基于灾害链效应的小秦岭乱石沟矿渣堆危险性评价     

郭付三  杜娟  周春梅 《工程地质学报》2014,22(6):1309-1315

矿产开采过程中,大规模不合理的矿渣堆弃以及高强度降雨等所引发的矿渣碎屑流,对矿山的正常生产和人员安全带来了巨大的风险。由于矿渣堆普遍沿沟谷呈串珠状分布,若下级渣堆受到上级矿渣碎屑流的冲击、加载作用,其失稳起动概率及渣流量将明显增加,这种空间逐级影响所表现出的灾害链效应是矿渣碎屑流灾害作用的重要特征。以小秦岭乱石沟为例,在对研究区内矿渣堆详细调查的基础上,首先以矿渣堆高度、坡度、方量、是否堆载振动、底床坡度以及降雨汇流累积量6项指标对矿渣堆的危险性进行评价。其次,采用UBCDFLOW方法,考虑碎屑流的路径宽度、平均坡角及流动类型,估算碎屑流的滑移距离。最后,在此基础上从风险评价与预测的角度出发,综合考虑矿渣堆碎屑流的链状逐级影响,以及下级渣堆位于上级渣堆碎屑流冲击范围内的相对位置,得到灾害链效应下的矿渣堆危险性评价。计算结果表明考虑灾害链效应后,乱石沟内受碎屑流影响的矿渣堆的破坏概率明显增加,研究结果也为矿山沟谷流域矿渣堆灾害的风险评价及防治规划设计提供依据。  相似文献   

含方解石铜矿石微生物氧化作用的实验研究     

向婉丽  陆现彩  陆昀乔  李娟  张蕊  陈笑夜  刘欢 《矿物岩石地球化学通报》2014,33(6)

矿山固体废物中硫化物经微生物作用形成的酸性矿山排水及其引起的重金属污染是备受关注的环境问题,而岩石和矿石中的方解石能够影响酸性矿山排水的生成和迁移。为了考察方解石对硫化物-微生物氧化作用的影响,开展了系统的模拟实验,利用ICP-AES、XRD、XRF等分析手段,测定了实验溶液的pH值、Eh值、离子浓度和次生沉淀成分。结果表明,在无方解石或方解石含量低时,黄铜矿的微生物氧化过程中,pH值下降、Eh值上升,有多种重金属离子进入溶液,并生成大量黄钾铁矾、自然硫等次生沉淀。添加过量方解石能有效中和氧化过程产生的酸并能显著抑制氧化菌的活动。因此通过添加碳酸盐矿物的方法可使溶液pH调节至微碱性,降低微生物的活性、阻滞铜矿石的氧化,能够有效降低重金属的释放。  相似文献   

Flood forecasts based on multi-model ensemble precipitation forecasting using a coupled atmospheric-hydrological modeling system   总被引：1，自引：0，他引：1  

Juan Wu  Guihua Lu  Zhiyong Wu 《Natural Hazards》2014,74(2):325-340

The recent improvement of numerical weather prediction (NWP) models has a strong potential for extending the lead time of precipitation and subsequent flooding. However, uncertainties inherent in precipitation outputs from NWP models are propagated into hydrological forecasts and can also be magnified by the scaling process, contributing considerable uncertainties to flood forecasts. In order to address uncertainties in flood forecasting based on single-model precipitation forecasting, a coupled atmospheric-hydrological modeling system based on multi-model ensemble precipitation forecasting is implemented in a configuration for two episodes of intense precipitation affecting the Wangjiaba sub-region in Huaihe River Basin, China. The present study aimed at comparing high-resolution limited-area meteorological model Canadian regional mesoscale compressible community model (MC2) with the multiple linear regression integrated forecast (MLRF), covering short and medium range. The former is a single-model approach; while the latter one is based on NWP models [(MC2, global environmental multiscale model (GEM), T213L31 global spectral model (T213)] integrating by a multiple linear regression method. Both MC2 and MLRF are coupled with Chinese National Flood Forecasting System (NFFS), MC2-NFFS and MLRF-NFFS, to simulate the discharge of the Wangjiaba sub-basin. The evaluation of the flood forecasts is performed both from a meteorological perspective and in terms of discharge prediction. The encouraging results obtained in this study demonstrate that the coupled system based on multi-model ensemble precipitation forecasting has a promising potential of increasing discharge accuracy and modeling stability in terms of precipitation amount and timing, along with reducing uncertainties in flood forecasts and models. Moreover, the precipitation distribution of MC2 is more problematic in finer temporal and spatial scales, even for the high resolution simulation, which requests further research on storm-scale data assimilation, sub-grid-scale parameterization of clouds and other small-scale atmospheric dynamics.  相似文献   

Characterization of Colliery Spoils in León: Potential Uses in Rural Infrastructures     

Joaquín Ferreras Cadierno  Manuel Ignacio Guerra Romero  Andrés Juan Valdés  Julia Mª Morán del Pozo  Julia García González  Desirée Rodríguez Robles  José Vallepuga Espinosa 《Geotechnical and Geological Engineering》2014,32(2):439-452

One of the bases of sustainable development is the responsible management of natural resources, and this is the approach which has been adopted by developed countries as regards management of all kinds of waste, through the establishment of management strategies based on prevention, reuse and recycling. This article present the results of a physical, chemical and geotechnical characterization of colliery spoils stored in slag heaps in the Ciñera-Matallana coal mining area in León, Spain. The primary objectives of this research were to determine the suitability of this mining waste for use as granular material in rural and civil engineering infrastructures and to classify it according to national and international road construction standards. On the basis of the results obtained, they are proposed several possible uses (foundation and core layers in track and road embankments, granular sub-base for light traffic and top layers of embankments), although it should be noted the need for mechanical treatments as crushing or sieving and the recommendation of use of sulphate resistant cement to avoid the possible problems.  相似文献   

三峡库区巴东地震(M_s5.1)成因机制及次声波信号          下载免费PDF全文

李献瑞  曾佐勋  周强  贺赤诚  刘江平  赵娟  潘黎黎 《地球科学》2014,39(12):1793-1806

2013年12月16日三峡库区巴东发生M_s5.1地震.根据eigen-6c2模型研究了巴东地区的8-638阶卫星重力异常, 结果表明: 该地区场源深度为10 km的地壳为局部重力低异常, 反映了该处物质密度较周围偏低, 形成低密度层.同时, 研究了该地区速度结构剖面, 结果表明: 巴东地区地壳5~9 km及10~15 km深处存在上下两个低速层, 上部低速层与水库渗水有关, 下部低速层与地幔热流体的上涌有关.低密度层和低速层的确定为韧性流变层的存在提供了证据.巴东地震是地壳深部能量的长期集聚与突发释放, 属构造地震.然而, 库水下渗引起的上部低速异常降低了断层活动的阈值, 震前库水载荷的变化对此次巴东地震的发生起到了触发作用.通过对比次声波和地震波, 我们得出次声波仪记录到的异常信号为本地次声波.   相似文献   

基于单片机技术的钻井液流量异常报警器          下载免费PDF全文

吕万宏  尹丹  王娟  辛志相  张成志 《探矿工程》2014,41(1):63-65，69

钻井液在钻进过程中起着至关重要的作用,进入钻孔的钻井液量的异常容易引发烧钻、埋钻等孔内事故。介绍了一种基于单片机技术的钻井液流量异常报警装置。  相似文献   

Benthic microbial biogeography along the continental shelf shaped by substrates from the Changjiang River plume     

Yongjun Wei  Shan Jiang  Lingmin Tian  Liping Wei  Jie Jin  Juan Severino Pino Ibanhez  Yan Chang  Xiaodao Wei  Ying Wu 《海洋学报(英文版)》2022,41(1):118-131

Coastal zones are active reactors of continental material including that transported by rivers via a series of microbiota-mediated reactions. Nevertheless, current knowledge of the ecology and functioning of the microbiota in coastal areas affected by large riverine inputs remains insufficient on a global scale. Here, an investigation on sediment microbial composition, including taxonomy and metabolic network, as well as their relationship with major benthic reaction substrates, namely carbon, n...  相似文献   

近20a察尔汗盐湖区景观格局变化与趋势分析          下载免费PDF全文

陈亮  王建萍  韩进军  王二龙  张娟  王罗海 《盐湖研究》2022,30(2):19-26

柴达木盆地主要景观类型为干盐湖和盐渍地,为了解区内各类景观类型空间分布特征、景观类型变化转移矩阵及变化趋势,分别选取了2000年、2010年、2020年作为3个关键研究时段,以Landsat TM多光谱卫星遥感数据为数据源,采用水体指数法与目视解译相结合的方法,建立了七类遥感图像解译标志,对近20a察尔汗盐湖区景观格局变化进行了分析。结果表明:察尔汗湖区的工矿用地面积、盐田面积、人工湿地(水库)面积在2000~2020年呈现出明显增加的趋势,而盐湖和干盐湖的面积呈现出明显减少的趋势;2000年以后,人工湿地(水库)的面积逐年增长达到了218.88 km²,在以盐滩戈壁为主的原生环境比较恶劣的盐湖区内,这片新生水域为当地野生动植物提供了十分宝贵的生境场所。  相似文献   

Assessment of FY-4A and Himawari-8 Cloud Top Height Retrievalthrough Comparison with Ground-Based MillimeterRadar at Sites in Tibet and Beijing     

Bo LIU  Juan HUO  Daren LYU  Xin WANG 《大气科学进展》2021,38(8):1334-1350

正1Key Laboratory of Middle Atmosphere and Global Environment Observation, Institute of Atmospheric Physics,Chinese Academy of Sciences, Beijing 100029, China2University of Chinese Academy of Sciences, Beijing 100049, China  相似文献   

Magnetostratigraphy and environmental magnetism in a Pleistocene sedimentary sequence, Marcos Paz, Argentina     

Juan Carlos Bidegain  S. Jurado  M. A. E. Chaparro  M. Gómez Samus  S. Zicarelli  A. V. Parodi 《Environmental Earth Sciences》2013,68(3):749-763

The deterioration of groundwater quality, particularly due to salinization, because of the overexploitation of groundwater in the Lower Central Plain of Thailand remains a major concern. With increasing demand for water there is a growing need for sustainable management of the resource, which would benefit from an improved understanding of the sources of chloride contamination. Thus, a hydrochemical and isotopic study was carried out to chemically characterize groundwater and to investigate possible sources of salinization, and in particular of chloride contamination, in the multi-layered Bangkok aquifer system. Groundwater samples were taken from four topmost aquifers (Bangkok, Phra Pradaeng, Nakhon Luang, and Nonthaburi). Additionally, short-term rainwater sampling, as well as river and seawater sampling was performed and later analyzed for ionic composition and stable water isotopes. Ionic and isotopic data indicate at least three different recharge sources for groundwater. The major recharge source is rainwater. The influence of seawater is limited to the coastal region and tidally influenced areas of the two main rivers (Chao Phraya and Tha Chin). Bromide data also suggest the influence of saline water in deeper aquifers due to trapped water. Most importantly, although the influence of seawater on groundwater is recognizable, the surrounding geology contributes a significant number of dissolved ions detected in the groundwater.  相似文献