Tracing leachates at waste sites using geophysical and geochemical modelling     

Bo Olofsson  Hillevie Jernberg  Andreas Rosenqvist 《Environmental Geology》2006,49(5):720-732

Tracing leachates at landfills is usually carried out using either geophysical methods or chemical analyses of groundwater. There are often problems with fingerprinting pollution sources or clarifying the spreading pattern due to a wide variety of possibilities giving similar anomalies. The aims of the project were to evaluate the advantages of combining results from multigeophysical modelling and statistical/chemical modelling in order to identify pollution sources and the spreading pattern and to test a new technique for chemical fingerprinting. The project was carried out at a landfill in central Sweden using geophysical measurements and modelling of CVES, GPR and VLF as well as chemical modelling using M3 (multivariate mixing and mass balance calculations). The results indicate that by combining geophysical modelling and chemical calculations, the possibilities of fingerprinting the origin of pollution as well as delineating the spreading pattern are significantly increased.  相似文献   

Assessment of Marine Clay Improvement Under Reclamation Fills by in-situ Testing Methods     

A. Arulrajah  H. Nikraz  M. W. Bo 《Geotechnical and Geological Engineering》2006,24(2):219-226

In ground improvement projects with prefabricated vertical drains, the duration of the preloading period is set in advance based on the predetermined time rate of consolidation of the compressible layer. If prediction is accurately done, the required degree of consolidation is met at the pre-determined preloading time. As such, there is a requirement for in-situ tests to be carried out just prior to the removal of surcharge to assess the degree of consolidation of the improved ground. In-situ tests were carried out after 23 months of surcharge loading at the In-Situ Test Site within the Changi East Reclamation Project in the Republic of Singapore. In-situ testing works in this research study comprises the use of field vane shear, piezocone, flat dilatometer and self-boring pressuremeter. The in-situ tests were carried out to determine the shear strength and degree of consolidation of the Singapore marine clay at Changi after 23 months of surcharge loading. The In-Situ Test Site consisted of a Vertical Drain Area as well as an untreated Control Area. Both areas were located adjacent to each other and were surcharged simultaneously to the same level and surcharge left in place for a period of 23 months. Comparison was made between the in-situ test results of the Vertical Drain Area and the untreated Control Area.  相似文献   

萨拉乌苏河流域萨拉乌苏组沙丘砂沉积特征   总被引：7，自引：1，他引：7  

欧先交  李保生  靳鹤龄  吴正  温小浩  董光荣  曾兰华  欧阳椿陶  杨艺  刘宇飞 《地理学报》2006,61(9):965-975

萨拉乌苏河流域米浪沟湾剖面萨拉乌苏组含7层古流动沙丘砂、4层古固定-半固定沙丘砂.对这些沙丘砂的沉积构造观察以及粒度、扫描电镜和常量化学元素分析结果表明：（1）这些沙丘砂具有与现代沙丘砂相似的风成沉积构造特征;（2）粒度及其参数——Mz、σ、Sk和Kg,以及主要化学组分SiO2、Al2O3和TOFE也与现代沙丘砂相近;（3）Mz-σ、SiO2-Al2O3＋TOFE散点图和概率累积曲线显示这些沙丘砂与萨拉乌苏组中的河湖相、古土壤差别明显,而与现代沙丘砂一致;（4）石英砂颗粒具有良好的磨圆以及碟形坑、新月形坑、麻坑、上翻解理薄片、硅质沉淀和硅质裂纹等表面结构特征,反映其曾受持久的风力搬运作用.沉积构造、粒度、石英砂颗粒表面结构和化学元素等多个方面具备了与现代沙丘砂类似的风成特征,证明这些沙丘砂的成因是风成的.  相似文献   

紫色丘陵区不同侵蚀沉积地段土壤结构特征     

况福虹  何毓蓉朱波 张保华 《山地学报》2006,24(B10):71-76

以中国科学院盐亭紫色土农业生态试验站小流域为例，研究不同土壤侵蚀沉积地段（斜坡和沟谷不同部位）的土壤结构特征，以了解侵蚀沉积对土壤结构的影响。结果表明，在植被覆盖较好的坡体顶部，土壤侵蚀较弱，团聚度达到30．1％，MWD变化为3．4mm，土壤结构良好；沟谷底部由于沉积而有较多细土物质并具有适宜的水分条件，有利于土壤团聚体的形成，结构状况亦较好，团聚度达到50．3％，结构保持率为35．4％；而坡腰侵蚀较严重，团聚度仅为13．6％，结构保持率为14．1％，土壤结构状况较差。  相似文献   

山丘平原过渡区土壤重金属污染特征及评价——以四川省五通桥区为例     

杜波  杨万勤张健 《山地学报》2006,24(B10):82-87

采集和分析了五通桥区不同功能区和乡镇73个土壤样品，以了解山丘平原过渡区土壤重金属的含量和污染特征。结果表明，重金属的平均含量为Pb32．18mg／kg、Cd0．82mg／kg、Cu28．61mg／kg、Zn108．08mg／kg、Ni32．66mg／kg、Cr72．44mg／kg；与四川土壤背景值相比，Cu、Ni、Cr的含量与之持平，Pb增加了0．11倍，Zn增加了0．32倍，Cd的积累较为严重，比背景值增加了10倍。污染评价结果显示该过渡区存在一定程度的重金属污染问题，不同功能区的污染程度排序为工业区〉生活区〉农业区。Cd在六种元素的土壤污染分担率中占55．46％，是最主要的污染元素；土壤Cd含量与Pb和Zn存在较高的相关性（相关系数为0．525和0．500），表明存在Pb—Cd和Zn—Cd的复合污染。  相似文献   

高校自然地理实践教学改革探讨   总被引：7，自引：0，他引：7  

文星跃  董廷旭 《福建地理》2006,21(2):135-137

从现代自然地理学综合性和应用性的特点出发,结合自然地理教学现状,分析了自然地理实践教学改革的必要性。阐述了加强实践教学应遵循的基本原则。提出了改革的主要途径,即调整课程内容,优化自然地理课程体系;创新实践教学手段和方法;营造良好的学术氛围和加强横向科研合作。  相似文献   

小型水电站建设用地地质灾害评估技术研究——以湄尼多河小型水电站为例     

陈春华  李波 《中国地质灾害与防治学报》2006,17(3):133-136

现阶段,地质灾害评估技术人员在评估实践中,往往不注重各评估对象的差异性,采取同一评估模式,结果达不到评估的目的。在对小型水电站进行评估时,野外调查的重点,评估过程中所使用的方法以及危险性现状、预测及综合分区评估等与大型水电站、路线工程、矿山开采、民用建筑等工程有所不同。湄尼多河小型水电站工程位于云南省怒江州福贡县马吉乡境内,地质环境条件复杂,评估级别综合为二级。文章以该电站建设用地地质灾害危险性评估为例,对小型水电站建设用地地质灾害危险性评估的方法与理论进行探讨。  相似文献   

Detrital Zircon of 4100 Ma in Quartzite in Burang, Tibet     

DUO Ji WEN Chunqi FAN Xiaoping GUO Jianci NI Zhiyao LI Xiaowen SHI Yuruo WEN Quan 《《地质学报》英文版》2006,80(6):954-956

A detrital zircon aged 4.1 Ga is discovered by the SHRIMP U-Pb method in a quartzite in Burang County, western Tibet. This is presently the oldest single-grain detrital zircon in China. The Th-U ratios of the two testing points of the 〉4.0 Ga zircon are between 0.76 and 0.86, indicating their magmatic origin. This discovery has offered an important age for investigating the geological evolution of the Qinghai-Tibet Plateau.  相似文献   

基于LBS的嵌入式GIS研究--以北京市综合交通信息平台设计为例     

晏磊  闻辉  刘岳峰  白耕  郑江华  桂智明 《全球定位系统》2005,30(3):1-8

GIS是LBS的位置定位、导航及地图表达的基础技术支撑。针对LBS的固定服务端与移动终端的信息交互需求，提出了平台GIS与移动GIS的概念；针对移动GIS，提出了嵌入式、软件插件组合技术，确定了无线下载的事件表结构；将此用于北京市交通综合信息平台设计，实现了LBS的数据与业务分离、实时信息的自动交互、移动终端的位置确定与表达。  相似文献   

地震属性分析中水平切片的应用   总被引：6，自引：0，他引：6  

国洪伟  陈勃  刘和芝  刘伟  张秀丽 《物探化探计算技术》2005,27(1):10-15

利用地震数据体中含有的丰富地质信息,可以有效地进行储层预测。层拉平水平切片地层学解释方法是先将地震剖面目的层段做层拉平处理,然后对切片顺地层层面追踪,勾绘出各种地层现象,并以地层学的观点加以解释。该方法在吉林探区扶新南部地区的应用中,对于识别河道的展布趋势取得了较好的效果,而且发现了多期叠置的扇型沉积体。另外,还可指导反演数据体的解释,做到对岩性体从定性到定量的描述。  相似文献