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991.
992.
由中国地质调查局组织研制的《三维地质模型数据交换格式》已制定完毕,并进行了一定范围的试用,即将发布实施,这是中国区域地质调查、矿产资源勘探以及数字矿山界的一件大事,它将促进三维地质建模技术在我国的广泛应用。通过研究与试用,阐述了对该标准的理解;给出其在三维地质建模中的应用实例,包括三维地质填图试点项目、矿产资源勘探项目;讨论了该标准的数据与数字矿山常用的DXF转换的必要性与具体实现方法。将该标准与国际地球科学联合会(IUGS)及开放地理信息联盟(OGC)制定的GeoSciML进行比较,指出Geo3DML是面向三维地质模型的表达,而GeoSciML以前的版本则侧重于互联网环境下传统的二维地质图件的地图服务与要素服务。最后对该标准的应用实施提出了8点建议:给Geo3DML以应用机会,将Geo3DML升级为国家标准,对Geo3DML补充一些细节,向相关行业宣传Geo3DML,在地质调查与矿山资源勘探项目中积极使用Geo3DML,将Geo3DML作为地质报告评审中三维地质模型的数据格式,三维地质建模软件厂商积极支持Geo3DML,数字矿山软件与Geo3DML接轨。 相似文献
993.
基于证据权法的赣南稀土矿山地质环境评价 总被引:1,自引:0,他引:1
为了解决矿山地质环境评价研究中指标权值计算和评价分级具有较大主观性的问题,本文发展了一种基于证据权法的矿山地质环境评价模式,利用GIS的空间分析功能,提取矿产开发活动、坡度、坡向、高程、构造、植被覆盖度6类地质环境评价指标,运用证据权法计算指标权值。结合条件独立性检验结果,优选评价指标并计算后验概率。采用后验概率面积频率法对赣南稀土矿山地质环境进行综合评价分级。结果表明,研究区内地质环境差区域主要分布在其东南部和西部;矿产开发活动是影响研究区内地质环境质量最主要的因素。采用效率曲线法对模型验证,正确率和预测率分别为90.1%和89.5%。证据权法能够有效避免主观因素干扰,评价结果客观,具有可重现性,适用于矿山地质环境质量评价。 相似文献
994.
995.
The pH is one of the major chemical parameters affecting the results of remediation programs carried out at abandoned mines and dumps and one of the major parameters controlling heavy metal mobilization and speciation. This study is concerned with testing the feasibility of estimating surface pH on the basis of airborne hyperspectral (HS) data (HyMap). The work was carried on the Sokolov lignite mine, as it represents a site with extreme material heterogeneity and high pH gradients. First, a geochemical conceptual model of the site was defined. Pyrite, jarosite or lignite were the diagnostic minerals of very low pH (<3.0), jarosite in association with goethite indicated increased pH (3.0–6.5) and goethite alone characterized nearly neutral or higher pH (>6.5). It was found that these minerals have absorption feature parameters which are common for both forms, individual minerals as well as parts of the mixtures, while the shift to longer wavelengths of the absorption maximum centered between 0.90 and 1.00 μm is the main parameter that allows differentiation among the ferric minerals. The multi range spectral feature fitting (MRSFF) technique was employed to map the defined end-members indicating certain pH ranges in the HS image datasets. This technique was found to be sensitive enough to assess differences in the desired spectral parameters (e.g., absorption shape, depth and indirectly maximum absorption wavelength position). Furthermore, the regression model using the fit images, the results of MRSFF, as inputs was constructed (R2 = 0.61, Rv2 = 0.76) to estimate the surface pH. This study represents one of the few approaches employing image spectroscopy for quantitative pH modeling in a mining environment and the achieved results demonstrate the potential application of hyperspectral remote sensing as an efficient method for environmental monitoring. 相似文献
996.
基于国产卫星数据的矿山遥感监测一体化解决方案——以西藏自治区为例 总被引:1,自引:0,他引:1
随着高分辨率国产遥感卫星数据的推广应用,矿山遥感监测必将成为该数据的重要应用领域之一。结合西藏自治区矿山遥感监测工作的特点,以资源一号02C(ZY-1 02C)及高分一号(GF-1)卫星影像为数据源,在ArcGIS环境下,提出并实现了从国产卫星遥感数据管理、增强与校正、信息提取、统计分析以及成果图制作等一体化解决方案。该研究成果有助于推进国产卫星遥感数据在矿山遥感监测领域的应用广度和深度,为大规模开展多期次动态矿山遥感监测工作提供技术支持和应用范例。 相似文献
997.
998.
Masayuki Sakakibara Yuko Ohmori Nguyen Thi Hoang Ha Sakae Sano Koichiro Sera 《洁净——土壤、空气、水》2011,39(8):735-741
Phytoremediation is an environmental remediation technique that takes advantage of plant physiology and metabolism. The unique property of heavy metal hyperaccumulation by the macrophyte Eleocharis acicularis is of great significance in the phytoremediation of water and sediments contaminated by heavy metals at mine sites. In this study, a field cultivation experiment was performed to examine the applicability of E. acicularis to the remediation of water contaminated by heavy metals. The highest concentrations of heavy metals in the shoots of E. acicularis were 20 200 mg Cu/kg, 14 200 mg Zn/kg, 1740 mg As/kg, 894 mg Pb/kg, and 239 mg Cd/kg. The concentrations of Cu, Zn, As, Cd, and Pb in the shoots correlate with their concentrations in the soil in a log‐linear fashion. The bioconcentration factor for these elements decreases log‐linearly with increasing concentration in the soil. The results indicate the ability of E. acicularis to hyperaccumulate Cu, Zn, As, and Cd under natural conditions, making it a good candidate species for the phytoremediation of water contaminated by heavy metals. 相似文献
999.
电感耦合等离子体发射光谱法同时测定铅锌矿中银铜铅锌 总被引:4,自引:3,他引:1
采用盐酸-硝酸-硫酸混合酸分解样品,全谱直读电感耦合等离子体发射光谱法同时测定铅锌矿石中的银、铜、铅和锌。基于改善和提高测定结果准确度和精密度的要求,分析了溶液稀释因子和酸度等实验条件对测定结果的影响。结果表明,当溶液的稀释因子为1000,盐酸的体积分数在5%~10%时,测定结果最佳。采用内标法,通过加入钴内标测量分析谱线的相对强度,抵消了由于实验条件的波动引起的影响。方法检出限银为1.96μg/g,铜为6.00μg/g,铅为9.00μg/g,锌为3.00μg/g,精密度(RSD,n=10)为1.41%~7.50%。方法经国家标准物质分析验证,测定值与标准值相符,结果准确可靠。 相似文献
1000.
In the initial period of mining activities in the Idrija basin (the16th and the first half of the17th centuries), Hg ore processing was performed at various small-scale roasting sites in the woods surrounding Idrija, by roasting ore in earthen vessels. The recovery rate of this method was very low; about half of Hg was lost, causing soil contamination and considerable amounts of waste material that could potentially leach Hg into the surrounding environment. The main aims of present geochemical study were to determine the contents, vertical distribution and speciation of Hg in soils at the roasting site at Frbej?ene trate in order to verify the extreme pollution of ancient Hg ore roasting sites in the Idrija area and to establish their significance in the wider spatial contamination of soils and aquatic systems. Soil sampling was performed at the area of the former roasting site. The organic matter-rich surface soil layer (SOM) and underlying mineral soil were sampled at 63 sampling locations. Mercury speciation was performed using Hg thermo-desorption-AAS to distinguish cinnabar from potentially bioavailable forms. The results indicate extremely high Hg concentrations with a maximum of 37,000 mg/kg in SOM and 19,900 mg/kg in mineral soil. The established Hg median in soil was 370 mg/kg and in SOM 96.3 mg/kg. Spatial distributions of Hg in SOM and soil showed very high Hg contents in the central area and decreased rapidly with distance. The results of Hg thermo-desorption measurements indicated the presence of cinnabar (HgS) and Hg bound to organic or mineral soil matter. A significant portion (35–40%) of Hg in the investigated soil and SOM samples was comprised of non-cinnabar compounds, which are potentially bioavailable. It has been shown that soils contain high amounts of potentially transformable non-cinnabar Hg, which is available for surface leaching and runoff into the surrounding environment. Therefore, contaminated soils and roasted residues at the studied area are important for persistent Hg release into the aquatic ecosystem. 相似文献