玄武岩钛同位素分析标准物质研制

同位素标准物质是进行同位素准确分析的基础和关键,其同位素组成是同位素测量的基本参数。本文报道了玄武岩钛同位素标准物质的研制过程和定值结果,包括标准物质的选择、均匀性和稳定性检验、定值分析及测定数据的统计性检验等。玄武岩钛同位素标准物质的主要特性量值的推荐值及95%置信水平的不确定度为:δ~(47)Ti(‰)=-0.53±0.07,δ~(48)Ti(‰)=-1.05±0.09,δ~(49)Ti(‰)=-1.57±0.16,δ~(50)Ti(‰)=-2.10±0.18。该标准物质可用于地质样品钛同位素测定中化学流程评价和验证、质谱仪的校正及整个过程的分析质量控制。     

用于多接收器等离子体质谱测定的铁铜锌同位素标准溶液研制

近十来年铁铜锌同位素研究已经成为热门研究领域,铁铜锌同位素分析方法日趋成熟,但是铁铜锌同位素标准物质却十分匮乏。目前欧盟参考物质及测量研究所(IRMM)有1个铁同位素标准物质和1个锌同位素标准物质,前者售罄,后者价格昂贵;美国国家标准局(NIST)有1个铜同位素标准物质。为了适应我国铁铜锌同位素研究的发展,本文使用铁铜锌元素浓度标准溶液作为备选标准溶液研制了铁铜锌三个同位素标准溶液(CAGS-Fe、CAGS-Cu和CAGS-Zn)。三个备选标准溶液经过F检验均匀性良好;在38个月内δ56Fe、δ57Fe、δ65Cu、δ66Zn和δ68Zn值没有显著性变化,具有良好的稳定性;主要特性值的推荐值及95%置信水平的不确定度为:CAGS-Fe,δ56FeIRMM014(‰)=0.80±0.05,δ57FeIRMM014(‰)=1.20±0.10;CAGS-Cu,δ65CuIRMM976(‰)=0.57±0.06;CAGS-Zn,δ66ZnIRMM3702(‰)=-0.77±0.10,δ68ZnIRMM3702(‰)=-1.55±0.13。本文研制的标准溶液可用于多接收器等离子体质谱仪测定铁铜锌同位素时的仪器校正和质谱分析过程监控,对于不同实验室的测试数据对比具有重要意义。     

地质样品铜、铁、锌同位素标准物质的研制

合适的标准物质是进行同位素准确分析的基础和关键,本文介绍了基于地质样品的铜、铁、锌同位素分析标准参考物质的研制过程.所研制的标准物质为CAGSR-1,用于该标准物质研制的原始样品为玄武质组分的岩石成分分析国家标准物质GBW07105.按照国家一级标准的要求,对该标准物质进行了严格的均一性、稳定性检验和同位素定值分析.标准物质CAGSR-1的主要特性量值δ65Cu、δ56Fe、δ66Zn的推荐值及95%置信水平的不确定度为:δ65CuSRM976(‰)=0.10±0.02、δ56FeIRMM014(‰)=0.12±0.02、δ66ZnRomil(‰)=7.45±0.01.该标准物质可用于地质与环境样品铜、铁、锌同位素测定中化学流程评价和验证、质谱仪的校正及整个过程的分析质量控制.     

有机化学物质碳氮稳定同位素系列标准物质研制

实验室和研究人员所使用的碳、氮同位素标准物质一般由国际原子能机构(IAEA)获得,然而近年来,随着碳氮同位素在实验室质量监控、方法评价、仪器校准等方面的广泛应用,市场需求量不断增加, IAEA研制的碳、氮同位素标准物质的种类与数量逐渐不能满足科学研究快速发展的需求。我国急需研制适应当今分析技术水平的有机质碳氮同位素国家标准物质用以进行质量监控、方法评价、仪器校准。为保证量值传递精度,本文研制了4个有机化学物质的碳氮稳定同位素标准物质,其中3个为尿素样品,1个为L-谷氨酸。经检验4种标准物质的均匀性通过F值检验,标准物质的δ~(13)C和δ~(15)N值经过一年的稳定性检验,特征量值变化在测量方法允许的不确定度范围内,由此判定δ~(13)C和δ~(15)N值稳定性良好。由包括研制单位实验室在内的12家实验室协同定值,采用高温燃烧-气体同位素质谱法测定了δ~(13)C和δ~(15)N值,系列标准物质δ~(13)C和δ~(15)N认定值区间呈梯度分布,δ~(13)C值为-40‰～0‰,δ~(15)N值为-10‰～30‰,涵盖了我国天然样品中有机质碳氮稳定同位素组成范围;研制的系列标准物质δ~(13)C的定值扩展不确定度不大于0.08‰,δ~(15)N的定值扩展不确定度不大于0.09‰,定值水平与国际标准物质相当。该系列标准物质已被国家质检总局批准为国家一级标准物质,批准号为GBW04494～GBW04497。可被用于地质、生态、环境等多种样品δ~(13)C和δ~(15)N比值测定时的分析监控、仪器校准、方法评价、质量保证和质量监控。     

黑色页岩铁同位素标准物质的研制

本文选择宜昌三峡地区九龙湾剖面采集的黑色页岩作为黑色页岩Fe同位素备选标准物质, 命名为CAGS-BS。使用单因素方差分析法对CAGS-BS进行均匀性检验; 使用t检验对其在24个月中四次分析的数据进行长期稳定性的检验, 结果显示均匀性和稳定性良好, 满足标准物质的要求。黑色页岩Fe同位素标准物质采用多家实验室协作定值的方法确定特征量值。协作定值的单位包括: 中国地质科学院地质研究所, 中国科学技术大学, 中国地质大学(北京), 天津大学和中国科学院广州地球化学研究所。剔除了可疑值之后的数据符合正态分布, 可以采用算术平均法进行标准物质的定值。标准物质不确定度由协作测定的不确定度分量(uchar)、批内瓶间差异引起的不均匀性不确定度分量(ubb’)和实验室保存引起的长期不稳定性不确定度分量(ults)共同确定, 总不确定度为扩展不确定度, 包含因子(k)等于2。得到CAGS-BS的特征值及不确定度为: δ56FeIRMM-014/‰ = 0.10 ± 0.04。该标准物质可用于黑色页岩样品的化学流程评价和验证、质谱仪的校正及整个过程的分析质量控制。     

水中系列氢氧同位素标准物质的研制

我国氢氧同位素国家一级标准物质经过二十余年的使用,现已不能满足需求,急需研制代表当今分析技术水平的新的氢氧同位素国家标准物质。本文研制了系列(4个)水中氢氧同位素标准物质,其中三个采自天然水样,一个为人工配制的贫氘水,三种天然水样基本涵盖了我国境内天然水的氢氧同位素组成范围。每种标准物质随机抽取30瓶的均匀性子样,每份子样做双份分析,进行均匀性检验,四种标准物质的均匀性检验得到的F值都小于相应的自由度的临界值,显示四种标准物质的均匀性良好。标准物质的δ¹⁸O和δD值经过2年的稳定性检验,特征量值变化在不确定度范围,由此判定δD、δ¹⁸O值稳定性良好。采用国际间实验室采用不同原理的方法协同定值,11家国内外实验室分别采用Cr还原法、激光法、H₂-H₂O平衡法、高温热转换元素分析法进行水中氢同位素定值,采用CO₂-H₂O平衡法进行氧同位素定值;定值不确定度显著降低,δ¹⁸O的扩展不确定度小于0.08‰,δD的扩展不确定度小于0.9‰。该标准物质已被国家质检总局批准确为国家一级标准物质,批准号为GBW 04458~GBW 04461。     

磁铁矿铁同位素标准物质的研制

中国地质科学院地质研究所研制了磁铁矿铁同位素标准物质,将其命名为CAGS-MAG.研制过程中使用单因素方差分析法对CAGS-MAG进行均匀性检验,使用趋势检验对其在30个月中5次分析数据进行长期稳定性检验,结果显示均匀性和稳定性良好,满足标准物质的要求.CAGS-MAG的特征值采用多家实验室协作定值的方法确定.协作定值...     

MC-ICP-MS高精度Cu、Zn同位素测试技术

过渡族元素同位素是国际上同位素地球化学研究的热点。测试技术的限制是制约过渡元素同位素研究发展的关键。笔者利用Neptune型多接收等离子质谱(MC-ICP-MS),采用Cu、Zn互为内标的方法对仪器的质量歧视进行了校正,对基质效应和测试方法的重现性进行了检验,建立了高精度的Cu、Zn同位素测试技术。在5个月内对实验室标准IMRCu和IMRZn进行了测量,结果分别为δ65CuNIST976=(0.34±0.08)‰(2SD,n=32),δ66ZnJMCZn=(-9.64±0.05)‰(2SD,n=26),δ67ZnJMCZn=(-14.37±0.16)‰(2SD,n=26),δ68ZnJMCZn=(-19.01±0.08)‰(2SD,n=26),分析精度达到国际同类实验室先进水平。对Cu、Zn同位素参考物质进行了对比测量,分析结果与报道值在误差范围内完全一致。     

钕同位素比值~(143)Nd/~(144)Nd标准溶液研制

钕同位素比值(~(143)Nd/~(144)Nd)是Sm-Nd同位素方法的关键量值,由于被测样品的~(143)Nd/~(144)Nd比值变化范围很小,所以对~(143)Nd/~(144)Nd比值测试的精准度要求很高(精度优于0.005%)。为了获得高精度和高准确度的测试数据,分析过程中所用Nd同位素标准物质起着重要作用。以往的Nd同位素标准物质都是氧化钕,经过近三十年有的已消耗殆尽。本文阐述了钕同位素比值~(143)Nd/~(144)Nd标准溶液的研制,经检验标准溶液的均匀性和稳定性良好,由11家实验室协同定值,采用MC-TIMS和MC-ICP-MS方法测定~(143)Nd/~(144)Nd,确定了Nd同位素标准溶液的特性值~(143)Nd/~(144)Nd=0.512438,不确定度为5×10-6。此标准溶液于2015年5月获得国家标准样品证书(批号为GSB 04-3258—2015),可被用于地质、资源、海洋、环境、考古等多种样品~(143)Nd/~(144)Nd比值测定时的仪器校准和分析过程的质量监控。     

渤海东海海洋沉积物中碳氮稳定同位素标准物质研制

海洋沉积物中碳氮稳定同位素因其能够确定有机质的来源,有助于了解碳循环、气候变化、有机质迁移转化而备受关注,但其分析测试过程中尚缺乏海洋沉积物碳氮稳定同位素标准物质进行质量监控。本文依据ISO导则35和国家《一级标准物质技术规范》(JJG1006—1994),研制了三个海洋沉积物碳氮稳定同位素标准物质(MSCNI-1、MSCNI-2和MSCNI-3),候选物样品分别采自我国渤海锦州湾湿地、东海闽浙近岸和东海冲绳海槽,定值组分为总碳氮同位素(δ~(13)C-TC、δ~(15)N-TN)和有机碳氮同位素(δ~(13)C-C~(org)、δ~(15)N-N~(org)),定值方法采用元素分析-同位素比值质谱法(EA-IRMS)多家实验室协同定值。经检验,三个标准物质候选物均匀性良好,一年内定值组分均无显著变化,具有良好的稳定性;δ~(13)C和δ~(15)N的标准不确定度分别小于0.15%和0.24%,标准值和标准不确定度合理。该套标准物质是我国以海底沉积物为介质的基体型碳氮稳定同位素标准物质,定值方法准确可靠,可供海洋、地质及环境等相关领域实验室用于仪器校准、方法评价和质量监控等。     

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

正~~     

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