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871.
介绍了2003年4月山西省永济市被中国地震局确定为社区地震应急救援试点城市后,在社区组建应急救援志愿者队伍的一系列举措及经验,认为社区作为防震减灾工作的基础单元,建立一支训练有素的应急救援志愿者队伍是非常必要的. 相似文献
872.
城市环境岩土工程的地下水灾害问题 总被引:5,自引:2,他引:5
随着城市建设的发展,人类在域市的岩土工程活动越来越频繁,由此产生一系列环境岩土工程问题。其中,由人类的工程活动引发的地下水灾害问题日趋显著,已经引起国内外专家的高度重视。地面沉降范围不断扩展,地下水永喷逐年下降,是当前城市环境岩土工程中日益突出的地下水灾害中最广泛、最严重的两大问题。它们已严重威胁着域市的可持续发展及居民的正常生活。文章概述了地面沉降及地下水水质污染现状,对抽汲地下水引起的地面沉降、建设工程性地面沉降的机理以及城市建设中可能引起的地下水点污染问题等进行了分析,针对地面沉降和地下水污染提出了相应的预防与治理措施,以实现地下水资源的可持续利用,保证城市经济及社会的可持续发展。 相似文献
873.
874.
Qi AN Shenggao CHENG Gang ZHU 《中国地球化学学报》2006,25(B08):94-94
Conservation of Urban Forest Site in Jiufeng is constructed as an ecotourism function urban forest conservation combining mountain and vegetation resource around. According to fieldwork, the conservation is located in the outskirts of the city where non-point pollution is dominant. In order to master the source intensity and its distribution, data from Quickbird remote sensing in 2004 and field collection are adopted to establish the environment database including data layers of districts, land use, map, soil map, DEM, water and road systems, soil property and economy. Traditional quantitative analysis of non-point pollution intensity has encountered with the following difficulties: (1) Large area of vegetation landscape reconstruction will create tremendous ecological benefits, but calculation of pollution decrease brought by reconstruction is difficult to achieve. (2) In conservation reconstruction will be implemented in the residential are step by step, i.e., of moving, repairing and centralization, which is a complex project with wide time span, leading to inaccurate prediction. (3) Construction of the conservation will speed up the development of local tourism, thus if a single society index is chosen to predict the pollution intensity, the development trend of the region could not be figured out completely. Consequently acreage of different planning land use is counted and models of urban and rural areas respectively help to compute unit pollution load. In the urban area, the pollution load of the same land use is regarded as the function of population density, clean frequency and precipitation, while in the rural area, SCS model, universal soil loss equation (USLE) and pollution transfer model are applied to compute unit pollution load of TN and TP. The results of total pollution load are TN 179.706 kg/a and TP 33.814 kg/a. For impracticability of routine planning measures, the project applies measures of distribution controlling against water erosion and soil loss and concentrated-dispersive controlling to lighten non-point pollution brought by living sewage. 相似文献
875.
为加强地下水管理,摸清区域含水层分布,介绍了利用现有水井,应用物探方法测量其剖面视电阻率曲线,确定含水层分布的方法。 相似文献
876.
青海省木里煤田地处高海拔、高寒环境地区,煤田在露天开采生产过程中会受到高海拔、高寒环境等恶劣气候的影响。青海省木里煤田聚乎更矿区二井田露天开采,在生产过程中易遇到冻土开挖难度大,爆破成本高,冻土消融形成蠕动滑坡、路基冻胀变形,破坏运输线路,大气降水导致剥岩进度缓慢,积水影响穿孔爆破,以及强降雨天气极易形成山洪,冲垮河道危及矿区安全等影响。矿区要合理有效地利用资源、保护矿山环境、加强监测与信息化管理,利用更好的技术手段减小高寒、高海拔坏境对露天开采的影响,实现矿业的可持续发展。 相似文献
877.
卫星导航的不确定性、不确定度与精度若干注记 总被引:2,自引:3,他引:2
卫星导航定位必然有误差。其误差可分为偶然误差、系统误差、异常误差、有色噪声等。误差存在多种不同的度量模型和度量方法,如,精密度(precision)、精确度(accuracy)、可靠性(reliability)、不确定度(uncertainty)等。实践中,经常有学者和工程技术人员将精度指标描述成误差,也有人将不确定性与不确定度概念相混淆。尤其是在描述精度指标或误差指标时,经常将精度指标描述成误差,将误差指标描述成精度,如在卫星导航定位中,用户距离误差经常被描述成用户距离精度。本文基于不确定度概念将卫星导航中的用户距离误差重新作了定义;给出了用户距离误差与用户距离精度的关系;并提出将不确定性与不确定度进行区别;对测量平差中常用的可靠性概念进行了描述;最后给出了几点注记。 相似文献
878.
崩塌与滑坡是耒阳市的主要地质灾害类型,通过对其发育特征及成生因素的初步探讨,分析并提出了该市崩塌与滑坡的差异性和共同点,针对具体事例论证了以暴雨为主要诱发因素导致的崩滑现象具有明显的阶段性和复活性,提出了今后有效治理崩滑的防治措施和建议,可供地方防灾减灾借鉴参考。 相似文献
879.
《China Geology》2020,3(1):38-51
Coal measure gas (also known as coal-bearing unconventional gas) is the key field and development direction of unconventional natural gas in recent years. The exploration and evaluation of coal measure gas (coalbed methane, coal shale gas and coal measure tight sandstone gas) from single coalbed methane has greatly expanded the field and space of resource evaluation, which is of positive significance for realizing the comprehensive utilization of coal resources, maximizing the benefits and promoting the innovation of oil and gas geological theory and technological advances in exploration and development. For the first time, in Yangmeishu Syncline of Western Guizhou Province, the public welfare coalbed methane geological survey project of China Geological Survey has been carried out a systematic geological survey of coal measure gas for the Upper Permian Longtan Formation, identified the geological conditions of coal measure gas and found high quality resources. The total geological resource quantity of coalbed methane and coal shale gas is 51.423×109 m3 and the geological resource abundance is up to 566×109 m3/km2. In this area, the coal measures are characterized by many layers of minable coal seams, large total thickness, thin to the medium thickness of the single layer, good gas-bearing property of coal seams and coal measure mudstone and sandstone, good reservoir physical property and high-pressure coefficient. According to the principle of combination of high quality and similarity of key parameters of the coal reservoir, the most favorable intervals are No.5−2, No.7 and No.13−2 coal seam in Well YMC1. And the pilot tests are carried out on coal seams and roof silty mudstone, such as staged perforation, increasing hydraulic fracturing scale and “three gas” production. The high and stable industrial gas flow with a daily gas output of more than 4000 m3 has been obtained, which has realized the breakthrough in the geological survey of coal measure gas in Southwest China. Based on the above investigation results, the geological characteristics of coal measure gas in the multi-thin-coal-seam-developed area and the co-exploration and co-production methods, such as the optimization method of favorable intervals, the high-efficiency fracturing and reservoir reconstruction method of coal measures, and the “three gas” drainage and production system, are systematically summarized in this paper. It will provide a reference for efficient exploration and development of coal measure gas in similar geological conditions in China. 相似文献
880.
露天矿潜滑体边坡变形、失稳模拟分析 总被引:4,自引:0,他引:4
在对布沼坝露天矿西北帮潜滑体边坡工程地质条件进行分析的基础上 ,应用连续介质快速拉格朗日元法 ( FLAC) ,对潜滑体边坡实施的控制措施进行了模拟分析与讨论 相似文献