'an Northwest Nonferrous Geophysical and Geochemical Exploration Co.Ltd,Xi'an,Shaanxi 710068,China)

机构地区：[1]中国地质调查局西安地质调查中心,陕西西安710054 [2]中国地质调查局西宁自然资源综合调查中心,青海西宁810012 [3]西安西北有色物化探总队有限公司,陕西西安710068

出　　处：《地质学报》2023年第6期1815-1827,共13页Acta Geologica Sinica

基　　金：中国地质调查项目(编号12120114015201,DD20190065,DD20221636);国家自然科学基金项目(编号42002229);陕西省自然科学基础研究计划项目(编号2023-JC-YB-268,2023-JC-ZD-15)联合资助的成果。

摘　　要：东天山小黄山花岗岩位于阿齐克库都克断裂和康古尔塔格断裂之间的构造带,为一类具有白云母、石榴子石等矿物的S型花岗岩,属于强过铝质花岗岩类。其LA-ICP-MS锆石U-Pb同位素测年结果为835.4±9.0 Ma,地球化学特征说明此花岗岩为后碰撞岩浆作用而成,属于新元古代Rodinia超大陆拼贴-裂解事件的产物。此外,该前寒武纪岩体的发现结合康古尔塔格—镜儿泉沿线出露的蛇绿岩、含蓝晶石和石榴子石的变质岩系,以及康古尔塔格断裂带南北两侧区域地层的差异,可以将康古尔塔格断裂带作为分隔中天山和北天山构造带的重要依据。Some S-type granites from the Xiaohuangshan area in eastern Tianshan orogenic belt,occurred between the Aqikekuduke fault and the Kangol fault zone.These muscovite and garnet bearing granites are strongly peraluminous rocks.The granites have a formation age of 835.4±9.0 Ma determined by zircon La-ICP-MS dating,and geochemical features show they are post-collision granites,which can be considered to be a result of magmatic activity during the Rodinia supercontinent convergence and break-up.Moreover,the discovery of Precambrian granites,ophiolite,medium-high pressure metamorphic rocks(with an assemblage of kyanite and garnet) along the zone between Kangol and Jinger Quan,and the differences of the regional strata on the both sides of the line,indicates that the Kangol fault zone can be regarded as the boundary between northern Tianshan tectonic belt and Middle Tianshan tectonic belt.

关 键 词：强过铝质花岗岩 新元古代岩浆作用 康古尔断裂带 中天山构造带 

分 类 号：P548[天文地球—构造地质学] P588.121[天文地球—地质学]