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Highly fractionated granites:Recognition and research

Science China Earth Sciences 2017年第7期60卷 1201-1219页

作者： WU FuYuan LIU XiaoChi ji weiqiang WANG jiaMin YANG Lei State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Chinese Academy of Sciences Center for Excellence in Tibetan Plateau Earth Sciences Beijing 100101 China College of Earth Sciences University of Chinese Academy of Sciences Beijing 100049 China

Granite is one of the most important components of the continental crust on our Earth; it thus has been an enduring studied subject in geology. According to present knowledge, granite shows a great deal of heterogeneity in terms of its texture,structure, mineral species and geochemical compositions at different scales from small dike to large batholith. However, the reasons for these variations are not well understood although numerous interpretations have been proposed. The key point of this debate is whether granitic magma can be effectively differentiated through fractional crystallization, and, if so, what kind of crystallization occurred during the magmatic evolution. Although granitic magma has high viscosity because of its elevated SiO2 content, we agree that fractional crystallization is effectively processed during its evolution based on the evidence from field investigation,mineral species and its chemical variations, and geochemical compositions. These data indicate that crystal settling by gravitation is not the only mechanism dominating granitic differentiation. On the contrary, flow segregation or dynamic sorting may be more important. Accordingly, granite can be divided into unfractionated, fractionated(including weakly fractionated and highly fractionated) and cumulated types, according to the differentiation degree. Highly fractionated granitic magmas are generally high in primary temperature or high with various volatiles during the later stage, which make the fractional crystallization much easier than the common granitic melts. In addition, effective magmatic differentiation can be also expected when the magma emplaced along a large scale of extensional structure. Highly fractionated granitic magma is easily contaminated by country rocks due to its relatively prolonged crystallization time. Thus, granites do not always reflect the characteristics of the source areas and the physical and chemical conditions of the primary magma. We proposed that h

关键词： Fractional crystallization Accumulation Highly fractionated granite Granitic magma Continental crustal evolution

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The Langjiexue Group is an in situ sedimentary sequence rather than an exotic block: Constraints from coeval Upper Triassic strata of the Tethys Himalaya(Qulonggongba Formation)

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Science China Earth Sciences 2019年第5期62卷 783-797页

作者： Zhongyu MENG jiangang WANG weiqiang ji Hao ZHANG Fuyuan WU Eduardo GARZANTI Institute of Geology and Geophysics Chinese Academy of Sciences University of Chinese Academy of Sciences Laboratory for Provenance Studies Department of Earth and Environmental Sciences Università di Milano-Bicocca

The Upper Triassic Langjiexue Group in southeastern Tibet has long been an enigmatic geological unit. It belongs tectonically to the northern Tethys Himalayan zone, but provenance signatures of the detritus it contains are significantly different from those of typical Tethys Himalayan sandstones. Because the Langjiexue Group is everywhere in fault contact with Tethys Himalayan strata, its original paleogeographic position has remained controversial for a long time. According to some researchers, the Langjiexue Group was deposited onto the northern edge of the Indian passive continental margin, whereas others interpreted it as an independent block accreted to the northern Indian margin only during final India-Asia convergence and collision in the Paleocene. This study compares the Langjiexue Group and coeval Upper Triassic strata of the southern Tethys Himalayan zone(Qulonggongba Formation). Our new provenance data indicate that Qulonggongba Formation sandstones contain common felsic volcanic rock fragments, minor plagioclase, and euhedral to subhedral zircon grains yielding Late Paleozoic to Triassic ages. These provenance features compare well with those of the Langjiexue Group. Because the Qulonggongba Formation certainly belongs to the Tethys Himalayan zone, the provenance similarity with the Langjiexue Group indicates that the latter is also an in situ Tethys Himalayan sedimentary sequence rather than part of an exotic block. Volcanic detritus including Late Paleozoic to Triassic zircon grains in both Langjiexue Group and Qulonggongba Formation are interpreted to have been derived from the distant Gondwanide orogen generated by Pan-Pacific subduction beneath the southeastern margin of Gondwana. The Qulonggongba Formation, deposited above marlstones of the lower Upper Triassic Tulong Group, is overlain by India-derived coastal quartzose sandstones of the uppermost Triassic Derirong Formation. Deposition of both the Qulonggongba Formation and the Langjiexue Group

关键词： Tethys Himalaya Provenance analysis Langjiexue Group Detrital-zircon geochronology Tectonic setting Late Triassic Paleogeography

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Magnesium Microspheres and Nanospheres: Morphology- Controlled Synthesis and Application in Mg/MnO_(2) Batteries

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Nano Research 2009年第9期2卷 713-721页

作者： Chunsheng Li Fangyi Cheng weiqiang ji Zhanliang Tao Jun Chen Institute of New Energy Material Chemistry and Engineering Research Center of Energy Storage and Conversion(Ministry of Education) Nankai UniversityTianjin 300071China

In this paper,we report on the morphology-controlled synthesis of magnesium micro/nanospheres and their electrochemical performance as the anode of primary Mg/MnO_(2) *** micro/nanoscale materials with controllable shapes have been prepared via a conventional vapor-transport method under an inert atmosphere by adjusting the deposition *** analysis techniques including SEM,XRD,TEM/HRTEM,and Brunauer Emmett Teller(BET)were carried out to characterize the as-obtained *** results show that the Mg samples are microspheres or micro/nanospheres with specific surface areas of 0.611.92 m^(2)/*** electrochemical properties of the as-prepared Mg and commercial Mg powders were further studied in terms of their linear sweep voltammograms,impedance spectra,and discharge *** comparing the performance of different inhibitors in electrolytes,it was found that NaNO2(2.6 mol/L)as an inhibitor in the Mg(NO_(3))_(2)(2.6 mol/L)electrolyte affords a Mg electrode with high current density and low corrosion *** particular,the Mg sample consisting of microspheres with a diameter of 1.53.0μm and nanospheres with a diameter of 50150 nm exhibited superior electrode properties including negative initial potential(1.08 V),high current density(163 mA/cm^(2)),low apparent activation energy(5.1 kJ/mol),and high discharge specifi c capacity(784 mAh/g).The mixture of Mg nanospheres and microspheres is promising for application in primary Mg/MnO_(2) batteries because of the suffi cient contact with the electrolyte and greatly reduced charge transfer impedance and polarization.

关键词： Magnesium micro/nanospheres vapor-transport method primary Mg/MnO_(2)batteries

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MV-PID Controller for Linear Systems Subject to Input Constraint 36

MV-PID Controller for Linear Systems Subject to Input Constr...

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第36届中国控制会议

作者： ji weiqiang Huang Chunqing Liu Yunlong Department of Automation Xiamen University

ISBN: (纸本)9781538629185

Since PID controller is widely applied in control system and output variance is directly related to economic benefit of the real system,it has a desire for variance optimizing PID controller under input constraint in engineering ***-PID control is proposed in this paper and its tuning rule is derived *** the presence of input constraint,the proposed controller keeps the ability of step/constant disturbance rejection as general PID controller;and moreover,its variance performance is very close to that of the constrained *** example demonstrates the effectiveness of the proposed controller.

关键词： Input constraint MVC MV-PID output variance disturbance rejection

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Porous LiFePO_(4)/NiP Composite Nanospheres as the Cathode Materials in Rechargeable Lithium Ion Batteries

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Nano Research 2008年第3期1卷 242-248页

作者： Chunsheng Li Shaoyan Zhang Fangyi Cheng weiqiang ji Jun Chen Institute of New Energy Material Chemistry Key Laboratory of Energy Material Chemistry(Tianjin)and Engineering Research Center of High-Energy Storage and Conversion(Ministry of Education)Nankai UniversityTianjin 300071China

We report the synthesis of porous LiFePO4/NiP composite nanospheres and their application in rechargeable lithium-ion batteries.A simple one-step spraying technique was developed to prepare LiFePO_(4)/NiP composite nanospheres with an electrical conductivity 10^(3)-10^(4) times that of bulk particles of LiFePO_(4).Electrochemical measurements show that LiFePO_(4) nanospheres with a uniform loading of 0.86 wt%1.50 wt%NiP exhibit high discharge capacity,good cycling reversibility,and low apparent activation *** superior electrode performance of the as-prepared composite nanospheres results from the greatly enhanced electrical conductivity and porous structure of the materials.

关键词： Nanospheres LiFePO_(4)/NiP spraying electrical conductivity rechargeable lithium-ion batteries

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Chronology and Geochemistry of Volcanic Rocks in the Cretaceous Suifenhe Formation in Eastern Heilongjiang,China

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Acta Geologica Sinica(English Edition) 2007年第2期81卷 266-277页

作者： ji weiqiang XU Wenliang YANG Debin PEI Fuping jiN Ke LIU Xiaoming College of Earth Sciences Jilin UniversityChangchun Jilin 130061 Bureau of Land and Mineral Resources of jilin Province Changchun Jilin 130061 The State Key Laboratory of Continental Dynamics Northwest University Xi＇an Shaanxi 710069

Zircon U-Pb ages and geochemical data of volcanic rocks in the Suifenhe Formation in eastern Heilongjiang Province are reported, and their petrogenesis is discussed in this paper. The Suifenhe Formation mainly consists of basalt, andesite, and dacite. Zircon from andesite and dacite are euhedral in shape and show typical oscillatory zoning with high Th/U ratios （0.18-0.57）, implying its magmatic origin. Zircon U-Pb dating results by laser ablation inductively coupled plasma mass spectrometer （LA-ICP-MS） indicate that the ^206Pb/^238U ages of zircons from andesite range within 105- 106 Ma, yielding a weighted mean age of 105.5±0.8 Ma （n=14）, and that ^206pb/^238U ages of zircons from dacite are between 90-96 Ma, yielding a weighted mean age of 93.2±1.3 Ma （n =13）. The volcanic rocks from the Snifenhe Formation are subalkaline series and show a calc-alkaline evolutionary trend with SiO2 content of 47.69%-65.47%, MgO contents of 1.42%-6.80% （Mg^#= 45-53）, and Na2O/K2O ratios of 1.83-3.63. They are characterized by enrichment in large ion lithophile elements （LILE） and lightrare-earth elements （LREE）, depletion in heavy rare earth elements （HREE） and high field strength elements （HFSE）（e.g., Nb, Ta, Ti）, and low initial ^87Sr/^86Sr ratios （0.7041-0.7057） and positive εNd（t） ValUes （0.39-4.08）, implying that they could be derived from a depleted magma source. Taken together, these results suggest that the primary magma of the volcanic rocks might originate from partial melting of the mantle wedge metasomatized by fluids derived from subducted slab under a tectonic setting of active continental margin.

关键词： Suifenhe Formation volcanic rocks LA-ICP-MS zircon U-Pb dating geochemistry petrogenesis Cretaceous Heilongjiang Province

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Geochronology and petrogenesis of granitic rocks in Gangdese batholith, southern Tibet

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Science China Earth Sciences 2009年第7期52卷 1240-1261页

作者： ji weiqiang WU FuYuan LIU ChuanZhou CHUNG SunLin State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Graduate University of Chinese Academy of Sciences Beijing 100049China Department of Geoscience Taiwan UniversityTaipei 106China

Based on petrological and geochemical characteristics such as rock assemblage, petrogeochemistry, Sr-Nd isotope, zircon U-Pb age, and Hf isotope, we studied geochronological framework, magma types, source characters, and petrogenesis of different stages of magmatism of the granitic rocks from the Gangdese batholith in southern Tibet. The magmatic activities of the Gangdese batholith can be divided into three stages. The Mesozoic magmatism, induced by northern subduction of Neotethyan slab, was continuously developed, with two peak periods of Late Jurassic and Early Cretaceous. The Paleocene-Eocene magmatism was the most intensive, and resulted from a complex progress of Neotethyan oceanic slab, including subduction, rollback, and subsequent breakoff. And the Oligocene-Miocene magmatism was attributed to the convective removal of thickened lithosphere in an east-west extension setting after India-Asia collision. Isotopically, zircons from these granitic rocks are characterized by positive εHf(t) values, suggesting that the magmatic source of the Gangdese batholith might be an arc terrane, which was accreted to the southern margin of Asia during Late Paleozoic. Therefore, the chronological framework and Hf isotopic characteristics of the Gangdese batholith are distinct from the granitic rocks in adjacent areas, which can be served as a powerful tracer in studying source-to-sink relation of sediments during the uplift and erosion of Tibetan Plateau.

关键词： Tibet Gangdese batholith granitic rock geochronology petrogenesis

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Processes of initial collision and suturing between India and Asia

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Science China Earth Sciences 2017年第4期60卷 635-651页

作者： DING Lin Satybaev MAKSATBEK CAI FuLong WANG HouQi SONG PeiPing ji weiqiang XU Qiang ZHANG LiYun Qasim MUHAMMAD Baral UPENDRA Key Laboratory of Continental Collision and Plateau Uplift Institute of Tibetan Plateau Researchand Center for Excellence in Tibetan Plateau Earth SciencesChinese Academy of SciencesBeijing 100101China University of the Chinese Academy of Sciences Beijing 100049China Institute of Geology and Geophysics Chinese Academy of SciencesBeijing 100029China

The initial collision between Indian and Asian continents marked the starting point for transformation of land-sea thermal contrast,uplift of the Tibet-Himalaya orogen,and climate change in *** this paper,we review the published literatures from the past 30 years in order to draw consensus on the processes of initial collision and suturing that took place between the Indian and Asian *** a comparison of the different methods that have been used to constrain the initial timing of collision,we propose that the tectono-sedimentary response in the peripheral foreland basin provides the most sensitive index of this event,and that paleomagnetism presents independent evidence as an alternative,reliable,and quantitative research *** contrast to previous studies that have suggested collision between India and Asia started in Pakistan between ca.55 Ma and50 Ma and progressively closed eastwards,more recent researches have indicated that this major event first occurred in the center of the Yarlung Tsangpo suture zone(YTSZ) between ca.65 Ma and 63 Ma and then spreading both eastwards and *** continental collision is a complicated process,including the processes of deformation,sedimentation,metamorphism,and magmatism,different researchers have tended to define the nature of this event based on their own understanding,an intuitive bias that has meant that its initial timing has remained controversial for ***,we recommend the use of reconstructions of each geological event within the orogenic evolution sequence as this will allow interpretation of collision timing on the basis of multidisciplinary methods.

关键词： Timing of initial collision between the Indian and Asian continents Collision criteria Transform fault Subduction zone Magmatism Deformation

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Dynamic modeling of tectonic carbon processes:State of the art and conceptual workflow

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Science China Earth Sciences 2023年第3期66卷 456-471页

作者： Liang ZHAO Zhengtang GUO Huaiyu YUAN Xinxin WANG Hao SHEN jianfeng YANG Baolu SUN Ning TAN Hui ZHANG Yonggang LIU Yang LI jiamin WANG weiqiang ji Rixiang ZHU State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China ARC Centre of Excellence for Core to Crust Fluid Systems Department of Earth and Planetary SciencesMacquarie UniversityNew South Wales 2109Australia Laboratory for Climate and Ocean-Atmosphere Studies Department of Atmospheric and Oceanic SciencesSchool of PhysicsPeking UniversityBeijing 100871China

Plate tectonics plays a critical role in modulating atmospheric CO_(2)concentration on the geological timescale(≥106year).A growing consensus on tectonic and Earth’s CO_(2)history in the Cenozoic and deeper time provides solid restrictions and standards for testing tectonic carbon processes against global *** this,modeling the causal relationship between tectonic events and atmospheric CO_(2)levels remains a *** examine the current state of the global tectonic CO_(2)research and suggest a conceptual workflow for numerical experiments that integrates plate tectonics and deep carbon *** tectonic carbon cycle modeling should include at least four modules:(1)simulation of carbon-carrying processes,such as carbon ingassing and outgassing at the scale of minerals;(2)calculation of CO_(2)fluxes in tectonic settings like subduction,mantle plume,and plate rifting;(3)reconstruction of carbon cycling within the plates-scale tectonic scenario,particularly involving the processes of supercontinent convergence and dispersion;and(4)comparison with atmospheric CO_(2)history data and iterations,aiming to find the coincidental link between different tectonic carbon fluxes and climate *** to our analysis,the recent advancements in each of the four modules have paved the path for a more general *** envision that the large variety of carbon transportation parameters across more than ten orders of magnitude in both time and space is the primary technical hurdle in simulating tectonic carbon *** propose a boundary-condition-connected approach for simulating the global carbon cycle to realize carbon exchange between the solid earth and surface spheres.

关键词： Tectonic carbon cycling Tectonic CO_(2)modeling Boundary-condition-connected approach

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地球的挥发分循环与宜居环境演变

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岩石学报 2022年第5期38卷 1285-1301页

作者：纪伟强吴福元中国科学院地质与地球物理研究所岩石圈演化国家重点实验室北京100029 中国科学院大学地球与行星科学学院北京100049

地球宜居环境的形成和演变与挥发分循环密切相关。宜居性受地球表层系统中挥发分组成和变化的直接影响,但其本质上受控于地球深部系统的挥发分释放和循环过程。本文简要介绍了地球挥发分的起源、大气圈和海洋的形成与演化、深部挥发分... 详细信息

地球宜居环境的形成和演变与挥发分循环密切相关。宜居性受地球表层系统中挥发分组成和变化的直接影响,但其本质上受控于地球深部系统的挥发分释放和循环过程。本文简要介绍了地球挥发分的起源、大气圈和海洋的形成与演化、深部挥发分释放及对气候环境的影响、俯冲带挥发分循环等几个方面的研究概况。期望本文能使读者更好的理解本专辑稿件的内容,激发起同行对挥发分研究的兴趣,促进我国挥发分相关研究的发展。

关键词：挥发分火山去气俯冲大气圈碳循环气候演变

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