地质与勘探2017，Vol.53Issue(3)：495-507,13.
内蒙古双尖子山银多金属矿床花岗斑岩年代学、地球化学特征及构造意义
Zircon U-Pb Dating and Geochemistry of the Granite Porphyry from the Shuangjianzishan Silver Polymetallic Deposit in Inner Mongolia and Tectonic Implications
摘要
Abstract
This paper presents a series of studies on the granite porphyry from the Shuangjianzishan silver polymetallic deposit,including dating of zircon SHRIMP U-Pb,and analysis of major elements and trace elements.The results show that the granite porphyry,a product of active magmatic activity in the southern Dahinggan Mountains during the early Cretaceous,has an age of (133.4--± 1.2) Ma on average.It contains 68.81％ ～70.05％ of SiO2,and small amounts of MgO and TiO2.The K2O/Na2O value is between 0.97 to 1.27,indicating a feature of slight potassium-rich.The A/CNK is between 0.94 and 1.12,which belongs to metaluminous-weak peraluminous series.The lithophylic elements (LILE) such as Rb,Th,U and K are rich,while HFSE such as Sr,P,and Ti are deficit.The total amount of race earth content ΣREE is normal.δEu is between 0.55 to 0.62.Eu is medium negative anomalous.We conclude that the Shuangjianzishan silver polymetallic deposit belongs to the multi-period magmatic hydrothermal deposits.160Ma and 133 Ma are probably the two peak periods of magmatic activity,respectively.The granite porphyry formed under the condition of the intraplate environment of late orogenic and post-orogenic extension.The resulted asthenospheric material upwelling due to the deep break of the subducting plate of Mongolia-Okhotsk is the main mechanism of the intraplate extensional environment during the early Cretaceous in southern Dahinggan Mountains.关键词
锆石/SHRIMP U-Pb定年/构造背景/花岗斑岩/双尖子山/内蒙古Key words
zircon/SHRIMP U-Pb dating/tectonic setting/granite porphyry/Shuangjianzishan/Inner Mongolia分类
天文与地球科学引用本文复制引用
顾玉超,陈仁义,贾斌,鞠楠..内蒙古双尖子山银多金属矿床花岗斑岩年代学、地球化学特征及构造意义[J].地质与勘探,2017,53(3):495-507,13.基金项目
国土资源公益性行业科研专项(编号:201311018)资助. （编号:201311018）
