和田河与克里雅河流域不同类型沙物质的地球化学探讨

本文通过对和田河和克里雅河流域不同类型沙物质的矿物和化学成分研究,揭示了河流沙、沙丘沙和地层沙的矿物成分和化学成分存在的差异,指出这种差异是有关元素及化合物(或矿物)在不同环境下具有不同地球化学行为的结果。     

Chemical composition of saline and subsaline lakes of the northern Great Plains,western Canada

The northern Great Plains of Canada stretch from the Precambrian Shield near Winnipeg, Manitoba, westward for ∼1,700 km to the Rocky Mountains foothills. This vast region of flat to gently rolling terrain contains a very large number of salt lakes. Major ion chemical data on ∼500 of them are available. Although the average brine (salinity, 37 ppt) is a Na⁺−SO₄ ²⁻ type of water, the lakes exhibit a wide range of salinities and ionic compositions. This diversity is confirmed by Q-mode cluster analysis; it identified thirteen major water chemistry types. Most ions display distinct trends, both spatially and with increasing salinity. All dissolved components increase with increasing salinity, but at different rates. The relative proportions of Ca²⁺ and HCO₃ ⁻+CO₃ ²⁻ ions show a strong decrease with increasing brine salinity, whereas SO₄ ²⁻ ions increase with increasing salinity. The ionic proportions of Na⁺, Mg²⁺, K⁺ and Cl⁻ exhibit no significant relationship with salinity. R-mode factor analysis of the lake water chemistry, combined with selected environmental parameters, identifies groundwater composition, climate, and the elevation of the lake within the drainage system as most important in controlling brine chemistry and salinity on a regional basis. Variability in source of ions, reaction processes and products are undoubtedly key factors in helping to explain brine chemistry of an individual basin or variation from a local perspective, but these factors are generally poorly understood and not quantified on a regional basis. Palliser Triangle Global Change Project Contribution Number 3.     

甘肃西成矿田铅锌矿床的成矿物质来源探讨

本文系统地研究了甘肃省西成矿田铅锌矿床的地层地球化学和铅同位素地球化学特征,得出了该区成矿金属物质主要取自基底地层而不是含矿层的新认识。     

On the distribution of physical and chemical particle properties in the atmospheric aerosol

Consideration of sources and growth dynamics of aerosols has led to the conclusion that there may be a distribution or variation of chemical composition and physical structure among atmospheric aerosol particles as a function of size, and within a narrow size range as well. A mathematical representation of these particle properties in terms of an additional dimension to the number size distribution is described. Examples of the relevance of this aspect of aerosol characterization for physical and chemical processes in the atmosphere are discussed. A review of the available techniques shows that several methods are available which can and have provided quantitative results on the distribution of particle properties. Examples of data from the literature have been selected and are presented as three-dimensional distributions illustrating the wide range of particle properties which may exist in narrow size intervals. An evaluation of these results reiterates the value of taking the distribution of particle properties in the atmosphere into account for sampling and modeling purposes.     

冀东迁安地区太古代片麻杂岩的地球化学和演化

曹庄片麻杂岩包括35亿年的表壳岩及三个不同时期的复期正片麻岩。水厂片麻杂岩包括水厂表壳岩及侵入其中的淡花岗岩和紫苏花岗岩,后者年龄为26.5亿年。     

Nd-Sr isotopic and trace element study of rocks and fluids from the continental deep drilling Project (KTB), Germany

Geochemical analyses were interpreted on the dominant lithological units and on a deep crustal fluid from the Continental Deep Drilling Project (KTB) Pilot Hole, situated at the western margin of the Variscan Bohemian Massif. The biotite gneiss (from 384 m depth) shows a rare earth element pattern very similar to the European shale composite with Nd model ages of 940 Ma (CHUR) and 1.4 Ga (DM). The lamprophyre dike in the upper profile (1549 m), a nepheline and olivine normative basalt, is geochemically and isotopically similar to rocks from the Tertiary Central European Volcanic Province. The lower metabasite sequence (3575–4000 m), with an intrusion age of approximately 500 Ma, is made up primarily of highly metamorphosed subalkalic olivine basalts. The geochemical characteristics of the metabasites are a (La/Yb)_N of 5–10, an La concentration of 20–50 times chondrite as well as (⁸⁷Sr/⁸⁶Sr)_i of 0.7035–0.7038 and _Nd(T) of 4–6. These values suggest a depleted mantle source for the igneous precursors, evolving by assimilation-fractional crystallization processes with up to 25% of upper crust into the ultramafic, basaltic, and intermediate rock types of the metabasite sequence. The strong geochemical and chronological similarities between the KTB metabasites and rocks from the Münchberg Massif suggest that these units belong to the same lithological complex. The high salinity as well as the radiogenic ⁸⁷Sr/⁸⁶Sr ratio of 0.709413 in the KTB fluid from 4000 m depth might be the result of migrating fluids reacting with the regional Permo-Mesozoic evaporite deposits, followed by extensive Sr isotopic exchange with the upper crust.     

博兴县浅层地下水水化学演化分析研究

通过对比分析博兴县20多年来的浅层地下水水质监测资料,研究总结了该区浅层地下水水化学类型及主要水化学组分的动态演化特征。结果表明,该区大部分地段浅层地下水水化学类型较为稳定,7个长期监测点中仅有2个监测点阳离子或阴离子类型呈现出明显改变,有4个监测点部分水化学组分含量呈现出上升趋势,造成这些变化的原因主要与南部地下水降落漏斗的形成导致北部咸水向南部补给有关。     

胶东地区玲珑金矿田东风矿床Rb-Sr同位素年龄及其地质意义

胶东是我国最重要的金矿集中区之一,其成矿背景和成矿作用过程在全球金矿中独具特色（Goldfarb and Santosh,2014）。著名的玲珑金矿田就位于胶东西北部“招莱金矿带”东端,包括玲珑、九曲、大开头、东风和东山等矿段或矿区。本文研究的东风金矿床位于玲珑矿田东南部,该区自20世纪80年代末期发现致矿异常,圈定成矿预测区以来,科研工作者对此进行了有关研究,徐晓璐等（2013）等以东风矿床为例,运用Surpac软件对矿床数据库和矿体品位分布模型的建立进行了研究;冯涛等（2009）等对东风金矿171号脉的矿床地质特征进行了研究;对东风金矿区成矿规律,姜维明等（2002）等进行了初步探讨。但是,对该矿床的成矿时代等研究相对薄弱,本文选取东风矿床与金矿关系密切的黄铁绢英岩,对其进行Rb-Sr同位素分析,以期查明东风金矿床成矿时代等问题,为深入地了解和认识该矿床的成因和成矿作用提供新的依据。     

吉林长安堡钼(铜)矿床成矿时代及物质来源:来自辉钼矿Re-Os同位素证据

吉林省中东部地区地处中国东北部陆缘、兴蒙造山带的东段,目前已探明大中型钼矿床十余座,矿床类型有斑岩型、矽卡岩型和石英脉型。长安堡斑岩型钼(铜)矿床是吉林中部地区新发现的一座大型斑岩型矿床,成矿年代学研究工作至今尚未开展。本文在矿床地质特征研究的基础上,对矿区辉钼矿进行了Re-Os同位素体系的定年研究,获得辉钼矿模式年龄值为167.3±2.4~168.7±2.4 Ma,加权平均值为168.0±1.0 Ma(MSWD=0.16),等时线年龄为168.0±6.2 Ma(MSWD=0.42),表明长安堡钼(铜)矿床形成于中侏罗世,属中国北方燕山期大规模钼成矿期成矿,结合已发表的钼矿床高精度年代学数据,认为吉林中东部地区的钼成矿作用发生在早-中侏罗世(167~196 Ma)。矿区辉钼矿的Re含量介于25.17~34.80μg/g,平均值为29.54μg/g,指示了成矿物质具有壳幔混源、且更偏壳源特征,为准确认识该矿床的成矿物质来源提供了进一步的制约。这些成果对于研究吉林地区钼矿资源的成矿规律提供了科学依据。     

Microstructures and their implications for faulting processes –Insights from DGLab core samples from the Gulf of Corinth

We have examined microstructures, mineralogical composition, geochemical alteration, and texture of four selected fault rock samples from the Deep Geodynamical Laboratory (DGLab) Gulf of Corinth project using optical microscopy, cathodoluminescence microscopy (CL), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and synchrotron X-ray diffraction measurements. The fault core is composed of red and gray clayey gouge material and surrounded by a damage zone of brecciated limestones. Pressure solution features, calcite veins and calcite clasts in the breccia and gouge material attest the presence of paleo-fluids and fluid-driven mass transfer during deformation. Differences in CL-colors between the matrix and calcite vein cement and inside the vein cement suggest repeated infiltration of fluids with different composition from various sources (formation water and meteoric water). Twin lamellae densities estimated in calcite veins are used as paleo-piezometer. The deduced differential stress is ∼140 ± 70 MPa for the older vein generation and appears to be higher than stress for the youngest veins (45 ± 23 MPa). In spite of the relatively small clay content in both samples, newly formed clay minerals have been observed in gray as well as red clayey gouge material. Differences between gray and red clay gouge material are found in fault rock composition, porosity and clay fabric. The proportion of chlorite in the red gouge is significantly less than that in the gray gouge whereas the initial porosity is significantly higher than in the gray gouge material. The detection of a well-oriented clay fabric in red clay gouge samples is unique in comparison to other major fault zones.