摘要
东昆仑夏日哈木超大型岩浆镍钴硫化物矿床的工业价值,不仅取决于矿石中Co、Ni的含量,还取决于钴和镍关键金属的赋存状态和分布规律。笔者利用全自动矿物分析系统钻孔样品分析,确定Co和Ni在样品中有2种赋存状态:独立钴、镍矿物和含Co、Ni矿物。对钴、镍金属矿物进行原位主、微量元素分析发现,Co在钴、镍金属矿物中含量由高到低为:辉砷钴矿>砷镍矿、方硫铁镍矿、镍黄铁矿>红砷镍矿、磁铁矿>磁黄铁矿、黄铜矿;Ni在钴、镍金属矿物中含量由高到低为:砷镍矿、红砷镍矿>硫铋镍矿、方硫铁镍矿、镍黄铁矿>辉砷钴矿>磁铁矿、磁黄铁矿、黄铜矿。选择钻孔中体积分数占比最高的磁黄铁矿、镍黄铁矿和黄铜矿,进行原位核-边微量元素及面扫描分析发现,Co、Ni在镍黄铁矿和黄铜矿单颗粒尺度上是均一分布的,两种矿物的Co/Ni值变化不大,表明矿物没有受到热液作用影响。然而,Ni在磁黄铁矿中分布不均一,并且矿物的Co/Ni值变化较大,表明磁黄铁矿对热液作用更为敏感。矿物原位主、微量元素分析结果显示,镍黄铁矿中的Co、Ni含量与镍、钴独立矿物接近,远超岩体中其他含钴、镍金属硫化物。因此,含Ni黄铁矿的矿石应作为选冶重点关注对象。
The industrial value of the Xiarihamu giant Ni-Co sulfide deposit in the East Kunlun orogenic belt,is not only depends on the content of Co and Ni elements in the minerals,but also on the occurrence state and spatial distribution pattern of Co and Ni elements.In this study,Borehole samples were analyzed by TESCAN Integrated Mineral Analyzer.It was determined that Co and Ni elements occur as isolated minerals and sulfurarsenic mineral compositions.In-situ analysis of major and trace element analysis of the metal minerals in the Xiarihamu Ni-Co deposit have been carried out.The contents of Co in the minerals from high to low are as follows:cobaltine>maucherite,bravoite,pentlandite>niccolite,magnetite>pyrrhotite,chalcopyrite;the contents of Ni in the minerals from high to low are as follows:maucherite,niccolite>bismuthite,bravoite,pentlandite>cobaltine>magnetite,pyrrhotite and chalcopyrite.Pyrrhotite,pentlandite and chalcopyrite were chosen for LA-ICP-MS trace elements and elements mapping analysis,the Co and Ni were uniform in pentlandite and chalcopyrite in the single particle mineral scales,and there are no obvious changes observed in Co/Ni ratios,these indicating that hydrothermal process did not affect the Co and Ni contents of pentlandites and chalcopyrites.However,Ni is heterogeneous in pyrrhotite,and the Co/Ni ratios varies from 0.01 to 0.63,indicating that the pyrrhotite is more sensitive to hydrothermal processes.In situ major and trace element analysis show that the contents of Co and Ni in pentlandite are close to that of isolated Co-Ni minerals,and far exceeds that of pyrrhotites and chalcopyrites.Therefore,the ore containing pentlandite has the most potential for Co and Ni resource exploretion.
作者
赵达成
王美乐
李章志贤
魏雅洁
李华
王金宏
张晓琪
ZHAO Dacheng;WANG Meile;LI Zhangzhixian;WEI Yajie;LI Hua;WANG Jinhong;ZHANG Xiaoqi(State Key Laboratory of Continental Dynamics,Department of Geology,Northwest University,Xi’an 710069,Shaanxi,China;Qinghai Provincial Survey Bureau,MNR Technology Innovation Center for Exploration and Exploitation of Strategic Mineral Resources in Plateau Desert Region,Xining 810000,Qinghai,China;Qinghai Yellow River Mining Co.,Ltd.,Xining 810008,Qinghai,China)
出处
《西北地质》
CAS
CSCD
北大核心
2023年第6期17-40,共24页
Northwestern Geology
基金
国家自然科学基金项目“中国西部典型岩浆铂族元素和钴金属超常富集成矿动力学”(91962212)
西北大学2023年度大学生创新创业训练计划项目“东昆仑造山带夏日哈木Ni-Co-(PGE)金属分布和赋存状态”(S202210697247)
西北大学地质学系国家基础科学人才培养基金“青海夏日哈木Ni-Co-PGE岩浆矿床关键金属分布和赋存状态研究”(XDCX2021-03)
陕西省教育厅项目“北秦岭松树沟铬铁矿矿床成矿机制研究”(15JK1760)联合资助成果。
