太平洋东马里亚纳海盆多金属结核成因及品位控制因素  

Genesis and grade control factors of polymetallic nodules in the East Mariana Basin of Pacific

作　　者：曹德凯 任向文[1,2,3] 石学法 

机构地区：[1]国家海洋局第一海洋研究所,山东青岛266061 [2]海洋沉积与环境地质国家海洋局重点实验室,山东青岛266061 [3]青岛海洋科学与技术国家实验室海洋矿产资源评价与探测技术功能实验室,山东青岛266071

出　　处：《海洋学研究》2017年第4期76-86,共11页Journal of Marine Sciences

基　　金：国家自然科学基金项目资助(41176057;40806027);国际海底区域研究开发"十二五"课题资助(DY125-13-R-06)

摘　　要：本文选取东马里亚纳海盆与CC区中国多金属结核合同区西区的多金属结核样品,采用ICPOES、ICP-MS以及XRD等测试方法对结核表层进行了地球化学与矿物学分析,并探讨了东马里亚纳海盆结核成因以及其主要成矿元素含量的控制因素。结果表明,结核具备水成型结核的主、微量元素特征,并受到成岩作用的影响。结核上下表层各元素含量差异明显,上表层Fe、Co、P等多数主量元素及∑REYs含量均高于下表层,而Mn、Cu、Ni等元素含量在下表层明显增加。根据结核矿物学以及海洋环境特征,并结合前人数据统计分析认为,东马里亚纳海盆结核样品中Mn、Ni、Cu、Co、Fe、Ce的品位主要受控于Mn矿物组成、底层海水溶解氧和表层海水初级生产力,La、Y等稀土元素品位还受到洋中脊热液活动的制约。Geochemical and mineralogical analysis was carried out by ICP-OES,ICP-MS and XRD for the polymetallic nodules collected from the East Mariana Basin and western portions of the China Contract Zone.The genesis and grade control factors of main economic elements in the nodules from the East Mariana Basin were explored.The results show that the nodules are mainly hydrogenetic type in major and∑REYs elements concentrations and to some extent,their mineral compositions are influenced by diagenetic processing.The contents of Fe,Co,P and other main elements and ∑REYs in the upper surface layer of nodules are higher than those in the lower surface layer,while the contents of Mn,Cu and Ni are significantly higher in the lower surface layer.Based on the characteristics of mineralogy and marine environment as well as the statistical analysis data in this research and other literatures,it can be concluded that the grades of Mn,Ni,Cu,Co,Fe and Ce of nodules from East Mariana Basin are mainly controlled by Mn mineral and the dissolved oxygen of bottom currents as well as the primary productivity of surface seawater,while the grades of La,Y and other rare earth elements are also subjected to the hydrothermal activities from East Pacific Rise.

关 键 词：多金属结核 表层分析 稀土元素 控制因素 

分 类 号：P618.2[天文地球—矿床学] P736.3[天文地球—地质学]