Effects of iron mining on surface water quality in the Schefferville area     

John J. Drake 《Applied geography (Sevenoaks, England)》1981,1(4):287-296

Iron mining in the Schefferville, Quebec, area has resulted in the disruption of some small surface drainage systems and the discharge of large amounts of pumped groundwater into them. Major ion concentrations in surface waters is controlled by the occurrence of the Denault (dolomite) formation, and little change is caused by the mining activities. Acidification of some of the waters by acid precipitation is a potential problem, but no health hazards are likely to accrue from the effects of iron mining on the surface water quality.  相似文献   

Zeus-2D Simulations of Laser-Driven Radiative Shock Experiments     

D. R. Leibrandt  R. P. Drake  J. M. Stone 《Astrophysics and Space Science》2005,298(1-2):273-276

A series of experiments is underway using the Omega laser to examine radiative shocks of astrophysical relevance. In these experiments, the laser accelerates a thin layer of low-Z material, which drives a strong shock into xenon gas. One-dimensional numerical simulations using the HYADES radiation hydrodynamics code predict that radiation cooling will cause the shocked xenon to collapse spatially, producing a thin layer of high density (i.e., a collapsed shock). Preliminary experimental results show a less opaque layer of shocked xenon than would be expected assuming that all the xenon accumulates in the layer and that the X-ray source is a pure Kα source. However, neither of these assumptions is strictly correct. Here we explore whether radial mass and/or energy transport may be significant to the dynamics of the system. We report the results of two-dimensional numerical simulations using the ZEUS-2D astrophysical fluid dynamics code. Particular attention is given to the simulation method.  相似文献   

Hydrogeology of an Alkaline Fly Ash Landfill in Eastern Iowa   总被引：1，自引：0，他引：1  

Linda Le Seur Spencer  Lon D. Drake 《Ground water》1987,25(5):519-526

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A low-cost method of reclaiming strip-mined land in Iowa to agriculture     

Lon D. Drake  G. Todd Ririe 《Environmental Geology》1981,3(5):267-279

Strippable coal in Iowa is overlain by sulfidebearing black shales capped with glacial till and loess. Weathering of these shales produces acid levels toxic to most plants, which necessitates rapid burial of the spoils. We have designed and tested a loess terrace method for returning Iowa strip mines to crop land as mining progresses. During the 1970s, corn growth and yields were monitored on various thicknesses of bess over leveled acid spoils in Mahaska County, Iowa. We evaluated the costs of reclaiming mined land to acceptable levels of productivity. When saturated loess was emplaced, the resulting compaction seriously reduced corn yields during the initial years of reclamation. This problem was substantially reduced at an adjacent site by emplacement during a dry season. After compaction had been partially alleviated by growth of sweet-clover, chisle plowing, freeze-thaw, and increase in organic matter, yields were clearly proportional to loess thickness. During years of normal rainfall, yields of approximately 100 bushels per acre were produced from about 3 1/2 feet of loess cover. Four feet of loess cover produced yields equivalent to the county average in 1978 (114 bushels/acre) and 1979 (119 bushels/acre). Although the underlying spoils were toxic (pH 3–4), upward migration of acids into the loess was minor, even during drought years. The cost of loess terrace reclamation was evaluated for 3 to 5 feet of loess cover. Assuming an average strippable coal seam thickness of 3 1/2 feet, the reclamation cost would have averaged 6.8% of the FOB price of coal during the 1970s. If the coal were trucked 50 miles to an electric utility, reclamation costs would have averaged 4.9% of the delivered price. Loess terrace reclamation would have increased the price of residential electricity by about 1%.  相似文献   

The American public’s preference for preparation for the possible effects of global warming: impact of communication strategies     

Bo MacInnis  Jon A. Krosnick  Adina Abeles  Margaret R. Caldwell  Erin Prahler  Debbie Drake Dunne 《Climatic change》2015,128(1-2):17-33

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2013年黑龙江省“三江”大洪水发生特点及启示     

那济海  潘华盛 《黑龙江气象》2013,(4):1-2,11

简叙黑龙江省2013年“三江”大洪水与1998年嫩江、松花江大洪水发生特点,在洪水来源地、致洪暴雨发生时间与地点、前期流域内降水、天气形势、赤道东太平洋海表温度、西太平洋副热带高压强度和发生时段等7方面进行了对比。在2013年洪水过后提出了6点建议：提高防洪堤坝的标准;加强黑龙江干流水库建设;加强排涝工程建设;加强对黑龙江干流水文气象监测预警工作;加强投入;加强防御自然灾害预案的实施。  相似文献   

大兴安岭扎兰屯地区四班岩体岩石成因及构造环境研究     

秦涛  李林川  唐振  江斌  钱程  孙巍  那福超  施璐 《地质力学学报》2017,23(3):369-381

大兴安岭扎兰屯地区四班岩体主要由正长花岗岩和二长花岗岩组成,内部发育细粒闪长质包体。二长花岗岩和正长花岗岩LA-ICP-MS锆石U-Pb定年结果分别为303±3Ma和291±3Ma,属于晚古生代岩浆活动的产物。四班花岗质岩石高硅(67.9~77.5 wt%)、富碱(K_2O+Na_2O=7.55~10.79 w%)、相对高铝(Al_2O_3=12.05~16.33 wt%),富集轻稀土元素(LREE)和大离子亲石元素(LILE),而亏损高场强元素(Nb、Ta、Ti和P等),属于高钾钙碱性I型花岗岩。四班花岗质岩石内部发育的闪长质微粒包体及花岗岩与其伴生的基性岩的"一锅粥"现象,表明四班花岗质岩石具有岩浆混合成因的特征,地球化学特征也支持上述观点。四班岩体显示后碰撞岩浆岩的岩石学及地球化学特征,为后碰撞阶段岩石圈地幔拆沉减薄壳幔相互作用的产物。  相似文献   

扎龙湿地火烧严重度分析及火灾对丹顶鹤生境的影响   总被引：3，自引：0，他引：3  

孔博  张树清  张柏  那晓东  李晓峰  卢晓宁 《湿地科学》2007,5(4):348-355

利用ETM 遥感影像资料,分析了扎龙湿地火烧严重度及火灾对扎龙湿地丹顶鹤(Grus japonensis)生境的影响。采用火灾前、后的ETM 影像数据,计算差异性归一化燃烧率(dNBR)和制作扎龙火烧严重度分布图,用综合燃烧指数(CBI)分析植被死亡率对生境变化的影响程度,并分析两者的相关关系;利用两种燃烧指数与对应的高程、植被类型、坡度、功能分区和丹顶鹤巢位等因子叠加分析作为火烧区的评价指标;再根据火烧严重度分类图定量化分析火灾对丹顶鹤生境和巢址变化的影响。结果表明,CBI与dNBR之间有非线性关系(n=59,R2=0.8724);判定高程在148.3~154.6m和坡度在0°~0.185°之间,且分布有大量芦苇(Phragmites australis)沼泽的核心区低洼地易发生火灾;在火烧强度较高的情况下,迫使丹顶鹤选择次适宜的栖息环境,降低了丹顶鹤对隐蔽条件和食物资源的标准,导致丹顶鹤重新选择巢址的位置,其种群数量迅速减少。研究结果对扎龙湿地动物资源可持续发展具有一定的指导意义。  相似文献   

英国矿产资源规划与战略研究          下载免费PDF全文

牛颖超  那春光 《地质论评》2022,68(6):2022112016-2022112016

英国是世界上编制矿产资源规划较早的国家之一，它的规划体系已成为许多国家尤其是英联邦国家建立规划体系的蓝本。本文通过研究英国矿产资源规划体系与管理特征，分析矿产资源发展战略，总结英国矿产资源规划的经验和启示，为我国矿产资源规划编制与管理提出建议。  相似文献