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The geomicrobiology of bauxite deposits

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Geoscience Frontiers 2010年第1期1卷 81-89页

作者： Xiluo Hao Kwunlun Leung Rucheng Wang weidong sun Yiliang Li Key Laboratory of Isotope Geochronology and Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of SciencesGuangzhou 510640 China Department of Earth Sciences The University of Hong Kong Pokfulam Road Hong Kong China Graduate School of the Chinese Academy of Sciences Beijing 100039 China School of Geological Sciences ＆ Engineering Nanjing University Nanjing 210093 China

Bauxite deposits are studied because of their economic value and because they play an important role in the study of paleoclimate and paleogeography of continents. They provide a rare record of the weathering and evolution of continental surfaces. Geomicrobiological analysis makes it possible to verify that microorganisms have played a critical role during the formation of bauxite with the possibility already intimated in previous studies. Ambient temperature, abundance of water, organic carbon and bioavailable iron and other metal substrates provide a suitable environment for microbes to inhabit. Thiobacillus, Leptospirilum, Thermophilic bacteria and Heterotrophs have been shown to be able to oxidize ferrous iron and to reduce sulfate-generating sulfuric acid, which can accelerate the weathering of aluminosilicates and precipitation of iron oxyhydroxides. Microorganisms referred to the genus Bacillus can mediate the release of alkaline metals. Although the dissimilatory iron-reducing and sulfate-reducing bacteria in bauxites have not yet been identified, some recorded authigenic carbonates and ＂bacteriopyrites＂ that appear to be unique in morphology and grain size might record microbial activity. Typical bauxite minerals such as gibbsite, kaolinite, covellite, galena, pyrite, zircon, calcium plagioclase, orthoclase, and albite have been investigated as part of an analysis of microbial mediation. The paleoecology of such bauxitic microorganisms inhabiting continental （sub） surfaces, revealed through geomicrobiological analysis, will add a further dimension to paleoclimatic and paleoenvironmental studies.

关键词： Geomicrobiology Bauxite Microbial activity Microbial-mediated release of elements Biomineralization

High-precision timing of the Quaternary standard samples with thermal ionization mass spectrometry (TIMS) U-series method

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Chinese Science Bulletin 1998年第4期43卷 333-336页

作者： Peng Zicheng Wang Zhaorong sun weidong Ma Zhibang Xia Ming Zhang Chenhui Chen Wenji Zhang Zhonglu An Zhisheng Univ Sci & Technol China Dept Earth & Space Sci Hefei 230026 Peoples R China Chinese Acad Sci Inst Geol Beijing 100029 Peoples R China State Seismol Bur Inst Geol Beijing 100029 Peoples R China State Key Lab Loess & Quaternary Geol Xian 710054 Peoples R China

Two national stalagmite standard （GBW04412, GBW04413） and one international coral standard （RKM4） have been determined by using thermal ionization mass spectrometry （TIMS） method. The values of （ 234 U/ 238 U） act , （ 230 Th/ 234 U） act and age are all consistent in error range with the standard values obtained by using α spectrometry.

关键词： thermal ionization mass spectrometry (TIMS) U_series method standard samples stalagmite and coral age determination.

Toward Closer China-Pakistan Community With Shared Future

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China News Release 2023年第10期 8-12页

作者： sun weidong minister of foreign affairs

A decade ago,Chinese President Xi Jinping successively put forward the vision of a community with a shared future for mankind,the Belt and Road Initiative and the guiding principles for neighborhood diplomacy featuring amity,sincerity,mutual benefit,and ***,a reliable ally of China,eagerly *** 2013,the China-Pakistan Economic Corridor(CPEC)was launched as an important pioneering project of the Belt and Road *** Xi attaches high importance to the growth of China-Pakistan relations and the construction of the CPEC.

关键词： Pakistan mutual neighborhood

New discrimination diagrams for basalts based on big data research

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Big Earth Data 2019年第1期3卷 45-55页

作者： Qi Zhang weidong sun Yong Zhao Fanglin Yuan Shoutao Jiao Wanfeng Chen Institute of Geology and Geophysics Chinese Academy of ScienceBeijing 100029China Center of Deep Sea Research Institute of OceanographyChinese Academy of SciencesQingdaoChina Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and TechnologyQingdaoChina CAS Center for Excellence in Tibetan Plateau Earth Sciences Chinese Academy of SciencesBeijingChina State Key Laboratory of Continental Dynamics Department of GeologyNorthwest UniversityXi’anChina School of Earth Sciences and Engineering SUN YAT-SEN UniversityGuangzhouChina Key Laboratory of Mineral Resources in Western China(Gansu Province) School of Earth SciencesLanzhou UniversityLanzhouChina

In recent days,discrimination diagrams have been widely used for tracing the tectonic settings and origins of basalts from orogenic ***,conventional discrimination diagrams are not accurate ***,we reported six new discrimination diagrams obtained from the global database using data mining *** most individual diagrams,island arc basalt can be nearly 100%was identified,whereas ocean island basalt and midocean ridge basalt can be discriminated from each other with less than 10%of overlap,under a confidence coefficient of 85%.Using the six new discrimination diagrams together,basalts of different origins can be efficiently identified.

关键词： Big data discrimination diagram tectonic settings SVM GEOROC

The formation of deep sea plastic biotas

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Science Bulletin 2022年第7期67卷 674-675页

作者： Xiaohua Li weidong sun Center of Deep Sea Research Center of Ocean Mega ScienceInstitute of OceanologyChinese Academy of SciencesQingdao 266071China Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and TechnologyQingdao 266237China University of Chinese Academy of Sciences Beijing 100049China

Deep sea plastic biotas are formed by floating plastics that sank after *** with nutrition and high biodiversity attract deep sea creatures and act as stepping-stone for biological *** are cheap,light,water proof,sturdy and durable,with high *** is easy to shape and resistant to chemical cor***,plastics are widely used in the modern society,representing a major progress in human *** production of plastics has increased considerably over the last few decades from 1.7 million metric tons per year in the 1950s to 370 million metric tons per year in 2019[1].As a result,plastic wastes also increase quickly,e.g.,by~10%every year in the last *** 6.3 billion metric tons of plastic wastes were generated between 1950 and 2015[2].Given that its degradation takes hundreds of years,plastic is even proposed as the No.1 environmental *** than tens of thousands metric tons of plastics are dumped into the ocean every year[3].Fishing thread,microplastics and other plastics are indeed an increasing threat to ocean lives:ingestions and entanglements by the marine life[4].Nevertheless,the impact of such large amount of plastic garbage on ocean environment remains to be fully explored.

关键词： plastics hundreds fouling

Neoproterozoic Diamictite of the Luoquan Formation from the North China Block and Their Implications

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Journal of Earth Science 2023年第4期34卷 1128-1139页

作者： Peishan Sui weidong sun Nan Han Lei Wang Shiwen Xie Zihang Huang Xiaohong Wang Hongmei Gong Jin Liu Jinyan Lin Yuanyuan Xiao CAS Key Laboratory of Marine Geology and Environment Institute of OceanologyChinese Academy of SciencesQingdao 266071China Laboratory for Marine Geology Qingdao National Laboratory for Marine Science and TechnologyQingdao 266061China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Center for Ocean Mega-Science Chinese Academy of SciencesQingdao 266071China Center of Deep-Sea Research Institute of OceanologyChinese Academy of SciencesQingdao 266071China Changqing Oilfield Exploration and Development Research Institute Xi'an 710018China Yanchang Oilfield Exploration and Development Technology Research Center Xi'an 716001China Beijing SHRIMP Center Institute of GeologyChinese Academy of Geological SciencesBeijing 100037China Public Technology Service Center Institute of OceanologyChinese Academy of SciencesQingdao 266071China Department of Geology Northwest UniversityXi'an 710069China

Glacial diamictite may provide important information on paleoenvironment and average composition of the upper continental crust(UCC).In this study,we report sedimentary facies,petrological and geochemical characteristics of Neoproterozoic diamictite from a profile of the Luoquan Formation on the southern margin of the North China Block(NCB).Upwards the sampling profile,lithostratigraphic strata vary from massive diamictite with poorly sorted carbonate gravels to laminated diamictite with small gravels of terrestrial detrital *** the profile,CaO-MgO-LOI-Sr values decrease with the increase of SiO_(2)-Al2O_(3)-K2O *** these petrological and geochemical variations indicate a change from lodgement till deposition in the proximal of ice sheet to ice-rafting deposition in glacial-marine environment with less dolomite to supply their *** with previous studies on diamictite from other outcrops on the NCB,the deposition of Luoquan diamictite reflects that the glaciation on the NCB vanished and the ice-rafting effect weakened with glacial transgression *** addition,significant co-variations of various elements with La and Al2O_(3)confirm the significant conservation of most analyzed elements during the sedimentary processes to produce diamictite.

关键词： diamictite North China Craton paleoenvironment the Luoquan Formation Neopro-terozoic sedimentation.

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“岩浆引擎”与板块运动驱动力

科学通报 2019年第28期64卷 2988-3006页

作者：孙卫东中国科学院海洋研究所深海研究中心中国科学院海洋大科学中心青岛海洋科学与技术试点国家实验室海洋矿产资源评价与探测技术功能实验室中国科学院大学海洋学院

从能量的角度看,地球内部的热是驱动板块运动的主要能量_热能要转化为动能需要集中有序释放.在地球上,热能最主要的集中有序释放发生在洋中脊岩浆作用过程中.根据“岩浆引擎”模型,在洋中脊不断形成新洋壳,新洋壳轻而薄,老洋売厚而重,... 详细信息

从能量的角度看,地球内部的热是驱动板块运动的主要能量_热能要转化为动能需要集中有序释放.在地球上,热能最主要的集中有序释放发生在洋中脊岩浆作用过程中.根据“岩浆引擎”模型,在洋中脊不断形成新洋壳,新洋壳轻而薄,老洋売厚而重,致使整个板片斜置于软流圈上,产生下滑力,导致洋中脊不断扩张,形成新洋壳并推动俯冲带老洋壳的消亡,从而驱动板块运动.地幔柱岩浆活动是“岩浆引擎”的另一种表现形式.大的地幔柱头会引起上覆岩石圈受热,与大量上涌的岩浆共同作用,在其中心部位产生千米级的隆升,从而导致地壳局部大幅度的倾斜,产生向外的下滑力.当下滑力足够大时,岩石圈拉张破裂,向两边推挤扩张,同时远端洋壳在薄弱地带挤压破裂,产生板块俯冲.这是板块运动最初起始和“岩浆引擎”的点火器.在板块构造体制下,板块俯冲起始有两种主要形式,自发俯冲和诱导俯冲.自发俯冲起始往往发生在老洋盆,通常产生双向俯冲;诱导俯冲起始则往往发生于年轻洋盆,通常产生单向俯冲.新特提斯洋的多次单向俯冲闭合是诱导俯冲起始所致.“岩浆引擎”主要作用于与洋中脊和地幔柱相关的板块.其他板块构造运动的能量主要来自于板块相互作用.

关键词：板块构造板块运动驱动力岩浆引擎板块滑移力俯冲起始

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Open Journal of Applied Sciences 2013年第1期3卷 41-46页

作者： Xiawei Chen Jing Yu weidong sun Department of Electronic Engineering Tsinghua University Beijing China

To solve the problem of the spatial correlation for adjacent areas in traditional spectral unmixing methods, we propose an area-correlated spectral unmixing method based on Bayesian nonnegative matrix factorization. In the proposed me-thod, the spatial correlation property between two adjacent areas is expressed by a priori probability density function, and the endmembers extracted from one of the adjacent areas are used to estimate the priori probability density func-tions of the endmembers in the current area, which works as a type of constraint in the iterative spectral unmixing process. Experimental results demonstrate the effectivity and efficiency of the proposed method both for synthetic and real hyperspectral images, and it can provide a useful tool for spatial correlation and comparation analysis between ad-jacent or similar areas.

关键词： Hyperspectral Image Spectral Unmixing Area-Correlation Bayesian Nonnegative Matrix Factorization

The formation of porphyry copper deposits

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Acta Geochimica 2017年第1期36卷 9-15页

作者： weidong sun Jin-tuan Wang Li-peng Zhang Chan-chan Zhang He Li Ming-xing Ling Xing Ding Cong-ying Li Hua-ying Liang CAS Key Laboratory of Mineralogy and Metallogeny Guangzhou Institute of GeochemistryThe Chinese Academy of SciencesGuangzhou 510640China CAS Center for Excellence in Tibetan Plateau Earth Sciences The Chinese Academy of SciencesBeijing 100101China State Key Laboratory of Isotope Geochemistry Guangzhou Institute of GeochemistryThe Chinese Academy of SciencesGuangzhou 510640China Center of Deep Sea Research Institute of OceanologyChinese Academy of SciencesQingdao 266071China

Copper is a moderately incompatible chalcophile *** behavior is strongly controlled by *** speciation of sulfur is controlled by oxygen ***,porphyry Cu deposits are usually oxidized(with oxygen fugacities > AFMQ +2)(Mungall 2002;sun et al.2015).The problem is that while most of the magmas at convergent margins are highly oxidized,porphyry Cu deposits are very rare,suggesting that high oxygen fugacity alone is not *** melting of mantle peridotite even at very high oxygen fugacities forms arc magmas with initial Cu contents too low to form porphyry Cu deposits directly(Lee et al.2012;Wilkinson 2013).Here we show that partial melting of subducted young oceanic slabs at high oxygen fugacity(>AFMQ +2) may form magmas with initial Cu contents up to >500 ppm,favorable for porphyry ***-enrichment of Cu through sulfide saturation and accumulation is not necessarily beneficial to porphyry Cu *** contrast,remelting of porphyritic hydrothermal sulfide associated with iron oxides may have major contributions to porphyry *** overriding continental crust reduces the "leakage" of hydrothermal fluids,thereby promoting porphyry ***,it is also more difficult for ore forming fluids to penetrate the thick continental crust to reach the depths of 2—4 km where porphyry deposits form.

关键词： Porphyry Cu deposit Oxygen fugacity Slabmelting Sulfide Sulfate Solubility