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Plate subduction, oxygen fugacity, and mineralization

Journal of Oceanology and Limnology 2020年第1期38卷 64-74页

作者： LIU He LIAO Renqiang ZHANG Lipeng LI Congying sun weidong Key Laboratory of Marine Geology and Environment Center of Deep-Sea ResearchInstitute of OceanologyChinese Academy of SciencesQingdao 266071China Laboratory for Marine Mineral Resources Laboratory for Marine Biology and BiotechnologyPilot National Laboratory for Marine Science and TechnologyQingdao 266071China Center for Ocean Mega-Science Chinese Academy of SciencesQingdao 266071China University of Chinese Academy of Sciences Beijing 100049China

Plate subduction is the largest natural factory that processes elements,which controls recycling and mineralization of a variety of *** are three major ore deposit belts in the world:the circumPacific,the centralAsian,and the Tethys *** the three belts are closely associated with plate subductions,the mechanism remains *** approached this problem from systematic studies on the behaviours of elements during geologic *** contribution summaries the recent progress of our research *** results suggest that porphyry Cu deposits form through partial melting of subducted young oceanic crust under oxygen fugacities higher than AFMQ^+1.5,which is promoted after the elevation of atmospheric oxygen at ca.550 *** deposits are associated with reducing magmatic rocks formed as a consequence of slab *** Neo-Tethys tectonic regime hosts more than 60%of the world's total Sn *** is due to the reducing environment formed during the subduction of organic rich *** the same reason,porphyry Cu deposits formed in the late stages during the closure of the Neo-Tethys *** deposits are also controlled by slab rollback,but is not so sensitive to oxygen *** related W/Sn deposits are mostly accompanied by abundant accessory fluorites due to the breakdown of phengite and *** of phengite is also significant for hard rock lithium deposits,whereas orogenic belt resulted from plate subduction promote the formation of Li brine *** red bed basins near the Nanling region are favorable for Li *** Mo and Re are enriched in the oxidationreduction cycle during surface processes,and may get further enriched once Mo-,Re-enriched sediments are subducted and involved in *** plate subduction,Mo and Re fractionate from each *** is mainly hosted in porphyry Mo deposits and to a less extent,porphyry Cu-Mo deposits,whereas Re is predominantly hosted in

关键词： plate subduction oxygen fugacity ore deposits geochemical behaviors subduction factory

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Adaptive data-driven parallelization of multi-view video coding on multi-core processor

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Science in China(Series F) 2009年第2期52卷 195-205页

作者： PANG Yi HU weidong sun LiFeng YANG ShiQiang Department of Computer Science and Technology Tsinghua University Beijing 100084 China

Multi-view video coding （MVC） comprises rich 3D information and is widely used in new visual media, such as 3DTV and free viewpoint TV （FTV）. However, even with mainstream computer manufacturers migrating to multi-core processors, the huge computational requirement of MVC currently prohibits its wide use in consumer markets. In this paper, we demonstrate the design and implementation of the first parallel MVC system on Cell Broadband Engine^TM processor which is a state-of-the-art multi-core processor. We propose a task-dispatching algorithm which is adaptive data-driven on the frame level for MVC, and implement a parallel multi-view video decoder with modified H.264/AVC codec on real machine. This approach provides scalable speedup （up to 16 times on sixteen cores） through proper local store management, utilization of code locality and SIMD improvement. Decoding speed, speedup and utilization rate of cores are expressed in experimental results.

关键词： adaptive data-driven multi-view video coding Cell Broadband Engine^TM Processor parallelization

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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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Spectral study on feldspar thermoluminescence process

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Science China(Physics,Mechanics & Astronomy) 2008年第3期51卷 225-231页

作者： GONG GeLian LIU ShunSheng XIA Bin sun weidong HUANG BaoLin Guangzhou Institute of Geochemistry Chinese Academy of SciencesGuangzhou 510640China Graduate University of the Chinese Academy of Sciences Beijing 100864China

Feldspar thermoluminescence fading phenomena were investigated here by using newly-constructed thermoluminescence spectrometer on the basis of charge-cou-pled detector,and thereafter the discussion and explanation on feldspar TL fading mechanism were presented. The experimental results show that the fading rate of feldspar TL depends on both wavelength and stimulated temperature,and normally the feldspar TL in every region of wavelength and temperature shows different traits,namely the low temperature TL (170℃-190℃) fading at the rate of logarith-mic function and furthermore the TL of different wavelengths fading at approxi-mately the same rate on the condition of 160℃ preheating. While the medium and high temperature TLs (290℃-400℃) do not show much thermal fading,their fading rate at room temperature invariably correlates well with their wavelength,namely the longer TL wavelength,the slower TL fading rate. The thermal instability of traps and the quantum-mechanical tunneling effects can explain the above fading phe-nomena respectively. It is recognized that feldspar TL fading depends on its wave-length,and furthermore new aspects of the solid thermoluminescence process can be displayed by the combination of three-dimensional TL spectral analysis and thermal fading or anomalous fading of TL for feldspar.

关键词： feldspar thermoluminescence spectral anomalous fading thermoluminescence process

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The influence of silica on reaction rates and molecular hydrogen(H_(2))generation during olivine hydrothermal alteration

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Science China Earth Sciences 2024年第1期67卷 222-233页

作者： Ruifang HUANG weidong sun Xing DING Yusheng ZHAO Yibing LI Xiuqi SHANG CAS Key Laboratory of Ocean and Marginal Sea Geology South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China SUSTech Academy for Advanced Interdisciplinary Studies Southern University of Science and TechnologyShenzhen 518055China Center of Deep Sea Research Institute of OceanologyChinese Academy of SciencesQingdao 266071China State Key Laboratory of Isotope Geochemistry Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China Institue of Geology Chinese Academy of Geological SciencesBeijing 100037China

Hydrothermal alteration of olivine greatly influences geodynamics and the recycling of volatiles(such as water and carbon)in subduction *** is an important component of geological fluids,and its influence on the hydrothermal alteration of olivine remains poorly *** this study,we performed experiments at 300–515℃ and 3.0 kbar(1 bar=10^(5)Pa)by reacting well homogenized mixtures of olivine and silica powders with saline solutions(0.5 mol L^(−1)NaCl).Silica greatly influences the reaction pathways,reaction rates,and molecular hydrogen(H_(2))formation during olivine hydrothermal *** experiments at 300℃ and 3.0 kbar with mixtures of olivine and 10 wt%silica,olivine was replaced by serpentine and *** proportions of serpentine and talc were determined according to standard curves based on infrared spectroscopy *** 6.5%serpentine and 12%talc were produced after an experimental duration of 7 days,which had no change after a longer period(14 days).Compared to the kinetics in silica-free systems,the rates of olivine hydrothermal alteration in experiments with 10 wt%silica are much *** overall reaction is:4.5Forsterite+5.5SiO_(2),aq+4H_(2)O=Serpentine+*** the addition of more silica(20 wt%and 40 wt%),olivine was transformed into *** rates of reaction were much faster,e.g.,for experiments with olivine and 20 wt%silica,43%of talc was produced after 14 days,which increased to 77%for experiments with 40 wt%silica over the same *** overall reaction is:3Forsterite+5SiO_(2),aq+2H_(2)O=*** experiments at 400–505℃ and 3.0 kbar,the promoting effect of silica on olivine hydrothermal alteration was also observed,which is closely associated with a decrease in Gibbs free energies of olivine hydrothermal *** 300℃ and 3.0 kbar,silica decreased H_(2)formed during olivine hydrothermal alteration by around an order of magnitude,resulting in an increase in oxygen *** on measured H_(2),we calibrated ox

关键词： Olivine hydrothermal alteration Silica Serpentinization Hydrogen Serpentine

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SHRIMP zircon U-Pb dating from K-bentonite in the top of Ordovician of Wangjiawan Section,Yichang,Hubei,China

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Science China Earth Sciences 2008年第4期51卷 493-498页

作者： HU YanHua ZHOU JiBin SONG Biao LI Wei sun weidong Key Laboratory of Isotope Geochronology and Geochemistry Guangzhou Institute of GeochemistryChinese Academy of Sci-encesGuangzhou 510640China Beijing SHRIMP Center Institute of GeologyChinese Academy of Geological SciencesBeijing 100037China School of Earth and Space Science University of Science and Technology of ChinaHefei 230026China Graduate University of the Chinese Academy of Sciences Beijing 100049China

The Global boundary Stratotype Section and Point (GSSP) for the base of the Hirnantian Stage (the latest stage of the Ordovician System) is defined at a point 0.39m below the base of the Kuanyinchiao Bed in the Wangjiawan North Section, which is the upper most "golden spike" of the Ordovician. However, this "golden spike" is lack of reliable geochronology data. This article gives a sensitive high resolution ion microprobe (SHRIMPII) zircon U-Pb dating for a K-bentonite sample from the Kuany-inchiao Bed in the Wangjiawan North Section. The age of the K-bentonite sample is 443.2±1.6 Ma, that is to say, the isotopic age of the uppermost of Hirnantian Stage, the point of Ordovician-Silurian boundary, should be near to, but slightly younger than 443.2±1.6 Ma. This age is identical to the Ordovi-cian-Silurian boundary age 443.7±1.5 Ma as declared by International Commission on Stratigraphy (ICS). So, this research provides some good geochronlogical data for the Hirnantian Stage and the Ordovician-Silurian boundary as well as the global correlation.

关键词： Hirnantian zircon SHRIMP bentonite Ordovician-Silurian boundary

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Testing the mantle plume hypothesis： an IODP effort to drill into the Kamchatka-Okhotsk Sea basement

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Science Bulletin 2017年第21期62卷 1464-1472页

作者： Yaoling Niu Xuefa Shi Tiegang Li Shiguo Wu weidong sun Rixiang Zhu Laboratory for Marine Geology Qingdao National Laboratory for Marine Science and TechnologyQingdao 266061China Department of Earth Sciences Durham UniversityDurham DH1 3LEUK lnstitute of Oceanology Chinese Acadermy of SciencesQingdao 266071.China First Institute of Oceanography State Oceanic AdministrationQingdao 266061China Institute of Deep-sea Science and Engineering Chinese Acadery of SciencesSanya 572000China Institute of Geology 8 Geophysics Chinese Academy of SciencesBeijing 100029China

The great mantle plume debate(GPD) has been going on for ~15 years(Foulger and Natland, 2003;Anderson, 2004; Niu, 2005; Davies, 2005; Foulger, 2005; Campbell, 2005; Campbell and Davies, 2006),centered on whether mantle plumes exist as a result of Earth's cooling or whether their existence is purely required for convenience in explaining certain Earth phenomena(Niu, 2005). Despite the mounting evidence that many of the so-called plumes may be localized melting anomalies, the debate is likely to continue. We recognize that the slow progress of the debate results from communication *** debaters may not truly appreciate(1) what the mantle plume hypothesis actually is, and(2) none of the petrological, geochemical and geophysical methods widely used can actually provide smoking-gun evidence for or against mantle plume hypothesis. In this short paper, we clarify these issues, and elaborate a geologically effective approach to test the hypothesis. According to the mantle plume hypothesis, a thermal mantle plume must originate from the thermal boundary layer at the core-mantle boundary(CMB), and a large mantle plume head is required to carry the material from the deep mantle to the surface. The plume head product in ocean basins is the oceanic plateau, which is a lithospheric terrane that is large(1000's km across), thick(>200 km), shallow(2–4 km high above the surrounding seafloors), buoyant(~1% less dense than the surrounding lithosphere), and thus must be preserved in the surface geology(Niu et al., 2003). The Hawaiian volcanism has been considered as the surface expression of a type mantle plume, but it does not seem to have a(known) plume head product. If this is true, the Hawaiian mantle plume in particular and the mantle plume hypothesis in general must be questioned. Therefore, whether there is an oceanic plateau-like product for the Hawaiian volcanism is key to testing the mantle plume hypothesis, and the Kamchatka-Okhotsk Sea basement is the best cand

关键词： Mantle plume debate Geologically testing plume hypothesis Drilling into Kamchatka-Okhotsk Sea basement

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Reworking of the Juvenile Crust in the Late Mesozoic in North Qinling,Central China

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Journal of Earth Science 2022年第3期33卷 623-641页

作者： Ying-Yu Xue Haiyang Liu Zhiyi Wang weidong sun Fukun Chen Center of Deep Sea Research Institute of OceanologyChinese Academy of SciencesQingdao 266071China Laboratory for Marine Mineral Resources Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China Center for Ocean Mega-Science Chinese Academy of SciencesQingdao 266071China University of Chinese Academy of Sciences Beijing 100049China

The Qinling Orogen resulted from the collision between the North and South China blocks in the *** granitoids,ranging from the Triassic to the Cretaceous,are widely distributed in this orogen,and they provide excellent clues for understanding the crustal evolution and geodynamic evolution of the orogenic *** Triassic belt is mostly located in the South Qinling,whereas the Cretaceous belt is located mostly in the North *** Taibai complex pluton is located at the conjunction of the two *** we present a data set comprising zircon U-Pb dating and elemental and Sr-Nd isotopic geochemistry for Late Mesozoic granite and microgranular enclaves(MME)exposed in the Taibai complex *** granite and MME yield concordant U-Pb zircon ages of 124 to 118 Ma,indicating that they were products of roughly simultaneous magmatism in the Late *** granite rocks are high-K,calc-alkaline,and weakly peraluminous in compositions,and they are characterized by enrichment in large ion lithophile elements(e.g.,Rb,Ba),depletion in high field strength elements(e.g.,Nb,Ta,Zr,Ti),and variable Sr/Y ratios of 7.64 to *** MgO,Cr,and Ni contents imply that the magma(s)were essentially *** the granite and the MME show relative depletion in Sr-Nd isotopic composition(initial ^(87)Sr/^(86)Sr of 0.7044 to 0.7067,initialε_(Nd) values of-3.4 to-2.6),suggesting that the magma(s)originated from juvenile crustal *** Sr-Nd isotopic characteristics are significantly different from those of other Late Mesozoic granitoids exposed elsewhere in the Qinling orogenic belt,which formed from much older and enriched sources and with negligible contributions from mantle or juvenile *** propose a reworking event of the juvenile crust during the Late Mesozoic that was triggered by the tectonic extension and subsequent asthenospheric upwelling that occurred in eastern China.

关键词： Qinling Orogen Mesozoic granite crustal reworking Nd isotope geochemistry

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Microbial life under Martian permafrost layer

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The Innovation 2024年第6期5卷 13-14页

作者： Xiuqi Shang Ruifang Huang weidong sun Center of Deep Sea Research Key Laboratory of Ocean Observation and ForecastingInstitute of OceanologyChinese Academy of SciencesQingdao 266071China Key Laboratory of Tropical Oceanography South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China Laboratory for Marine Mineral Resources Ocean Sciences and Interdisciplinary FrontiersLaoshan LaboratoryQingdao 266237China University of Chinese Academy of Sciences Beijing 100049China

Aromatic compounds have been detected by the Curiosity and Perseverance rovers,suggesting their familiar presence on theMartian surface.1 These organic compounds were previously attributed to water-rock ***,according to our knowledge,no experimental or theoretical evidence substantiates the formation of aromatic compounds purely throughwater-rock reactions in natural conditions.

关键词： conditions surface purely

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Nd isotopic disequilibrium between minerals and Rb-Sr age of the secondary phengite in eclogite from the Yangkou area,Qingdao,eastern China

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Chinese Science Bulletin 2001年第3期46卷 252-255页

作者： LI Shuguang sun weidong ZHANG Zongqing LI Qiuli Chemical Geodynamics Laboratory Department of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China

There are two generations of white micas in retrograded coesite-bearing eclogite from the Yangkou area near Qingdao, eastern China. The secondary phengite developed along the folliations in eclogite is the majority of the white micas. Nd and Sr isotopic disequilibriums between garnet and retrograded omphacite as well as secondary phengite have been observed. Consequently, the Rb-Sr ages ((193±4) Ma-(195±4) Ma) given by the tie lines of the secondary phengite + garnet or whole rock may predate the formation time of the phengite. The Rb-Sr age of (183±4) Ma given by the secondary phengite + retrograde omphacite is much closer to the formation time of the phengite indicating the retrograde age of eclogite instead of a cooling age of eclogite at 500℃.

关键词： eclogite Nd isotopic disequilibrium Rb-Sr dating Su-Lu UHPM belt.

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