汶川大地震诱发地质灾害主要类型与特征研究   总被引：9，自引：1，他引：8  

许强 《地质灾害与环境保护》2009,20(2):86-93

“5．12”汶川大地震诱发了数以万计的次生地质灾害,对灾区人民生命财产安全构成严重威胁,并成为影响灾区灾后恢复重建的重要因素之一。本文在对汶川I地震区地质灾害进行大量现场调查的基础上,结合室内分析模拟,对汶川地震诱发的滑坡、崩塌、不稳定斜坡（震裂山体）和泥石流等主要次生地质灾害的主要类型及特征进行了较系统地分析研究。结果表明,强震诱发滑坡灾害发生特点与岩性结构和地形条件有较明显的关系,在硬岩、软岩和松散堆积物分布区,滑坡的启动、运动和停积形式有较大的差别,但总体上都具有高速、高动能、强大动力等特征。强震诱发的崩塌主要包括高位大型崩塌;小规模块石崩落、抛射;崩塌诱发大规模滑坡3类。强震条件下大多数崩塌都表现出一定的水平抛射特征。强烈的地震动力使极震区众多山体大范围震裂松动,形成了大量震裂山体。这些震裂山体的地表裂缝具体又可细分为断裂裂缝、震裂裂缝和滑裂裂缝3类。汶川地震形成了巨量泥石流物源,再加上震后泥石流爆发的临界降雨量大大降低,其启动和运动方式发生明显改变,在今后数年内,泥石流将是影响灾区恢复重建的最大地质灾害隐患,应高度重视,采取切实有效措施加以防范。  相似文献   

A modified EK method with an I<Superscript>−</Superscript>/I<Subscript>2</Subscript> lixiviant assisted and approaching cathodes to remedy mercury contaminated field soils     

Zhemin Shen  Jianda Zhang  Liya Qu  Zeqin Dong  Shenshen Zheng  Wenhua Wang 《Environmental Geology》2009,57(6):1399-1407

Wanshan mercury mine is the largest cinnabar deposit in Guizhou, China. Few effective methods had been achieved to remedy Hg heavily contaminated field soils. In this paper, a modified EK method with approaching cathodes (AC-EK) and an I⁻/I₂ lixiviant was described to remedy mercury-contaminated field soils near Wanshan mercury mine. Paddy Soil I and Paddy Soil II were sampled and contained 576.73 ± 45.50 and 491.35 ± 4.73 mg/kg Hg, respectively. Although they contained 6.9 and 9.4% organic matter respectively, more than 92 and 89% Hg were removed by AC-EK within 5 days. Removal ratio increased by 0.21 and 0.68 times using EK process with ACs over that with one single cathode (SC-EK). AC-EK method saved nearly 26.4–28.1% electric power as compared to SC-EK method. As an I⁻/I₂ lixiviant solution was used to solubilize HgS(HgO) during EK process, the bonding of Hg to organic functional S groups should be less important than the binding to inner sites of organic matter in soil. The relationship between EK remediation effect and soil organic matter content was fitted to a linear model. It turned out that when soil OM increased by 1.0%, EK removal ratio (%) of Hg would decrease by 2.63%.  相似文献   

微生物修复石油污染地下水的实验研究   总被引：6，自引：0，他引：6  

张胜  BI Er-ping  毕二平  陈立  崔晓梅  张翠云  韩占涛  赵红梅  张发旺  李政红 《现代地质》2009,23(1)

为修复陕北黄土区石油污染地下水,采用优化土著微生物菌群的生物技术,进行了地下水中石油的降解与修复实验研究。在实验装置内加入了1.5%的优化菌群制剂,优化出的菌群初步鉴定主要有:假单胞菌属、微球菌属、放线菌属、真菌类的青霉属和曲霉属等。实验结果显示,在实验装置中人为添加石油含量为182.5 mg/l、862.5 mg/l、1695.0 mg/l时,经过28~37 d的微生物修复,地下水中石油的降解率为27.47%~92.46%,而无菌对照中的石油含量变化在5%以内,说明在无菌条件下地下水中石油降解缓慢。该实验过程验证了微生物修复技术在地下水石油污染修复中的有效性,探索了应用的可行性。  相似文献   

AB-DTPA提取法在重金属污染土壤修复模拟试验中的应用可行性   总被引：2，自引：0，他引：2  

陈燕芳  刘晓端  谭科艳 《岩矿测试》2010,29(2):131-135

将碳酸氢铵-二乙三胺五乙酸(AB-DTPA)提取重金属生物有效态的方法应用于重金属污染土壤修复的模拟试验中,该土壤的污染元素主要是铜、锌和镉,试验所用修复材料是钠化膨润土。研究表明,AB-DTPA提取法具有很好的稳定性,而且能准确指示铜、锌、镉元素在土壤中的有效态含量,同时AB-DTPA对土壤中铜、锌、镉元素的提取率也适用于模拟试验中修复效果的平行对比。AB-DTPA提取法在重金属污染土壤修复模拟试验中的应用是可行的。  相似文献   

南疆铁路K230段冻土区滑坡泥石流勘察整治     

张俊德  张志强 《中国地质灾害与防治学报》2010,21(3):43-45

本文结合南疆铁路K230滑坡、泥石流的勘察与治理工程设计,深入分析了冻土地区滑坡的成因,滑面特性,泥石流产生的原因等,进而针对原因分析提出了采用对原地层扰动较小的锚索框架治理滑坡、采用拦挡坝治理泥石流,且采用保温盲沟疏排地下水的综合治理措施。该段地质病害的成功治理,对类似冻土地区地质病害的勘察与整治具有一定的借鉴意义。  相似文献   

河北平原地下水NO3^-污染的原位微生态修复   总被引：2，自引：0，他引：2  

张胜 张云张翠云  张凤娥孙振华荆继红  李政红张明 《地质通报》2006,25(5):609-615

以地下水NO3^-污染为例,利用优选的菌群刺剂和少量营养碳源,在河北平原进行了NO3^-污染地下水的原位微生态修复试验.试验结果显示,地下水NO3^-含量在58～72.66mg/L时,经4.5～10天的修复试验,地下水中NO3^-含量降低至7.38～0.85mg/L,去除率达到86.5%～98.8%,去除效果较好,持续时间长.该方法为修复治理大面积地下水NO3^--N污染提供了可行的技术支撑.  相似文献   

Environmental impact of gold tailings and the long-term implications for remediation and mine closure——The Far West Rand goldfield, South Africa     

《中国地球化学学报》2006,25(B08):39-39

Commercial gold mining of the Witwatersrand Supergroup in the Far West Rand goldfields of South Africa started early in the previous century and produced U as a by-product. Grades of up to 1000 mg/kg, was achieved between 1952 and 1991. Before and after this period large amounts of U brought to the surface as part of the gold ore-material were deposited as solid-water-mixtures （sludge） on slimes dams. Tailings of gold mines in the Witwatersrand basin therefore contain elevated levels of radioactive and chemo-toxic heavy metals. Mining for gold occurs at great depths below the Transvaal Supergroup dolomite. The inflow of water from the overlying dolomite aquifers resulted in substantial volumes being pumped continuously from the mine void to prevent flooding. Since large-scale dewatering of the dolomite compartments was allowed for mining, extensive sinkhole formation occurred. Between 1960 and 2000, these sinkholes and other subsidence features were back：filled as part of rehabilitation program, using a mixture of mine tailings and cement. Many of the gold mines are reaching the end of their economic viability and will close down in the next few years. Dewatering of the dolomite water compartments will come to an end resulting in a gradual rise in the water table. The uncontrolled rise of the water table to pre-mining levels will not only result in further land degradation due to renewed ground instability but also may also lead to uncontrolled pollution and acid mine drainage imminent from slimes filled sinkholes and cavities Furthermore, gold tailings facilities were placed on well-drained dolomite, resulting in seepage of dissolved U from tailing deposits into the dolomitic aquifer. The majority of the studies into mining-related pollution conducted thus far focused either on point-discharges of mining effluents into surface streams or on erosion of tailing particles from slime dams as contamination sources. This paper investigates the magnitude of land degradation and pollution potential of the sinkholes filled by tailings and cement. A combination of LIDAR and Aerial magnetic and radiometric techniques are used to localize sinkholes, structures such as dykes and faults along which polluted water will be transported from slimes and tailings into the aquifer.  相似文献   

Remediation of electric arc furnace dust leachate by the use of cementitious materials： A column-leaching test     

Josee Duchesne Guylaine Laforest 《中国地球化学学报》2006,25(B08):99-99

Disposal of industrial solid wastes in a hydrologic environment can cause environmental risks due to the mobility of toxic trace elements. It is increasingly important to find simple and inexpensive treatments to remove undesirable elements from industrial solid wastes. One of the most important problems in the secondary steel mill industry is the disposition of dusts produced from electric arc furnace. A large quantity （10-20 kg） of electric arc furnace dust （EAFD） is generated per ton of steel produced. The Toxicity Characteristic Leaching Procedure （TCLP） shows that the total Cr and Cr （Ⅵ） concentrations （9.7 and 6.1 mg/L respectively） from the EAFD studied exceeded the Toxicity Characteristic Regulatory Level. Some heavy metals of EAFD like chromium are toxics and have high solubility. Chromium （Ⅵ） is particularly problematic because it must initially be reduced before fixed in an insoluble phase. To counter this problem, the use of ordinary Portland cement （OPC） and ground granulated blast furnace slag （GGBFS） was investigated. Column leaching test was performed to evaluate the leaching of EAFD amended with GGBFS and OPC under dynamic conditions simulating heap leaching. The goal of this study is to find a simple and economic way to decrease contaminants in the leachate. Test columns have been set up to evaluate the effect of alkaline additives （OPC and GGBFS） on the geochemistry of drainage water. The control column consists of EADF only. A set of columns presents the effect of the addition of 5% by mass of OPC or GGBFS mixed homogeneously with the EAFD. Another set of columns was set up with the same quantities of OPC and GGBFS but concentrated at the base of the EAFD simulating a liner. Columns were fed three times weakly during 1 month. The parameters monitored after each flush of water include leachate volume, pH, electrical conductance and water quality （Cr-Ni-Pb-Zn concentrations）. The leaching of the control （EAFD only） presents high Cr concentration.  相似文献   

Evaluation of ability of Rock Check Dam to prevent the transportation of Pb-contaminated sediment in Khli Ti Creek, Thailand     

Paweena Panichayapichet Suwanchai Nitisoravut Arpa Wangkiat 《中国地球化学学报》2006,25(B08):119-120

Discharge of wastewater from the retaining pond of a Pb ore-flotation plant since 1967 and breaching of the retaining pond in April 1998 contaminated 17540 cbm of river bank sediment with 833 ton Pb, nearly 19 km along the Khli Ti Creek. High blood Pb concentration was detected in many inhabitants. Prohibition of water and aquatic biota consumption has caused difficulties for rural people to make their ends meet. The governmental agency closed the ore-floatation plant and built 2 rock check dams downstream. The dam was designed to slow down water velocity and precipitate particulate matter. Contaminated sediments that have been trapped in front of the dam were planned to be dredged and disposed in landfill. Until now, no dredging is performed because some experts claim that dredging will resuspend the contaminated sediment into the water column, and fresh sediment deposited during periods of high flow will cover the contaminated sediment. The aim of this study was to evaluate the ability of the rock check dam to prevent the transportation of Pb-contaminated sediment in the Khli Ti Creek. Sediment located before and after the rock check dam and 2 km downstream were collected in September 2003 and May 2005. During September 2003, Pb concentrations in sediment deposited before and after the rock check dam and 2 km downstream were 48840, 53741 and 36020 mg/kg, respectively. These results showed that Pb-contaminated sediment was transported over the first rock check dam but still remained after the rock check dam. Result of May 2005 sampling also showed the same trend, although with different ranges due to seasonal variation, types of collected sediment, sample preparation and analytical techniques. Pb concentrations in sediment were 209684, 306775 and 33760 mg/kg, respectively.  相似文献   

Risk based management approach in contaminated land management practices     

Natalia Y. Hoogeveen 《中国地球化学学报》2006,25(B08):125-125

The present Dutch approach is often addressed in Europe as an example of practical, innovative and cost effective soil management. During the last 25 years of finding the best practices the Dutch soil clean-up policy evolved from a sectoral soil remediation program, managed and financed mainly by the central government and provinces, towards an integrated contaminated sites management approach, managed by local and regional bodies, financed by tax money and private investments. The contamination perception evolved from very strict demands on ＂full remediation＂ to the more pragmatic and practical concept of reducing or eliminating risks associated with contamination to the acceptable levels for humans and ecosystem, the so-called ＂Risk based management＂. The environmental regulatory system is presently undergoing trough considerable modifications towards integrated risk based management to satisfy the changing needs of the Dutch society and to correspond with the new European legislation as Water Framework Directive, Waster Directive and EU Soil Strategy. Dutch Policy Development, Netherlands has a long history of contaminated land management. In the year of 1979 the major obstructions for finding successful solutions for soil contamination problems were： Absence of knowledge about contamination behaviour and fate in the natural environment and as a consequence incapability to make priorities and sound decisions. Absence of experience in treating soil contamination. Not enough financial resources to clean everything according to the standards set in the legislation. During the last 25 years of finding the best practices the Dutch went through a complex process of developing realistic, affordable and practical approaches towards soil contamination. Dutch soil clean-up policy evolved from a sectoral soil remediation program,  相似文献