锗矿石和铟矿石化学成分分析标准物质研制

目前国内外没有以稀散元素锗、铟为特征元素的矿石标准物质,为了满足我国地质找矿的需求,本文采集广东省韶关凡口铅锌矿作为锗矿石候选物,广西南丹铜坑铅锌矿作为铟矿石候选物,依据国家一级标准物质技术规范,由10家实验室采用化学分析方法和现代仪器分析方法协作定值,研制了1种锗矿石标准物质(GBW07831)和1种铟矿石标准物质(GBW07833)。锗矿石标准物质定值组分为45项,铟矿石标准物质定值组分为47项,包括特征元素、共存元素、稀土元素(15项)、造岩元素和痕量元素,其中锗矿石中锗含量为21.6×10-6,铟矿石中铟含量为39.7×10-6。研制的2种标准物质丰富了我国矿石标准物质的种类,可用于锗、铟矿石化学成分分析测试的量值标准和日常质量监控。     

电感耦合等离子体质谱法(ICP-MS)测定锡矿尾砂中的铜铅锌镉铬钴镍

锡矿成分复杂,具有丰富的共生和伴生资源。锡矿尾砂中的重金属元素检测是锡矿矿区土壤风险评估和土壤环境重建的重要依据。采用硝酸-高氯酸-氢氟酸体系对样品进行了前处理,通过优化仪器条件,加入~(103)Rh标准溶液作为内标,选择~(52)Cr、~(59)Co、~(60)Ni、~(63)Cu、~(66)Zn、~(114)Cd和208 Pb作为测定同位素,建立了电感耦合等离子体质谱仪(ICP-MS)同时测定锡矿尾砂中的铜铅锌镉铬钴镍的分析方法。测定结果表明,各元素的标准曲线线性相关系数都在0.9999以上,检出限为0.003~0.12μg/L,精密度介于0.78%~3.71%之间,样品加标回收率为97.2%~103%。用本方法对锡矿石GBW07282和钨矿石GBW07240标准物质进行了分析,各元素的测定结果与标准认定值相符。     

硝酸镧为基体改进剂石墨炉原子吸收光谱法测定煤样中的铍

应用石墨炉原子吸收光谱法(GFAAS)测定煤、地球化学样品、土壤、空气等不同基质中的铍,关键是基体改进剂的选择问题。本文采用一体化平台石墨管,通过缓慢升温燃烧灰化煤炭样品,在硝酸介质中,比较了7种基体改进剂(硝酸镧、硝酸镁、硝酸铝、磷酸氢二铵、氯化钯、碳酸钙、酒石酸)对煤样中铍的增敏效果,同时探讨了基体干扰及消除的问题。实验结果表明,在2%的硝酸介质中,以硝酸镧为基体改进剂,石墨炉灰化温度提高到1100℃,原子化温度仅为2300℃时,即可消除基体中铝、铁、钙、镁、磷等共存元素的干扰。铍的浓度在0~8μg/L范围内线性关系良好,方法检出限为0.008μg/g,定量限为0.025μg/g,精密度(RSD,n=11)为1.8%~2.8%,标准样品的测定值在给定值的误差范围内。其作用机理是镧与干扰元素结合生成了热稳定的难熔、难蒸发、难解离的化合物,将铍释放出来,镧起到既提高灰化温度,又相对降低原子化温度的双重作用,消除了基体干扰的同时,又延长了石墨管使用寿命。本方法操作简单,无需对石墨管预处理,降低了检测成本,具有很强的稳定性和适应性,适用于煤中铍的测定。     

封闭溶样-电感耦合等离子体质谱法测定硫化铅矿石中40种微量元素

铅矿石在电感耦合等离子体质谱测定中,元素Pb的双电荷离子206Pb~(2+)干扰内标元素103Rh而影响其他元素的测定结果。本文建立了用~(105)Pd和~(187)Re的混合溶液为内标溶液,封闭酸溶-电感耦合等离子体质谱测定硫化铅矿石中的铍、钪、钛、铬、钴、镍、铜、锌、镓、锗、砷、锑和稀土等40种微量元素分析方法,提高了电感耦合等离子体质谱分析铅矿石中低质量的元素(质量为133Cs以下的元素)测定数据的准确度。通过大量的实验确定了该方法的检出限为0.04~5.00μg/g,对国家一级标准物质GBW07235(铅矿石)、GBW07236(铅矿石)、GBW07286(铜铅锌矿石)、GBW07287(铅锌矿石)、GBW07165(富铅锌矿石)、GBW07172(铅矿石)进行分析测定,其准确度(RE)均小于10%,加标回收率为90%~120%。     

泡塑分离富集-火焰原子荧光光谱法测定地球化学样品中的痕量金

火焰原子荧光光谱法(FAFS)测定痕量金的灵敏度好、稳定性高及线性范围广,但在测定时干扰极为严重,如果干扰元素不加以分离或扣除,对0.5ng/g以下金无法进行准确测定。本方法在传统泡塑分离富集金的基础上,研究了FAFS法测定痕量金的最佳条件:在选定仪器条件下,提出了选择低背景值(≤0.25ng/g Au)泡塑分离富集Au,采用3.0g/L硫脲-1%盐酸为解脱液可消除记忆效应,在标准系列中加入5μg/mL的Fe3+溶液扣除铁对测定金的干扰。采用本分析方法对国家标准物质GBW07805、GBW07242、GBW07244a、GBW07245a和GBW07247进行测定,相对误差≤4.7%,相对标准偏差(RSD)≤23.2%;采用FAFS法与ICP-MS法对90个原生晕样品和4个控制样品中痕量金同时进行测定,两组测定结果数统计分析的F检验值为1.23,相关系数为1.01,符合性较好,无显著性差异。本分析方法简便、快速与实用,金检出限为0.08ng/g,线性范围为0.08~500ng/g,可达3个数量级。     

标准物质镓、锗、铟、铊矿石中15种稀土元素定值方法探讨

采用微波消解-电感耦合等离子体质谱法(ICP-MS)测定了镓、锗、铟、铊矿石中的15种稀土元素,本法的检出限为(0.003~0.015)μg/g,相对标准偏差在1.11%~2.92%之间,加标回收率在95.5%~105.9%之间,通过分析国家标准物质GBW07103、GBW07106和GBW07120来验证方法的准确度,测定值和标准值吻合,表明此方法具有操作简便,检出限低,线性范围宽,精密度高,准确度好等优点,能满足岩石矿物中的稀土元素的检测要求。     

泡沫塑料吸附分离富集-电感耦合等离子体质谱法测定稀土矿石中的镓

采用电感耦合等离子体质谱法(ICP-MS)测定稀土矿石中的镓,高含量的稀土元素会造成严重的质谱干扰。本文采用聚氨酯泡沫塑料在6 mol/L盐酸介质中吸附样品溶液中的镓后,以0.5 mol/L氯化铵水浴加热解脱30 min,镓的吸附-解脱效率超过99%,稀土元素等干扰物质基本不进入解脱液中,即在富集镓的同时实现了镓与基体元素的高效分离,降低了质谱干扰。本方法检出限低(0.022μg/g),经土壤及水系沉积物标准物质验证,镓的测定值与标准值吻合(绝对偏差为0.38%~4.70%),实际稀土矿石样品的加标回收率为94.1%~100.6%,精密度(RSD)低于4%(n=12),可应用于分析一般地质样品以及稀土矿石中的镓。     

溶剂萃取—苯芴酮石墨炉原子吸收法连续测定岩石矿物中锗,铟,镓

甲基异丁基甲酮(MIBK)—苯芴酮同时萃取,利用自制的简易石墨炉平台,以镍和钒作基体改进剂测定锗、铟和镓。方法简便、快速,适合于岩石矿物中锗、铟、镓的连续测定。     

微波消解-石墨炉原子吸收光谱法测定火山灰中的痕量铅铬铜

火山灰是重要的土壤母质且易风化,铅、铬和铜是其中主要的重金属元素,火山灰风化后不可避免地进入环境中对人体健康造成危害。本研究针对火山灰样品的特点,建立了采用硝酸-氢氟酸微波消解,石墨炉原子吸收光谱法测定火山灰中痕量铅、铬、铜的分析方法。通过实验确定了灰化温度为600℃(Pb)、1000℃(Cr)和800℃(Cu),原子化温度为1800℃(Pb和Cu)、2200℃(Cr)。在优化实验条件下,测定Pb、Cr和Cu的检出限分别为3.50 ng/m L、0.92 ng/m L和1.22 ng/m L,相对标准偏差(RSD)均低于4%,加标回收率为92.8%~107.0%。本方法快速简便、准确度高、成本低。     

微波消解电感耦合等离子体质谱法测定黑色页岩中稀有稀土元素

采用硝酸-氢氟酸-过氧化氢于微波消解仪中分解样品,电感耦合等离子体质谱法测定贵州遵义地区某黑色页岩中稀有稀土元素的含量。对页岩标准物质(GBW 07107)和水系沉积物地球化学成分分析标准物质(GBW07305、GBW 07310)的分析,测定值与标准值相一致。对黑色页岩的分析结果较好,方法精密度(RSD,n=6)各元素均小于4%,加标回收率为97.9%~100.1%。方法准确度高、简单、快捷,一次溶样可同时测定多种元素。     

The terrestrial fauna of the Late Triassic Pant-y-ffynnon Quarry fissures,South Wales,UK and a new species of Clevosaurus (Lepidosauria: Rhynchocephalia)

Pant-y-ffynnon Quarry in South Wales yielded a rich cache of fossils in the early 1950s, including articulated specimens of new species (the small sauropodomorph dinosaur Pantydraco caducus and the crocodylomorph Terrestrisuchus gracilis), but no substantial study of the wider fauna of the Pant-y-ffynnon fissure systems has been published. Here, our overview of existing specimens, a few described but mostly undescribed, as well as freshly processed material, provides a comprehensive picture of the Pant-y-ffynnon palaeo-island of the Late Triassic. This was an island with a relatively impoverished fauna dominated by small clevosaurs (rhynchocephalians), including a new species, Clevosaurus cambrica, described here from a partially articulated specimen and isolated bones. The new species has a dental morphology that is intermediate between the Late Triassic Clevosaurus hudsoni, from Cromhall Quarry to the east, and the younger C. convallis from Pant Quarry to the west, suggesting adaptive radiation of clevosaurs in the palaeo-archipelago. The larger reptiles on the palaeo-island do not exceed 1.5?m in length, including a small carnivorous crocodylomorph, Terrestrisuchus, and a possible example of insular dwarfism in the basal dinosaur Pantydraco.     

The effect of water on accessory phase solubility in subaluminous and peralkaline granitic melts

The solubilities of columbite, tantalite, wolframite, rutile, zircon and hafnon were determined as a function of the water contents in peralkaline and subaluminous granite melts. All experiments were conducted at 1035 °C and 2 kbar and the water contents of the melts ranged from nominally dry to approximately 6 wt.% H₂O. Accessory phase solubilities are not affected by the water content of the peralkaline melt. By contrast, solubilities are affected by the water content of the subaluminous melt, where the solubilities of all the accessory phases examined increase with the water content of the melt, up to 2 wt.% H₂O. At higher water contents, solubilities are nearly constant. It can be concluded that water is not an important control of accessory phase solubility, although the water content will affect diffusivities of components in the melt, thus whether or not accessory phases will be present as restite material. The solubility behaviour in the subaluminous and peralkaline melts supports previous spectroscopic studies, which have observed differences in the coordination of high field strength elements in dry vs. wet subaluminous granitic glasses, but not for peralkaline granitic glasses. Lastly, the fact that wolframite solubility increases with increasing water content in the subaluminous melt suggests that tungsten dissolved as a hexavalent species.     

Quaternary stresses revealed by calcite twinning inversion: insights from observations in the Savonnières underground quarry (eastern France)

Calcite samples were extracted both from the rock matrix and the superficial coating of a karstified fault plane of an underground quarry, located in the eastern border of the Paris basin. The karstification is dated as Quaternary. Analysis of mechanical calcite twinning reveals that only the calcite matrix has also undergone a compression trending WNW that can be attributed to the Mio-Pliocene alpine collision. Both coating and matrix have undergone a strike-slip regime with σ₁ roughly trending north–south, that could correspond to the regional present-day state of stress, a strike-slip compression rather trending NNW, modified by local phenomena. To cite this article: M. Rocher et al., C. R. Geoscience 335 (2003).     

HYDROGEOLOGY

正20141756 Chen Ruige(Mathematical College,China University of Geosciences,Beijing100083,China);Zhou Xun Numerical Simulation of Groundwater Level Fluctuation in a Coastal Confined Aquifer with Sloping Initial Groundwater Level Induced by the Tide(Geological Bulletin of China,ISSN1671-2552,CN11-4648/P,32(7),2013,p.1099-1104,6 illus.,16 refs.) Key words:confined water,groundwater level     

METAMORPHIC PETROLOGY

正20141408 Cai Jia(Institute of Geology,Chinese Academy of Geological Sciences,Beijing100037,China);Liu Fulai Petrogenesis and Metamorphic P-T Conditions of Garnet-Spinel-Biotitebearing Paragneiss in Danangou Area,Daqingshan-Wulashan Metamorphic Complex Belt(Acta Petrologica Sinica,ISSN1000-0569,CN11-1922/P,29(7),     

SERIALS

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GEOPHYSICAL EXPLORATION

正20142386An Guoying(China Aero Geophysical Survey and Remote Sensing Center for Land and Resources,Beijing 100083,China)Application of Satellite Remote Sensing in Regional Hydrogeological Investigation:Taking Cenozoic Strata in Wenquan Sheet(1∶250 000)of Karakoram Range as an Example(Geosci-     

QUATERNARY GEOLOGY & GEOMORPHOLOGY

正20141016An Chengbang(Key Laboratory of Western China’s Environmental Systems,Ministry of Education,Lanzhou University,Lanzhou 730000,China);Zhao Yongtao Lake Records during the Last Glacial Maximum from Xinjiang,NW China and Their Climatic Impli-     

PETROLEUM GEOLOGY

正20141538 Cao Qing(School of Earth Sciences and Engineering,Xi’an Petroleum University,Xi’an 710065,China);Zhao Jingzhou Characteristics and Significance of Fluid Inclusions from Majiagou Formation,Yichuan Huangling Area,Ordos Basin(Advances in Earth Science,ISSN1001-8166,CN62-1091/P,28(7),2013,p.819-828,7 illus.,3 tables,43 refs.)     

GEOCHEMISTRY

正20142002 Wei Hualing(Institute of Geophysical and Geochemical Exploration,Chinese Academy of Geological Sciences,Langfang065000,China);Zhou Guohua Element Content and Mineral Compositions in Different Sizes of Soil in Tongling Area,Anhui Province(Geological Bulletin of China,ISSN1671-2552,CN11-4648/P,32(11),2013,p.1861