河北高寺台超基性杂岩体中铬铁矿特征及地质意义  

Characteristics and geological significance of chromitein Gaositai ultrabasic complex,Hebei Province

作　　者：赵金召 董培培 郭菁华 王帅 张夏炜 宋珈璐 Zhao Jinzhao;Dong Peipei;Guo Jinghua;Wang Shuai;Zhang Xiawei;Song Jialu(Hebei Province Collaborative Innovation Center for Strategic Critical Mineral Research,Hebei GEO University,Shijiazhuang 050031,China;Land Resources Exploration Center of Hebei Bureau of Geology and Mineral Exploration and Development(Hebei Emergency Rescue Center for Mines and Geological Disasters),Shijiazhuang 050081,China)

机构地区：[1]河北地质大学河北省战略性关键矿产研究协同创新中心,河北石家庄050031 [2]河北省地质矿产勘查开发局国土资源勘查中心(河北省矿山和地质灾害应急救援中心),河北石家庄050081

出　　处：《资源环境与工程》2025年第2期171-177,共7页Resources Environment & Engineering

基　　金：国家科技基础资源调查专项项目“战略性新兴产业矿产潜在矿产资源结构及分布图研编”(2022FY101704);国家自然科学基金项目“内蒙古迪彦庙蛇绿岩带前弧玄武岩组合及其成因”(441972061);河北地质大学第十九届学生科技基金科研项目(KAG202304)。

摘　　要：高寺台超基性杂岩体位于华北克拉通北缘冀北基性—超基性杂岩带,具环状分带,由中心向外依次分布纯橄岩、辉橄岩、辉石岩,其中纯橄岩中产出铬铁矿,属于层状铬铁矿类型。采集高寺台超基性杂岩体中未蚀变的铬铁矿开展矿相学和地球化学研究,探究其形成的构造环境。研究表明,铬铁矿成分均一,Cr_(2)O_(3)含量为51.34%~53.40%,均值为52.45%;Al_(2)O_(3)含量为6.95%~7.56%,均值为7.21%;TFeO为25.41%~30.33%,均值为27.47%;铬指数Cr^(#)为82.47~83.48,均值为82.99;镁指数Mg^(#)为35.07~47.24,均值为42.61。高寺台超基性杂岩体中的铬铁矿具有与岛弧构造环境相似的地球化学特征,其地质背景和发育特征与津巴布韦大岩墙铬铁矿相似,推测其形成于俯冲下的拉张环境,并具有较好的找矿潜力。Gaositai ultrabasic complex is located in northern Hebei basic-ultrabasic complex belt on the northern margin of North China Craton.The complex has annular zoning,from the center to the outside,it is distributed in the order of dunite,pyroxenite and pyroxenite.The chromite produced in dunite belongs to the type of layered chromite.The unaltered chromite in the Gaositai ultrabasic complex was collected to carry out mineralogical and geochemical studies to explore the tectonic environment of its formation.The results show that the composition of chromite is uniform,and the content of Cr_(2)O_(3)ranges from 51.34%to 53.40% with an average of 52.45%,the content of Al_(2)O_(3)ranges from 6.95%to 7.56%with an average of 7.21%,the content of TFeO ranges from 25.41%to 30.33%with an average of 27.47%.The chromium index Cr^(#)is 82.47-83.48,with an average of 82.99.The magnesium index Mg^(#)is 35.07-47.24,with an average of 42.61.The chromite in the Gaositai ultrabasic complex has similar chemical characteristics of island arc tectonic environment.Its geological background and development characteristics are similar to the chromite in the Large Dyke of Zimbabwe.It is speculated that it is formed in the extensional environment under subduction and has good prospecting potential.

关 键 词：铬铁矿 拉张环境 高寺台超基性杂岩体 

分 类 号：P578.4[天文地球—矿物学]