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1.
激光探针分析在氧同位素地球化学研究中的应用 总被引：6，自引：0，他引：6
简要介绍了氧同位素分析的最新方法———激光探针法的主要特点,并详细评述了激光探针分析在氧同位素地球化学研究中的应用。某些矿物内部存在氧同位素组成的变化,构成氧同位素环带。与其他化学成分环带一样,矿物氧同位素环带也可以分为生长环带（包括次生加大的环带）和扩散环带两种。变质岩中石榴石经常保存有明显的生长环带,而矽卡岩中石榴石、变质花岗质岩石中锆石和蚀变花岗岩中石英等矿物均可以记录岩石形成早期的某些氧同位素特征。由于这种差异与岩石的形成环境有关,因此通过对矿物氧同位素组成的微区分析可揭示岩石的某些成因信息。在缓慢冷却的变质岩中,磁铁矿的氧同位素环带常是扩散作用形成的,由此可以确定岩石的冷却速率。通过对脉石英的激光探针分析,可以研究流体的流动机理。变质岩的氧同位素微区分析为ｐ Ｔ ｔ ｆ轨迹研究提供了有力的武器,而氧同位素示踪可用来解决流体在变质岩形成过程中的作用问题。 相似文献
2.
简要地比较了ＣｌＦ３和ＢｒＦ５两种常规氟化法的优缺点。在此基础上介绍了激光氟化法（又称激光探针法）的主要构成和特点以及激光探针法的分析精度和分析不同矿物时的特点。激光探针法具有样品处理简单、用量少、速度快和可作原位分析等优点。激光探针法的使用为地幔氧同位素系统的研究勾画了一幅新的图景；在微区同位素分析、交换反应动力学等方面也展示了良好的应用前景 相似文献
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激光剥蚀等离子质谱微区分析在固体地球科学中的应用进展 总被引：5，自引：1，他引：5
当前分析化学技术正向着痕量微区方向发展。这使得我们能够用更小更少的样品直接得到更多的地球化学信息。在诸多微区测试技术中,激光剥蚀等离子质谱（LA-ICPMS）技术发展最快。其地质应用较广,激光探针等离子体质谱能够进行固体样品的微区微量元素和同位素的分析,具有灵敏度高、简便、快速的特点,同样具有在同位素定年上的潜力。近年来又研制出激光剥蚀多道接收等离子质谱（LA-MC-ICPMS）仪,使得微区同位素分析开始了新的革命。而多种微区技术综合应用为近几年分析地球化学新的趋势。 相似文献
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氧同位素在岩石成因研究的新进展 总被引：1，自引：1，他引：0
通过氧同位素分析可以对岩石的成因进行认识,使之成为岩石学研究的一个强有力工具。根据花岗岩的氧同位素高低可以判断其来源于变沉积岩还是变火成岩;对于一个复式岩体,如果不同期次岩石的氧同位素组成存在明显变化,可以有效地判断该岩浆在演化过程中存在不同来源物质的混染,因为岩浆从镁铁质成分向长英质成分的化学分异过程,不会引起明显的氧同位素分馏,分馏值一般不超过0.3‰。氧同位素分析手段从常规BrF5法,到激光探针BrF5法,再到离子探针分析法,对岩石矿物样品从全熔分析到微区分析的发展,显示了它们的发展历程和各自的优势及应用范围。本文介绍了氧同位素的不同分析方法,以花岗岩(流纹岩)和变质岩的研究为例阐述了氧同位素分析技术的发展。苏州花岗岩利用全岩和造岩矿物常规氧同位素分析方法得出其为低δ18O和正常δ18O岩浆成因的不同认识,近年通过锆石激光氧同位素分析技术,获得岩浆锆石的δ18O平均为4.92‰,证实其来源于壳源的低δ18O岩浆。类似地,利用全岩和造岩矿物常规氧同位素分析方法得出的观点难以解释美国黄石高原低δ18O流纹岩中矿物颗粒间和颗粒内部的氧同位素变化,该氧同位素变化只能通过离子探针矿物微区原位分析得出。在变质岩研究方面,通过激光探针氧同位素分析,人们普遍认为苏鲁造山带变质岩极负的δ18O值是在新元古代原岩形成时获得的,但是最新的离子探针锆石原位氧同位素分析表明苏鲁造山带变质岩极负的δ18O主要是在三叠纪超高压变质作用过程中获得的。今后单颗粒矿物尺度上的氧同位素组成分布规律将是氧同位素研究的发展方向。 相似文献
6.
铁同位素分析测试技术研究进展 总被引：5，自引：3，他引：2
铁是地球上丰度最高的变价元素,在自然界大量分布于各类矿物、岩石、流体和生物体中,并广泛参与成岩作用、成矿作用、热液活动和生命活动过程。铁同位素组成对地球化学、天体化学和生物化学方面提供重要的信息,是同位素地球化学研究领域的热点。铁同位素的精确测量是开展相关研究的重要基础。本文评述了铁同位素测试技术的研究进展,主要包括:①溶液法测试铁同位素样品纯化过程中阴离子树脂的改进;②质谱分析从传统的热电离质谱法发展为多接收电感耦合等离子体质谱法;③激光微区原位测试技术的研发等。在此基础上,对测试过程中会导致产生铁同位素分馏的步骤和校正方法进行了总结,并对各种测试方法的优缺点进行了评述。本文认为:溶液法分析流程长且复杂,但分析精度高(0.03‰,2SD)、方法稳定;微区原位分析方法从纳秒激光剥蚀发展为飞秒激光剥蚀,脉冲持续时间更短、脉冲峰值强度更高(可达10~(12)W),聚焦强度超过10~(20)W/cm~2,使其具有分析速度快、空间分辨率高的优势。微区原位法可以从微观角度去讨论铁同位素变化的地球化学过程,但基体效应的存在限制了微区原位铁同位素的广泛应用。因此,缩短溶液法分析流程,开发系列基体匹配的标准样品,是铁同位素分析方法研发的方向。 相似文献
7.
激光熔蚀微量氧同位素分析方法及其地质应用 总被引：2，自引：1，他引：1
研究小尺度或微区的同位素组成变化已成为地球化学分析技术发展的重要方向之一。在研制CO2激光熔蚀氧同位素制样装置的基础上,通过该装置与MAT253质谱计联机实现了硅酸盐和氧化物矿物的氧同位素在线分析。所测样品包括NBS28石英标样、石英玻璃,以及天然的石榴子石、锆石、橄榄石等一些难熔矿物。该装置分析的颗粒样品氧同位素分析精度为±022‰,最低样品量为8μmol的O2;石英玻璃原位分析的氧同位素分析精度为±035‰,最低样品量为7μmol的O2。这种装置和分析方法具备速度快,熔样温度高的特点,尤其适于难熔矿物。该装置可采用脉冲激光实现石英玻璃的微区原位分析,可应用于单个矿物生成环带的氧同位素研究。 相似文献
8.
锆石地球化学特征及地质应用研究综述 总被引：11，自引：0，他引：11
介绍并对比了用于锆石等副矿物测试的离子探针、激光探针、电子探针、质子探针等几种微区原位测试技术各自的特点.锆石U-Pb定年实现了对同一锆石颗粒内部不同成因的锆石域进行原位年龄的分析,给出了有关寄主岩石的源岩、地质演化历史等重要信息,为地质过程的精细年龄框架的建立提供了有效的途径.锆石微量元素、同位素特征是译解岩石来源和成因的指示器.锆石Hf同位素已成功地用于地球早期历史、岩浆来源、壳幔相互作用、区域大陆地壳增长的研究等;锆石氧同位素组成能有效地约束壳幔相互作用和示踪岩浆来源等. 相似文献
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激光探针：稳定同位素分析的新式“武器”＊Ｉ：发展历史、工作原理和装置构成肖益林郑永飞（中国科学技术大学地球与空间科学系，合肥２３００２６）关键词激光探针稳定同位素分析发展历史工作原理装置稳定同位素地球化学的发展与同位素分析方法的不断改进和完善密不可分... 相似文献
11.
综述了近年来流体包裹体原位测定的分析方法,其中较为常用的方法为激光拉曼光谱法,质子探针法等。激光烧蚀法是最近发展起来的一种打开单个包裹体的新方法。该方法与其它技术相结合对测定流体包裹有一定的发展前景。 相似文献
12.
Raphaelle Escoube Olivier J. Rouxel Béatrice Luais Emmanuel Ponzevera Olivier F.X. Donard 《Geostandards and Geoanalytical Research》2012,36(2):149-159
Recent analytical developments in germanium stable isotope determination by multicollector ICP‐MS have provided new perspectives for the use of Ge isotopes as geochemical tracers. Here, we report the germanium isotope composition of the NIST SRM 3120a elemental reference solution that has been calibrated relative to internal isotopic standard solutions used in the previous studies. We also intercalibrate several geological reference materials as well as geological and meteoritic samples using different techniques, including online hydride generation and a spray chamber for sample introduction to MC‐ICP‐MS, and different approaches for mass bias corrections such as sample–calibrator bracketing, external mass bias correction using Ga isotopes and double‐spike normalisation. All methods yielded relatively similar precisions at around 0.1‰ (2s) for δ74/70Ge values. Using igneous and mantle‐derived rocks, the bulk silicate Earth (BSE) δ74/70Ge value was re‐evaluated to be 0.59 ± 0.18‰ (2s) relative to NIST SRM 3120a. Several sulfide samples were also analysed and yielded very negative values, down to ?4.3‰, consistent with recent theoretical study of Ge isotope fractionation. The strong heavy isotope depletion in ore deposits also contrasts with the generally positive Ge isotope values found in many modern and ancient marine sediments. 相似文献
13.
Daniel A. Frick Jan A. Schuessler Michael Sommer Friedhelm von Blanckenburg 《Geostandards and Geoanalytical Research》2019,43(1):77-91
Silicon is a beneficial element for many plants and is deposited in plant tissue as amorphous bio‐opal called phytoliths. The biochemical processes of silicon uptake and precipitation induce isotope fractionation: the mass‐dependent shift in the relative abundances of the stable isotopes of silicon. At the bulk scale, δ30Si ratios span from ?2 to +6‰. To further constrain these variations in situ, at the scale of individual phytolith fragments, we used femtosecond laser ablation multi‐collector inductively coupled plasma‐mass spectrometry (fsLA‐MC‐ICP‐MS). A variety of phytoliths from grasses, trees and ferns were prepared from plant tissue or extracted from soil. Good agreement between phytolith δ30Si ratios obtained by bulk solution MC‐ICP‐MS analysis and in situ isotope ratios from fsLA‐MC‐ICP‐MS validates the method. Bulk solution analyses result in at least twofold better precision for δ30Si (2s on reference materials ≤ 0.11‰) over that found for the means of in situ analyses (2s typically ≤ 0.24‰). We find that bushgrass, common reed and horsetail show large internal variations up to 2‰ in δ30Si, reflecting the various pathways of silicon from soil to deposition. Femtosecond laser ablation provides a means to identify the underlying processes involved in the formation of phytoliths using silicon isotope ratios. 相似文献
14.
高精度Lu—Hf同位素测定的新技术与新方法 总被引：3，自引：0，他引：3
综述了Ｌｕ－Ｈｆ同位素体系的基本地质地球化学特征,对比了Ｌｕ－Ｈｆ同位素现有的分析方法,并介绍了包括化学流程在内的应用多接收器双耦合等离子体质谱仪（ＭＣ－ＩＣＰ－ＭＳ）进行高精度和高准确度,Ｌｕ－Ｈｆ同位素分析的原理和测试过程,列举了部分最新地质应用成果。 相似文献
15.
Klaus Peter Jochum Steven A. Wilson Wafa Abouchami Marghaleray Amini Jérome Chmeleff Anton Eisenhauer Ernst Hegner Linda M. Iaccheri Bruno Kieffer Joachim Krause William F. McDonough Regina Mertz‐Kraus Ingrid Raczek Roberta L. Rudnick Denis Scholz Grit Steinhoefel Brigitte Stoll Andreas Stracke Sonia Tonarini Dominique Weis Ulrike Weis Jon D. Woodhead 《Geostandards and Geoanalytical Research》2011,35(2):193-226
This paper contains the results of an extensive isotopic study of United States Geological Survey GSD‐1G and MPI‐DING reference glasses. Thirteen different laboratories were involved using high‐precision bulk (TIMS, MC‐ICP‐MS) and microanalytical (LA‐MC‐ICP‐MS, LA‐ICP‐MS) techniques. Detailed studies were performed to demonstrate the large‐scale and small‐scale homogeneity of the reference glasses. Together with previously published isotopic data from ten other laboratories, preliminary reference and information values as well as their uncertainties at the 95% confidence level were determined for H, O, Li, B, Si, Ca, Sr, Nd, Hf, Pb, Th and U isotopes using the recommendations of the International Association of Geoanalysts for certification of reference materials. Our results indicate that GSD‐1G and the MPI‐DING glasses are suitable reference materials for microanalytical and bulk analytical purposes. 相似文献
16.
Chao Huang Hao Wang Jin‐Hui Yang Jahandar Ramezani Chuan Yang Shao‐Bing Zhang Yue‐Heng Yang Xiao‐Ping Xia Lian‐Jun Feng Jie Lin Tian‐Tian Wang Qian Ma Huai‐Yu He Lie‐Wen Xie Shi‐Tou Wu 《Geostandards and Geoanalytical Research》2020,44(1):103-123
A new natural zircon reference material SA01 is introduced for U‐Pb geochronology as well as O and Hf isotope geochemistry by microbeam techniques. The zircon megacryst is homogeneous with respect to U‐Pb, O and Hf isotopes based on a large number of measurements by laser ablation‐inductively coupled plasma‐mass spectrometry (LA‐ICP‐MS) and secondary ion mass spectrometry (SIMS). Chemical abrasion isotope dilution thermal ionisation mass spectrometry (CA‐ID‐TIMS) U‐Pb isotopic analyses produced a mean 206Pb/238U age of 535.08 ± 0.32 Ma (2s, n = 10). Results of SIMS and LA‐ICP‐MS analyses on individual shards are consistent with the TIMS ages within uncertainty. The δ18O value determined by laser fluorination is 6.16 ± 0.26‰ (2s, n = 14), and the mean 176Hf/177Hf ratio determined by solution MC‐ICP‐MS is 0.282293 ± 0.000007 (2s, n = 30), which are in good agreement with the statistical mean of microbeam analyses. The megacryst is characterised by significant localised variations in Th/U ratio (0.328–4.269) and Li isotopic ratio (?5.5 to +7.9‰); the latter makes it unsuitable as a lithium isotope reference material. 相似文献
17.
John B. Creech Bruce F. Schaefer Simon P. Turner 《Geostandards and Geoanalytical Research》2020,44(2):223-229
Recent developments in amplifier hardware enable low‐noise measurements of exceedingly small ion beams in isotope ratio analysis, yielding higher precision from smaller samples than ever before. To date, these amplifiers have largely been employed in thermal ionisation instruments, with few applications using plasma‐source (i.e., MC‐ICP‐MS) instruments. Here, we demonstrate the utility of these new generation 1013 Ω amplifiers in MC‐ICP‐MS, employing Pt isotopes as a case study, a system that could greatly benefit from the promised advances. The data demonstrate that for samples with low Pt abundance, for a modest increase in uncertainties, the amount of sample required can be reduced by a factor of 50–100. This technique thereby opens up new possibilities for analysis of samples that have low Pt mass fractions or were otherwise impossible to obtain in sufficient quantities. 相似文献
18.
Michael A.W. Marks Roberta L. Rudnick Thomas Ludwig Horst Marschall Thomas Zack Ralf Halama William F. McDonough Detlef Rost Thomas Wenzel Edward P. Vicenzi Ivan P. Savov Rainer Altherr Gregor Markl 《Geostandards and Geoanalytical Research》2008,32(3):295-310
Two large pegmatitic crystals of sodic pyroxene (aegirine) and sodic amphibole (arfvedsonite) from the agpaitic igneous Ilímaussaq Complex, south Greenland were found to be suitable as reference materials for in situ Li isotope determinations. Lithium concentrations determined by SIMS and micro‐drilled material analysed by MC‐ICP‐MS generally agreed within analytical uncertainty. The arfvedsonite crystal was homogeneous with [Li] = 639 ± 51 μg g?1 (2s, n = 69, MC‐ICP‐MS and SIMS results). The aegirine crystal shows strongly developed sector zoning, which is a common feature of aegirines. Using qualitative element mapping techniques (EPMA), the homogeneous core of the crystal was easily distinguished from the outermost sectors of the crystals. The core had a mean [Li] of 47.6 ± 3.6 μg g?1 (2s, n = 33) as determined by SIMS. The seven micro‐drilled regions measured by solution MC‐ICP‐MS returned slightly lower concentrations (41–46 μg g?1), but still overlap with the SIMS data within uncertainty. Based on MC‐ICP‐MS and SIMS analyses, the variation in δ7Li was about 1‰ in each of the two crystals, which is smaller than that in widely used glass reference materials, making these two samples suitable to serve as reference materials. There was, however, a significant offset between the results of MC‐ICP‐MS and SIMS. The latter deviated from the MC‐ICP‐MS results by ?6.0 ± 1.9‰ (2s) for the amphibole and by ?3.9 ± 1.9‰ (2s) for the aegirine. This indicates the presence of a significant matrix effect in SIMS determinations of Li isotopes for amphibole and pyroxene relative to the basalt glasses used for calibration. Based on the MC‐ICP‐MS results, mean δ7Li values of +0.7 ± 1.2‰ (2s, n = 10) for the arfvedsonite crystal and of ?3.7 ± 1.2‰ (2s, n = 7) for the core of the aegirine crystal were calculated. Adopting these values, SIMS users can correct for the specific IMF (instrumental mass fractionation) of the ion probe used. We propose that these two crystals serve as reference materials for in situ Li isotope determinations by SIMS and pieces of these two crystals are available from the first author upon request. 相似文献
19.
Kathryn L. Linge L. Paul Bédard Roxana Bugoi Jacinta Enzweiler Klaus Peter Jochum Rüdiger Kilian Jingao Liu Johanna Marin‐Carbonne Silke Merchel Frans Munnik Luiz F.G. Morales Claire Rollion‐Bard A. Kate Souders Paul J. Sylvester Ulrike Weis 《Geostandards and Geoanalytical Research》2017,41(4):493-562
This GGR biennial critical review covers developments and innovations in key analytical methods published since January 2014, relevant to the chemical, isotopic and crystallographic characterisation of geological and environmental materials. In nine selected analytical fields, publications considered to be of wide significance are summarised, background information is provided and their importance evaluated. In addition to instrumental technologies, this review also presents a summary of new developments in the preparation and characterisation of rock, microanalytical and isotopic reference materials, including a précis of recent changes and revisions to ISO guidelines for reference material characterisation and reporting. Selected reports are provided of isotope ratio determinations by both solution nebulisation MC‐ICP‐MS and laser ablation‐ICP‐MS, as well as of radioactive isotope geochronology by LA‐ICP‐MS. Most of the analytical techniques elaborated continue to provide new applications for geochemical analysis; however, it is noted that instrumental neutron activation analysis has become less popular in recent years, mostly due to the reduced availability of nuclear reactors to act as a neutron source. Many of the newer applications reported here provide analysis at increasingly finer resolution. Examples include atom probe tomography, a very sensitive method providing atomic scale information, nanoscale SIMS, for isotopic imaging of geological and biological samples, and micro‐XRF, which has a spatial resolution many orders of magnitude smaller than conventional XRF. 相似文献