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Generation of andesite through partial melting of basaltic metasomatites in the mantle wedge:Insight from quantitative study of Andean andesites

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Geoscience Frontiers 2021年第3期12卷 636-668页

作者： Long Chen Yong-Fei Zheng Zheng Xu Zi-Fu Zhao CAS key laboratory of Crust-Mantle materials and environments School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China CAS Center for Excellence in Comparative Planetology Hefei 230026China State key laboratory of Isotope Geochemistry Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China

Continental crust in average exhibits a similar composition in both major and trace elements to andesites along active continental *** this reason,andesitic magmatism above oceanic subduction zones is considered to have played a key role in the generation of continental crust along convergent plate *** respect to the origin of andesites themselves,however,there is still a hot debate on how they have acquired their geochemcial *** debate is mainly centralized on the relative contributions of crustal contamination,magma differentiation and source mixing,which reaches an impasse in the past *** essential reason for this kind of debates is that these three mechanisms only can account for some of the geochemical observations for andesites,leading to insufficient discrimination among ***,the geochemical features of andesites are primarily controled from early to late by the composition of their source rocks in addition to partial melting and magma differentiation *** source mixing and partial melting processes in the early stage of andesite magmatism can account for the first-order geochemical features of andesites,there is no need to invoke the late processes of magma differentiation and crustal contamination for andesite *** is illustrated by quantitative forward modeling of the geochemical data for Quaternary andesites from the Andean arc in South America based on an integrated interpretation of these *** modeling has run with four steps from early to late:(1)dehydration of the subducting oceanic crust at forearc depths;(2)partial melting of the subducting terrigenous sediment and altered oceanic basalt at subarc depths to produce hydrous felsic melts;(3)the generation of basaltic metasomatites(e.g.,Si-excess pyroxenite)in the mantle wedge through reaction of the mantle wedge peridotite with large amounts of the hydrous felsic melts;(4)the production of andesitic melts by partial melting

关键词： Andean arc Andesite Magma differentiation Source mixing Crust-mantle interaction

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A newly Found Biotite Syenogranite in the Huangshaping Polymetallic Deposit, South China: Insights into Cu Mineralization

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Journal of Earth Science 2018年第3期29卷 537-555页

作者： Weicheng Jiang Huan Li Jinghua Wu Zhekai Zhou Hua Kong Jingya Cao Faculty of Earth Resources State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences key laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring Ministry of EducationSchool of Geosciences and Info-Physics Central South University CAS key laboratory of Crust-Mantle materials and environments School of Earth and Space Sciences University of Science and Technology of China

The W-Sn-Mo-Cu-Pb-Zn polymetallic mineralization in the Huangshaping Deposit is associated with different types of Jurassic granitic intrusions such as quartz porphyry, granophyre and granite porphyry. In this study, we carried out detailed mineralogical, petrological, geochemical, zircon U-Pb geochronological and Hf isotopic studies on a newly found, Cu-mineralization-related finegrained biotite syenogranite at Huangshaping. This syenogranite is mainly composed of quartz （40%）, K-feldspar （30%）, plagioclase （15%） and biotite （5%）, enriching in SiO2 （75.58 wt.%-76.02 wt.%）, K20 （5.24 wt.%-5.78 wt.%）, AI203 （12.23 wt.%-12.46 wt.%）, Rb （405 ppm-504 ppm）, U （18.5 ppm-40.7 ppm）, Th （47 ppm-52.3 ppm）, Nb （49.6 ppm-57.5 ppm）, and Cu （54 ppm-288 ppm） whereas depleting in P205 （0.01 wt.%）, TiO2 （0.05 wt.%-0.06 wt.%）, Ba （5 ppm-13.1 ppm）, Sr （6.8 ppm-23.9 ppm） and Eu （0.04 ppm-0.05 ppm）, with A1-type alkaline granite characteristics. Magmatic and hydrothermal zircons were separated from a Cu-mineralized syenogranite sample and yielded the ^206Pb/^238U concordant ages of 156.5±1.8 and 154.4±2.9 Ma, representing the intrusive age of the pluton and probable Cu-mineralization time at the Huangshaping Deposit, respectively. Zircon Hf isotopes suggest a crust-derived （partial melting of Paleoproterozoic basement） magma for the syenogranite, with some degree of crust-mantle interaction. We infer that the syenogranite is a transitional phase between the granophyre and the granite porphyry, not only contributed greatly to the Cu mineralization but also provided W-Sn polymetallic ore-forming metals for the Huangshaping Deposit.

关键词： zircon U-Pb dating Hf isotope A-type granite southern Hunan.

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Real-time restoration of rotational blurred image using gradient-loading

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Chinese Optics Letters 2008年第5期6卷 334-337页

作者：韩超阳李建勋陈萧朱振幅 Department of Automation Shanghai Jiao Tong University Optical Signature of Targets and environments key laboratory of National Defense Science and technology

The key to the restoration of rotational motion blurred image is how to restore the image under a low cost and to correct the irreversibility of the degradation function matrix. Based on the special qualities of degradation function matrix and precise deduction in space-domain, we present a new approach using gradient-loading for restoration of rotational blurred image. By easily adding a gradient operator, the irreversibility of the original matrix is corrected and can be applied for inverse filtering then. Gradient- loading is the optimized approach which combines the advantages of both the approaches using constrained least square filtering and traditional diagonal-loading. Compared with the approach using least square filtering, its peak signal-to-noise ratio （PSNR） is improved from 3.18 to 6.46 dB, while the computing time is reduced to 1/2 - 1/3. Experimental results demonstrate the effectiveness, noise-resistibility, robustness, and low complexity of this approach, which make it more suitable for real-time environment.

关键词： Chlorine compounds Constrained optimization Curve fitting Degradation Geodesy Least squares approximations Repair Restoration Signal to noise ratio

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Carbonated Big Mantle Wedge Extending to the NE Edge of the Stagnant Pacific Slab:Constraints from Late Mesozoic-Cenozoic Basalts from Far Eastern Russia

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Journal of Earth Science 2022年第1期33卷 121-132页

作者： Ronghua Cai Shan Xu Dmitri AIonov Jian Huang Sheng-Ao Liu Shuguang Li Jingao Liu State key laboratory of Geological Processes and Mineral Resources China University of GeosciencesBeijing 100083China Géosciences Montpellier Universitéde Montpellier34095 MontpellierFrance CAS key laboratory of Crust-Mantle materials and environments School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China

It has been suggested that the carbonated mantle reflected by Mg-Zn isotopic anomalies of Cenozoic intraplate basalts from East Asia coincides with the stagnant West Pacific slab in the mantle transition ***,the northern boundary of such carbonated domain beneath East Asia is *** Mesozoic-Cenozoic intraplate basalts are widespread in far eastern Russia and thus provide an opportunity to examine this *** we report major-trace element contents and Sr-NdMg-Zn isotopic compositions for 9 Late Mesozoic-Cenozoic basaltic samples from the Khanka Block and Sikhote-Alin accretionary *** are characterized by large variations in SiO_(2)contents(41 wt.%to 50 wt.%)and CaO/Al_(2)O_(3)(0.50 to 0.97),enrichments of large-ion lithophile elements(LILE),positive Nb-Ta anomalies and strongly negative K,Pb,Zr,Hf,Ti,Y anomalies in primitive mantle-normalized trace element spider ***,the rocks show good correlations of Ti/Ti^(*)with Hf/Hf^(*),La/Yb,Fe/Mn and trace element contents(e.g.,Nb).In addition,they have lighter Mg and heavier Zn isotope compositions than the BSE estimates,coupled with depleted Sr-Nd isotope *** elemental and isotopic characteristics cannot be explained by alteration,magma differentiation or diffusion,but are consistent with the partial melting of carbonated *** and large,the Late Mesozoic-Cenozoic basalts from far eastern Russia bear very similar geochemical characteristics as those Na-series Cenozoic basalts from eastern *** extended region of Mg-Zn isotopic anomalies is roughly coincident with the stagnant West Pacific slab beneath East Asia,and all of these alkali basalts can be generated from mantle sources hybridized by recycled Mg-carbonates from the Pacific slab stagnant in the mantle transition *** infer that(1)the carbonated big mantle wedge extends to the NE edge of the West Pacific slab and may have also appeared in the Late Mesozoic due to the effect of the Paleo-Pac

关键词： Mg-Zn isotopes deep carbon cycling far eastern Russia isotopes big mantle wedge

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Hydrothermal ore deposits in collisional orogens

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Science Bulletin 2019年第3期64卷 205-212页

作者： Yongfei Zheng Jingwen Mao Yanjing Chen Weidong Sun Pei Ni Xiaoyong Yang key laboratory of Crust-Mantle materials and environments Chinese Academy of Sciences School of Earth and Space Sciences University of Science and Technology of China key laboratory of Metallogeny and Mineral Assessment Ministry of Natural Rescources Institute of Mineral Resources Chinese Academy of Geological Sciences key laboratory of Orogen and Crustal Evolution Ministry of Education School of Earth and Space Sciences Peking University key laboratory of Marine Geology and Environment Center of Deep-Sea Research Institute of Oceanology Chinese Academy of Sciences State key laboratory for Mineral Deposits Research Institute of Geo-Fluids School of Earth Sciences and Engineering Nanjing University

Hydrothermal ore deposits at convergent plate boundaries represent extraordinary metal enrichment in the continental crust. They are generally associated with felsic magmatism in extensional settings at high thermal gradients. Although their formation is common during accretionary orogeny, more and more ore deposits have been discovered recently in the collisional orogens of China. Because collisional orogeny was operated in a compressional regime at low thermal gradients, it is not favorable for mobilization of ore-forming elements and thus for the production of hydrothermal ore deposits. Nevertheless, continental collision is generally preceded by oceanic subduction, which enables the preliminary enrichment of ore-forming elements in the mantle wedge due to chemical metasomatism by subducting slab-derived fluids. This gave rise to metal pre-enriched domains in the overriding lithosphere, which may be reactivated by extensional tectonism for hydrothermal mineralization either immediately during accretionary orogeny or at a later time during and after collisional orogeny. It is these tectonic processes that have resulted in the progressive enrichment of ore-forming elements through the geochemical differentiation of the subducting oceanic crust, the metasomatic mantle domains and the mafic juvenile crust, respectively, at different depths. Finally, the reactivation of metal pre-enriched domains by continental rifting in the orogenic lithosphere is the key to the metallogenesis of collisional orogens.

关键词： Ore deposits Hydrothermal fluid Accretionary orogen Collisional orogen Rifting orogen Tectonic reactivation

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From borophosphate to fluoroborophosphate:a rational design of fluorine-induced birefringence enhancement

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Science China Chemistry 2021年第9期64卷 1498-1503页

作者： Wenyao Zhang Zhizhong Zhang Wenqi Jin Ruonan Zhang Meng Cheng Zhihua Yang Shilie Pan CAS key laboratory of Functional materials and Devices for Special environments Xinjiang Technical Institute of Physics&ChemistryCASXinjiang Key Laboratory of Electronic Information Materials and DevicesUrumqi830011China Center of materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing100049China

The introduction of oxofluoride anion into anionic group assists to tune optical properties owing to the change of coordination,electronegativity,and according anionic ***,we proposed a rational design of new compounds by fluorine-driven structure and optical property evolution.A new borophosphate Ba_(2)BP_(3)O_(11)with the monoclinic space group P2_(1/c) has been synthesized in the sealed ***_(2)BP_(3)O_(11)exhibits a rare P-O-P bridge formation,which is the first example in alkaline-earth metal *** further substituting[BO_(4)]^(3-)with[BO_(3)F]^(4-),the first alkaline-earth metal/lead fluoroborophosphates M_(2)BP_(2)O_(8)F(M=Ba and Pb)with the same space group were *** the scissors effect of fluorine,in M_(2)BP_(2)O_(8)F(M=Ba and Pb),a BO_(3)F tetrahedron corner-sharing with three PO_(4)tetrahedra forms 1D chains along the b-axial direction,which are filled by MO_(n)(M=Ba/Pb,n=5,6,8)distorted *** first principles calculation shows that the borophosphate Ba_(2)BP_(3)O_(11)has a birefringence about 0.013@1,064 nm,while the fluoroborophosphates M_(2)BP_(2)O_(8)F(M=Ba and Pb)have the values of 0.035 and 0.043@1,064 nm,*** an apparent enhancement in birefringence is derived from synergies of the oxyfluoride and *** introduction of fluorine-containing heteroanionic groups provides a feasible strategy to design novel promising optical materials.

关键词： borophosphate fluoroborophosphates P-O-P bridges formation birefringence

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Developing the plate tectonics from oceanic subduction to continental collision

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Chinese Science Bulletin 2009年第15期54卷 2549-2555页

作者： ZHENG YongFei YE Kai ZHANG LiFei CAS key laboratory of Crust-Mantle materials and environments School of Earth and Space Sciences University of Science and Technology of China Hefei 230026 China State key laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China MOE key laboratory of Orogenic Belt and Crustal Evolution School of Earth and Space Sciences Peking University Beijing 100871. China

The studies of continental deep subduction and ultrahigh-pressure metamorphism have not only promoted the development of solid earth science in China, but also provided an excellent opportunity to advance the plate tectonics theory. In view of the nature of subducted crust, two types of subduction and collision have been respectively recognized in nature. On one hand, the crustal subduction occurs due to underflow of either oceanic crust (Pacific type) or continental crust (Alpine type). On the other hand, the continental collision proceeds by arc-continent collision (Himalaya-Tibet type) or continent-continent collision (Dabie-Sulu type). The key issues in the future study of continental dynamics are the chemical changes and differential exhumation in continental deep subduction zones, and the temporal-spatial transition from oceanic subduction to continental subduction.

关键词：板块构造理论板块俯冲发展中国家大陆碰撞大洋地壳大陆深俯冲带超高压变质作用固体地球科学

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evaluation of numerical ablation model for charring composites

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Science China(Technological Sciences) 2019年第8期62卷 1322-1330页

作者： LI Wei ZHANG Jun FANG GuoDong LI WeiJie LIANG Jun MENG SongHe Science and technology on Advanced Composites in Special environments key laboratory Harbin Institute of Technology Harbin 150001 China Institute of Advanced Structure technology Beijing Institute of Technology Beijing 100081 China

Charring composites are widely used in the thermal protection system(TPS) to consume the intense aerodynamic heating during vehicle reentry. The ablation and thermal responses for the charring composites can be studied by using a numerical ablation model, in which the surface ablation and volume ablation could be taken into account. The coupling interactions among temperature, gas motion and interior pressure producing the pyrolysis gas could make the computation more complicated. A multi-physics model is developed to simulate the thermal response coupled with volume ablation and surface ablation. After studying four typical ablation cases, the model is validated, and then the heat transfer mechanisms in ablation are investigated. It is found that the viscous dissipation energy by the motion of pyrolysis gas can be neglected in the simulation. Also, the flow of pyrolysis gas plays an important role in the temperature response, especially under high heat flux condition.

关键词： ablation charring composites numerical model coupling

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功能-要素-流视角下的乡村活力空间识别与评价——以中国杭州市临安区为例

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Journal of Geographical Sciences 2024年第6期34卷 1228-1250页

作者：张晶管晨悦章琳虞舟鲁叶成煊朱从谋李思楠王珂干牧野 Institute of Applied Remote Sensing and Information technology College of Environmental and Resource SciencesZhejiang UniversityHangzhou 310058China Zhejiang key Research laboratory of Agricultural Remote Sensing and Information technology Hangzhou 310058China Shandong(Linyi)Institute of Modern Agriculture Linyi 276000ShandongChina Huzhou Spatial Planning Preparation and Research Center Huzhou 313000ZhejiangChina Zhejiang Digital Governance space Planning and Design Co. Ltd.Hangzhou 310000China Department of Land Resources Management Zhejiang Gongshang UniversityHangzhou 310018China

Rural vitality is the life force expressed by a combination of endogenous dynamics and external influences. Exploring the complex relationship between rural functions, elements and flows could achieve sustainable rural development. This study constructed a theoretical framework guided by the four functions of production, living, ecology and culture with the support of mobile big data. Furthermore, the network centrality of villages was estimated to reflect the intensity of urban-rural social mobility ties. The results indicated marked spatial disparities in rural vitality, and the coupling of ecological-cultural vitality has a high degree of coherence. Four rural vitality grades were identified: high level(38, 14.08%), medium-high level(66, 24.44%), medium-low level(110, 40.74%) and low level(56, 20.74%), covering 270 administrative village units. The flow intensity of social linkage elements is consistent with rural vitality and the socioeconomic spillover effect of urban centers on neighboring villages was noticeable. Topographic complexity negatively affected the living function, mainly in the T1 and T2 terrain gradients;the rural ecological function was not fully correlated with urban adjacency, and proximity could lead to adverse effects such as urban sprawl and resource destruction. The application of this study is to explore the importance of “flow” by utilizing mobile big data to refine the evaluation unit to the village scale. Accelerating the construction of network coverage and information interconnection and promoting the elemental flow of people, transportation and information between urban and rural areas are important ways to enhance rural vitality.

关键词： rural vitality rural multifunction elements urban-rural flows mobile big data

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Phase transformation-induced Mg isotope fractionation in Mgmediated CaCO_(3)mineralization

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Nano Research 2023年第2期16卷 3597-3602页

作者： Yi-Ming Ju Fang Huang Xin Ding Li-Bo Mao Shu-Hong Yu Department of Chemistry Institute of Biomimetic Materials&ChemistryAnhui Engineering Laboratory of Biomimetic MaterialsDivision of Nanomaterials&ChemistryHefei National Research Center for Physical Sciences at the MicroscaleUniversity of Science and Technology of ChinaHefei 230026China CAS key laboratory of Crust-Mantle materials and environments School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China CAS Center for Excellence in Comparative Planetology University of Science and Technology of ChinaHefei 230026China

The biomineralization of CaCO_(3)often involves the transformation of amorphous precursors into crystalline phases,which is regulated by various proteins and inorganic ions such as Mg^(2+)*** the effects of Mg^(2+)ions on the polymorph and shape of the crystalline CaCO_(3)have been observed and studied,the interplay between Mg^(2+)ions and CaCO_(3)during the mineralization remains *** work focuses on the mechanism of Mg^(2+)ion-regulated mineralization of CaCO_(3).By tracing the Mg isotope fractionation,the different mineralization pathways of CaCO_(3)under different Mg^(2+)ion concentrations had been *** regulatory role of Mg^(2+)ions at the different stages of mineralization had been proposed through combining the fractionation data with the analyses of the CaCO_(3)polymorph and shape *** results provide a clear view of the Mg-mediated crystallization process of amorphous CaCO_(3),which can be used to finely control the phase of the crystalline products according to different needs.

关键词： mineralization calcium carbonate magnesium isotope fractionation

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