冀北锥子山花岗质岩体岩石成因及地质意义  

The Petrogenesis and Geological Significance of Granite in Zhuizi Mountain of North Hebei

作　　者：陈薇 樊玉朋 王光 张兴康 刘程远 CHEN Wei;FAN Yu-peng;WANG Guang;ZHANG Xing-kang;Liu Cheng-yuan(Hebei Institute of Geological Survey,Shijiangzhuang 050081,China)

机构地区：[1]河北省地质调查院,河北石家庄050081

出　　处：《河北地质大学学报》2020年第6期22-29,共8页Journal of Hebei Geo University

基　　金：河北省地质勘查专项资金项目“河北省围场县锥子山杂岩体成矿地质条件研究”。

摘　　要：锥子山复式岩体位于华北克拉通北缘燕辽成矿带中段,岩体主体为黑云母花岗岩,侵入时代为早—晚侏罗世和早白垩世,将其划分为四期岩浆岩。论文在前人研究的基础上对锥子山花岗岩进行了岩石学、地球化学研究。地球化学数据显示锥子山花岗岩富SiO 2(70.02%~76.39%),富K 2 O(4.06%~5.31%),贫CaO(0.32%~1.56%)等特征;A/CNK整体小于1.1,属高钾钙碱性岩系列。锥子山花岗岩富集Rb、Th、U、Zr、Hf等高场强元素,而亏损Ba、Sr、Nb、Ta、P、Ti等元素。轻重稀土分馏明显,富集轻稀土,亏损重稀土,具有显著铕负异常。锥子山花岗岩为A型花岗岩,是在中国东部构造体制大转折早期,受太平洋板块向欧亚板块俯冲以及弧后伸展作用的影响下,地壳物质部分熔融的产物。The complex rock mass of Zhuizi Mountain is located in the middle part of the Yan Liao metallogenic belt,northern margin of North China craton.The complex rock mass is subjected to biotite granite.The invasion era can be divided into four period,they are early-late Jurassic and early Cretaceous respectively.Based on the data available,the authors conducted petrological,geochemical studies of the granitoids of Zhuizi Mountain.Geochemical datas suggest that the rock is rich in SiO 2(70.02%~76.39%),K 2 O(4.06%~5.31%)but poor in CaO(0.32%~1.56%);A/CNK ratios of<1.1 suggest the rock belongs to high-K calc-alkaline series.The granite of Zhuizi Mountain is rich in Rb,Th,U,Zr and Hf,and depleted in Ba,Sr,Nb,Ta,P and Ti.The LREE and HREE is highly differentiated,and enrichment in LREE,depleted in HREE.The granite has significant Eu negative anomaly.The rock in Zhuizi Mountain is A type granite It can be inferred that the granite was originated from partial melting within the lower crust as the state of the area tectonic background is stretched when the Pacific plate Intermittently subduct to the Eurasian plate in early stage of the tectonic regime changing in eastern China.

关 键 词：岩石学 地球化学 锥子山复式岩体 

分 类 号：P571[天文地球—矿物学]