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211.
The River Lippe is situated at the northern part of the rhenish-westphalian coal mining area, Germany and has a long history of being affected by mining water discharge. There has, however, been a massive decrease in the discharge of mining water over the past few decades. While early in the last century concentrations of up to 3500 mg l−1 of chloride were observed, the mean concentration is now below 400 mg l−1. At the same time the water quality has improved greatly so factors other than chloride concentration may be influencing the macroinvertebrate community.Macroinvertebrate data collected from three sites along the River Lippe was analyzed for a change in the occurrence of salt tolerant species in an area where mining water discharge ended in 2000. It was found that also during the period of discharges the macroinvertebrate community was dominated by freshwater species and therefore the impact of mining water discharges in the upper River Lippe is considered to be minor.It was also found that for some species (Nais elinguis, Bithynia tentaculata and Gammarus tigrinus) their proposed salinity preference did not correlate with their occurrence in the field. This may be an area that requires further research.  相似文献   
212.
针对枣庄市某水泥用灰岩矿开采导致了土地挖损和压占、地形地貌景观破坏和崩塌地质灾害隐患等地质环境问题,提出了:生产过程中发现的危岩,及时予以清理,或对其进行加固;采矿结束后,开采平台外缘用浆砌毛石砌筑挡土坝,平台上部30cm覆土,下部20cm用强风化页岩做铺垫,种植侧柏,平台的内侧,按照2m的间距种植爬山虎、葛藤等攀缘类植被,绿化边坡面;露天采坑治理成人工湖等治理办法。经过恢复治理,不仅能适时地保护和恢复自然生态环境,也能有效消除矿业活动带来的地质灾害隐患;另可恢复林地及人工湖面积33.48hm2(502.2亩),具有显著的社会效益。  相似文献   
213.
根据防洪影响评价的有关规范,分析了济宁市采煤塌陷地引黄充填复垦项目对黄河河势的影响,以及黄河对项目运用的影响,就影响作出防洪综合评价,并提出有关防治措施。  相似文献   
214.
中亚五国矿业权管理与投资环境   总被引:1,自引:0,他引:1  
中亚五国矿产资源丰富,与中国有较强的互补性。近年来双方在矿产资源方面的合作不断扩大,该地区已经成为中国矿山企业"走出去"的重要选择地之一。本文就中亚五国矿业管理与投资环境进行概要的介绍和分析,为我国企业投资中亚矿业提供一定的参考。  相似文献   
215.
We present a novel methodology for integration of multiple InSAR data sets for computation of two dimensional time series of ground deformation. The proposed approach allows combination of SAR data acquired with different acquisition parameters, temporal and spatial sampling and resolution, wavelength and polarization. Produced time series have combined coverage, improved temporal resolution and lower noise level. We apply this methodology for mapping coal mining related ground subsidence and uplift in the Greater Region of Luxembourg along the French–German border. For this we processed 167 Synthetic Aperture Radar ERS-1/2 and ENVISAT images acquired between 1995 and 2009 from one ascending (track 29) and one descending (track 337) tracks and created over five hundred interferograms that were used for time series analysis. Derived vertical and east–west linear deformation rates show with remarkable precision a region of localized ground deformation located above and caused by mining and post-mining activities. Time series of ground deformation display temporal variability: reversal from subsidence to uplift and acceleration of subsidence in the vertical component, and horizontal motion toward the center of the subsidence on the east–west component. InSAR results are validated by leveling measurements collected by the French Geological Survey (BRGM) during 2006–2008. We determined that deformation rate changes are mainly caused by water level variations in the mines. Due to higher temporal and spatial resolution the proposed space-borne method detected a larger number of subsidence and uplift areas in comparison to leveling measurements restricted to annual monitoring of benchmark points along roads. We also identified one deformation region that is not precisely located above the mining sites. Comparison of InSAR measurements with the water levels measured in the mining pits suggest that part of the water that filled the galleries after termination of the dewatering systems may come from this region. Providing that enough SAR data is available, this method opens new opportunities for detecting and locating man-made and natural ground deformation signals with high temporal resolution and precision.  相似文献   
216.
外界因素是影响滑坡变形和稳定状态的重要因素。进行滑坡的稳定性分析,依据监测资料进行预警预报,都有必要考虑外界因素的作用。以云南省昆明市的金坪子滑坡为背景,运用GIS及3DSlopeGIS的三维极限平衡分析方法,从地震、库水位、降雨三个外界因素单独或复合作用下的安全系数的变化情况,研究滑坡的动态稳定性。研究表明,在外界因素的作用下,通过分析安全系数—地震烈度曲线、安全系数—库水位高度曲线以及安全系数—时间曲线,可以定量判断地震、降雨、库水位对滑坡的影响,以及三者对滑坡影响力的高低顺序,为工程的预警预报提供重要参考。  相似文献   
217.
山东省S244省道K9+500~K10+100段存在较严重的采空塌陷隐患,如何准确查清采空区的空间分布特征,对于道路的安全运营非常重要。根据以往类似工程经验,采用单一的物探方法,在准确探测采空塌陷形状、埋深等空间分布特征时存在较大难度,工程钻探可以比较直观的揭露采空塌陷的情况,但需要施工大量钻孔,在经济、时间等方面不可取,综合采用多种物探方法是一种准确有效的工作方法。以该工程为例,通过采用浅层地震反射波法和高密度电阻率法等工程物探方法,准确查明了该路段采空区空间分布特征,并通过比较直观的工程钻探对上述方法进行验证,效果良好。  相似文献   
218.
罗桂纯  胡平  王治国  王飞 《中国地震》2012,28(2):214-221
选定一块场地,针对相同井深、不同药量的情况,进行炸药震源的地震安全性野外实验,用Etna数字强震动加速度仪记录每次爆破时房屋振动的加速度.在选定房屋结构的地基、窗台、屋顶等3个位置分别布设了仪器,记录结构响应的加速度波形.为了与《爆破安全规程》的参考标准对应,将加速度值转换成速度值,并对位于屋顶的结构响应速度峰值进行分析.通过对结构响应、安全距离、频率的研究,分析建筑物结构对每次爆破的响应,并对其安全性进行讨论.  相似文献   
219.
The past 20 years have been characterised by limited interest in the economic viability of deep seabed mining with the exception of those mineral ores rich in precious metals such as polymetallic sulphides. This paper goes against the tide. After reviewing the most significant literature, it compares the economic feasibility of mining polymetallic manganese nodules and cobalt-rich ferromanganese crusts in a scenario of mutual exclusivity. It uses a new indicator, the cobalt-nickel price ratio, whose aim is to verify at what metal prices the net present value of the two mining projects equalises. Previous research has shown that the turning margin between manganese nodules and cobalt crusts is a cobalt price of $50/kg. The present paper revises this by showing that the choice between mining crust and nodules depends on fluctuations in the price of nickel. A Monte Carlo simulation proves that cobalt crust mining could be reasonably preferred to manganese nodules at cobalt prices of $40-60/kg if the price of nickel fell below $11/kg. Within this condition, investors would receive the minimum acceptable internal rate of return of 15%, which is at a level of risk closer to the land-based mining. However, when the price of nickel passes the $11/kg threshold, the equilibrium between the two ventures can be reached only at a cobalt price greater than $100/kg, causing cobalt crust to become uncompetitive. Finally, the paper, recognising that prices are not unique drivers, introduces legal, political, technological and environmental concerns to show that the final choice between the two mining ventures cannot be merely driven by economic issues.  相似文献   
220.
利用遥感技术,对兖济滕矿区2000-2010年的采煤沉陷区动态变化进行了研究,结果表明,2010年,兖济滕矿区累计沉陷面积为88.43km^2,占整个矿区面积的3.53%。10年来,沉陷区面积呈直线上升趋势,由2000年的57.37km^2,增加到2010年的88.43km^2,平均年增沉陷地面积约为3.45km^2。采用遥感手段,在大范围内,可以较直观、准确地确定采煤沉陷区的范围、面积、形态、动态变化等特征,可为沉陷区的综合治理提供科学依据。  相似文献   
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