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Syn-collision Biotite Hornblende Granodiorite from the Zedong Area,Tibet:Zircon U–Pb Isotope Chronology,Petro-geochemistry,and Geodynamic Significance

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Acta Geologica Sinica(English Edition) 2017年第2期91卷 515-529页

作者： ZHU Feilin SHI Zeming XIONG Fuhao ni shijun BAI Mei College of Earth Science Chengdu University of TechnologyChengdu 610059SichuanChina Applied Nuclear Technology in Geosciences Key Laboratory of Sichuan Province(Chengdu University ofTechnology) Chengdu 610059SichuanChina Geological Survery lnstitute Chengdu University of TechnologyChengdu 610059SichuanChina

Cu–Au mineralization is rare in the Jurassic–Early Tertiary batholiths related to the India–Asia collision. Geochemical analysis and U–Pb isotope chronology was carried out on Shuangbujiere biotite hornblende granodiorite from the Zedong area. Zircon grains of the biotite hornblende granodiorite show oscillatory growth zonation and have high Th/U ratios of 1.08–2.39, indicating a magmatic origin for the zircons. Geochrological test yielded a LA-ICP-MS U-Pb age of 51.5±1.0 Ma, suggesting that the emplacement age of the biotite hornblende granodiorite is Early Eocene. The Shuangbujiere biotite hornblende granodiorites have geochemical features characteristic of adakite and are associated with a calc–alkaline metaluminous I-type granite enriched in Sr, high in Mg~#（49.6–54.9） and Sr/Y, and depleted in Y and Yb. These results indicate that this intrusion formation may have been associated with crustal thickening caused by the early collision of the Indian and Eurasian Plates. As the process of crustal thickening continued, the heating of the underplated basaltic magma caused the thickened lower crust amphibolite to dehydrate the melt and form a high-K calc–alkaline adakitic melt at about 848°C. Meanwhile, magma mixing of the underplated basaltic melt and high-K calc–alkaline adakitic melt formed a high-Mg# adakite representative of the sys-collisional tectonic setting.

关键词： chronology adakite thickened lower crust Zedong orefield Gangdese Tibet Proto-Tethys

Evolution of isotopic composition and deuterium excess of brines in the Sichuan Basin, China

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Chinese Journal Of Geochemistry 2013年第1期32卷 69-77页

作者： YAN Qiushi GAO Zhiyou ni shijun SHI Zeming YIN Guan Geochemistry Department College of Nuclear Technology and Automatic Engineering Chengdu University of Technology

The isotopic composition and parameters for deuterium excess of brines, which were sampled in the Si-chuan Basin, show obvious regularities of distribution. The brine isotopic composition shows distinct two systems of marine and terrestrial deposits, with the Middle Triassic strata as the boundary. Brine hydrogen isotopic composition of marine deposits is lower while oxygen isotopic composition is higher than that of the SMOW, respectively, indicating that the brines were derived from seawater with different evaporating degrees at different times. From the Sinian strata, up to the Cambrian, Permian Maokou Formation and the Triassic Jialingjiang Formation, the δD values of brines tend to become relatively positive with the strata becoming younger. Brines of terrestrial deposits are considered to have been derived from precipitation and their isotopic composition is close to the globe meteoric water line (GMWL). Brines of transitional deposits between marine and terrestrial ones (the Upper Triassic Xujiahe Formation) have δD and δ18O values falling between the two end members of marine deposit brines and precipitation, indicating that the brines are a mixture of precipitation and vaporing seawater. Water samples from the brine-bearing strata of different ages show various deuterium excesses (d) with an evident decreasing trend as the age of strata gets older and older. Brine-bearing strata of the Triassic Leikoupo-Jialingjiang Formation, the Permian Maokou Formation, the Cambrian and Sinian strata are all carbonate rocks which have experienced intensive water/rock reaction and the deuterium excess essentially changes with time. All brine-bearing-strata surrounding the basin or faults, as well as those brine wells exploited for resources, have been obviously influenced by the precipitation supply. Therefore, the deuterium excesses of their brines have increased to different extents, depending on the amount of involvement of meteoric water. The variation and distributio

关键词：同位素组成四川盆地过量氘卤水震旦纪地层演变中国陆相沉积

New Evidence for Genesis of the Zoige Carbonate-Siliceous-Pelitic Rock Type Uranium Deposit in Southern Qinling:Discovery and Significance of the 64 Ma Intrusions

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Acta Geologica Sinica(English Edition) 2014年第6期88卷 1757-1769页

作者： SONG Hao ZHANG Chengjiang ni shijun XU Zhengqi HUANG Changhua Department of Geochemistry Chengdu University of Technology Key Laboratory of Nuclear Techniques in Geosciences of Sichuan Province Sichuan Nuclear Geology Institute

The carbonaceous-siliceous-argillitic rock type uranium deposit in the Zoige area is located in the northeastern margin of the Tibetan Plateau, and has gained much attention of many geologists and ore deposit experts due to its scale, high grade and abundant associated ores. Because of the insufficient reliable dating of intrusive rocks, the relationship between mineralization and the magmatic activities is still unknown. In order to study this key scientific issue and the ore-forming processes of the Zoige uranium ore field, the LA-ICP-MS zircon U-Pb dating of magmatic rocks was obtained：64.08±0.59 Ma for the granite-prophyry and ~200 Ma for the dolerite. U-Pb dating results of uraninite from the Zoige uranium ore field are mainly concentrated on ~90 Ma and ~60 Ma. According to LA-ICP-MS U-Pb zircon dating, the ages for the dolerite, porphyry granite and granodiorite are 200 Ma, 64.08 Ma approximately and 226.5-200.88 Ma, respectively. This indicates that the mineralization has close relationship with activities of the intermediate-acidic magma. The ages of the granite porphyry are consistent with those uraninite U-Pb dating results achieved by previous studies, which reflects the magmatic and ore-forming event during the later Yanshanian. Based on the data from previous researches, the ore bodies in the Zoige uranium ore field can be divided into two categories：the single uranium type and the uranium with polymetal mineralization type. The former formed at late Cretaceous（about 90 Ma）, while the latter, closely related to the granite porphyry, formed at early Paleogene（about 60 Ma）. And apart from ore forming elemental uranium, the latter is often associated with polymetallic elements, such as molybdenum, nickel, zinc, etc.

关键词： LA-ICP-MS U-Pb Carbonaceous-siliceous-pelitic rock type uranium deposits mineralization mechanism Zoige

Influence on electron energy loss spectroscopy of the niobium-substituted uranium atom:A density functional theory study

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Nuclear Science and Techniques 2008年第6期19卷 365-369页

作者： LU Chunhai ni shijun CHEN Wenkai ZHANG Chengjiang WANG Yongli National Key Laboratory for Surface Physics and Chemistry Mianyang 621907 China Sichuan Provincial Key Laboratory for Applied Nuclear Technology in Geology Chengdu University of Technology Chengdu 610059 China Department of Chemistry Fuzhou University Fuzhou 350002 China

We present the electronic structure and electron energy loss spectroscopy (EELS) for uranium, niobium and U3Nb in which uranium is substituted by niobium. Comparing the electronic structures and optical properties for uranium, niobium and U3Nb, we found that when niobium atom replaces uranium atom in the center lattice, density of state (DOS) of U3Nb shifts downward to low energy. niobium affects DOS for f and d electrons more than that for p and s electrons. U3Nb is similar to uranium for the electronic energy loss spectra.

关键词：铀铌电子能损耗光谱电子构造局部密度近似值

Geochemical Tracing of Ore-forming Material Sources of Carlin-type Gold Deposits in the Yunnan-Guizhou-Guangxi Triangle Area --A Case Study of the Application of the Combined Silicon Isotopes Geochemistry and Siliceous Cathodoluminescence Analysis

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Acta Geologica Sinica(English Edition) 1999年第1期73卷 30-39页

作者： LIU Xianfan ni shijun LU Qiuxia JIN Jingfu ZHU Laimin 1. Open Lab of Ore Deposits Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 2. Chengdu Institute of Technology Chengdu 610059

Abstract This paper deals with characteristics of silicon isotope compositions and siliceous cathodoluminescence of host rocks, ores and hydrothermal silicified quartz of the Carlin-type ore deposits in the Yunnan-Guizhou-Guangxi triangle area. The study shows that primary silicified quartz is nonluminescent but quartz in host rocks and secondary silicified quartz are luminescent by the action of cathode rays. Correspondingly, silicon isotope compositions of host rocks, ores and hydro6thermal quartz veins are clearly distinguished. In strata from the Middle Triassic to the “Dachang” host bed, δ30Si of the host rocks ranges from 0.0% ?0.3%, while that of primary ore-forming silicified fluids from ?0.1% to ?0.4%; in the Upper Permian and Lower Carboniferous strata and Indosinian diabase host beds, δ30Si of the host rocks is from ?0.1% to ?0.2% and that of the primary silicified quartz veins from 0.3 % ?0.5 %. This pattern demonstrates the following geochemical mineralization process, primary ore-forming siliceous fluids migrated upwards quickly along the main passages of deep-seated faults from mantle to crust and entered secondary faults where gold deposits were eventually formed as a result of permeation and replacement of the siliceous ore-forming fluids into different ore-bearing strata. This gives important evidence for the fact that ore-forming fluids of this type of gold deposits were mainly derived from upper mantle differentiation and shows good prospects for deep gold deposits and geochemical background for large and superlarge gold deposits.

关键词： silicon isotope siliceous cathodoluminescence tracing of ore-forming material source Carlin-type gold deposit Yunnan-Guizhou-Guangxi triangle area

On the Mechanism of Transformation fromPrimary Ores into Oxidized Ores in FinelyDisseminated Gold Deposits

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Acta Geologica Sinica(English Edition) 1998年第3期72卷 291-298页

作者： LIU Xianfan ni shijun JIN Jingfu LU Qiuxia ZHANG Xingchun Open Lab of Ore Deposits Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang Guizhou 550002 Chengdu Institute of Technology Chengdu Sichuan 610059

: This paper, taking the finely disseminated gold deposits in southwestern Guizhou and northwestern Guangxi as examples, discusses the difference between the occurrence of primary ores and that of oxidized ores, analyzes the occurrence mechanism in terms of crystallochemistry and geochemistry, and especially studies the chemical model for supergene leaching transformation of clay minerals in the two types of ores. This study proposes a new idea for dressing and smelting technology for primary gold ores.

关键词： occurrence of gold ore clay minerals supergene leaching transformation chemical model

Differential Effects of Ammonium and nitrate on Growth Performance of Glechoma longituba under Heterogeneous Cd Stress

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Phyton-International Journal of Experimental Botany 2020年第3期89卷 667-679页

作者： Yanwei Feng Wen Lei Rui Gu Ping Zhao shijun ni ningfei Lei College of Earth Sciences Chengdu University of TechnologyChengdu610101China College of Landscape Architecture Sichuan Agricultural UniversityChengdu610101China College of Environment Chengdu University of TechnologyChengdu610101China Geological Party 105 Guizhou Provincial Bureau of Geology and Mineral Exploration and DevelopmentGuiyang550018China

Water,minerals,nutrients,etc.,can be shared by physiological integration among inter-connected ramets of clonal *** plays an important role in alleviating cadmium(Cd)stress for clonal *** how different forms of nitrogen affect growth performance of clonal plants subjected to heterogeneous Cd stress still remains poorly understood.A pot experiment was conducted to investigate the differential effects of ammonium and nitrate on growth performance of Glechoma longituba under heterogeneous Cd *** the experiment,parent ramets of Glechoma longituba clonal fragments were respectively supplied with modified Hoagland solution containing 7.5 mM ammonium,7.5 mM nitrate or the same volume of nutrient solution without *** solution with different concentrations(0,0.1 or 2.0 mM)was applied to offspring ramets of the clonal *** with control(N-free),nitrogen addition to parent ramets,especially ammonium,significantly improved antioxidant capacity[glutathione(GSH),proline(Pro),peroxidase(POD,)superoxide dismutase(SOD)and catalase(CAT)],PSII activity[maximum quantum yield of PSII(F_(v)/F_(m))and effective quantum yield of PSII(ΦPSII)],chlorophyll content and biomass accumulation of the offspring ramets suffering from Cd *** addition,negative effects of nitrate on growth performance of whole clonal fragments were observed under Cd stress with high concentration(2.0 mM).Transportation or sharing of nitrogen,especially ammonium,can improve growth performance of clonal plants under heterogeneous Cd *** experiment provides insight into transmission mechanism of nitrogen among ramets of clonal plants suffering from heterogeneous nutrient *** integration might be an important ecological strategy for clonal plants adapting to heterogeneous environment stress conditions.

关键词： Clonal plant physiological integration nitrogen form antioxidant capacity chlorophyll fluorescence

Assessment of heavy metals contamination in soils of Dexing region, Jiangxi Province, China

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Chinese Journal Of Geochemistry 2006年第B08期25卷 27-28页

作者： Cuihua CHEN shijun ni Binbin HE Chengjiang ZHANG School of Geosciences Chengdu University of Technology Chengdu 610059 China School of Applied Nuclear Techniques ＆ Automatic Engineering Chengdu University of Technology Chengdu 610059 China Institute of Geo-Spatial Information Science and Technology University of Electronic Science and Technology of China Chengdu 610054 China

Simulation of Water-Rock Reaction Theory of Gold Ore in Gansu Dashui

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Simulation of Water-Rock Reaction Theory of Gold Ore in Gans...