摘要
对北山马鬃山地区深井正长花岗岩进行了锆石U-Pb测年和岩石地球化学研究,探讨其形成时代、岩石成因和构造背景。正长花岗岩锆石U-Pb年龄为(417.8±6.6)Ma(MSWD=6.8),形成于晚志留志—早泥盆世。岩石富硅、富钾、弱过铝质,稀土元素球粒陨石标准化配分曲线呈Eu异常不明显的右倾型,富集Rb、K、U,亏损Nb、P、Ti,岩石具有I-S花岗岩的特征,源岩为壳源成因,具有同碰撞和火山弧构造环境特征。结合区域构造背景分析认为,深井正长花岗岩为晚三叠世—早泥盆世由岛弧向同碰撞构造环境转变的产物。
In order to explore formation age,petrogenesis and tectonic background of Beihan Moutain,the zircon U-Pb geochronology and geochemistry of the Shenjing syenogranite in the Mazongshan area were studied.The zircon U-Pb age of syenitegranite is(417.8±6.6)Ma(MSWD=6.8),which was formed in the Late Silurian-Early Devonian.The rock has a characteristics of silicon-rich,potassium-rich,weakly peraluminous,the chondrite-normalized REE partition curve incline to the right with Eu anomalies of a low degree,enriched in Rb,K,U,and depleted in Nb,P,Ti,the origin of source rock is crust,the tectonic environmental is syn collision and volcanic arc.Combined with the regional tectonic background,the Shenjing syenitegranite is the product of the tectonic environment transition from island arc to syn collision in Late Triassic-Early Devonian.
作者
郭峰
王红杰
刘佳
王伟红
无
GUO Feng;WANG Hongjie;LIU Jia;WANG Weihong;无(Zhengzhou Institute of Multipurpose Utilization of Mineral Resource,Chinese Academy of Geological Sciences;National Research Center of Multipurpose Utilization of Non-metallic Mineral Resource;Key Laboratory for Polymetallic Ores′Evaluation and Utilization,Ministry of Natural Resources of the People′s Republic of China;Northwest China Center for Geosience Innovation)
出处
《现代矿业》
CAS
2020年第12期24-30,共7页
Modern Mining
基金
东天山昌吉—双沟山地区区域地质调查项目(编号:DD20190067)
长江中游黄石—萍乡—德兴矿山集中区综合地质调查项目项目(编号:DD20190269)。
关键词
正长花岗岩
锆石定年
地球化学
syenitegranite
zircon geochronology
geochemistry
