黔东南从江九星铁金矿床磁铁矿地球化学特征及其地质意义  

Chemical Characteristics of Magnetite in Jiuxing Fe-Au Deposit, Congjiang County, Southeastern Guizhou Province, China and it's Geological Significance

作　　者：刘永坤[1,2] 张均[1] 刘安璐[1] 申浩原 仲文斌 陈葛成 

机构地区：[1]中国地质大学(武汉),湖北武汉430074 [2]贵州省地矿局102地质大队,贵州遵义563003

出　　处：《矿物学报》2015年第4期502-508,共7页Acta Mineralogica Sinica

基　　金：贵州省地勘基金(黔财建[2013]212号);中国地质调查局项目(1212011220414)

摘　　要：九星铁金矿位于扬子陆块与华夏陆块过渡带上,矿体产于甲路一段与二段间的翁浪—地虎滑脱蚀变带中,是一个小型规模矿床。电子探针、主-微量和稀土元素分析发现,主量元素方面,磁铁矿中K2O、Mg'O、P2O5和Ca'O含量甚微,而Fe'Ot含量与Si'O2、A12O3、Cr2O3和V2O3含量呈明显的负相关关系;微量元素方面,V、Cr、Zn、Cu、Sb、W、Pb和Bi等元素富集;稀土元素方面,具有富轻稀土、Eu负异常(δEu均值为0.77)和Ce弱负异常(δCe均值为0.95)特征。相关参数的判别和对比结果显示,九星铁金矿床的形成经历了成矿环境从弱氧化环境向还原环境过渡的过程,其成因属于热液型。Jiuxing Fe-Au deposit is located in the transition zone between the Yangtze block and Cathaysia. Ore bodies are produced in the ＂Wenglang-Dihuo＂ type slip in the alteration zone, which is between the section 1 and section 2 of the Jialu Formation. Jiuxing deposit is a small type Fe-Au deposit. The major, trace and rare earth elements of magnetite from Jiuxing deposit were analyzed by using EPMA and ICP-MS. Results show that the contents of K2 O, Mg O, P2O5 and Ca O are low, with a obvious negative correlations of Fe Ot and Si O2, A12O3, Cr2O3 and V2O3. The V, Cr, Zn, Cu, Pb, Bi, Sb and W are enriched in magnetite. Contents of REE in magnetite are low, whereas LREE are more enriched than HREE. The mean δEu value is 0.77 and average δCe value is 0.95. These suggest that the formation of magnetite in Jiuxing Fe-Au deposit undergone from weak oxidation to reduction environment. The ore genesis of Jiuxing deposit belongs to the hydrothermal type.

关 键 词：磁铁矿 元素地球化学特征 九星铁金矿床 

分 类 号：P618[天文地球—矿床学]