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Formation and Evolution of a Paleosol across the Lower Silurian-Lower Permian Boundary in Zunyi District,Northern Guizhou,China and Its Paleoenvironment and Paleoclimate Implications

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Acta Geologica Sinica(English Edition) 2015年第6期89卷 2012-2029页

作者： XIONG Xiaohui XIAO Jiafei HU Ruizhong wang Jian wang Yi wang xinsong DENG Qi State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of Sciences Chengdu Institute of Geology and Mineral Resources Key Laboratory for Sedimentary Basin and Oil and Gas Resources Ministry of Land Resources Chinese Academy of Geological Sciences Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences

This paper presents a set of bulk geochemical and mineralogical data from a paleoweathering profile located in Zunyi District, Northern Guizhou, China. It was formed at the top of the Hanjiadian Formation of the Lower Silurian. A truncated, argillic, gleyed, kryptic paleospodosol is recognized in the paleoweathering profile. Ratios of immobile elements（Ti/Zr, Ti/Al） and their binary（e.g., Nb vs. Zr/TiO_2 and Th/Sc vs. Zr/Sc）, triangular diagrams（La-Th-Sc, Th-ScZr/10, Zr-Cr-Ga） reflect that the Gaojiayan paleosol is the product of in-situ weathering of gray-green silty mudstone of the underlying Hanjiadian Formation. Mass balance calculations indicate K enrichment and Na enrichment in the upper and lower portions of paleosol, respectively. These findings both are the results of transgression, which brings substantial concentrations of such elements as K, Na, and Sr. In particular, K enrichment is achieved by the illitization of kaolinite. The biological processes of terrestrial vascular plants also enhance K concentration, especially at the top of the paleosol. Na enrichment is a consequence of albitization and/or adsorption by clay minerals through cation exchange. The mass distributions and relative mass changes of rare earth elements（REEs） in the studied profile display characteristics of vertical zonation. Three peaks in total REEs content are observed, indicating two paleoclimatic or paleoenvironmental changes. Mineralogical characteristics indicate that the paleoclimate changed first from warm and humid to cold and dry and later, to dry and lightly warmer. The corresponding soil environment varies from weakly acidic to strongly alkaline and later, to weakly acidic. Mass translocation characteristics of REEs and several transition metals suggest that the Gaojiayan paleosol may have undergone top erosion.

关键词： paleosol paleoclimate paleoenvironment Lower Silurian-Lower Permian NorthernGuizhou

Copper partitioning between granitic silicate melt and coexisting aqueous fluid at 850°C and 100 MPa

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Acta Geochimica 2016年第4期35卷 381-390页

作者： Shuilong wang Hui Li Linbo Shang Xianwu Bi xinsong wang Wenlin Fan State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China Geophysical Exploration Institute of Heilongjiang Province Harbin 150036China University of Chinese Academy of Sciences Beijing 100039China

Experiments on the partitioning of Cu between different granitic silicate melts and the respective coexisting aqueous fluids have been performed under conditions of 850 ℃, 100 MPa and oxygen fugacity （fO2） buffered at approaching Ni-NiO （NNO）. Partition coefficients of Cu （Dcu = Cfluid/Cmelt） were varied with different alumina/alkali mole ratios [Al2O3/（Na2O ＋ K2O）, abbreviated as Al/ Alk], Na/K mole ratios, and SiO2 mole contents. The DCu increased from 1.28 ± 0.01 to 22.18 ±0.22 with the increase of Al/Alk mole ratios （ranging from 0.64 to 1.20） and Na/K mole ratios （ranging from 0.58 to 2.56）. The experimental results also showed that Dcu was positively correlated with the HCl concentration of the starting fluid. The Dcu was independent of the SiO2 mole content in the range of SiO2 content considered. No Dcu value was less than 1 in our experiments at 850 ℃ and 100 MPa, indicating that Cu preferred to enter the fluid phase rather than the coexisting melt phase under most conditions in the melt-fluid system, and thus a significant amount of Cu could be transported in the fluid phase in the magmatichydrothermal environment. The results indicated that Cu favored partitioning into the aqueous fluid rather than the melt phase if there was a high Na/K ratio, Na-rich, peraluminous granitic melt coexisting with the high Cl^- fluid.

关键词： Cu Experimental study Partition coefficient Granitic silicate melt - Aqueous fluid

Jurassic granitoid dike in Luodian, Guizhou Province: discovery and geological significance

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Acta Geochimica 2019年第1期38卷 159-172页

作者： Mingjin Zhu Aiguo Nie Yazhou Tian xinsong wang Jun Sun Guizhou University Guizhou Institute of Technology State Key Laboratory of Ore Deposit Geochemistry Institute of Geochemistry Chinese Academy of Sciences

In this paper, the Jurassic granitoid dike that intrudes into Permian diabase was reported in Luokun,Luodian County, south Guizhou. Zircon LA-ICP-MS U–Pb dating of the granitoid dike yielded an age of 164.3 ± 2.4 Ma with the e Hf(t) range from + 7.8 to + 12.1. The high contents of SiO_2(65.2%–66.8%) and total alkali(Na_2O + K_2O: 9.01%–9.95%), and low contents of Mg, Fe, Ca, P and Ti show the characteristics of alkali-rich granite. The total contents of rare earth elements range from 289.90 to 394.23 ppm. The Rb, Ba, K, Th, U and other LILE, Ta, Sr, P, Ti are enriched, and heavy rare earth elements are depleted. Petrogeochemical characteristics show that the dike was derived from a partial melting of newly-grown basaltic crust, and contaminated by crustal materials before experiencing strong fractional crystallization. The dike was formed in the intraplate post-orogenic extension stage and indicates that parental magma rose to the shallow crust through a fault. This provides new evidence of tectonic and mantle-crust magmatic activities and may contribute to regional Au mineralization in southern Guizhou and neighboring areas.

关键词： Jurassic granitoid dike Geochemical characteristics Geochronology Luodian Guizhou province

AN ASYMPTOTIC ORDER OF FOURIER TRANSFORM ON SL(2,R)

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Analysis in Theory and Applications 2003年第1期19卷 76-80页

作者： wang xinsong and Zheng Weixing (Nanjing University, China) Department of Mathematics Nanjing University Nanjing P. R. China

In this paper, a better asymptotic order of Fourier transform on SL(2,R) is obtained by using classical analysis and Lie analysis comparing with that of [5],[6] ,and the Plancherel theorem on C2i(SL(2,R)) is also obta... 详细信息

关键词： Fourier transform SL(2,R) Lie algebra Plancherel formula HS-norm

Village Elections and the Prospect of Rural Politics Studies in China

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Fudan Journal of the Humanities and Social Sciences 2016年第1期9卷 183-187页

作者： xinsong wang School of Social Development and Public Policy Beijing Normal University Beijing China

Granted by the Organic Law on Villagers＇ Committees, village elections have been held in rural China for almost 30 years. Given its large scale---ballot boxes open to 600 million peasant voters every 3 years--and its significance to the daily welfare and political rights of many peasants, village elections have been an important topic for scholars of Chinese politics.

关键词：中国农村政治学选举乡村展望村民委员会农民法律

公民参与及基层组织对新加坡人民行动党政策响应的影响

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维普期刊数据库

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社会主义研究 2015年第4期 135-141页

作者：王新松北京师范大学社会发展与公共政策学院

在公民参与有限的政治体制中实现政策响应,需要通过有效的制度设计来实现民情表达。新加坡的国会大选是政治参与的重要渠道,但因为参与渠道的单一,国家与公民间形成了庇护关系。为了增强政策响应,新加坡政府建立了严密的基层组织网络,... 详细信息

在公民参与有限的政治体制中实现政策响应,需要通过有效的制度设计来实现民情表达。新加坡的国会大选是政治参与的重要渠道,但因为参与渠道的单一,国家与公民间形成了庇护关系。为了增强政策响应,新加坡政府建立了严密的基层组织网络,国家与基层组织间的关系体现出法团主义和庇护主义特征,基层组织则与社区建立庇护关系,并通过发展社会资本来增强社区参与,最终实现民情从民众到国家的传递。然而,由于国家、基层组织和公民三者间的庇护关系较为脆弱,以及法团主义模式具有片面性,都为政策响应带来一定障碍,也对人民行动党的执政合法性提出挑战。

关键词：政策响应基层组织公民参与庇护主义新加坡

中国中产阶层的公民参与——基于城市社区调查的实证研究

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经济社会体制比较 2016年第1期 193-204页

作者：王新松张秀兰北京师范大学社会发展与公共政策学院

对中国中产阶层的公民参与的研究大多认为其政治参与度低于其他社会阶层,但很少有研究关注中产阶层对非政治类公民活动的参与。文章通过一项全国抽样调查,集中探讨城市中产阶层的社会参与状况。研究发现,中产阶层群体虽然不倾向于参与政... 详细信息

对中国中产阶层的公民参与的研究大多认为其政治参与度低于其他社会阶层,但很少有研究关注中产阶层对非政治类公民活动的参与。文章通过一项全国抽样调查,集中探讨城市中产阶层的社会参与状况。研究发现,中产阶层群体虽然不倾向于参与政治,但更倾向于参与非政治类公民活动。多元回归分析显示,中产阶层参与志愿服务的几率是其他社会阶层的1.248倍,该结果只在收入较低的中产阶层和在"体制内"单位工作的中产阶层中显著,"体制外"和更加富裕的中产阶层尚未表现出更加积极的公民参与行为。

关键词：中产阶层公民参与政治参与社会参与志愿行为

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图像扩散去噪模型的分析与改进

中国图象图形学报 2012年第8期17卷 934-945页

作者：傅绪加刘峰王信松淮北师范大学数学科学学院淮北235000 西安交通大学理学院信息科学系西安710049

总结与分析了已有图像扩散去噪模型的优缺点。在理论上明确解释了张量型扩散模型的物理意义,通过分析P-M扩散模型的局部扩散行为,提出一个新的扩散系数,进一步给出一个改进的张量型扩散模型。从主观与客观两个方面比较各种扩散去噪模型... 详细信息

总结与分析了已有图像扩散去噪模型的优缺点。在理论上明确解释了张量型扩散模型的物理意义,通过分析P-M扩散模型的局部扩散行为,提出一个新的扩散系数,进一步给出一个改进的张量型扩散模型。从主观与客观两个方面比较各种扩散去噪模型的效果都不容易,因为需要合适耦合各个模型的参数及数值离散方法等,为此给出了扩散模型统一的数值实现算法,可用来比较各个模型的去噪效果。数值模拟实验的结果表明,改进的扩散模型在有效去除噪声的同时,能很好地对图像中的边缘、角点、纹理等特征进行保护,去噪后的图像有较好的视觉效果。

关键词：扩散去噪模型扩散系数角点纹理

滇西北中甸地区休瓦促岩浆热液型Mo-W矿床S、Pb同位素对成矿物质来源的约束

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岩石学报 2015年第11期31卷 3171-3188页

作者：王新松毕献武胡瑞忠冷成彪余海军尹光侯中国科学院地球化学研究所矿床地球化学国家重点实验室贵阳550002 云南省地质调查局昆明650051

滇西北中甸地区位于义敦岛弧南段,近年来勘探及研究工作发现区内燕山晚期发育有一期重要的Mo-Cu-（W）矿化,明显区别于义敦岛弧北段同期的Sn-Ag-Pb-Zn多金属矿化,也不同于同地区印支期大量发育的斑岩型Cu矿化。目前,中甸地区燕山晚期Mo-... 详细信息

滇西北中甸地区位于义敦岛弧南段,近年来勘探及研究工作发现区内燕山晚期发育有一期重要的Mo-Cu-（W）矿化,明显区别于义敦岛弧北段同期的Sn-Ag-Pb-Zn多金属矿化,也不同于同地区印支期大量发育的斑岩型Cu矿化。目前,中甸地区燕山晚期Mo-Cu-（W）矿化成矿物质来源研究相对较弱,尚不能很好地解释这些成矿作用主要成矿元素存在差别的原因。休瓦促矿床是中甸地区代表性的燕山晚期大型岩浆热液型Mo-W矿床,前人定年结果显示成矿年龄为~83Ma。矿区内发育有三阶段的晚白垩世花岗岩,岩性主要有黑云母花岗斑岩、二长花岗岩和碱长花岗岩;且碱长花岗岩体下方还发育有萤石-长石似伟晶岩脉。矿化类型主要为石英脉型、近石英脉蚀变花岗岩型和斑岩型Mo-W矿化;矿体主要产在岩体内部,受控于北北西向断裂构造。蚀变类型有钾化、云英岩化、绢云母化及硅化等。流体包裹体测温显示成矿流体为含CO2的中高温（146.6~550.0℃）,中低盐度（3.15%~12.51%NaC leqv）的H2O-NaC l热液,可能主要来自于岩浆期后热液。多种金属硫化物与燕山晚期花岗岩具有一致的初始Pb同位素组成（206Pb/204Pb=18.610~19.460,207Pb/204Pb=15.606~15.747,208Pb/204Pb=38.815~39.410）,显示其成矿物质可能主要源于壳源岩浆作用,S同位素特征（δ34SVCDT：2.07‰~4.33‰）也显示其来自于岩浆作用。通过对比休瓦促Mo-W矿化、义敦岛弧北段同期的Sn-Ag-Pb-Zn多金属矿化及中甸地区印支期斑岩型Cu矿化,这三种与岩浆有关的热液矿化的S、Pb同位素及岩石地球化学性质,发现这三种矿化的成矿岩浆与相应的成矿元素均具有较好的成矿专属性;并指示着在燕山晚期陆内环境下,中甸地区的Mo-Cu-（W）矿化成矿物质来源于加厚的中基性下地壳部分熔融而形成的I型花岗岩,义敦岛弧北段的Sn-Ag-Pb-Zn矿化则主要来源于中酸性变沉积岩地壳的部分熔融而形成的A型花岗岩;而中甸印支期斑岩型的Cu矿化则与幔源岩浆作用有着密切的关系。

关键词：花岗岩 Mo-W矿化成矿物质来源休瓦促义敦