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为探讨贵州下寒武统黑色岩系中铂族元素物质来源及钼-镍、钒多金属形成的沉积环境与成矿作用,在钼-镍、钒多金属层及其顶底页岩、底部硅质岩中采集样品测试分析。通过对样品中金、铂族元素含量(质量分数)及其地球化学特征值研究,结果表明：黑色岩系中金及铂族元素含量显示协同变化特征;Pd富集,Ru、Ir亏损明显,Pt、Rh、Os基本持平或略有变化;样品的原始地幔标准值标准化模式配分曲线从Os、Ru、Rh、Ir、Pt到Pd大致呈“W”型,配分曲线略呈左倾,总体上呈现w(Pd)>w(Pt)>w(Os)>w(Rh)>w(Ru)>w(Ir)的变化关系;黑色岩系铂族元素来源与正常海水及海底热水喷流作用关系密切,地外来源可能性极小;黑色岩系钼-镍、钒多金属层中铂族元素的富集存在单独成矿作用或成矿作用的叠加,而且在钒多金属层内局部存在分层或条带分异。 相似文献
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贵州遵义黑色页岩铂族金属富集特点及富集模式 总被引：28，自引：1，他引：28
文章通过贵州遵义下寒武统牛蹄塘组黑色页岩剖面和矿石的PGE分析以及矿石物相分析，研究了PGE在黑色页岩中的富集特点和富集模式。发现：（1）PGE只在黑色页岩底部Mo-Ni金属层中富集；（2）金属层中PGE富集与Mo、Ni硫化物和黄铁矿呈正相关关系，与总碳（C总）代表的有机质和炭质无关，矿石PGE含量随硫化物总量呈增高的趋势；（3）Mo-Ni-PGE矿石PGE原始地鳗标准化配分曲线呈“W”型，富集高熔点元素Os、Rh和低熔点元素Pt、Pd；黑色页岩和条带状黄铁矿夹层配分曲线略呈Pt、Pd富集型，两者有较明显的差别。因此，Mo-Ni-PGE金属硫化物富集层是黑色页岩沉积早期迅速叠加的一次海底热水喷流沉积作用的结果。 相似文献
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黔西地区峨眉山玄武岩（东岩区）铂族元素地球化学特征 总被引：7，自引：0，他引：7
利用同位素稀释-等离子体质谱(ICP-MS)方法测定了黔西水域、威宁等地的东岩区峨眉山玄武岩的铂族元素含量。结果表明，相对于原始地幔，东岩区峨眉山玄武岩的铂族元素发生了较强的分异作用，Os、Ir、Ru、Rh亏损，Pd、Pt发生富集，相对配分模式为Pd-Pt富集型；经球粒陨石及原始地幔标准化的铂族元素配分模式为向左陡倾斜型，具有陡的正斜率，Pd／Ir显著高于原始地幔、球粒陨石、原始上地幔等，而与地幔低度熔融形成的N-MORB、大陆拉斑玄武岩等接近，表明峨眉山玄武岩的物质来源为上地幔熔融程度偏低的玄武岩浆。 相似文献
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贵州天鹅山下寒武统黑色岩系化学地层初步研究 总被引：2，自引：0，他引：2
华南下寒武统黑色岩系“多元素富集事件”受世人瞩目。贵州遵义天鹅山下寒武统牛蹄塘组剖面的元素地球化学测试表明,黑色岩系存在贵金属元素、稀土元素及其他微量元素的异常富集,绝大多数较上覆、下伏地层含量为高。元素地球化学特征显示,元素的来源并非地外,而是海底含矿热卤水沿深大断裂而来,“热”的来源为地内火山喷溢。黑色岩系形成时期的沉积环境为一种干燥气候的较深浅海的还原环境。据古地温判定,黑色岩系属低温成岩成矿作用。 相似文献
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湘西北下寒武统黑色岩系是中国南方下寒武统黑色岩系的重要组成部分,富含钒镍钼等多金属元素。文中对湘西北下寒武统黑色岩系钒镍钼矿进行了微量元素研究,研究区内Ni、Cd、Mo、Sb、V、Zn、W、Ba等元素特别富集,高含量的Sb和Ba表明其为热水沉积;Mo含量极高说明其为缺氧的还原环境;高的V/（V+Ni）、V/Cr、Ni/Co以及δU值表明其沉积环境为缺氧环境;高的 U/Th表明本区有热水沉积作用;稀土元素配分模式、Ce和Eu异常及La/Yb Ce/La和La/Yb ΣREE图解投点表明其沉积环境为还原环境,并有热水沉积作用。可见黑色岩系形成于缺氧环境,热液活动为其提供了丰富的热液来源。 相似文献
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东太平洋CC区多金属结核铂族元素（PGE）地球化学及其意义 总被引：12，自引：2，他引：12
文章采用火试金分离富集法和等离子发射光谱(ICP_MS)测定了东太平洋CC区多金属结核中PGE和Au元素的含量,结果显示:结核中PGE相对于洋壳明显富集,尤其是Pt含量较高,wPt平均值为100.90×10-9。各种类型的多金属结核PGE和Au的球粒陨石配分曲线及有关参数非常一致,均表现为Pt正异常和Pd负异常,显示其中PGE和Au具有相似的来源。多金属结核与海底海山富钴结壳PGE配分模式及特征元素比值对比表明,两者PGE可能具有相同的来源,可能主要来源于海底玄武岩的水岩反应,部分来源于铁陨石,而并非主要来自海底热液及正常海水。 相似文献
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通过野外地质调查资料、X衍射、主量及铂族元素测试分析,研究川南马边地区五峰-龙马溪组页岩的矿物学、主量元素地球化学特征和铂族元素组成特征。川南马边长河碥五峰-龙马溪组页岩有机碳TOC平均含量为2.47%;矿物成分主要由石英和黏土矿物两大类构成,石英平均含量37.95%,黏土矿物平均含量为40.2%;页岩SiO2平均含量为52.90%,Al2O3平均含量为11.47%;铂族元素总量在1.5～11.9 ng/g之间,平均值为5.16 ng/g。川南马边地区五峰-龙马溪组页岩铂族元素均以Pt与Pd含量高为特征,其中Pd平均含量为3.15 ng/g,Pt平均含量为1.48 ng/g。铂族元素碳质球粒陨石配分模式为Pt-Pd型,Pd含量约为Pt含量的2.12倍。剖面中富有机质页岩比贫有机质页岩更加富集铂族元素,铂族元素的富集可能与生物活动有关;黏土矿物含量与铂族元素含量呈负相关关系,铂族元素并未呈吸附态吸附在颗粒表面,黏土矿物的增加反而稀释了铂族元素含量。川南马边长河碥五峰-龙马溪组铂族元素并非来源于地外物质,可能来自地幔,且发生了明显分异,其富集程度在正常海洋沉积物范围内。 相似文献
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奥地利安东帕有限公司 《岩矿测试》2009,28(3):306-306
最新的流行病学研究表明,空气中较高浓度的悬浮细颗粒可能对人类的健康有不利的影响。根据该项研究显示,由于心脏病、慢性呼吸问题和肺功能指标恶化而导致死亡率的升高与细尘粒子有关。这些研究结果已经促使欧盟于1999年4月出台了限制空气中二氧化硫、二氧化氮、氧化氮、铅和颗粒物含量的法案(1999/30/EC),对各项指标包括对可吸入PM10颗粒的浓度提出了新的限制性指标。PM10颗粒是指可以通过预分级器分离采集的气体动力学直径小于10μm的细颗粒。目前研究的兴趣重点逐步偏向PM2.5这些更细微颗粒物,PM2.5这种颗粒物对健康有明显的不利影响。在欧盟指令2008/50/EC中,对PM10和PM2.5都提 相似文献
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A catastrophic rockslide-debris flow in Wulong, Chongqing, China in 2009: background, characterization, and causes 总被引：7，自引：3，他引：4
Qiang Xu Xuanmei Fan Runqiu Huang Yueping Yin Shengshan Hou Xiujun Dong Minggao Tang 《Landslides》2010,7(1):75-87
On June 5, 2009, a catastrophic rockslide-debris flow occurred at the crest of the Jiweishan Mountain in Wulong, Chongqing,
China. Approximately five million cubic meters of limestone blocks slid along a weak interlayer of bituminous and carbonaceous
shale. The source mass descended from the upper part of the slope rapidly, crossing a 200-m wide and 50-m deep creek in front
of it. Blocked by the opposite steep creek wall, the sliding mass changed its direction and traveled a further 2.2 km along
the creek in debris-flow mode, finally forming a large accumulation zone with an average depth of 30 m. This is one of the
most catastrophic rockslide events in recent years in China. It buried 12 houses and the entrance of an iron mining tunnel
where some 27 miners were working inside. Ten people died, 64 missing, and eight wounded. Immediately after this disaster
happened, the government organized an expert team to assist the rescue work. As one of the geological experts, the author
did a lot of field investigations and collected first-hand information. Multi-methods including the remote sensing, 3D laser
scanning, geophysical exploration, and numerical modeling were used for analyzing the characteristics and the triggering mechanism
of the Wulong rockslide. The preliminary investigation results reveal that this rockslide with poor geological conditions
was mainly induced by the gravitation and the karst effect and also affected by the previous mining activities. The research
in this paper is meaningful and useful for further research on such kind of rockslides that are geologically similar to the
Wulong rockslide. 相似文献
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Joseph Clancy White 《Contributions to Mineralogy and Petrology》1993,113(4):524-532
The textural relationships and structural states of optically isotropic labradorite from the Manicouagan, Quebec, impact structure have been examined by light (optical) and transmission electron (TEM) microscopy. Two distinct diaplectic glasses have been recognized based on their contrasting morphology, timing and the inferred modes of formation. The earliest isotropic bands and grain-scale isotropism (maskelynite) optically exhibit a gradational,in situ transformation from crystalline plagioclase with preservation of relict textures (twins, grain boundaries). The same transformation from crystalline to amorphous structure is observed in TEM to occur heterogeneously at scales on the order of the unit cell. The progressive transformation of optical properties reflects an increase in the volume fraction and eventual coalescence of these amorphous units. This maskelynite-type diaplectic glass is interpreted to form in the solid-state directly from crystalline material during the compressional phase of the shock wave. The other isotropic material occurs in spatially discrete tensiongashes and planar deformation features (PDFs) that overprint the maskelynite-type glass. This second type of diaplectic glass (PDF-type) is developed homogeneously within a given glass band and exhibits sharp crystal-glass boundaries, in contrast to the gradational boundaries of the maskelynite-type glass. PDF-type glass is interpreted to form by melting in tensional release zones during passage of the rarefaction wave. These observations emphasize the ability of naturally shocked rocks to preserve subtle evidence of variations in the shock process from highly transient events. 相似文献
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S. Viswanathan K. Surya Prakash Rao B. Mahabaleswar 《Journal of the Geological Society of India》2013,82(6):621-627
Komatiites are mantle-derived ultramafic volcanic rocks. Komatiites have been discovered in several States of India, notably in Karnataka. Studies on the distribution of trace-elements in the komatiites of India are very few. This paper proposes a simple, accurate, precise, rapid, and non-destructive wavelength-dispersive x-ray fluorescence (WDXRF) spectrometric technique for determining Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb, Ba, Pb, and Th in komatiites, and discusses the accuracy, precision, limits of detection, x-ray spectral-line interferences, inter-element effects, speed, advantages, and limitations of the technique. The accuracy of the technique is excellent (within 3%) for Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Zr, Nb, Ba, Pb, and Th and very good (within 4%) for Y. The precision is also excellent (within 3%) for Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb, Ba, Pb, and Th. The limits of detection are: 1 ppm for Sc and V; 2 ppm for Cr, Co, and Ni; 3 ppm for Cu, Zn, Rb, and Sr; 4 ppm for Y and Zr; 6 ppm for Nb; 10 ppm for Ba; 13 ppm for Pb; and 14 ppm for Th. The time taken for determining Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb, Ba, Pb, and Th in a batch of 24 samples of komatiites, for a replication of four analyses per sample, by one operator, using a manual WDXRF spectrometer, is only 60 hours. 相似文献
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Natural Hazards - Despite the application of various methods to calculate uncertainty in flood vulnerability assessments, the challenge of uncertainty remains. The main purpose of this study was to... 相似文献
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Xiaoyu ZHAO Wuyi WANG Hairong LI Fujian FENG Lizhen WANG 《中国地球化学学报》2006,25(B08):80-81
Brick-tea-type fluorosis is a peculiar endemic disease in China, which had been discovered in minority areas of western China since 1980, and distributed mainly in Tibet, Inner Mongolia, Gansu, Xinjiang, Qinghai and parts of Sichuan Province. The prevalence rate of fluorosis in Tibetan and Mongolian nationality people was higher. Epidemiological investigation showed that fluorosis morbidity and degrees were different in different brick-tea drinking areas, and it was probably caused by drinking various kinds of brick tea from different regions. Therefore, we collected 33 samples of brick tea from six provinces where minority nationalities were accustomed to drinking a large quantity of brick tea. F concentrations were determined by the combustion hydrolysis-ion selective electrode method. The results showed that among the brick teas, the F concentrations ranged from the minimum 74.1 mg/kg in Yunnan Province to the maximum 991.2 mg/kg in Sichuan Province. Besides, there was a great difference among the various kinds of brick tea, and F concentrations decreased in the order of Kang brick tea, Green brick tea, Black brick tea, Mi brick tea, Fu brick tea, Chitsu ping tea, Puerh tea, and Tuo tea. The average F concentration in brick teas was 431.92 mg/kg. 相似文献
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日本北海道音调津的球状石墨 总被引：1，自引：0，他引：1
本文利用光学显微镜、X射线衍射仪、透射电镜等手段对日本北海道音调津球状石墨的成因、结构等进行研究,认为日本北海道音调津球状石墨中除了石墨外,还存在镍黄铁矿﹑黄铜矿﹑磁黄铁矿等金属硫化物矿物。通过透射电子显微镜观察发现音调津石墨中大部分是椭圆状石墨颗粒,高分辨晶格条纹主要是非晶态结构,但是同时也发现了结晶良好的石墨。高结晶度石墨的存在可能是在硫化物Fe-Ni-Cu的触媒作用下形成的。天然球状石墨的微结构和性状研究对天然石墨的形成和开发应用有重要意义,对新型碳材料的制备技术有重要科学意义。 相似文献