|
The history of using SEM to study surface texture of minerals is rather short,especially scarce cases are the observation of quartz in rocks of comparatively older geological ages.Therefore, surface texture of quartz grains were studied under SEM in this paper.Samples were collected from quartz-magnetite ores of the main ore-body in Mekeng Iron Deposits, Clear traces, caused by subaqueous mechanical collision, were found to be retained on these quartz grains, even though they had passed through diagenesis and... The history of using SEM to study surface texture of minerals is rather short,especially scarce cases are the observation of quartz in rocks of comparatively older geological ages.Therefore, surface texture of quartz grains were studied under SEM in this paper.Samples were collected from quartz-magnetite ores of the main ore-body in Mekeng Iron Deposits, Clear traces, caused by subaqueous mechanical collision, were found to be retained on these quartz grains, even though they had passed through diagenesis and alteration of later periods.Thus, It is clear that these quartz came mainly from terrigeneous fragments, and formed after passing through aubaqueous transportation and sedimentation in epeiric environments.Accordingly, it may be deduced that the primitive iron elements of these iron ores which paragenesis with quartz were produced from terrestrial source. The genesis of Mekeing Iron Deposits have two main different points.l)The contact replacement deposits; 2) The sedimentation-later hydrothermal superimposed alteration deposits. It is supposed that this paper may be used as an evidence to prove the sedimentary genesis of this Deposits. 运用扫描电子显微镜来研究矿物表面结构,仅有很短的历史,特别是对时代较老的地层中石英的观察,尚属寥寥.为此.我们对福建马坑铁矿主矿体的石英-磁铁矿矿石中的石英作了这方面的尝试.观察发现,尽管这些石英历经成岩作用和后期改造,但它们的颗粒表面仍保留有明显的水下机械作用的痕迹.从而说明这些石英主要来自陆源碎屑,经过水下搬运,在浅海环境沉积而成.因而有理由可以推测,与石英共生的铁矿,其原始物质也可能来自陆源. 关于马坑铁矿的成因,主要有二种不同的观点.1)、接触交代矿条;2)沉积一热液迭加改造矿床.本文可作另沉积成因的一个佐证. 福建马坑铁矿是一个大型隐伏矿床.主矿体位于下石炭统林地组之上,相当于中石炭统经畲组的层位中.矿体呈厚大似层状产出.矿体产状与围岩产状基本一致.主要金属矿物为磁铁矿,脉石矿物以透辉石、石榴石、石英为主.矿石结构以他形粒状镶嵌变晶结构为主,矿石构造以块状、浸染状、斑杂状为主,常见有条带状构造和皱纹状构造.矿石类型以石英-磁铁矿、透辉石-磁铁矿为主,并有石榴石-磁铁矿矿石. 本文是通过扫描电子显微镜的观察,对石英-磁铁矿矿石中的石英表面结构特征进行初步研究. Micro-electrophoresis is used to measure the Zeta-potential of three kinds of hydrated calcium silicates in different crystallinities and some influence fac- tors in Zeta-potential are studied. The results show that the sign and the value of Zeta-potential depend on not only the surface characteristics, but also the concentration and type of ion in the medium solution and the kinetics factions relaying the measure condition as well. In this paper, the tentative models of double-layer structure of different kinds... Micro-electrophoresis is used to measure the Zeta-potential of three kinds of hydrated calcium silicates in different crystallinities and some influence fac- tors in Zeta-potential are studied. The results show that the sign and the value of Zeta-potential depend on not only the surface characteristics, but also the concentration and type of ion in the medium solution and the kinetics factions relaying the measure condition as well. In this paper, the tentative models of double-layer structure of different kinds of hydrated calcium silicates in different medium solution are given. 本文运用显微电泳法测定了三种不同结晶度的水化硅酸钙表面的Zeta-电位,并探讨了影响其Zeta-电位的因素。实验结果表明:水化硅酸钙的Zeta-电位的符号与大小主要取决于矿物的表面结构,同时也取决于介质中离子的浓度与类型。此外,操作条件对水化硅酸钙双电层形成动力学过程密切相关。本文还给出了不同类型的水化硅酸钙在不同介质中的双电层的设想模型。 The Scanning Tunneling Microscope (STM) is a new instrument for investigations of surface structure.It directly provides three dimensional images of atomic distribution both for periodic and non-periodic structures in real space. In this paper, the author introduces the principles and applications of STM, and the investigations of surface structure of some minerals. 扫描隧道显微镜(STM)是研究表面结构的一种新型仪器,它可以直接提供出周期的或非周期结构在真实空间中原子分布的三维图象.本文介绍了扫描隧道显微镜的原理及其应用.并就笔者利用该仪器对一些矿物表面结构的探索性工作作了部分的简要介绍.
|