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| 1 | Petrogenesis of the Xihuashan Granite in Southern Jiangxi Province,South China:Constraints from Zircon U-Pb Geochronology,Geochemistry and Nd Isotopes显示文摘Mesozoic granitic intrusions are widely distributed in the Nanling region,South China.Yanshanian granites are closely connected with the formation of tungsten deposits.The Xihuashan granite is a typical representative of tungsten-bearing granite.The Xihuashan granite consists mainly of medium-grained porphyritic biotite granite,medium-grained biotite granite and fine-grained two-mica granite,which correspond to LA-ICP-MS zircon U-Pb ages of 155.5±0.4 Ma,153.0±0.6 Ma and 152.8±0.9 Ma,respectively.Rocks from the Xihuashan mining area displays high SiO2(73.85% to 76.49%) and Na2O+K2O contents(8.09% to 9.43%),belonging to high-K calc-alkaline series.They are metaluminous to weakly peraluminous with A/CNK values ranging from 0.96 to 1.06.All granites in this study area are rich in Rb,Th,U and Pb,and depleted in Ba,Sr,P,Ti,Nb and Eu,especially depleted in medium-grained biotite granite and fine-grained two-mica granite.The medium-grained porphyritic biotite granites usually have high LREE concentrations,whereas medium-grained biotite granite and fine-grained two-mica granite displays high HREE contents.Our geochemical data reveal that the studied rocks are highly fractionated I-type granite.The magma underwent strong magma differentiation with decreasing temperature and increasing oxygen fugacity,which may explain the formation of three types of distinct granites.Variations of Rb,Sr and Ba concentrations in different type granites were controlled by fractional crystallization of biotite and feldspar.Fractional crystallization of monazite,allanite and apatite resulted in LREE changes in granite,and formation of garnet mainly caused HREE changes.Granites from the Xihuashan mining area have relatively high εNd(t) values(-9.77 to -11.46),indicating that they were probably generated by partial melting of underlying Proterozoic metasedimentary rocks with minor addition of juvenile crust or mantle-derived magmas. | YANG Jiehua PENG Jiantang ZHAO Junhong FU Yazhou YANG Chen HONG Yinglong | 2012 | Acta Geologica Sinica(English Edition)2012，86，1： | 17 |
| 2 | Os isotopic compositions of a cobalt-rich ferromanganese crust profile in Central Pacific显示文摘187Os/188Os ratios in all sub-layers of the Co-rich ferromanganese crust MP5D17 from Line Seamount in Central Pacific have been systematically determined. The 187Os/188Os values in this crust are highly variable, ranging from 0.4262 to 1.0155. From the bottom to the top, the os-mium isotopic ratios of the crust display a regular variation trend, which correlates well with its changes in structure and texture in the vertical profile. In comparison with the evolu-tion curve of Os isotopic composition in seawater over the past 80 Ma, a similar evolution tendency can be found with respect to the Os isotopic composition of the crust in this study. It is preliminarily concluded that the crust MP5D17 began to grow at about 72 Ma, and underwent three growth hiatuses, corresponding to the geological ages of 64, 53 and 37 Ma, respectively. | FU Yazhou PENG Jiantang QU Wenjun HU Ruizhong SHI Xuefa DU Andao | 2005 | Chinese Science Bulletin2005，50，18： | 13 |
| 3 | The metallogenic environment of the Dounan manganese deposit,Southeast Yunnan, China: evidence from geochemistry and Mössbauer spectroscopic显示文摘The Dounan manganese deposit is a typical large-scale marine sedimentary manganese deposit of the Middle Triassic in China. The metallogenic environment and change process directly dictate the migration, enrichment, and precipitation of Mn. To better understand its metallogenetic environment, a detailed study was undertaken involving field observation, mineralogical and geochemical and M?ssbauer spectroscopic analyses. The major findings are as follows:(1) Lithofacies paleogeography, sedimentary structural characteristics, and geochemical indexes indicate that the deposits were formed in an epicontinental marine sedimentary basin environment of normal salinity;(2) there were three ore phases including Mn oxides, Mn carbonates, and mixed Mn ores. The ore minerals found were braunite, manganite, Ca-rhodochrosite, manganocalcite, and kutnahorite. Petrographic and mineralogical information indicates that the metallogenic environment was a weakly alkaline and weakly oxidized to weakly reduced environment, and the mineralization occurred near the redox interface;(3) the V/(V + Ni)ratios, δCe and Fe^(2+)/Fe^(3+) found in profiles of Baigu and Gake ore sections show that the redox conditions of the ore-forming environment were continuously changing; and(4) three Fe species, α-Fe_2O_3, para-Fe^(3+), and para-Fe^(2+),were found in hematite and clay mineral samples using M?ssbauer spectrum analysis. The presence and distribution of these Fe species indicate that the deposit was formed in a typical sedimentary environment during the mineralization process. In summary, our study showed that redox was a key factor controlling the mineralization of the Dounan manganese deposit. Our results have led us to the conclusion that transgression and regression caused fluctuations in sea level, which in turn caused the change of the redox environment. M?ssbauer spectroscopy is an effective tool for studying the redox conditions of the paleoenvironment in which sedimentary manganese deposits were formed. | Jianbing Duan Yazhou Fu Zhengwei Zhang Xiangxian Ma Jiafei Xiao | 2019 | Acta Geochimica2019，38，1： | 1 |
| 4 | Subcellular localization and functional analyses of a PR10 protein gene from Vitis pseudoreticulata in response to Plasmopara viticola infection显示文摘 | Mingyang He Yan Xu Jiangling Cao Ziguo Zhu Yuntong Jiao Yuejin Wang Xin Guan Yazhou Yang Weirong Xu Zhenfang Fu | 2013 | Protoplasma2013，，1： | 1 |
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