冀东地区金厂峪和峪耳崖金矿床成矿岩体差异性研究:来自锆石U-Pb和原位微量元素的证据  

Characteristics of Metallogenic Intrusions of Jinchangyu and Yuerya Gold Deposits in Eastern Hebei Province:Constraints from Zircon U-Pb and In Situ Trace Elements

作　　者：张娟 王福睿 ZHANG Juan;WANG Fu-rui(Hebei GEO University,Shijiazhuang 050031,China)

机构地区：[1]河北地质大学河北省战略性关键矿产资源重点实验室,河北石家庄050031

出　　处：《河北地质大学学报》2021年第5期1-9,共9页Journal of Hebei Geo University

基　　金：河北省高等学校科学技术研究项目(QN2019144)。

摘　　要：冀东地区大规模金成矿作用与中生代花岗质岩浆活动在时空和成因上联系密切,但这些金矿床含矿岩浆的物理化学条件研究目前还很薄弱。选取金厂峪和峪耳崖金矿床,通过锆石U-Pb测年方法厘定金厂峪金矿床与矿体密切共生的钠长岩的成岩年龄为191.9±3.8 Ma,与成矿时代具有一定的耦合性。通过LA-ICP-MS分析金厂峪钠长岩和峪耳崖花岗岩的锆石原位微量元素,二者均富集重稀土,亏损轻稀土,具Ce正异常和Eu负异常及较大的Ce ^(4+)/Ce ^(3+)值,说明这两种成矿岩体结晶时均处于较高的氧化状态。因此推测高氧逸度可能为冀东地区金矿床成矿岩体的重要特征。The large-scale gold mineralization in eastern Hebei is closely related to the Mesozoic granitic magmatism in time,space and genesis.However,the study of physical and chemical conditions of these magma is still weak.In this paper,the Jinchangyu and Yuerya gold deposits are selected to study the characteristics and differences of intrusions associated with mineralization.According to the zircon U-Pb dating method,the diagenetic age of albitite closely associated with ore body in Jinchangyu gold deposit is 191.9±3.8 Ma,which has a certain coupling with the metallogenic age.LA-ICP-MS analysis of in situ trace elements of zircons from JinChangYu albitite and Yuerya granite shows that both of them are enriched in HREE and depleted in LREE,with positive Ce anomaly and negative Eu anomaly as well as large Ce ^(4+)/Ce ^(3+)values.These results indicate that the two ore-forming intrusions are in a high oxidation state during crystallization,and high oxygen fugacity may be an important characteristic of the metallogenic intrusions of the gold deposits in eastern Hebei.

关 键 词：锆石U-PB 锆石原位微量元素 成矿岩体 金矿床 冀东 

分 类 号：P571[天文地球—矿物学]