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1.
依据松辽盆地西南部新站地区嫩江组三段孢粉和藻类化石百分含量纵向变化特征,自下而上划分7个能识别水体盐度变化的孢粉和藻类组合：Cyathidites Pinuspollenites Dinogymniopsis组合,指示缩小的微咸水湖相沉积环境;Dinogymniopsis Leiosphaeridia Pinuspollenites组合,代表水域扩大的微咸水湖相沉积环境;Cicatricosisporites Pinuspollenites Botryococcus组合,代表水域缩小的淡水-微咸水湖相沉积环境;Dinogymniopsis Chlamydophorella Taxodiaceaepollenites组合,反映淡水与微咸水频繁交互变化的浅湖相沉积环境;Cicatricosisporites Pinuspollenites Pediastrum组合,代表水域缩小的淡水湖相沉积环境;Nenjiangella Balmula Cyathidites组合,代表水域范围较大的淡水湖相沉积环境;Cyathidites Trilobosporites Botryococcus组合,指示水域缩小的微咸水湖相沉积环境。 相似文献
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A modified version of the economic rent model is applied to the significant urban-waterfront changes which have characterized most European and North American port cities during the twentieth century. The model is at this stage conceptual, although supported by case studies, and employs elements which are characteristic of the majority of waterfront renewal literature. The model addresses four different conditions, three of which trace the evolution which has characterized the traditional inner-city port. The first analyzes the conditions prevailing prior to the late 1950s, when most ocean cargo still used the traditional harbor. The second application of the model relates to the dynamic changes which started in the late 1950s and lasted approximately 20 years, a period in which many piers and warehouses were abandoned and destroyed. The urban-waterfront renewal efforts which have occurred in both Europe and North America are analyzed in the third phase, which emphasizes boundary changes and potential and real economic rent windfalls accruing to landowners in the path of or adjacent to proposed urban-waterfront renewal efforts. The final application of the model reviews the impact on both economic rents and land uses of improvements to the shore and nearshore marine environment. 相似文献
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现场总线是用于自动化系统最底层的现场设备或仪表互联的通信网络。CAN是现场总线中的一种，具有较高的性能价格比和较强的实时处理能力。文章以采用CAN总线的通讯网络结构的校园消费系统为例，介绍在CAN总线通信中如何采用基于多线程的通信程序实现实时的接收、处理和发送数据的功能，对多个线程之问的协作关系进行了分析，以及对采用信号量实现线程的互斥和同步问题进行了详细的论述，最后给出了利用Delphi编写的线程的框架。 相似文献
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由于地质过程的复杂性及成矿过程的多期次叠加性,原始重磁异常往往是多种地质因素的混合信息,既包含区域背景异常信息,也包含与矿床(体)、矿化蚀变带以及隐伏岩体等与找矿密切相关的地质要素所引起的局部重磁异常.如何从复杂的叠加重磁异常中分离出具有找矿意义的局部异常,是当前矿产勘查和资源潜力评价工作中面临的难题之一.采用经验模态分解(EMD)方法来分解重磁异常,为提高分解的稳健性提出了用双调和样条插值(BSI)进行包罗面插值的新方法,并以云南个旧地区重磁数据为例,对其进行非线性多尺度分解,实现对区域异常与局部重磁异常的分离,揭示了深层次找矿信息并拓宽了经验模态分解方法的应用领域. 相似文献
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根据越界开采定义,提出矿山越界开采技术方法和技术路线。通过开展2012年度广东省矿山越界开采遥感调查,获取较为真实的矿山越界开采最新状况,且根据近三年广东省矿山越界开采遥感动态监测所获得的数据,得出矿山越界开采,呈日益严重的趋势。通过遥感调查与监测,指出广东省矿山越界开采存在的主要问题,并提出有益的建议和对策,希望遥感能够作为技术支撑更好地为矿政管理服务。 相似文献
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The image of nature in geomancy 总被引：1，自引：0，他引：1
Hong-Key Yoon Ph. D. 《GeoJournal》1980,4(4):341-348
The art of geomancy (feng-shui in Chinese) is concerned with choosing auspicious sites from which man can benefit. Geomancy has been one of the most important ideas which influenced man's relationships with nature in East Asia and has significantly affected the location and morphology of cities, villages, houses and graves in China and Korea. In geomancy, nature is basically interpreted in terms of the following three images, namely: (1) magical, that which is produced mysterious power to influence man; (2) personified, that which is treated as functioning system of animate organism or inanimate object; (3) vulnerable, that which can be destroyed or recovered by human action. 相似文献
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探地雷达复信号分析的几点讨论 总被引：3，自引：2，他引：3
采用H ilbert变换的复信号分析方法,求取相位时对噪声很敏感,所以分析前的滤波处理是非常重要的,常用的反正切求取相位角方法,不利于求取包含真实反射信息的相位θ(t)。针对以上两个问题,采用了与探地雷达垂向分辨能力相关的尺度,对原始数据进行了滤波操作。滤波后的数据保证了与原始数据相同的分辨能力,有效地压制了干扰信号。同时,具有良好的数学性质,为复信号分析提供了有利的条件。利用反余弦计算相角,方便了程序设计,且求得的相角易于变换为真实相角(ω0t θ(t)),为提取真正与反射信息相关的相位θ(t)提供了便利。应用优化方法求解瞬时相位、瞬时频率等信息,将真正与反射信息相关的θ(t)与ω0t分离,提高了分辨能力,同时还可得到ω0随时间变化的曲线,为分析探地雷达的频散现象提供了依据。 相似文献
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滇东北地区铅锌矿产资源丰富,就其原因可归于区内具有特征性地质环境:含矿地层是一套局限性滨-浅海环境沉积作用形成的以碳酸盐为主与砂、泥岩层呈不等厚交替出现的沉积建造,区内有较好的含矿层(碳酸盐层)与遮挡层相结合的地层成矿条件;矿区地质构造复杂,因经历了多期的构造运动,形成近于等间距排列的逆冲推覆体构造及与之相伴生的次级断裂和褶皱构造;同时,多期次的构造运动,也引起岩浆多次沿深大断裂发生侵入或喷发作用;在成矿作用上,复杂、多层次的地质构造为成矿作用提供了不同类型的导矿、容矿构造,岩浆作用一方面为成矿提供物源,另一方面为成矿作用提供热动力,为矿液加热,促使成矿热液得以循环运动,从而在有利部位发生交代作用而成矿。 相似文献
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Cüneyt Akal Osman Candan O. Ersin Koralay Roland Oberhänsli Fukun Chen Dejan Prelević 《International Journal of Earth Sciences》2012,101(1):177-194
Afyon Zone, which was derived from the Anatolide–Tauride platform during closure of the Neo-Tethys, is made up of pre-Mesozoic
basement and unconformably overlying Triassic–Early Tertiary cover series. The Afyon Zone contains widespread metavolcanic
rocks, which are dominated by rhyolite, dacite, and trachyandesite. They form a distinct volcanic succession, which is separated
from the underlying Silurian–Lower Carboniferous metacarbonates and meta-siliciclastics by a regional unconformity. Trachyandesitic
metavolcanics are made up of massive lava flows, pyroclastics and epiclastics, less frequently, domes and dikes, which were
developed on a deeply eroded subaerial landmass. U/Pb and Pb/Pb zircon geochronology yielded Lower Triassic (~250 Ma) ages,
which are interpreted as extrusion age of trachyandesitic volcanics. Based on the stratigraphic, geochronological, and geochemical
data, we suggest that these Lower Triassic magmatic rocks represent an extensional tectonic setting on the northern active
margin of the Gondwana, which led to the development of the northern branch of the Neo-Tethys. 相似文献
11.
刘代志 《大地构造与成矿学》1993,17(1):31-38
本文分析了盆地研究的历史现状、基本内容和特点,提出了盆地,特别是煤盆地深层构造地球物理研究的基本思路和方法步骤,在此基础上,给出了盆地深层构造地球物理信息处理系统的程序结构框架.最后,以鲁西西部煤盆地为例,给出了盆地深层构造的形态特征等有关处理成果图. 相似文献
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陈旭辉 《地质灾害与环境保护》2007,18(3):51-53
拟建的高层商住楼设置1～2层的地下室.工程布局存在两种方案,一种方案是将地下室开挖出的大量土方,堆筑到丁宜山上,在山顶上建设相对独立和封闭的高级别墅区;另一种方案是结合原始地形建设阶梯状的森林别墅.在阐述场地工程地质条件的基础上,从建筑布局、方案设计、施工技术、经费预算4个方面进行了对比研究,结果表明第一种方案不适宜,结合原始地形建设阶梯状的森林别墅的第二种方案较为可行. 相似文献
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A method is presented which allows the computation of the displacements and pore pressures which are generated in an elastic soil when excavation is carried out. The formulation is based on Biot's theory and is fully coupled, with consideration also given to the effects of the lowering of the water table which often accompanies the excavation of soil. Example problems are solved to illustrate the theory which has been presented. 相似文献
16.
W. Siegl 《Mineralium Deposita》1974,9(3):289-295
Epimetamorphic ores which were collected on the dumps of the mining area Arzberg-Haufenreith show relicts and structures which point to a genesis of the type Meggen respectively Rammelsberg. Other arguments for this are mica-layers rich in Ilmenite, which are very probably representing basic metamorphic tuffs. 相似文献
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中高层大气瞬态发光事件（TLEs）及可能的影响 总被引：1，自引：0，他引：1
中高层大气瞬态发光事件（TLEs）是发生于活跃雷暴上空平流层和中间层的一类快速大气放电现象。根据光辐射的形态特征和发生位置的不同,可将已发现的TLEs归纳为4类：由电离层快速向下发展的Red Sprites(又称红色精灵,红闪);由雷暴云顶部向上发展的Blue Jets（又称蓝色喷流,蓝激流）;由闪电激发的低电离层区域的圆环状放电ELVEs(Emissions of Light and VLF perturbation due to EMP Sources,又称光辐射和EMP源引起的甚低频扰动) 和由云顶向电离层快速向上发展的Gigantic Jets(又称巨大喷流)。对已有的TLEs现象学和形态特征的观测事实以及物理机制和理论研究等进行了回顾,讨论了TLEs对平流层和中间层大气以及电离层的可能影响,并提出了目前在TLEs理论方面尚未解决的问题,指出了进一步观测和理论研究的必要性。 相似文献
18.
《Journal of Structural Geology》1987,9(1):121-126
When photographs of outcrops are required for detailed and/or accurate structural work the photographic image should be parallel to the outerop surface. A method has been developed which allows oblique photographs to be corrected when processed. The method imposes certain restrictions on the combinations of camera and enlarger lenses which will yield a correctly proportioned print, and graphs are presented which predict suitable combinations for a wide range of conditions. The technique has been successfully applied to several problems, one of which is presented as an illustrative example. 相似文献
19.
充填于永康盆地内的永康群内陆河湖相沉积物,可划分为9种沉积类型,不同时期的沉积岩相组合和不同环境下的岩石学特征不尽相同,并可划出8种沉积总体,组成盆地沉积的基本构成单位。该盆地的6个主要地质界面,限定了盆地5个等时性地层单位,反映了盆地发展的5个演化阶段,称为5个沉积幕。沉积幕的叠覆,构成了永康盆地成因地层格架的整体样式。 相似文献
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Proposal of a method to define areas of landslide hazard and application to an area of the Dolomites, Italy 总被引：1，自引：0，他引：1
A numerical–cartographical method has been developed to create landslide hazard maps. This method allows the assigning of a rating to the various parameters which contribute to landslides. The parameters considered are: (1) erodibility and degradability of the rocks and Quaternary deposits; (2) permeability of the ground to identify areas prone to hydraulic overpressure; (3) the geometric ratio between discontinuities and slope, and thickness of Quaternary deposits; (4) angle of the slopes; and (5) land use. A thematic map is constructed for each factor considered which defines different areas through ratings, after which all the thematic maps are overlaid and the ratings added up (or multiplied). The map which is thus obtained is reclassified in order to create the final map of landslide hazard. This method, which has already been tested in various areas, has produced excellent results in this case too, allowing a map to be constructed which corresponds to the actual instability problems. 相似文献