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激光剥蚀-电感耦合等离子体质谱:双外标结合基体归一定量校准策略

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分析化学 2017年第7期45卷 965-972页

作者：吴石头王亚平许春雪 geowissenschaftliches zentrum gttingen universitt

定量校准策略是激光剥蚀电感耦合等离子体质谱(AICP-MS)分析技术的重要组成部分,直接影响分析数据的质量。本研究评估了现有玻璃标准物质定值不确定度的相对大小,并探究了NISt、MPI-DINg和USgS系列玻璃标准物质之间的基体效应。结果表明... 详细信息

定量校准策略是激光剥蚀电感耦合等离子体质谱(AICP-MS)分析技术的重要组成部分,直接影响分析数据的质量。本研究评估了现有玻璃标准物质定值不确定度的相对大小,并探究了NISt、MPI-DINg和USgS系列玻璃标准物质之间的基体效应。结果表明,NISt610的定值不确定度优于其它玻璃标准物质,在本实验条件下,NISt、MPI-DINg和USgS系列玻璃标准物质之间的基体效应可忽略不计。在此基础上提出了双外标结合基体归一定量校准策略,外标分别为NISt610和St Hs6/80-g。此策略克服了由于NISt610主量成分与地质样品差别大而造成的主量元素准确度差以及St Hs6/80-g中某些微量元素含量低、定值不确定度较大等缺点。对比采用3种定量校准策略(单外标NSIt610基体归一法、单外标St Hs6/80g基体归一法和双外标基体归一法)校准的ML3B-g数据可知,双外标基体归一法有效避免了单外标基体归一法的不足,并提高了分析数据的准确度。采用双外标结合基体归一定量校准策略校准了BCR-2g、CgSg-2和KL-2g中的主量元素和微量元素。结果表明,绝大多数分析数据在定值不确定度范围内,验证了此校准策略的实用性。同时,本研究得到的主量微量元素数据进一步补充了BCR-2g、CgSg-2和KL-2g的定值数据库。

关键词：激光剥蚀-电感耦合等离子体质谱定量标准策略定值不确定度基体效应微区分析

Niobium-tantalum Fractionation During Slab Subduction: Implications for the Formation of Continental Crust

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Niobium-tantalum Fractionation During Slab Subduction: Impli...

中国矿物岩石地球化学学会第11届学术年会

作者： Jochen Hoefs Klaus Simon Albrecht W．Hofmann geowissenschaftliches zentrum der universitt gttingen Goldschmittstrasse 1D-37077 GttingenGermany geowissenschaftliches zentrum der universitt gttingen Goldschmittstrasse 1D-37077 GttingenGermany Max-Planck Institute fuer Chemie Postfach 3060D-55020 MainzGermany

＜正＞Compared with the oceanic crust, knowledge about the formation of the continental crust （CC） is relatively poor. Although melting of subducted slabs in the early history of the Earth has been considered as the major way that shaped the chemical characteristics of the CC by most geologists, as the CC shares many characteristics with modern adakites, some geologists argued that Archean ttg was formed in the same way as modern arcs rather than slab melting, whereas others proposed that melting at the bottom of the thickened oceanic crust was more important. Recently, the debate is mainly focused on the unique subchondritic Nb/ta value of the CC, and particularly, how Nb and ta fractionated from each other and consequently how, in detail, the CC was built.

关键词： niobium-tantalum fractionation slab subduction formation of continental crust

A NEW tYPE OF PRECAMBRIAN MEgASCOPIC FOSSILS:tHE JINXIAN BIOtA FROM NORtHEAStERN CHINA

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A NEW TYPE OF PRECAMBRIAN MEGASCOPIC FOSSILS:THE JINXIAN BIO...

第二届国际古生物学大会

作者： Joachim REItNER Abteilung geobiologie Geowissenschaftliches Zentrum der Universitt Gttingen Goldschmidtstr.3D-37077 Gttingen Germany

Precambrian fossils are crucial for our understanding the evolution of early organisms. Megascopic body fossils are more important because they potentially represent macroorganisms. However, the Precambrian fossil record is sparse and dominated by microfossils and microbial structures. Here we show a new type of megascopic fossils recovered from the Xingmincun Formation (probably Neoproterozoic age), northeastern China. the specimens are flat, flexible (easily corrugated) and discoidal in outline. Concentric or spiral ridges are preserved on both sides. Petrographical thin sec-

关键词： Megascopic fossils Precambrian Ediacaran Xingmincun Formation northeastern China Liaoning

Niobium-tantalum fractionation during slab subduction: Implications for the formation of continental crust

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Niobium-tantalum fractionation during slab subduction: Impli...

2006年全国岩石学与地球动力学研讨会

作者： Jochen Hoefs Klaus Simon Albrecht W.Hofmann geowissenschaftliches zentrum der universitt gttingen goldschmittstrasse 1 D-37077 GttingenGermany geowissenschaftliches zentrum der universitt gttingen goldschmittstrasse 1 D-37077 GttingenGermany Max-Planck Institut fuer Chemie Postfach 3060 D-55020 MainzGermany

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the significance of cherts as markers of Ocean Plate Stratigraphy and paleoenvironmental conditions:New insights from the Neoproterozoic-Cambrian Blovice accretionary wedge,Bohemian Massif

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geoscience Frontiers 2023年第1期14卷 162-180页

作者： LukášAckerman Jirízák Václav Kachlík Jan Pašava KarelZák Andreas Pack František Veselovsky Ladislav Strnad Institute of geology of the Czech Academy of Sciences Rozvojová269CZ-16500 Prague 6Czech Republic Czech geological Survey Klárov3CZ-11821 Prague 1Czech Republic Institute of geology and Paleontology Faculty of ScienceCharles UniversityAlbertov 6Prague 12843Czech Republic geowissenschaftliches zentrum Universität GöttingenGoldschmidtstraβe 1D-37077 GöttingenGermany Laboratories of the geological Institutes Faculty of ScienceCharles UniversityAlbertov 6Prague 12843Czech Republic

the Ediacaran to early Cambrian Blovice accretionary complex,Bohemian Massif,hosts abundant chert bodies that formed on an oceanic plate and were involved in subduction beneath the northern margin of *** relationships of cherts to their host,their microstructure and elemental as well as isotopic compositions revealed diverse processes of chert petrogenesis reflecting depositional environment and position on the oceanic *** deep-water cherts formed through a hydrothermal precipitation of silica-rich gels on outer trench swell of the subducted slab with none or only minor addition of terrigenous *** the contrary,the shallow-water cherts formed in lagoons on seamount slopes,and at least some of them represent a product of hydrothermal replacement of former carbonate and/or evaporite *** both chert types,the hydrothermal fluids were of low temperature and continuous pervasive hydrothermal alteration of oceanic crust,together with an elevated Si content in Neoproterozoic seawater,served as the major source of *** the other hand,minor carbon enrichment in chert is mostly linked to variable incorporation of organic matter that was deposited on the *** earth element(REE)systematics of the cherts indicate predominantly oxygenated environment for the shallow-water cherts whereas the deep-water cherts were deposited in diverse redox conditions,depending on their distance from hydrothermal *** these data,we demonstrate that the cherts once formed a part of Ocean Plate Stratigraphy(OPS)now dismembered and mixed with terrigenous siliciclastic material to form OPS mé*** our data with those from the existing literature,we show that cherts can serve as significant markers of OPS since the Archean,recording a complex interplay between seafloor-related volcanic(production of MORB-and OIB-like magmas)and sedimentary processes,hydrothermal activity at mid-ocean ridges and seamount chains as well as at outer slopes o

关键词： Chert Accretionary wedge Ediacaran triple oxygen isotopes Strontium isotopes Ocean Plate Stratigraphy

Deciphering fluid inclusions in high-grade rocks

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geoscience Frontiers 2014年第5期5卷 683-695页

作者： Alfons van den Kerkhof Andreas Kronz Klaus Simon geowissenschaftliches zentrum der universitat gottingen Goldschmidtstr.1-3 D 37073 GottingenGermany

the study of fluid inclusions in high-grade rocks is especially challenging as the host minerals have been normally subjected to deformation, recrystallization and fluid-rock interaction so that primary in- clusions, formed at the peak of metamorphism are rare. the larger part of the fluid inclusions found in metamorphic minerals is typically modified during uplift. these late processes may strongly disguise the characteristics of the ＂original＂ peak metamorphic fluid. A detailed microstructural analysis of the host minerals, notably quartz, is therefore indispensable for a proper interpretation of fluid inclusions. Cathodoluminescence （CL） techniques combined with trace element analysis of quartz （EPMA, LA- [CPMS） have shown to be very helpful in deciphering the rock-fluid evolution. Whereas high-grade metamorphic quartz may have relatively high contents of trace elements like ti and A1, low- temperature re-equilibrated quartz typically shows reduced trace element concentrations. the result- ing microstructures in CL can be basically distinguished in diffusion patterns （along microfractures and grain boundaries）, and secondary quartz formed by dissolution-reprecipitation. Most of these textures are formed during retrograde fluid-controlled processes between ca. 220 and 500 ℃, i.e. the range of semi-brittle deformation （greenschist-facies） and can be correlated with the fluid inclusions. In this way modified and re-trapped fluids can be identified, even when there are no optical features observed under the microscope.

关键词： Fluid inclusionsgranuliteCharnockiteCathodoluminescenceLA-ICPMSQuartz

Li and B Isotope Systematics of Ultrahigh-pressure Metamorphic Rocks from the Chinese Continental Scientific Drilling Program

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矿物岩石地球化学通报 2007年第Z1期26卷 81-82页

作者： Yilin Xiao Rolf L. Romer Jochen Hoefs Anette Meixner Zeming Zhang CAS Key Laboratory of Crust-Mantle and Environments School of Earth and Space Sciences University of Science and Technology of China Hefei 230026 China geowissenschaftliches zentrum der universit(a)t g(o)ttingen Goldschmidtstrasse 1 D-37077 G(o)ttingen Germany geo Forschungs zentrum Potsdam Telegrafenberg 14473 Potsdam Germany geowissenschaftliches zentrum der universit(a)t g(o)ttingen Goldschmidtstrasse 1 D-37077 G(o)ttingen Germany Institute of geology Chinese Academy of Geological Sciences Beijing 100037 China

　　1 Introduction　　Recent improvements in the precision of Li and B isotope measurements have demonstrated the potential of these elements in tracing a wide range of geological processes. the Li and B isotope systematics of ultrahigh-pressure (UHP) metamorphic rocks provides a unique opportunity to investigate the behaviour of Li and B during fluid-rock interaction at high temperatures and very high pressures and to constrain the fluid budget and the recycling of subducted crustal materials into the mantle during UHP metamorphism.　　……

关键词： isotope systematics ultrahigh-pressure metamorphic CCSD

garnets in leucogranites from the southern margin of North China Craton:Element and Oxygen isotope date

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Garnets in leucogranites from the southern margin of North C...

中国矿物岩石地球化学学会第13届学术年会

作者： gerhard Wrner Andreas Kronz Klaus Simon geowissenschaftliches zentrum gttingen Abt.GeochemieGoldschmidtstr.137077 GttingenGermany

＜正＞the late Jurassic Jingshan leucogranite is located in the south-eastern margin of the North China Craton and contains abundant *** this study,four types of garnets are found according to their occurrences in the Jingshan leucogranite:（a） garnets in biotite -rich restite（grtⅠ）;（b） xenocrystic garnets in leucogranite associated petrographically with abundant mafic minerals（grtⅡ）;（c） clustered garnet- xenocrysts with complex zoning in leucogranite（grtⅢ）;（d） small（＜100μm） euhedral phenocrystic garnets in aplite and granite（grtⅣ）.grtⅠusually shows euhedral morphology,whereas grtⅡor grtⅢoften occur together with grtⅣin intergrowths.

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Li and B Isotope Systematics of Ultrahigh-pressure Metamorphic Rocks from the Chinese Continental Scientific Drilling Program

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Li and B Isotope Systematics of Ultrahigh-pressure Metamorph...

中国矿物岩石地球化学学会第11届学术年会

作者： RolfL. Romer Jochen Hoefs Anette Meixner geo Forschungs zentrum Potsdam Telegrafenberg14473 PotsdamGermany geowissenschaftliches zentrum der universitit gttingen Goldschmidtstrasse 1D-37077 GttingenGermany geo Forschungs zentrum Potsdam Telegrafenberg14473 PotsdamGermany

＜正＞1 Introduction Recent improvements in the precision of Li and B isotope measurements have demonstrated the potential of these elements in tracing a wide range of geological processes. the Li and B isotope systematics of ultrahigh-pressure （UHP） metamorphic rocks provides a unique opportunity to investigate the behaviour of Li and B during fluid-rock interaction at high temperatures and very high pressures and to constrain the fluid budget and the recycling of subducted crustal materials into the mantle during UHP metamorphism.

关键词： isotope systematics ultrahigh-pressure metamorphic CCSD