内蒙古准苏吉花铜钼矿床稀土元素特征及对成矿作用的约束  

Characteristics of Rare Earth Elements and Constraints on Mineralization from Zhunsujihua Copper-Molybdenum Deposit in Inner Mongolia

作　　者：席明杰[1] 马生明[1] 朱立新[2] 弓秋丽[1] 

机构地区：[1]中国地质科学院地球物理地球化学勘查研究所,河北廊坊065000 [2]中国地质科学院,北京100037

出　　处：《中国稀土学报》2013年第4期503-512,共10页Journal of the Chinese Society of Rare Earths

基　　金：国土资源部公益性行业专项项目(201111008);中国地质科学院物化探研究所基本科研业务费项目(AS2010P06;AS2011P04)资助

摘　　要：准苏吉花高-中温热液脉型铜钼矿床是近年来中蒙边境新发现的众多中型铜钼矿床之一,矿体主要赋存在二叠纪花岗闪长岩中,仅少量产于宝力高庙组变质粉砂岩中,多呈透镜状产出,具尖灭再现现象。矿床稀土元素组成特征表明:花岗闪长岩和闪长岩脉稀土配分模式相似,表现为强负Eu异常和极弱或无负Ce异常,为同源岩浆演化的产物。变质粉砂岩稀土组成与岩浆岩截然不同。辉钼矿矿石稀土元素组成大致可分为两组:一组矿石表现为明显的负Eu异常,Ce表现为由弱异常过渡为无异常的特征,与矿区花岗闪长岩稀土组成相似;另外一组矿石表现为弱负Eu异常和极弱负Ce异常,介于花岗闪长岩与变质粉砂岩稀土元素组成之间,暗示成矿过程中岩浆热液与地层之间发生了水/岩交换。说明区内成矿物质一部分来源于花岗闪长岩,另一部分来源于宝力高庙组变质粉砂岩。矿石δEu值指示矿石沉淀于高温、低氧的相对还原环境。As one of the numerous copper-molybdenum deposits detected on the frontiers of China and Mongolia in recent years,the orebody of Zhunsujihua high-mesothermal vein Cu-Mo deposit which appears in lenticular shape and pinch out reproduction phenomenon,mainly occurred in the Permian granodiorite,only a small mount occurred in metamorphic siltstones of Baoligaomiao formation.The REE characteristics of the deposit indicated that the granodiorite and diorite vein lineation displayed the similar REE patterns,characterized by a strong negative Eu anomaly and extremely weak or no Ce anomaly,which is the product of comagmatic evolution.The REE compositions of metamorphic siltstones were completely different from magmatic rocks.The molybdenite ore could be divided into two groups depending on the REE composition： one had a similar REE compositions to the granodiorite of the mining area,showing obvious negative Eu anomaly,while Ce performed the feature from weak negative anomaly to none,and the other had a weak negative Eu anomaly and very weak negative Ce anomaly and the REE compositions between granodiorite and metamorphic siltstone,which suggested that water-rock exchange takes place between magmatic hydrothermal and formation in the process of mineralization.The result showed that the metallogenic materials were not only derived from granodiorite,but also originated in metamorphic siltstones of Baoligaomiao formation.The value of δEu instructed that the ore deposits in a relatively reducing environment of high temperature and hypoxia.

关 键 词：稀土元素 成矿作用 铜钼矿床 准苏吉花 

分 类 号：P611.13[天文地球—矿床学] P595[天文地球—地质学]