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51.
云南腾冲热泉金的有机地球化学研究——Ⅰ生物标志物浅析 总被引:1,自引:1,他引:1
本文主要通过对比分析研究热泉软泥中的金含量与有机质及含硫化合物的相关性。并测定泉水及软泥中含金量和软泥中有机碳含量,以及对抽提物中的饱和烃和芳烃族组分进行色谱—质谱分析,最后得出的结论:有机质的沉积环境为还原—强还原,有机质属于腐泥-腐殖型,接近和达到了成熟阶段。软泥中金含量与有机质的性质无明显相关关系,与有机碳含量也无明显相关关系,而与其成熟度相关密切。样品分析证实软泥中含硫化合物与金含量呈正相关性。对比分析了水及软泥中金含量,认为两者之间也无明显相关关系 相似文献
52.
闽西北地区隐爆作用与火山岩型铀矿化 总被引:1,自引:0,他引:1
隐爆角砾岩体对火山岩型铀矿化的控制作用已为实践所证明,并引起高度重视。本文阐述了闽西北地区隐爆角砾岩形成的时空条件、与围岩的关系、分带性及其鉴别要素。以实例说明隐爆角砾岩体对铀矿化起控制作用的3种主要形式,指出了寻找隐爆角砾岩体的方法。 相似文献
53.
论述了钻孔灌注桩常见现场事故的预防,分析和治理等方面的几个问题,叙述了钢筋笼上浮,导管堵塞,钢筋笼掉入孔内,导管提出混凝土面,掉钻头,串孔等事故的原因和处理方法及预防措施。 相似文献
54.
在地震预报研究中,地电阻率变化形态被作为地震预报的一种前兆手段.迄今为止,国内外已经做了许多不同加载方式的室内和室外岩石或样品的电阻率变化实验,积累了相当丰富的承载岩石或样品的电阻率变化资料.本文介绍部分不相似的实验结果,以促使此项研究进一步深入发展. 相似文献
55.
Using data from the intensive observation period (May–June 2000) of the NWC-ALIEX (The Field Experiment on Interaction between Land and Atmosphere in Arid Region of North-west China), the characteristics and mechanisms of some key land-surface process over Gobi in a typical arid region of north-west China are analyzed and several parameters of land-surface processes are calculated. The weighted mean of the surface albedo over a typical arid region of the Dunhuang Gobi is calculated using the relative reflection as a weighting factor, and its value is 0.255 ± 0.021. After removing the influence of precipitation, the mean soil heat capacity over a typical arid region of the Dunhuang Gobi is 1.12 × 106 J m-3 K-1,which is smaller than that observed in the Heihe (China) River basin Field Experiment (HEIFE). The mean soil heat diffusivity and conductivity are about half of those observed in HEIFE. 相似文献
56.
57.
A fast intensity-hue-saturation fusion technique with spectral adjustment for IKONOS imagery 总被引:11,自引:0,他引:11
Te-Ming Tu Huang P.S. Chung-Ling Hung Chien-Ping Chang 《Geoscience and Remote Sensing Letters, IEEE》2004,1(4):309-312
Among various image fusion methods, intensity-hue-saturation (IHS) technique is capable of quickly merging the massive volumes of data. For IKONOS imagery, IHS can yield satisfactory "spatial" enhancement but may introduce "spectral" distortion, appearing as a change in colors between compositions of resampled and fused multispectral bands. To solve this problem, a fast IHS fusion technique with spectral adjustment is presented. The experimental results demonstrate that the proposed approach can provide better performance than the original IHS method, both in processing speed and image quality. 相似文献
58.
澜沧江中游某崩塌堆积体变形空间效应研究 总被引:7,自引:0,他引:7
某崩塌堆积体范围内布置有公路、缆机平台、电站进水口等重要建筑物。其变形稳定性直接影响到治理工程设计、施工安全以及电站的运行。因此,文章在对其环境地质条件、物质结构、形成机制分析的基础上,对其变形空间效应作系统的地质分析;并建立了相应的三维地质力学模型,应用FLAC-3D快速拉各朗日差分程序对其空间变形特征进行了详细的分析。结果表明:收口转向及变形收敛特征使得堆积体下部形成一个“支撑拱”,从而阻碍了上部堆积体向下部的变形与位移,利于堆积体的稳定;同时,三维数值模拟结果也表明:堆积体的变形具有明显的空间效应。其位移矢量表现出一定的收敛性,且变形主要分布在1360~1650m高程;变形方式表现出一定的分区特征,表现出后缘压缩固结,中部滑移,前缘受阻压缩的位移特征。纵向具有明显的收口效应;横向上比较来看,也存在变形受阻的收口特征;收口范围主要集中在1330~1440m高程范围。 相似文献
59.
Chen-Tung Arthur Chen Jiunn-Tzong Wu Bing-Jye Wang Kuo-Ming Huang 《Aquatic Geochemistry》2004,10(1-2):33-57
One hundred and eighty lakes, ponds and reservoirs in Taiwan, and the offshore islands have been investigated since 1985. Effects such as warming/cooling, mixing, photosynthesis and respiration on pH have been identified. These effects were found to be less profound than those resulting from the geology. Since there is little rain or lake water pH data available prior to 1970, it was necessary to use proxy data in order to ascertain the history of lake acidification. In this study, we present data based on diatoms in a sediment core collected from a lake in the remote subalpine region of southern Taiwan. The acidity of this lake water was found to have increased since 1900. We measured the concentrations of 55 chemical species in lake water samples. In addition, concentrations of 26 chemical species were obtained from sediments. Conductivity, alkalinity (HCO3 ?), most other major and minor chemical species, as well as the non sea-salt SO4/Na ratio in lake water clearly decrease with elevation. Distribution of pH is similar, although the trend is less clear. Distribution of trace metals, however, shows a different trend as anthropogenic pollution, diagenetic reduction and lake acidification are at play. 相似文献
60.
This paper explores the concept of sustainable tourism and how it applies to urban destinations such as Singapore. As tourism is an important industry in Singapore, in terms of employment, business activity and an income generator, the Singapore Tourism Board is continuously looking at potential avenues to make Singapore a competitive destination. We examine the use of thematic zones in Singapore as a strategy to achieve its ambition of becoming a tourism capital of the world. By focusing on a case study of the Singapore River thematic zone (one of the 11 thematic zones identified by the Singapore Tourism Board), we assess the viability of thematic zones in ensuring sustainable urban tourism. The paper closes with some theoretical reflections and policy implications arising from our key findings. 相似文献