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111.
Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) is well characterized by the in-situ, real time, lower limit of detection and high space resolution, etc. Therefore, it is more excellent in the analysis of trace element for varied minerals in comparison to other micro-zone analysis technologies. Magnetite as a common mineral from different deposits and rocks has been focused on chemical compositions by researchers worldwide. In fact, as the insignificant matrix effect for most elements in magnetite, analysis results could be calculated effectively against Fe-rich silicate glass as the reference material. Therefore, researches on trace element distribution of magnetite have been developed rapidly in recent years, and it has a wide application prospect in reflecting the condition of ore-forming, discriminating different deposit types and indicating prospecting exploration. Comparing varied previous discrimination diagrams about magnetite via collecting trace element data from available literatures based on 25 deposits, we found that there was an urgent need for further detailing and reexamining the boundary of fields representing different genetic types, and it was vital for interpreting the data through carefully petrographical observation before analysis. In addition, we discussed several complex physicochemical factors, which would influence the element concentration of magmatite in igneous and hydrothermal processes, such as melt/fluid composition, temperature, cooling rate, pressure, oxygen fugacity, sulfur fugacity and silica activity. In magma stage, Magnetite’s components are closely related to melts composition and differentiation, while fluid features would also significantly change magnetie's components. Furthermore, there is serious interference for discriminating the genesis of magnetite because of late stage fluids and equilibrium again in subsolidus condition. This paper reviewed the developments of trace elements analysis by LA-ICP-MS and important applications about magnetite in mineral deposit so that unique thoughts for the research on mineralization and ore-forming processes could be obtained. 相似文献
112.
Xue Song Wang Jun Jun Ren Hai Jie Lu Lei Zhu Fei Liu Qian Qian Zhang Juan Xie 《洁净——土壤、空气、水》2010,38(12):1131-1136
Magnetite nanoparticles were applied to remove Ni(II) from aqueous solutions as a function of pH, contact time, supporting electrolyte concentration, and analytical initial Ni(II) concentration. The highly crystalline nature of the magnetite structure with diameter of around 10 nm was characterized with transmission electron microscopy (TEM) and X‐ray diffractometry (XRD). The surface area was determined to be 115.3 m2/g. Surface chemical properties of magnetite at 25°C in aqueous suspensions were investigated. The point of zero charge (pHzpc) was found to be 7.33 and the intrinsic acidity constants (${\rm p}K_{{\rm a}1}^{{\rm s}} $ and ${\rm p}K_{{\rm a}2}^{{\rm s}} $ ) were found to be 9.3 and 5.9, respectively. The surface functional groups were investigated with Fourier transform‐infrared spectroscopy (FTIR) as well. Batch experiments were carried out to determine the adsorption kinetics and mechanism of Ni(II) by these magnetite nanoparticles. The adsorption process was found to be pH dependent. In NaCl solutions, Ni(II) adsorption increased with increasing ionic strength while in NaClO4 solutions, Ni(II) adsorption exhibited little dependence on the ionic strength of the solution. The adsorption process better followed the pseudo‐second order equation and Freundlich isotherm. 相似文献
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矿区金、铜、钼矿化与碱性斑岩相关,向阳组碎屑岩是主要矿源层及赋矿地层,北东向响水断裂控矿,近东西向次级断裂及层间断裂为储(容)矿构造。多种条件耦合成矿。 相似文献
114.
云南兰坪中排李子坪铅锌矿矿床成因 总被引:1,自引:0,他引:1
铅锌矿产于下白垩统景星组下段泥质粉砂岩、钙质砂岩和中侏罗统花开左组上段砂岩夹薄层泥灰岩介壳灰岩中,脉状、透镜状、层状、似层状等产出。NNE向断裂的交叉夹持部位的旁侧派生次级断裂及层间破碎带是主要容矿构造,矿床成因为沉积-中低温热液改造构造控矿型。 相似文献
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荷叶塘陨石是1998年降落的一块普通球粒陨石。本文在对荷叶塘陨石的岩石学和矿物化学特征分析的基础上,划分了荷叶塘陨石的岩石类型和次级岩石类型。荷叶塘陨石橄榄石的Fa值在0.6-48.8之间,平均值为23.2,PMD为60.1%;低钙辉石的FS值在0.6-49.0之间,平均值为9.1,PMD为97.5%。结合橄榄石Fa值的PMD与次级岩石类型关系、橄榄石中的Cr含量、铁纹石中富Ni颗粒的数量密度等,综合判断荷叶塘陨石的化学-岩石类型为L3.3,由此表明该陨石是一块热变质程度非常低的L型非平衡普通球粒陨石。 相似文献
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三维地质建模和可视化概念最早是由加拿大Houlding在1993年提出的。三维地质建模是指采用适当的数据结构在计算机中建立能反映地质构造的形态和各要素之间的关系以及地质体物理、化学属性空间分布等地质特征的数学模型。Minexplorer软件集高效快捷、地质分析自动化、二维GIS制图与三维可视化为一体,能对原始勘探资料和地质编录成果数字化,有效管理、分析地质勘探多元数据,可构建理想的三维勘探辅助决策模型,科学计算矿床资源储量、实现储量动态管理和计算机辅助制图。 相似文献
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