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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

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

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

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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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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

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

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

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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

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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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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

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

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

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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

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the Chinese Continental Drilling Program: Isotopic （O, Sr, Nd, Pb） and Fluid Inclusion Investigations on a Vertical Sequence of Ultrahigh-pressure Metamorphism

The Chinese Continental Drilling Program: Isotopic （O, Sr, ...

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2004年全国岩石学与地球动力学研讨会

作者： Jochen Hoefs Rolf L. Romer Alfons van den Kerkhof geowissenschaftliches zentrum der universitt gttingen Goldschmidtstr. 1 D-37077 Gttingen Germany geoForschungszentrum Potsdam Telegrafenberg D-14473 Potsdam Germany geowissenschaftliches zentrum der universitt gttingen Goldschmidtstr. 1 D-37077 Gttingen Germany

＜正＞ Introduction Aiming to determine the nature and extent of fluid/rock interactions during UHP metamorphism, to reveal possible changes of fluid compositions in both vertical and horizontal sequences of subducted...

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

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矿物岩石地球化学通报 2007年第Z1期26卷 61-62页

作者： Yilin Xiao Weidong Sun Jochen Hoefs Klaus Simon Zeming Zhang Shuguang Li Albrecht W. Hofmann 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 Geldschmittstrasse 1 D- 37077 G(o)ttingen Germany Key Laboratory of Isotope geochronology and geochemistry Guangzhou Institut of Geochemistry Chinese Academy of Sciences Wushan Guangzhou 510640China Max-Planck Institute fuer Chemie Postfach 3060 D-55020 Mainz Germany geowissenschaftliches zentrum der universit(a)t g(o)ttingen Geldschmittstrasse 1 D- 37077 G(o)ttingen Germany Institute of geology Chinese Academy of Geological Sciences Beijing 100037 China CAS Key Laboratory of Crust-Mantle and Environments School of Earth and Space Sciences University of Science and Technology of China Hefei 230026 China Max-Planck Institute fuer Chemie Postfach 3060 D-55020 Mainz Germany

　　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

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Petrogenesis and tectonic implications of Late Carboniferous A-type granites and gabbronorites in NW Iran:geochronological and geochemical constraints

Petrogenesis and tectonic implications of Late Carboniferous...

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中国科学院地质与地球物理研究所2015年度（第15届）学术年会

作者： Hadi Shafaii Moghadam Xian-Hua Li Xiao-Xiao Ling Robert J.Stern Jose F.Santos guido Meinhold ghasem ghorbani Shirin Shahabi State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of Sciences School of Earth Sciences Damghan University geosciences Dept. University of TX at Dallas geobiotec Departamento de GeociênciasUniversidade de Aveiro geowissenschaftliches zentrum der universit?t g?ttingen

Carboniferous igneous rocks constitute volumetrically minor components of Iranian crust but preserve important information about the magmatic and tectonic history of SW *** granites and gabbronorites in NW Iran comprise a bimodal magmatic suite that intruded Ediacaran–Cambrian gneiss and are good representatives of carboniferous igneous *** SIMS U–Pb zircon ages indicate that the gabbronorites and granites were emplaced synchronously at20 *** granites show A-type magmatic affinities,with typical enrichments in alkalis,ga,Zr,Nb and Y,depletion in Sr and P and fractionated REE patterns showing strong negative Eu *** gabbronorites are enriched in LREEs,Nb,ta and other incompatible trace elements,and are similar in geochemistry to OIB-type *** and gabbronorites have similarεNd(t)(+1.3 to+3.4 and-0.1 to+4.4,respectively)and zirconεHf(t)(+1.7 to+6.2 and+0.94 to+6.5,respectively).the similar variation in bulk rockεNd(t)and zirconεHf(t)values and radiometric ages for the granites and gabbronorites indicate a genetic relationship between mafic and felsic magmas,either a crystal fractionation or silicate liquid immiscibility process;further work is needed to resolve petrogenetic *** compositional characteristics of the bimodal ghushchi complex are most consistent with magmatic activity in an extensional tectonic *** extension may have occurred during rifting of Cadomian fragments away from northern gondwana during early phases of Neotethys opening.

关键词： A-type granite gabbronorite Carboniferous Zircon U–Pb ages Iran

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