【摘要】 富钴结壳的矿物学研究是一个难点。本文运用电子探针微区分析结合X射线衍射和矿相显微镜观察的综合方法对富钴结壳中的铁锰氧化物矿物组合及其组分变化进行了研究。研究发现 ,富钴结壳是从与胶状粘土类混合共沉积开始生长的 ,结壳内部的韵律层和柱状构造也是始于粘土层终于粘土层的 ;铁锰团粒的核心一般是较纯的水羟锰矿小核心 ,可能是在生物媒介作用下在水体中形成后沉降叠积的。FM、FPE海山结壳的中层存在一较纯水羟锰矿层 ,但该层中Co含量FM1 5比FPE0 6低得多 ,可能反映了FM1 5在该层形成时Co通量较低。而该层在FN1 2中不存在 ,反映了区域环境的较大差异。在FN1 2火焰状构造亚带存在Mn氧化物和Fe氧化物的极度分异现象 ,可能反映了结壳形成环境的重大变化。更多还原

【Abstract】 Mineralogical study on Co\|rich crust is a hard nut to crack. This paper deals with the mineral assemblages and the compositional variations of Fe\|Mn oxides by means of electron probe analysis, X\|ray diffraction and reflex microscope. It is found that the growth of Co\|rich crust took place by sedimentation of the Fe\|Mn oxides blending with colloidal clay minerals on the naked rock of the seamount. The Fe\|Mn oxide rhythms including polar structure of Co\|rich crust also start with sedimentation of the Fe\|Mn oxides blending with the colloidal clay minerals and stop growth by increasing quantity of clay minerals, which shows the role of environmental variation and sedimentation rate during its formation. The core of a Fe\|Mn grain would generally be little pure vernadite particle, which may have been formed by the medium of microbe in seawater and then settled down for accumulation. There is a fairly pure layer of vernadite in the middle layer of Co\|rich crusts of FM and FPE seamounts, and the content of Co may be greatly different from one region to another. The content of Co in FM15 is much lower than that in FPE06, which may indicate a low Co flux in that period of time the layer was formed. The layer doesn’t exist at all in FN12, which shows a great regional environment variation. In the flame\|shaped subzone of FN12, Fe and Mn oxides were detached extremely, which may be a reflection of great environmental changes in the formation of crust.更多还原