江西余干支家桥地区镁铁质岩体的LA-ICP-MS锆石U-Pb年龄、地球化学特征及其地质意义  

LA-ICP-MS Zircon U-Pb Dating and Geological Significances of Mafic Rocks in Zhijiaqiao Area of Yugan,Jiangxi Pronvince

作　　者：左祖发[1] 徐喆[1] 刘杨 黄志忠[2] 刘邦秀[1] 马振兴[3] 徐祖丰 

机构地区：[1]江西省地质调查研究院,江西南昌330030 [2]中国地质调查局南京地质调查中心,江苏南京210016 [3]江西省国土资源厅,江西南昌330025

出　　处：《东华理工大学学报（自然科学版）》2017年第4期306-313,共8页Journal of East China University of Technology(Natural Science)

基　　金：中国地质调查局项目(1212010610607)

摘　　要：对江西余干支家桥地区镁铁质岩体进行了年代学、岩石学和地球化学研究,主量元素特征和微量元素分析结果显示,铁镁质岩具富钙、富铝、富铁、富镁、贫碱特征,岩体为钙碱性系列的镁铁质堆积岩,岩浆基性程度较高;A/NCK均大于1,属于铝质基性-超基性岩类。镁铁质岩体LA-ICP-MS锆石U-Pb定年法测年结果为(47.40±0.5)Ma,时代属于古近纪始新世,表明该镁铁质岩体是喜马拉雅期陆内伸展作用的产物。Chronology, petrology and geochemistry study have been conducted on the mafic pluton from Zhijiaqiao area in Yugan, Jiangxi Province. The results show that it relatively rich in Ca, Al, Fe, Mg and depleted in alkali, which indicates affinity of ealc-alkaline series of the marie accumulative rock. Whereas to the A/NCK, it displays more than 1 and locates in aluminous-mafic ultramafic domain. LA-ICP-MS dating of U-Pb method on single zircon shows the marie pluton form 47.40 ± 0.5 Ma, Eocene of Paleogene, which probably associated with large scale intracontinental extension in Himalayaian.

关 键 词：镁铁质岩体 LA-ICP-MS锆石U-PB测年 古近纪始新世 余干支家桥 

分 类 号：P618.2[天文地球—矿床学]