Contribution of the geophysical methods in characterizing the water leakage in Afamia B dam, Syria   总被引：1，自引：0，他引：1  

Walid Al-Fares 《Journal of Applied Geophysics》2011,75(3):464-471

The objective of this work was to characterize and understand the origin of the water losses problem in the Afamia B dam located at Al-Ghab basin in Syria. The survey involved various geophysical methods including a superficial electromagnetic (EM), an electrical sounding (ES) and electrical resistivity tomography (ERT). Special considerations were focused on the lake of the dam, which is currently suffering serious water infiltration and leakage through its bedrocks. The application of the ERT technique was more effective and convenient. The analysis of the integrated results of the above mentioned methods revealed a vertical serious leakage which could take place in certain locations via fractures and faults that hit the main valley and pass through the dam lake. Additionally, the presence of an alternating lithological heterogeneity between permeable and impermeable layers may lead to infiltration through the geological formations of the basin. These processes are most likely causing hydraulic connections between the Neogene superficial deposits and the underlying Cretaceous fractured and karstified carbonates rocks. Consequently, such hydraulic connections may lead to water losses and leakage throughout the dam basin. Eventually, the presence of tens of drilled wells which penetrate the Neogene and Cretaceous formations, and the existence of numerous archeological graves and subsurface tunnels complicate the situation in the study area and cause more water leakage.  相似文献   

高能偏振能量色散-X射线荧光光谱法测定PM₁₀大气颗粒物的组成   总被引：2，自引：1，他引：1  

吉昂  郑南  王河锦  徐子优  李国会 《岩矿测试》2011,30(5):528-535

为配合X射线衍射分析(XRD)方法对可吸入大气颗粒悬浮物(PM10)的结晶物相进行定性和定量分析的研究工作,本文应用高能偏振能量色散X射线荧光光谱(HE-P-EDXRF)对Whatman玻璃纤维滤膜采集的PM10颗粒物中主、次量元素进行定量分析,着重研究了空气滤膜空白值对测定PM10颗粒物中组成的影响。结果表明,当玻璃纤维滤膜空白值中元素的面密度大于0.1μg/cm2时,需使用玻璃纤维滤膜为载体的标准样品;元素的面密度小于0.1μg/cm2时,可用聚碳酸脂膜为载体的标准样品。对HE-P-EDXRF谱仪测定PM10颗粒物中痕量重元素进行探讨,将测定元素范围扩展到62个元素,其中Na、Mg、S、Y、Nd、Sm、Eu、Gd、Tb、Dy、Ho、Er、Tm、Yb、Lu的检岀限>0.1μg/cm2;Ca、Cr、Mn、Fe、Co、Ni、Cu、Zn、Br和Rb的检岀限<0.01μg/cm2;Cl、Al、Si、P、K、Sc、Ti、V、Ge、As、Br、Se、Sr、Zr、Mo、Pd、Rh、In、Nb、Ag、Cd、Te、Sb、Sn、Ba、Cs、La、Ce、Pr、Au、Pt、W、Tl、Pb、Bi、Th和U等元素检出限为0.1～0.01μg/cm2。  相似文献   

Water body mapping method with HJ-1A/B satellite imagery     

Shanlong Lu  Bingfang WuNana Yan  Hao Wang 《International Journal of Applied Earth Observation and Geoinformation》2011

This paper proposes an integrated water body mapping method with HJ-1A/B satellite imagery, the CCD (charge coupled device) data of the Chinese environmental satellites that were launched on September 6th, 2008. It combines the difference between NDVI and NDWI (NDVI–NDWI) with SLOPE and near-infrared (NIR) band. The NDVI–NDWI index is used to enhance the contrast between water bodies and the surrounding surface features; the topographic SLOPE is used to eliminate the mountain shadow; and the NIR band is used to reduce the effects of artificial construction land. The objectives are evaluating the potential of the HJ-1A/B imagery on water body monitoring, and proposing ideally mapping method. The test study results indicated that the NDVI–NDWI index is superior to the single index of NDVI and NDWI to enhance the contrast between water bodies and the rest of the features. On the basis of the accurately mapped water bodies in the HJ-1A/B CCD images of the study area, we conclude that the HJ-1A/B multi-spectral satellite images is an ideal data source for high spatial and temporal resolution water bodies monitoring. And the integrated water body mapping method is suitable for the applications of HJ-1A/B multi-spectral satellite images in this field.  相似文献   

基于Silverlight的工业经济地理信息系统设计与实现     

袁月  刘强 《四川测绘》2011,(6):274-277

为了提高WebGIS响应效率,满足用户对高交互性和炫酷界面的需求,提出采用RIA（丰富互联网应用程序）技术改善WebGIS传统结构模式存在的问题,介绍各种RIA技术并对比总结其优缺点,详细分析新兴的微软Silverlight技术特点,针对应用系统功能需求,利用Silverlight技术在ArcGISServer10平台上设计并实现基于RIA的成都市工业经济GIS系统,验证Silverlight在WebGIS富客户端的可行性。  相似文献   

11:0000土地利用现状图制图综合研究   总被引：1，自引：0，他引：1  

马晶  毕强  崔利  朱伟刚  朱连军 《测绘科学》2011,36(3):76-78

本文基于我国传统的土地利用制图综合方法速度慢、精度差的现势,借助ArcG IS软件的可视化及空间分析工具和国源软件,将地图综合过程分解,合理地进行人机分工,交互式地完成地图缩编工作。这种缩编的方式可以更快速、高效地对基础数据进行制图综合,从而满足土地管理部门对不同比例尺土地利用现状图的用图需求。  相似文献   

基于RIA地理信息共享平台的运维系统研究     

严立  陶虹  李明峰  钱程扬 《现代测绘》2011,34(3)

运维系统是保证整个地理系统共享平台正常运行的重要组成部分,具有业务流程复杂,数据交互需求大等特点,由于基于B/S模式的传统Web应用程序在页面交互、数据可视化、传输效率等方面弱点制约其在运维系统中的应用,本文引入RIA技术有效解决上述问题。研究了RIA基本原理及应用可行性,并设计了基于该技术的Web应用程序结构模型。最后通过系统的实例运行,表明基于RIA的运维系统具有良好的性能。  相似文献   

The opposing effects of climate change and socio-economic development on the global distribution of malaria   总被引：1，自引：0，他引：1  

Andreas Béguin  Simon Hales  Joacim Rocklöv  Christofer Åström  Valérie R. Louis  Rainer Sauerborn 《Global Environmental Change》2011,21(4):1209-1214

The current global geographic distribution of malaria results from a complex interaction between climatic and non-climatic factors. Over the past century, socio-economic development and public health measures have contributed to a marked contraction in the distribution of malaria. Previous assessments of the potential impact of global changes on malaria have not quantified the effects of non-climate factors. In this paper, we describe an empirical model of the past, present and future-potential geographic distribution of malaria which incorporates both the effects of climate change and of socio-economic development. A logistic regression model using temperature, precipitation and gross domestic product per capita (GDPpc) identifies the recent global geographic distribution of malaria with high accuracy (sensitivity 85% and specificity 95%). Empirically, climate factors have a substantial effect on malaria transmission in countries where GDPpc is currently less than US$20,000. Using projections of future climate, GDPpc and population consistent with the IPCC A1B scenario, we estimate the potential future population living in areas where malaria can be transmitted in 2030 and 2050. In 2050, the projected population at risk is approximately 5.2 billion when considering climatic effects only, 1.95 billion when considering the combined effects of GDP and climate, and 1.74 billion when considering GDP effects only. Under the A1B scenario, we project that climate change has much weaker effects on malaria than GDPpc increase. This outcome is, however, dependent on optimistic estimates of continued socioeconomic development. Even then, climate change has important effects on the projected distribution of malaria, leading to an increase of over 200 million in the projected population at risk.  相似文献   

文昌B凹陷陡坡带珠海组二段海侵扇三角洲储层特征及油气成藏特征   总被引：1，自引：0，他引：1  

张迎朝  陈志宏  李绪深  徐新德 《矿物岩石》2011,31(2)

利用构造、层序地层、沉积古地貌、沉积微相分析、成藏综合分析等方法,对珠江口盆地文昌B凹陷陡坡带特殊构造背景下的珠海组储层沉积相及其油气成藏模式进行研究,认为该区珠海组二段与珠海组一段构成了一套优质区域性储盖组合,珠海组二段沉积期,在陡坡带古丘地貌上发育潮控海侵退积型扇三角洲相,其水下分流河道骨架砂岩较好的孔渗性使珠海组二段成为油气优势运聚成藏层系,是主要勘探目的层之一。结合烃源岩、沟源断裂及圈闭等成藏主控因素分析,提出该区珠海组二段垂向运移、优势聚集、有效断块的油气成藏模式,钻探发现文昌B凹陷陡坡带X构造整装规模储量的商业性油田和一批含油构造。  相似文献   

扎龙湿地水旱交错区土壤呼吸研究   总被引：1，自引：0，他引：1       下载免费PDF全文

杨柯  刘国栋  刘飞  赵传冬  刘应汉  彭敏  李括  聂海峰  李玥 《地学前缘》2011,18(6):94-100

湿地作为陆地生态系统的重要组成部分,被认为是重要的碳汇。近几十年来,湿地围垦造成土壤有机碳损失严重。全球湿地土壤的CO2温室气体排放已经相当于全球总排放的1／10。研究湿地土地利用类型的改变对土壤呼吸的影响,将有利于了解湿地碳循环,计算碳收支,制定相应对策缓解碳排放。利用LI-8100A动态密闭气室测量法,于2011年...  相似文献   

拉萨夏季大气热源10~20 d的振荡特征   总被引：1，自引：1，他引：0       下载免费PDF全文

罗璇  王盘兴  吴息  李丽平 《大气科学学报》2013,36(3):309-315

利用逐日大气热源资料分析1950-2006年拉萨夏季大气热源的气候及其异常特征。结果表明:1)拉萨夏季大气热源的气候平均值为88 W·m^-2,明显低于亚洲季风槽区夏季热源的气候平均值,是一般强度的大气热源区。20世纪90年代中期拉萨夏季大气热源趋于减弱,21世纪初其值接近于0。2)拉萨夏季57 a大气热源10~20 d振荡强度约为季节内振荡平均强度的2倍,显著年数(33 a)占总年数的57.6%,因此10~20 d振荡是拉萨夏季大气热源季节内振荡的重要分量。3)拉萨夏季大气热源10~20 d振荡强度存在明显的季节内变化(7月上旬前后振荡最强)和明显的年代际差异(20世纪50年代末-60年代中、80-90年代前期是两个强振荡阶段)。  相似文献