Investigation of the sulfur speciation during chalcopyrite leaching by moderate thermophile Sulfobacillus thermosulfidooxidans

The surface sulfur speciation of chalcopyrite leached by moderately thermophilic Sulfobacillus thermosulfidooxidans was investigated by employing scanning electron microscopy (SEM), X-ray diffraction (XRD) and sulfur K-edge X-ray absorption near edge structure spectroscopy (XANES), accompanying with the leaching behavior elucidation. Leaching experiment showed that there was an optimum range of the redox potential for chalcopyrite dissolution. Leaching products were found accumulating during the leaching process, which might be jarosite according to the XRD analysis. The sulfur K-edge spectra indicated that chalcocite might be the intermediate sulfur compound under a critical redox potential, which might explain the existence of optimum range of the redox potential and provide an evidence for the two-step leaching model of chalcopyrite at low Eh. In addition, the results of sulfur K-edge spectra showed jarosite would accumulate on mineral surface, which might be the main component of the passivation layer.     

扬子地台西南缘朱家坝辉绿岩地球化学特征及其地质意义

近年来在扬子西缘大量的早—中元古代岩浆岩证据显示扬子地台内形成的断陷盆地及早中元古代岩浆岩与全球性的Columbia超大陆裂解事件有着密不可分的联系。这种联系主要表现在区内早中元古代的岩浆岩地球化学特征上。为了探讨武定裂陷槽朱家坝辉绿岩的地球化学特征及其意义,以12块朱家坝辉绿岩的地球化学分析数据为基础,在分析了其主微量和稀土元素的特征之后发现朱家坝辉绿岩w(SiO_2)为44.16%～48.08%,w(K_2O+Na_2O)为3.54%～4.26%,在化学成分上属于钙碱性岩石;其稀土元素的总量为183.1×10^-6～206.91×10^-6,LREE/HREE=1.44～1.96,表明在其形成过程中发生了明显的地壳混然或者是岩浆分异作用,其化学成分基本可以反映出岩浆源区的化学组成特征。基于此,对朱家坝辉绿岩进行了源区性质、构造环境和可能的成因机制探讨,认为朱家坝辉绿岩形成于拉张环境之中,很有可能是在昆阳裂谷形成初期形成,其岩浆来源于较富集的地幔源区,形成过程中几乎没有地壳物质参与。     

Fluid unmixing/immiscibility as an ore-forming process in the giant REE–Nb–Fe deposit, Inner Mongolian, China: Evidence from fluid inclusions

The giant Bayan Obo REE–Nb–Fe deposit consists of replacement bodies hosted in dolomite marble made up of magnetite, REE fluorocarbonates, fluorite, aegirine, amphibole, calcite and barite. Two or three phase CO₂-rich, three phase hypersaline liquid–vapor–solid, and two phase liquid-rich inclusions have been recognized in mineralized fluorite and quartz samples. Microthermometry measurements indicate that the carbonic phase in CO₂-rich inclusions is nearly pure CO₂. Fluids involving in REE–Nb–Fe mineralization at Bayan Obo might be mainly of H₂O–CO₂–NaCl–(F–REE) system. Coexistences of brine inclusions and CO₂-rich inclusions with similar homogenization temperatures give evidence that immiscibility happened during REE mineralization. An unmixing of an original H₂O–CO₂–NaCl fluid probably derived from carbonatitic magma. The presence of REE-carbonates as an abundant solid in fluid inclusions shows that the original ore-forming fluids are very rich in REE, and therefore, have the potential to produce economic REE ores at Bayan Obo.     

Constraining the hydrocarbon expulsion history of the coals in Qinshui Basin, North China, from the analysis of fluid inclusions

From the comprehensive study on the homogenization temperatures and the occurrence of fluid inclusions in the framework minerals of the strata between or above the Carboniferous–Permian coals in the Qinshui basin, Shanxi, three stages are predicted of hydrocarbon expulsion from the coals. Combined with the known history of basin evolution, it is deduced that the expulsion of hydrocarbons happened during the J₁ (210–180 Ma), the early K₁ (150–130 Ma) and K₂E₁ (110–60 Ma). In the early stage, the coals produced and discharged coal-generated oils. The average GOI value of four sandstone samples is relatively high, as they have been exposed to high paleo-oil saturation in the strata between or above the coals. The biomarker compositions of oil-bearing fluid inclusions are similar to those of extracts from the coals, and so it is concluded that those oils were derived from the same family of the coals.     

“老脚印”对自升式钻井平台插桩滑移的影响研究

渤海海域自升式钻井平台作业频率高,在同一区块多次插桩作业情况多,为自升式平台插桩作业带来严重的滑移风险。通过建立常用的两种类型桩靴的有限元分析模型,采用模拟计算和对比分析的研究方法,对在“老脚印”不同距离位置插桩时,桩基土体的塑性破坏特性、运移规律及桩靴所受侧向滑移力进行了模拟研究,得出了在不同土质条件下,桩基土和桩靴的受力特性及规律,分析了不同位置的“老脚印“对自升式平台插桩滑移风险的影响。     

Ocean Ridge Granite and Its Geochemical Characteristics in Western Qinghai—Xizang Plateau

In our work,ocean ridge granite,i.e., Oytan plagiogranite massif,was discovered in western Qinghai-Xizang plateau.It intruded into the basic lava of the Oytag ophiolite suite and it was formed a little later than the (ultra)mafic rocks of the Oytag ophiolite suite.The Oytang plagiogranite possesses the geochemical characteristics of mantle-source granite and was formed in the “supre-subduction zone”(SSZ)ocean ridge environment,like the ocean ridge granite of Troodos,Cypus.     

富钴结壳生长过程中铁锰氧化物矿物组合的变化

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凶国矿小核心，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FM15比FPE06低得多，可能反映了FM15在该层形成时Co通量较低，而该层在FN12中不存在，反映了区域环境的较大差异，在FN12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。     

Magnetic interactions possessing point group symmetry and their application to ruby

By utilizing the magnetic interactions possessingC _3v symmetry, the author has deduced the general expressions for theg-factors, zero-field splitting and effective magnetic moment of the ground singlet orbital state in d³-complex. For ruby (Al₂O₃: Cr³⁺) the results are in good agreement with experiments: theoretical values:g _‖ =1.9835;g _⊥=1.9876; 2D=?0.3731 cm^?1;μ _‖ =3.857β;μ _⊥=3.861β; experimental values:g _‖ =1.9840±0.006,g _⊥=1.9867±0.0006, 2D=?0.3831±0.0002 cm^?1,μ=3.8?3.9β.     

试论不同力学性质的断裂构造的富水部位及富水性

众所周知,断裂构造与地下水的关系相当密切。尤其是碳酸盐类岩石,岩溶极为发育并富含地下水,其原因在很大程度上与成岩以后的断裂构造有关。因此,研究不同力学性质的断裂构造的富水部位及富水性对于寻找地下水和查清矿区及各类工程的水文地质条件等,均有重要意义。     

番禺地区病险水库地质特点及加固对策

广州市番禺区目前尚在发挥效益的水库有15座,其中12座水库存在病害隐患,急需除险加固。基于工程地质勘察与评估工作,查明了辖区病险库的地质特点：坝身质量较差、坝基存在渗漏及渗透破坏问题、软基沉降变形和饱和砂土地震液化问题等,探讨了整险加固的工程措施,如加高加固大坝、防渗处理、抗地震液化加固等。结果为辖区病险水库整治提供技术支持,对国内类似水利工程整险加固有较好的参考价值。