芬兰科密铬铁矿床研究新进展  

New progress of the research on the Kemi chromitite deposit in Finland

作　　者：张伟波[1,2] 刘翼飞[1] 王丰翔[1,3] 陈秀法 何学洲[2] 于瑞[2] ZHANG Weibo;LIU Yifei;WANG Fengxiang;CHEN Xiufa;HE Xuezhou;YU Rui(Institute of Mineral Resources,CAGS/Key Laboratory of Metallogeny and Mineral Assessment,MNR,Beijing 100037,China;Development Research Center,China Geological Survey,Beijing 100037,China;Hebei University of Geosciences,Shijiazhuang 050031,Hebei,China)

机构地区：[1]中国地质科学院矿产资源研究所/自然资源部成矿作用与资源评价重点实验室,北京100037 [2]中国地质调查局发展研究中心,北京100037 [3]河北地质大学,河北石家庄050031

出　　处：《地质通报》2020年第5期746-754,共9页Geological Bulletin of China

基　　金：中国地质调查局项目《“一带一路”资源与环境信息采集及产品开发》(编号:DD20190455)。

摘　　要：芬兰科密铬铁矿床是欧洲规模最大的铬铁矿床。对该矿床的地质背景、矿床特征、矿床成因及找矿标志进行了总结。结果表明,该矿床与古元古代层状超镁铁质杂岩体具有密切的时空分布关系,杂岩体内的铬铁矿床具典型的层状堆积特征,矿层延伸稳定。由于Cr/Fe值较低,该矿床矿石品位在世界同类矿床中属偏低水平。同位素年代学证据表明,其形成于古元古代早期(2.44 Ga),是由卡累利阿造山作用诱发多期次岩浆侵入活动并与新太古代基底岩层发生混染作用形成的。科密铬铁矿床属于层状铬铁矿床,其地质特征与中国目前已发现的豆荚状或似层状铬铁矿床存在一定区别。The Kemi deposit is the largest chromite deposit in Europe.The authors have summarized its geological setting,orebody features,ore genesis and ore indicators in this paper.The deposit is hosted by early Proterozoic Kemi layered complex,which strikes northeastward along the Svecokarelidic Perapohja schist belt.The chromite deposit in the complex has typical layered accumulation characteristics and the ore layers extend steadily.Due to the low Cr/Fe ratio in ore,its grade belongs to low level among similar ore deposits in the world.Isotopic geochronology evidence suggests that the mineralization age is 2.44 Ga,indicating that the metallogenesis of chromitite deposit occurred in early Paleoproterozoic.During the Karelia orogeny,the chromitite was deposited when the input of magma into the Kemi intrusion was contaminated by salic material from the underlying basement complex.This magma was mixed with the fresh input of primitive magma,resulting in chromite saturation.The chromite crystals were formed during mixing in a plume.The Kemi deposit is a layered type chromitite deposit,and its geological features are different from features of podiform type or stratoid type chromite deposits discovered in China.

关 键 词：科密 铬铁矿床 地质特征 找矿标志 芬兰 

分 类 号：P618.33[天文地球—矿床学]