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Acta Geologica Sinica(English Edition) 2016年第S1期90卷 84-85页

作者： Wilson TEIXEIRA Mike A.HAMILTON Vicente A.V.GIRARDI Frederico M.FALEIROS University of Sao Paulo Institute of Geosciences Jack Satterly geochronology laboratory Department of Earth SciencesUniversity of Toronto

High-resolution U–Pb(ID-TIMS,baddeleyite)ages are presented for mafic dykes from selected swarms in two important Amazonian regions:the Carajás Province in the east,and the Rio Apa block in the southwest–areas

关键词： Pb U-Pb Constraints on Supercontinent Cycles and Geodynamic Connections with Global LIP Events Through Time Key Dolerite Dyke Swarms of Amazonia LIP

Geochemistry and geodynamic significance of the rare-earth mineralized Paleoproterozoic Longwangzhuang granite on the southern margin of the North China Craton

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Chinese Journal Of Geochemistry 2011年第2期30卷 270-279页

作者： Bao, Zhiwei Wang, Qiang Du, Fengjun Key laboratory for Metallogenic Dynamics Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China Key laboratory of Isotope geochronology Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China Henan Institute of Geological Survey Zhenzhou 450007 China

The Longwangzhuang granite pluton occurs on the southern margin of the North China Craton and consists mainly of biotite syenogranite with aegirine granite being locally *** granites are characterized by high silicon and alkaline contents(SiO2=72.17%-76.82%,K2O+Na2O=8.28%-10.22%,K2O/Na2O>>1),AI(agpaitic index) =0.84-0.95,DI=95-97,ASI(aluminum saturation index)=0.96-1.13,and very high Fe* number(FeO*/(FeO*+Mg)=0.90-0.99),thus the granites are assigned to the metaluminous to weakly peraluminous,alkalic to calc-alkalic ferroan A-type *** granites are rich in large ion lithophile elements(LILE),especially high in REE concentrations(REE+Y=854×10-6-1572×10-6);whereas the enrichment of high strength field elements(Nb,Ta,Zr,Hf) is obviously less than that of LILEs,exhibiting mild depletions on trace element spider plots;and the rocks are significantly depleted in Ba,Sr,Ti,and *** low εNd(t) values(-4.5--7.2) and high model ages(2.3-2.5 Ga) of the granites as well as the low εHf(t) values(-1.11--5.26) and high Hf model ages(THf1= 2.1-2.3 Ga,THf2=2.4-2.6 Ga) of zircons from the biotite syenogranite suggest that the granites were probably derived from an enriched mantle *** zircons from the biotite syenogranite are mainly colorless transparent crystals exhibiting well-developed oscillatory zoning on the cathodoluminescence images with a LA-ICPMS zircon U-Pb age of 1602.1±6.6 Ma(MSWD=0.48).Petrochemical,trace elements,as well as Nd and Hf isotopic compositions of the rocks demonstrate that the granites were formed in a within-plate extensional tectonic regime possibly related to the breakup of the Columbia *** granites were most likely formed through extreme fractional crystallization of alkali basaltic magma resulted from partial melting of the mantle,which was fertilized by recycling crustal rocks triggered by the delamination of lithospheric mantle and lower crust following the ～1.8 Ga collision and amalgamation of the North Chin

关键词： syenogranite rare earth isotope geochemistry Proterozoic Columbia supercontinent

Rock Deformation,Component Migration and 18O/16O Variations during Mylonitization in the Southern Tan-Lu Fault Belt

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Acta Geologica Sinica(English Edition) 2007年第2期81卷 297-311页

作者： YANG Xiaoyong LIU Deliang FENG Min YU Qingni WANG Kuiren CAS Key laboratory of Crust-Mantle Materials and Environments School of Earth and Space Sciences University of Science and Technology of China Hefei Anhui 230026 CAS Key laboratory of Isotope geochronology and Geochemistry Guangzhou Institute of Geochemistry Guangzhou Guangdong 510640

This paper discusses the relationship between the volume loss, fluid flow and component variations in the ductile shear zone of the southern Tan-Lu fault belt. The results show that there is a large amount of fluids flowing through the shear zone during mylonitization, accompanied with the loss of volume of rocks and variations of elements and oxygen isotopes. The calculated temperature for mylonitization in different mylonites ranges from 446 to 484℃, corresponding to that of 475 to 500℃ for the wall rocks. The condition of differential stress during mylonization has been obtained between 99 and 210 MPa, whereas the differential stress in the wall rock gneiss is 70-78 MPa. The mylonites are enriched by factors of 1.32-1.87 in elements such as TiO2, P2O5, MnO, Y, Zr and V and depleted in SiO2, Na2O, K2O, Al203, Sr, Rb and light REEs compared to their protolith gneiss. The immobile element enrichments are attributed to enrichments in residual phases such as ilmentite, zircon, apatite and epidote in mylonites and are interpreted as due to volume losses from 15% to 60% in the ductile shear zone. The largest amount of SiO2 loss is 35.76 g/100 g in the ductile shear zone, which shows the fluid infiltration. Modeling calculated results of the fluid/rock ratio for the ductile shear zone range from 196 to 1192 by assuming different degrees of fluid saturation. Oxygen isotope changes of quartz and feldspar and the calculated fluid are corresponding to the variations of differential flow stress in the ductile shear zone. With increasing differential flow stress, the mylonites show a slight decrease of δ^18O in quartz, K-feldspar and fluid.

关键词： mylonitization ductile shear zone component migration oxygen isotopes southern Tan- Lu fault belt

Mass and isotopic concentrations of water-insoluble refractory carbon in total suspended particulates at *** Observatory(China)

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Particuology 2015年第3期13卷 24-31页

作者： Xiangdong Zheng Chengde Shen Guojiang Wan Jie Tang Kexin Liu Key laboratory of Atmospheric Chemistry Chinese Academy of Meteorological Sciences State Key laboratory of Isotope geochronology and Geochemistry Guangzhou Institute of GeochemistryChinese Academy of Sciences State Key laboratory of Environment Geochemistry Institute of GeochemistryChinese Academy of Sciences Center of Meteorological Sounding Chinese Meteorological Administration State Key laboratory of Nuclear Physics and Technology and Institute of Heavy Ion Physics Peking University

Mass concentration and isotopic values δ13C and 14C are presented for the water-insoluble refractory carbon （WIRC） component of total suspended particulates （TSP）, collected weekly during 2003, as well as from October 2005 to May 2006 at the WMO-GAW Mt. Waliguan （WLG） site. The overall average WlRC mass concentration was （1183 ± 120）ng/m3 （n = 79）, while seasonal averages were 2081 ± 1707 （spring）, 454±205 （summer）, 650 ±411 （autumn）, and 1019 ± 703 （winter） ng/m3. Seasonal variations in WIRC mass concentrations were consistent with black carbon measurements from an aethalometer, although WIRC concentrations were typically higher, especially in winter and spring. The δ13C PDB value （-25.3 ± 0.8）%0 determined for WIRC suggests that its sources are C3 biomass or fossil fuel combustion. No seasonal change in δ13C PDB was evident. The average percent Modern Carbon （pMC） for 14C in WIRC for winter and spring was （67.2 ± 7.7）% （n = 29）. Lower pMC values were associated with air masses trans- ported from the area east of WLG, while higher pMC values were associated with air masses from the Tibetan Plateau, southwest of WLG. Elevated pMC values with abnormally high mass concentrations of TSP and WIRC were measured during a dust storm event.

关键词： Water-insoluble refractory carbon (WIRC)Mass concentration813C14CMt. Waliguan (WLG)

A putative greigite-type magnetosome gene cluster from the candidate phylum Latescibacteria

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A putative greigite-type magnetosome gene cluster from the c...

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： Wei Lin Yongxin Pan Biogeomagnetism Group Paleomagnetism and Geochronology Laboratory Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of Sciences France-China Bio-Mineralization and Nano-Structures laboratory Chinese Academy of Sciences

The intracellular biomineralization of magnetite and/or greigite magnetosomes in magnetotactic bacteria(MTB) is strictly controlled by a group of conserved genes, termed magnetosome genes, which are organized as clusters(or islands) in MTB genomes. So far, all reported MTB are affiliated within the Proteobacteria phylum, the Nitrospirae phylum and the candidate division OP3. Here, we report the discovery of a putative magnetosome gene cluster structure from the draft genome of an uncultivated bacterium belonging to the candidate phylum Latescibacteria(formerly candidate division WS3)recently recovered by Rinke and colleagues, which contains 10 genes with homology to magnetosome mam genes of magnetotactic Proteobacteria and Nitrospirae. Moreover, these genes are phylogenetically closely related to greigite-type magnetosome genes that were only found from the Deltaproteobacteria MTB before, suggesting that the greigite genes may originate earlier than previously imagined. These findings indicate that some members of Latescibacteria may be capable of forming greigite magnetosomes, and thus may play previously unrecognized roles in environmental iron and sulfur cycles. The conserved genomic structure of magnetosome gene cluster in Latescibacteria phylum supports the hypothesis of horizontal transfer of these genes among distantly related bacterial groups in nature.

关键词：

Newly Isolated but Uncultivated Magnetotactic Bacterium of the Phylum Nitrospirae from Beijing,China

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Newly Isolated but Uncultivated Magnetotactic Bacterium of t...

中国科学院地质与地球物理研究所2012年度（第12届）学术年会

作者： Wei Lin Jinhua Li Yongxin Pan Biogeomagnetism Group Paleomagnetism and Geochronology LaboratoryKey Laboratory of the Earth’s Deep InteriorInstitute of Geology and GeophysicsChinese Academy of Sciencesand France-China Bio-Mineralization and Nano-Structures LaboratoryChinese Academy of Sciences

Magnetotactic bacteria(MTB) in the phylum Nitrospirae synthesize up to hundreds of intracellular bullet-shaped magnetite *** the present study,a watermelon-shaped magnetotactic bacterium(designated MWB-1) from Lake Beihai in Beijing,China,was *** uncultivated microbe was identified as a member of the phylum Nitrospirae and represents a novel phylogenetic lineage with≥6%16S rRNA gene sequence divergence from all currently described ***-1

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Using a Gaussian mathematical model to define eruptive stages of young volcanic rocks in Tengchong based on laser 40Ar/39Ar dating

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Science China Earth Sciences 2020年第5期63卷 662-673页

作者： Xinwei ZHAO Jing ZHOU Fang MA Jianqing JI Alan DEINO School of Earth Sciences and Resources China University of GeosciencesBeijing 100083China Key laboratory of Orogenic Belts and Crustal Evolution School of Earth and Space SciencesPeking UniversityBeijing 100871China Berkeley geochronology Center Berkeley CA94709USA

Reconstruction of Quaternary environments,late Cenozoic geodynamics and evaluation of volcanic hazards,all depend on the precise delineation of eruptive *** recent years,laser 40Ar/39Ar dating methods have been widely used for dating young volcanic rocks,given their stable automated testing process,very low background level and high sensitivity,which meet the requirements for precise dating of young *** paper applied high-precision laser 40Ar/39Ar dating to the main volcanic units in the Tengchong area and obtained ages in the range of 0.025–5.1 Ma using conventional data processing ***,conventional dating highlighted issues related to very low radiogenic 40Ar content,accidental errors and poor data stability,which led to huge age ***,lacking a unified timescale,conventional methods were unable to strictly define the stages of the Tengchong volcanic eruptions,leading to ongoing *** this study,we applied a Gaussian mathematical model to deal with all 378 original ages from 13 *** apparent age-probability diagram,consisting of three independent waveforms,have been *** corresponding isochron ages of these three waveforms suggest there were three volcanic eruptive stages,namely during the Pliocene(3.78±0.04 Ma),early Middle Pleistocene(0.63±0.03 Ma)and late Middle Pleistocene to early Late Pleistocene(0.139±0.005 Ma).These results accurately define eruptive stages in the Tengchong area.

关键词： Laser 40Ar/39Ar dating Gaussian mathematical model Eruptive stages Apparent age-probability diagram Age deviations Isochron age

A biogeographic distribution of magnetotactic bacteria influenced by salinity

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A biogeographic distribution of magnetotactic bacteria influ...

中国科学院地质与地球物理研究所2012年度（第12届）学术年会

作者： Wei Lin Yinzhao Wang Bi Li Yongxin Pan Biogeomagnetism Group Paleomagnetism and Geochronology LaboratoryKey Laboratory of the Earth's Deep InteriorInstitute of Geology and GeophysicsGhinese Academy of Sciences France-China Bio-Mineralization and Nano-Structures laboratory Chinese Academy of Sciences

Magnetotactic bacteria(MTB),which synthesize intracellular ferromagnetic magnetite and/or greigite magnetosomes,have significant roles in global iron cycling in aquatic systems,as well as sedimentary *** occurrence of MTB has been reported in aquatic environments from freshwater to marine ecosystems;however,the distribution of MTB across heterogeneous habitats remains *** we examined the MTB communities from diverse habitats across northern and southern China,using comprehensive transmission electron microscopy and comparison of 16S rRNA gene analyses.A total of 334 16S rRNA gene sequences were analyzed,representing the most comprehensive analysis on the diversity and distribution of MTB to *** majority(95%) of sequences belong to the Alphaproteobactena,whereas a population of giant magnetotactic rod is affiliated with the Nitrospirae *** a statistical comparison of these sequence data and publicly available MTB sequences,we infer for the first time that the composition of MTB communities represents a biogeographic distribution across globally heterogeneous environments, which is influenced by salinity.

关键词： magnetotactic bacteria biogeography microbial diversity salinity

Environmental Factors Affect Magnetite Magnetosome Synthesis in Magnetospirillum magneticum AMB-1:Implications for Biologically Controlled Mineralization

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Environmental Factors Affect Magnetite Magnetosome Synthesis...

中国科学院地质与地球物理研究所2012年度（第12届）学术年会

作者： Jinhua Li Yongxin Pan Bio-geomagnetism Group Paleomagnetism and Geochronology LaboratoryKey Laboratory of Earth's Deep InteriorInstitute of Geology and GeophysicsChinese Academy of Sciences France-China Bio-Mineralization and Nano-Structures laboratory Chinese Academy of Sciences

It is widely believed that magnetotactic bacteria(MTB) form membrane-enveloped magnetite crystals(magnetosomes) under strict genetic *** this study,the Magnetospirillum magneticum strain AMB-1 was cultured in the same growth medium, but under four different growth conditions:Anaerobic static,aerobic static,aerobic 80-rpm rotating,and aerobic 120-rpm rotating to investigate possible environmental influences on magnetite magnetosome *** analyses,using transmission electron microscopy,X-ray diffraction and rock magnetism,indicate that, from the anaerobic static to aerobic 120-rpm rotating culture,the formed magnetite magnetosomes became more equidimensional, smaller in grain size,and higher in crystal twinning frequency. Magnetic properties of magnetite magnetosomes such as coercivity, remanence coercivity,remanence ratio and Verwey transition temperature systematically decreased from 22.0 mT to 5.2 mT, 31.3 mT to 9.3 mT,0.45 to 0.31,and 108 K to 98 K,respectively. Comparison of additional anaerobic 120-rpm rotating cultures with anaerobic static cultures showed that the effect of rotating, at least up to 120 rpm,on the cell growth and magnetite magnetosome formation is weak and *** that all samples were prepared and measured in the same way,the changes in physical and magnetic properties indicate that environmental factors(oxygen) affected the biomineralization of magnetite magnetosomes in magnetotactic bacteria,which supports the previous *** all experiments,only magnetite with the geometry of truncated octahedron was formed within magnetosomes,which suggests that the mineral phase and crystal habit remain to be genetically controlled. These results also imply the physical and magnetic properties of magnetite magnetosomes may,to some extent,reflect the external growth environments.

关键词： magnetotactic bacteria M.magneticum AMB-1 environmental factor biologically controlled mineralization rock magnetism

Origin of Cu in the PACMANUS hydrothermal field from the eastern Manus back-arc basin: evidence from mass balance modeling

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Acta Oceanologica Sinica 2019年第9期38卷 59-70页

作者： Yao Ma Xiaoyuan Wang Shuai Chen Xuebo Yin Bowen Zhu Kun Guo Zhigang Zeng Key laboratory of Marine Geology and Environment Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China laboratory for Marine Mineral Resources Pilot National Laboratory for Marine Science and Technology (Qingdao) Qingdao 266071 China University of Chinese Academy of Sciences Beijing 100049 China Ocean Science Isotope and geochronology Center Pilot National Laboratory for Marine Science and Technology (Qingdao) Qingdao 266071 China

Hydrothermal precipitates associated with active vents in the eastern Manus Basin, an actively opening back-arc basin in the Bismarck Sea, Papua New Guinea, are among the most Cu-rich on the modern seafloor. The volcanic rocks associated with this mineralization may be insufficiently enriched in Cu to account for the Cu content of the sulfides by simple leaching. The PACMANUS hydrothermal field lies in the eastern portion of the eastern Manus Basin. Mass balance modeling of the PACMANUS hydrothermal system indicates that simple leaching of a stationary reaction zone (0.144 km^3) by hydrothermal fluids cannot yield the Cu found in associated sulfide deposits because unacceptably high leaching, transportation and precipitation efficiencies are required to derive the Cu in sulfides by leaching processes. With 100% leaching, transport and precipitating efficiency, 0.166 km^3 of volcanic rocks would need to be leached to account for the Cu budget of hydrothermal sulfide deposits. The key requirement for forming metal-rich magmatic fluids is a large amount of metals available to enter the exsolved vapor phase. Magmas generated in the eastern Manus Basin inherently have high fO2 because of metasomatism of the mantle source by oxidized materials from the subducted slab, leading to copper enrichment in the magma chamber. Moreover, the presence of Cu in gas-rich melt inclusi on bubbles in Pual Ridge andesite is evidence that degassing and partitioning of Cu into the magmatic volatile phase has occurred in the eastern Manus Basin. Numerical mass balance modeling indicates that approximately 0.236 Mt Cu was potentially transferred to the hydrothermal system per cubic kilometer magma. Magmatic degassing seems to play a more significant role than leaching.

关键词： back-arc basin mass balance model PACMANUS hydrothermal field source of Cu