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61.
分形、混沌理论在藏东矿产资源预测及评价中的应用 总被引:4,自引:0,他引:4
本文主要探讨分形,混沌理论在藏东地区矿产资源预测及评价中的应用,藏东地区资源丰富,但地处自然环境恶劣的三江水系强烈切割区,在这种西部特殊景观区的资源评价需要有与之相配套的新技术方法,文中详细分析了应用分形,混沌理论确定BUFFER分析参数的方法,效果以及分形,混沌理论在元素地球化学异常筛选中的应用,指出应用分形,混沌理论能够指导找矿,缩小靶区,提高矿产资源预测评价的效果。 相似文献
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雄村矿区位于拉萨地体南缘的冈底斯成矿带,通过对雄村矿区新发现的Ⅲ号矿体硫、铅同位素的综合分析研究,探讨了成矿物质来源问题。研究表明,矿石金属硫化物的δ34S在-1.3‰~1.4‰之间,平均值为-0.85‰,分布范围较窄,成矿热液的δ34SΣS值为-0.04‰,均显示出幔源硫的特征。矿石金属硫化物的铅同位素206Pb/204Pb比值变化于18.204~18.468之间(平均值为18.359),207Pb/204Pb比值变化于15.549~15.593之间(平均值为15.567),208Pb/204Pb比值变化于38.213~38.441之间(平均值为38.351),铅同位素组成特征值μ变化于9.37~9.45之间(平均值为9.40);在铅同位素判别图解上位于造山带铅同位素演化线附近,显示出地幔物质与俯冲沉积物的混合特征,暗示金属硫化物中的铅源自地幔,并有少量俯冲沉积物的加入。 相似文献
64.
在中高纬度水域,近海与海洋生产建设不可避免的要遭遇冰的影响,尤其在冬季。因此,认真研究海冰的基本物理性质和本构特征尤为重要。对取自大凌河口的两根海冰冰样进行分析,沿厚度连续地自上而下竖直切片,并且等间距地水平切片,在正交偏光镜下观测冰晶结构;同时测量了每个样本不同位置的密度、盐度和含泥量以及分析其孔隙率;最后探讨了这些物理量之间的关系。结果得到:冰样上层为颗粒状晶体,中下层为柱状晶体;气泡多为球形,百分含量较低;冰密度在860~930kg/m3之间,盐度随深度呈C字型变化。 相似文献
65.
The in situ sea-ice temperature, salinity and density observed from Chinese Antarctic Zhongshan Station have been applied to calculate the vertical profile of sea ice porosity. Based on numerical method, a number of schemes on sea-ice thermal diffusivity versus porosity have been accessed and one optimized scheme is identified by an optimal control model with an advanced distributing parameter system. For simplicity, the internal heating source item was neglected in the heat conduction equation during the identification procedure. In order to illustrate the applicability of this identified scheme, the vertical ice temperature profiles have been simulated and compared with measurements, respectively by using identified scheme and by classical thermodynamic formulae.The comparisons indicated that the scheme describing sea-ice thermal diffusivity and porosity is reasonable. In spite of a minor improvement of accuracy of results against in situ data, the identified scheme has a more physical meaning and could be used potentially in various applications. 相似文献
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Forty four core samples were analyzed to determine sediment particle size, total organic carbon (TOC), total inorganic carbon (TIC), total nitrogen and total sulphur. Sequential extraction of S was also carried out, differentiating AVS (acid volatile sulphide), elemental S, organic S and pyrite S. The results obtained show that the presence of mussel rafts causes intense changes in the physicochemical composition and properties of the sea floor in the Ria de Arousa. The percentage of silt and clay, TOC, TIC and total N were significantly higher in the biodeposit than in the sediment. In contrast, there were no differences between the biodeposit and the sediment in terms of pH (8.0-8.7) and redox potential. The sediment and biodeposit were always anoxic, with values of redox potentials below -100 mV. In accordance with these conditions, the dominant fraction of S was pyrite S (FeS(2)). The AVS fraction and elemental S were present at low concentrations, except in the uppermost part of each core. Pyrite was relatively stable when the biodeposit and sediment were maintained in suspension for 8 days in oxic sea water; unlike the AVS fraction, which disappeared within a few hours. 相似文献
68.
The vertical temperature profiles of snow and sea ice have been measured in the Arctic during the 2nd Chinese National Arctic Research Expedition in 2003(CHINARE2003).The high-resolution temperature profile in snow is solved by one-dimensional heat transfer equation.The effective heat diffusivity,internal heat sources are identified.The internal heat source refers to the penetrated solar radiation which usually warms the lower part of the snow layer in summer.By temperature gradient analysis,the zero level can be clarified quantitatively as the boundary of the dry and wet snow.According to the in situ time series of vertical temperature profile,the time series of water content in snow is obtained based on an evaluation method of snow water content associated with the snow and ice physical parameters.The relationship of snow water content and snow temperature and temporal-spatial distribution of snow water content are presented 相似文献
69.
利用山东省9月份平均降水量、NCEP再分析500hPa高度场资料和NOAA再分析海温资料,采用相关分析方法,在前期500hPa高度场和海温场上挑选出影响山东省9月份降水的关键区域,把关键区域内的资料进行区域平均,并做归一化处理,形成因子集,进行相似离度计算,确定出相似年份,预报9月份降水量距平百分率。将1997-2005年作为试报年,结果报对7年,准确率为77.8%,可见,相似离度方法在月尺度短期气候预测中有一定的应用价值。 相似文献
70.
Fabric and crystal characteristics of Bohai and Arctic sea ice 总被引:1,自引:0,他引:1
1 IntroductionBohaione yeariceandAntarcticonehavethesimilarsurface featuresandcorre spondingfabricandcrystalcharacteristics (Allison 1 997;Lietal.1 997;Qin 1 991 ) .DuringtheChinaFirstArcticExpedition ,theresultsinthestudyofone yearicefromBohaiandAntarcticwereusedfo… 相似文献