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131.
以研究区成矿地质背景为基础,将其划分为4个地球化学区,从多重分形理论出发,应用“元素含量—面积”模型方法,对各区主要成矿元素的地球化学(异常)场进行分析研究。结果表明,由于地质构造背景和化探元素富集的成因机理不同,各区元素地球化学(异常)场具有两种不同的多重分形特征模式:只有两个无标度区的简单多重分形模式和有两个以上无标度区的高丛集多重分形模式,具有相同成因的元素组合具有相似的多重分形特征。在此基础上.探讨了各区元素的成矿富集规律和空间分布特征,进而划分了地球化学背景和异常,经检验对比,证明了该方法的有效性和实用性。  相似文献   
132.
Most ore-forming characteristics of the Langshan-Zha‘ertaishan hydrothermal exhalation belt, which consists of the Dongshengmiao, Huogeqi, Tanyaokou and Jiashengpan large-superlarge Zn-Pb-Cu-Fe sulfide deposits, are most similar to those of Mesoproterozoic SEDEX-type provinces of the world. The characteristics include: (1) All deposits of this type in the belt occur in third-order fault-basins in the Langshan-Zha‘ertaishan aulacogen along the northern margin of the North China Platform; (2) these deposits with all their orebodies hosted in the Mesoproterozoic impure dolomite-marble and carbonaceous phyllite (or schists) have an apparent stratabound nature; ores display laminated and banded structures, showing clear depositional features; (3) there is some evidence of syn-sedimentary faulting, which to a certain extent accounts for the temporal and spatial distribution and the size of the orebodies in all deposits and the formation of intrabed conglomerates and breccias; (4) they show lateral and vertical zonation of sulfides; (5) The Cu/(Pb Zn Cu) ratio of the large and thick Pb Zn Cu orebodies gradually decreases from bottom to top; and (6) barite is interbedded with pyrites and sometimes with sphalerite. However, some characteristics such as the Co/Ni radio of the pyrites, the volcanism, for example, of the Langshan-Zha‘ertalshan metallogenic belt, are different from those of the typical SEDEX deposits of the world. The meta-basic volcanic rock in Huogeqi, the sodic bimodal volcanic rocks in the Dongshengmiao and potassic bimodal-volcanic rocks with blastoporphyfitic and blasto-glomeroporphyritic texture as well as blasto-amygdaloidal structure in the Tanyaokou deposits have been discovered in the only ore-bearing second formation of the Langshan Group in the past 10 years. The metallogeny of some deposits hosted in the Langshan Group is closely related to syn-sedimentary volcanism based on the following facts: most of the lead isotopes in sphalerite, galena, pyrite, pyrrhotite and chalcopyrite plot on both sides of the line for the mantle or between the lines for the mantle and lower crust in the lead isotope composition diagram; cobalt content of some pyrites samples is much higher than the nickel content (Co/Ni= 11.91-12.19). Some volcanic blocks and debris have been picked out from some pyritic and pyrrhotitic ores. All Zn-Pb-Cu-Fe sulfide orebodies in these deposits occur in the strata overlying metamorphic volcanic rocks in the only ore-bearing second formation. In the Jiashengpan deposit that lacks syn-sedimentary volcanic rocks in the host succession only Pb and Zn ores occur without Cu ore, but in the Dongshengmiao, Tanyaokou and Huogeqi deposits with syn-sedimentary volcanic rocks in the host succession Cu ores occur. This indicates a relatively higher ore-forming temperature. The process of synsedimentary volcanic eruption directly supplied some ore-forming elements, and resulted in secular geothermal anomaly favorable for the circulation of a submarine convective hydrothermal system, which accounts for the precipitation of deep mineralizing fluids exhaling into anoxidic basins along the syn-sedimentary fault system in the Langshan-Zha‘ertai rift. The Dongshengmiao, Tanyaokou, and Huogeqi deposits hosted in the Langshan Group appear to be a transitional type of mineral deposit between SEDEX and VMS-types but with a bias towards SEDEX, while the Jiashengpan deposit hosted in the Zha‘ertai Group is of a characteristic SEDEX type. This evidence, together with other new discoveries of Mesoproterozoic volcanic rocks and the features of lithogeny and metallogeny of the Bayun Obo deposit in the neighborhood emphasize the diversity, complexity and uniqueness of the Mesoproterozoic Langshan-Zha‘ertal-Bayun Obo ore belt.  相似文献   
133.
国内旅游文化开发研究综述   总被引:6,自引:0,他引:6  
旅游文化是一种重要的旅游资源。是旅游地可持续发展的源泉。在旅游地开发过程中,文化事项如何转化为旅游产品,即旅游文化开发是一个极具实际应用价值的研究课题。目前,国内对于旅游文化开发的研究还没有能够形成一个完整的理论研究体系,并且缺少成熟的研究方法,具体到实践中可操作性还比较弱。在查阅了国内近20年中的众多相关研究文献的基础上,试图从应用理论、开发实践、方法探索3个方面对国内的旅游文化开发研究做一个系统的总结。  相似文献   
134.
旅游文化是一种重要的旅游资源,是旅游区实现可持续发展的源泉。位于粤北连南瑶族自治县的南岗排是一个具有上千年历史的排瑶村落,至今仍保存着大量的明代与清代遗留下来的文物古迹。对于南岗排的旅游开发,应当积极发掘其丰富的旅游文化资源,并通过精心设计形成旅游产品。南岗排旅游区应以“排瑶村寨风情博物苑”为主题,重点发掘其排瑶民俗文化、宗教文化与历史文化。从文化氛围营造、专项文化开发、文化形象宣传3个方面对南岗排旅游区的文化资源开发做了探讨。  相似文献   
135.
东吴小筑园林植物应用评价   总被引:1,自引:0,他引:1  
园林植物配置是园林植物应用的重要内容,对充分发挥园林功能和观赏特性具有重要作用。通过对东吴小筑入口、前庭小院、主景区、山林区、园路、出口等6个功能区园林植物水平配置的现状调查,分析了本景区园林植物的物种多样性、水平结构、垂直结构、色彩变化等特征。结果表明:东吴小筑园林景观营造中.植物配置显示出较高水准。在树种选择、树丛组合、层次搭配、空间组织、色彩表现、季相变化等方面的设计布局十分精细,对今后园林设计及园林绿化水平的提高具有较好的指导作用。  相似文献   
136.
目前的滑坡预报模型只能利用一个关键监测点的监测数据,而不能同时利用多个监测点的监测信息,即只能处理一维时间序列问题.为了解决这个技术难题,本文将滑坡视为一个机动目标,将对滑坡的监测视为对机动目标的跟踪,提出了利用多传感器目标跟踪融合技术来处理滑坡多个点的监测数据的方法,分析了其可行性,并用实例说明了本文提出的方法在实际应用中是有效的.  相似文献   
137.
An experimental study on reduction of U (Ⅵ) by anaerobic bacteria, Shewane//a putrefaciens, is first reported here in China. The experimental conditions were: 35℃ and pH =7.0-7.4, corresponding to a physicochemical environments in which the sandstone-hosted interlayer oxidation-zone type uranium deposit formed in Northwest China's Xinjiang. Bacteria adopted in the present experiment, Shewanella putrefaciens, occur extensively in natural environment. Our study shows that nano-crystal precipitates of uraninite quickly occurred on the surface of the cells within one week. It was found that the pitchblende was characterized by a random arrangement of uraninite nanocrystals (2-4 nm) in it, significantly different from natural pitchblende in which uraninite nanocrystals are arranged in order. Finally, a possible mechanism of uranium biomineralization by microorganisms in the deposits is discussed. Our investigation may supply a technical train of thoughts for bioremediation of nuclear-contaminated water environments and for underground dissolving extraction of the sandstone-hosted uranium ores.  相似文献   
138.
Biomineralization of Uranium: A Simulated Experiment and Its Significance   总被引:5,自引:0,他引:5  
A simulated experimental reduction of U^v1 and the synthesis of uraninite by a sulfate-reducing bacteria,Desulfovibrio desulfuricans DSM 642, are first reported. The simulated physicochemical experimental conditions were:35℃, pH=7.0-7.4, corresponding to the environments of formation of the sandstone-hosted interlayer oxidation-zone type uranium deposits in Xinjiang, NW China. Uraninite was formed on the surface of the host bacteria after a one-week‘s incubation. Therefore, sulfate-reducing bacteria, which existed extensively in Jurassic sandstone-producing environments,might have participated in the biomineralization of this uranium deposit. There is an important difference in the orderdisorder of the crystalline structure between the uraninite produced by Desulfovibrio desulfuricans and naturally occurring uraninite. Long time and slow precipitation and growth of uraninite in the geological environment might have resulted in larger uraninite crystals, with uraninite nanocrystals arranged in order, whereas the experimentally produced uraninite is composed of unordered uraninite nanocrystals which, in contrast, result from the short time span of formation and rapid precipitation and growth of uraninite. The discovery has important implications for understanding genetic significance in mineralogy, and also indicates that in-situ bioremediation of U-contaminated environments and use of biotechnology in the treatment of radioactive liquid waste is being contemplated.  相似文献   
139.
成熟勘探的矿集区非常有必要开展新一轮的找矿,但矿床模式的局限和大埋藏深度等困难制约了这些地区的预测性找矿发现。促进其预测性找矿发现的关键战略包括:勘查模型的创新、勘查技术的创新和各种信息的综合集成预测。勘查模型的创新必须包含基于地球动力学剖析的新成矿概念,动力学数值模拟是有效的创新手段之一;勘查技术创新的主要目的是加大探测深度和提高探测与解释的准确性,必须以详细可靠的地质资料为基础;综合信息集成是利用GIS和知识驱动及数据驱动的方法充分提取各种数据中的有用信息,集成为更加可靠的预测图。在这种思想的指导下,我们在铜陵凤凰山矿田进行了预测和勘查,并成功地发现了深部的隐伏矿床。  相似文献   
140.
INTRODUCTIONThe Shaiwa Section is located in the town ofSidazhai, Ziyun County, Guizhou Province, south western China ( Fig. 1 ). This area belongs to theNanpanjiang basin of the Yangtze platform. A greatdeal of work purely on the subdivision of the stratahas been carried out in this region (Guizhou Bureauof Geology and Mineral Resources, 1987). However,studies on recoveries of the paleoenvironments of thisarea are rarely reported. Due to rifting and su…  相似文献   
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