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1.
以往的三维地质图由于多是仅利用数字高程模型（DEM）对平面地质图进行z轴方向的扩展,并不包含真三维的属性信息和空间信息,因此其在空间查询、分析和决策方面表现出明显的局限性。笔者首先分析总结了地上地下空间数据和现有数据模型的特点;然后使用UML建模工具建立了基于Geodatabase的地上-地下、地质-地理、属性-空间一体化的数据库模型,在此基础上设计了地上地下一体化的数据库原型,并借鉴地上地下集成建模的思想,探讨了在ArcGIS Engine环境中进行三维地质图编绘的思路和方法,实现了具有空间查询、分析等真三维特征的地质图的编绘;最后研发了相应的系统原型对该方法进行了实例验证。结果表明：地上地下集成建模可以解决地上地下三维模型的无缝集成问题,以空间集成的方式进行三维地质图的编绘具有一定的可行性和实用性。 相似文献
2.
A model for the assessment of aquifer contamination potential based on regional geologic framework 总被引：2，自引：0，他引：2
The texture and three-dimensional framework of geologic materials should be considered in assessments of groundwater's vulnerability to contamination because geology controls the movement of contaminants and groundwater and influences groundwater quality. Contaminants are introduced into, transmitted through, and stored by geologic materials. We present a model that identifies aquifers and ranks sequences of geologic materials by their relative potential for transmitting water and contaminants from land surface. With this basis, the model can be used to assess the potential for contamination of aquifers by surface activities such as landfitling of wastes or application of agricultural chemicals. A regional map of aquifer contamination potential can be generated from the model; it retains the geologic map information intact and available for reinterpretation or other uses.The model was developed using broad, regional map information and is intended to be a general tool for assessing the regional vulnerability of aquifers to contamination. It is not intended for local, site-specific use, but for prioritizing local areas where contamination potential and/or land-use history warrant more detailed assessment or monitoring. Because it provides a regional view of contamination potential, regional patterns or trends of map units should be evaluated, rather than using the map information literally to assess local areas. Methods of applying this model and contamination potential map to groundwater protection and management are currently being studied; research includes an attempt to statistically validate the model with water-quality data, and to identify natural groupings of the ranked contamination potential map units. 相似文献
3.
为了提高电阻率法对地下介质污染问题的探测能力,分析了含油污水污染地下介质后引起的导电性变化,建立了适用于该问题分析的地电模型。利用2.5维有限元的方法正演模拟了采用温纳、施龙贝格、偶极和二极装置监测时所得的典型电异常剖面。正演模拟结果显示不同装置对污染区的反映能力不同,相对而言施龙贝格和温纳装置对污染区分布的反映较为直观。饱和粘土的含油污染区用温纳装置测量,剖面上表现为相对高阻异常特征,异常区域分布和污染通道相吻合。应用实例也证实了这一分析。 相似文献
4.
污染造成的环境损害和土壤与地下水质量降低,直接影响生命健康与环境安全。污染企业搬迁后遗留场地的调查检测与修复治理,是土地资源开发利用与管理的重要环节。结合两个炼油厂污染地块在土地再开发期间所进行的土壤环境调查和治理修复案例,阐述了石油类污染地基土的环境调查方法、评价方式和治理修复措施,以期为污染土壤的调查与治理修复提供借鉴。 相似文献
5.
在物探工作设计阶段,主要参考测区的地质图和地形图,进行控制点的选取和测网的布置.但这些地形图往往是七十年代、八十年代绘制的,随着自然环境的变化,人类活动的改造,可能发生了很大的变化,如湖泊水位变化,居民点变迁、城市的扩建、地质灾害等.随着"3S"集成技术的不断成熟,可以利用带地理参数的遥感影像对地形图的变更部份进行修正... 相似文献
6.
This study examines linear spectral unmixing technique for mapping the surface soil types using field spectroscopy data as the reference spectra. The investigated area is located in North Sinai, Egypt. The study employed data from the Landsat 7 ETM+ satellite sensor with improved spatial and spectral resolution. Mixed remotely sensed image pixels may lead to inaccurate classification results in most conventional image classification algorithms. Spectral unmixing may solve this problem by resolving those into separate components. Four soil type end-members were identified with minimum noise fraction and pixel purity index analyses. The identified soil types are calcareous soils, dry sabkhas, wet sabkhas, and sand dunes. Soil end-member reference spectra were collected in the field using an ASD FieldSpec Pro spectrometer. Constrained sum-to-one and non-negativity linear spectral unmixing model was applied and the soil types map was produced. The results showed that linear spectral unmixing model can be a useful tool for mapping soil types from ETM+ images. 相似文献
7.
为查明场地污染分布特征,需对场地土壤和地下水进行钻探取样,按规范的检测指标进行逐一测试。在初查和详查阶段将获得大量的土壤和地下水污染数据,数据样本数量大、监测指标多,数据结构复杂,如何从场地大数据中提取价值信息已成为研究热点。以某有机污染场地为例,基于自组织映射神经网络（SOM）和K均值算法开展大数据分析,深入探讨地下水和土壤中各污染指标间的相关性。结果表明:（1）基于自组织映射神经网络的大数据分析可快速挖掘复杂多维的污染场地监测数据,有效完成关键信息的提取;（2）地下水中污染检出指标存在显著的聚类特征,同一聚类中的污染指标具备相似的空间分布特征。对场地污染物检测采取先分类后分级的优化筛选策略,减少污染物检测指标数目,从而有效降低场地检测费用;（3）土壤和地下水中污染检出指标存在良好的空间相关性,这与该污染场地地下水渗流速度缓慢有关。土壤和地下水污染检出指标空间分布的相关性,有助于场地污染源的追溯。 相似文献
8.
In the present study, an attempt was made to delineate soil contamination around the ash pond of a coal-based thermal power plant. The topsoil in the study area was found to be contaminated to varying degrees from ash disposal. The soil drawn from various profiles was largely contaminated by ash fall out, predominantly in the prevalent wind direction. Pb, Zn, Cu, Ni, Co, Mn, Cr, V and Ba were found to be enriched in the topsoil around the ash pond with respect to the crust as well as the background, while Mn, V, Cr, Co and Ni were enriched compared to their maximum permissible concentrations prescribed for agricultural soils. These observations have been further strengthened from the contamination index map and lognormal distribution pattern of the elements. As a consequence of this contamination, many of the important physicochemical properties of topsoil in the direction of the wind have been modified significantly.Electronic Supplementary Material Supplementary material is available in the online version of this article at 相似文献
9.
This paper proposes an approach to extend a modified hardening soil model into the time-dependent analysis of high rockfill dams. The key feature of the extended model is the integration of a creep model and the double yield surface elasto-plastic model, via modifying the hardening functions. The integrated model is validated by a laboratory multistage creep test. Results from three-dimensional analyses including the without creep and with creep considerations of the Nam Ngum 2 dam have been compared with the in-situ measurements. The prediction of dam deformation can be significantly enhanced by the proposed model. 相似文献
10.
Sustainable mineral resources management: from regional mineral resources exploration to spatial contamination risk assessment of mining 总被引：3，自引：0，他引：3
Wide-spread environmental contamination associated with historic mining in Europe has triggered social responses to improve
related environmental legislation, the environmental assessment and management methods for the mining industry. Mining has
some unique features such as natural background contamination associated with mineral deposits, industrial activities and
contamination in the three-dimensional subsurface space, problem of long-term remediation after mine closure, problem of secondary
contaminated areas around mine sites, land use conflicts and abandoned mines. These problems require special tools to address
the complexity of the environmental problems of mining-related contamination. The objective of this paper is to show how regional
mineral resources mapping has developed into the spatial contamination risk assessment of mining and how geological knowledge
can be transferred to environmental assessment of mines. The paper provides a state-of-the-art review of the spatial mine
inventory, hazard, impact and risk assessment and ranking methods developed by national and international efforts in Europe.
It is concluded that geological knowledge on mineral resources exploration is essential and should be used for the environmental
contamination assessment of mines. Also, sufficient methodological experience, knowledge and documented results are available,
but harmonisation of these methods is still required for the efficient spatial environmental assessment of mine contamination. 相似文献
11.
Selective extraction procedures applied to geochemical prospecting in an area contaminated by old mine workings 总被引：1，自引：0，他引：1
F. Sondag 《Journal of Geochemical Exploration》1981,15(1-3)
A geochemical soil survey in the vicinity of the known ore body at Lontzen (Belgium) revealed numerous lead and/or zinc anomalies. Three soil traverses were selected in this area and examined for possible contamination. Two anomalous samples from one traverse were obviously contaminated (brick fragments). A sequential selective extraction procedure was applied to the soil samples, using a modification of the method of Gatehouse et al.Using this procedure, lead anomalies related to the probable extension of a known galena-sphalerite vein appear in every dissolution step. In contrast, in contaminated samples, only the final acid digestion produced anomalous values. One may thus suppose that contamination of the sample adds metal in the form of a resistant phase which is only dissolved by strong acid reagents. It should be noted that the contrast between anomalous and background values is highest for hydroxylamine hydrochloride and about the same for all other dissolution steps.The samples were also submitted to non-sequential selective extractions. The calculation of the difference between non-sequential and sequential extractions leads to the localization of two highly contrasted peaks which correspond exactly with the ore veins. 相似文献
12.
13.
土中石油污染物具有不稳定性,随环境改变易向周边发生二次迁移,危及周围土体和水体。本文以滨海地区石油污染盐渍土为研究背景,考虑污染强度、石油污染物在土中的存留时间、土体密度为变量参数,探索即时淋滤和过时淋滤条件下土中石油污染物的二维向迁移规律。研究结果表明:即时淋滤条件下,石油污染物强度越大,其在盐渍土中迁移的越深,最大迁移深度为6 cm。干密度（1.2~1.4g ·cm-3）对盐渍土中石油污染物迁移深度的影响较小,但干密度越大,土体对石油污染物的截留能力越强,相同深度处石油污染物的浓度越低。在水平方向,污染强度越大,密度越大,石油污染物在土体中沿半径方向浓度递减幅度越大;过时淋滤条件下,石油污染物在竖直方向的迁移规律与即时条件下相似,但表层盐渍土对石油的截留能力更强,其在盐渍土中迁移的最大深度为4 cm,土体对石油类污染物的最大截留率为99.98%。在水平方向,污染强度越大,密度越小,石油污染物在土体中沿半径方向浓度递减幅度越大;盐渍土对石油污染物具有一定的吸附性,增大密度有利于提高吸附的稳定性。 相似文献
14.
轻非水相流体(LNAPL)泄漏后会对土壤和地下水造成严重污染,为了准确探测出LNAPL泄漏范围,本文将GPR天线-目标极化的瞬时属性分析方法应用于轻非水相流体污染土壤探测的研究中。采用注入柴油的石英砂砂箱在实验室建立污染土壤模型,利用探地雷达对该污染土壤分别进行天线方位为0°、90°的测量。LNAPL土壤污染物形状、大小、结构并不规则,因此可以通过0°和90°方位天线测量来分析天线-目标极化特征,了解目标物的走向、形状等地下介质信息。通过对预处理后的包含天线-目标极化特征的信息进行瞬时属性分析,LNAPL污染范围可以被清晰地识别,提高了GPR探测能力。 相似文献
15.
Sang-Hwan Lee Wonhyun Ji Hun-Jae Yang Se-Yeong Kang Dae Moon Kang 《Environmental Earth Sciences》2017,76(20):720
The environmental issues associated with mining have damaged the industry’s substantial global economic value. In particular, the mining industry has a negative legacy of contaminated land. The effective reclamation of contaminated soil is therefore required before former mining land can be further developed for residential and commercial purposes. The objective of this study was to technically evaluate the feasibility of reclamation techniques for agricultural soils contaminated with toxic elements (As, Cd, Cu, Pb, and Zn) associated with metal mining. The reclamation methods investigated were covering without stabilization, covering with stabilization, and exchange with stabilization. The thickness of the soil layer used in covering and exchange was in the range of 30–50 cm. Limestone, furnace slag, and a mixture of limestone and furnace slag were applied as soil amendments. After reclamation, the contamination level in surface tillage soils and crops was monitored regularly. Four years of monitoring data revealed that surface soil contamination levels could be maintained at acceptable levels, although at some sites, the metal levels in crops exceeded legislative limits. Soil reclamation at former mining sites in Korea has not yet been perfected, but the results of this study show that there is potential for safe agricultural operations on large sites in a cost-effective manner, as long as the appropriate control of surface soil contamination and adequate agronomic management is undertaken. 相似文献
16.
Alessandro Amorosi Irene Sammartino Giovanni Sarti 《Environmental Earth Sciences》2013,69(5):1661-1671
Identification of reliable background values of potentially toxic metals in sediments requires detailed integration of geochemical data with accurate sedimentological studies. Through analysis of 60 soil samples from the Pisa coastal plain, this study shows to what extent sediment provenance and facies characteristics may influence the natural distribution of potentially toxic metals (Cr, Ni, Cu, Zn, Pb) within alluvial and coastal sediments. Metals supplied to the alluvial plain are mostly concentrated within the finest sediment fraction (floodplain clays), while coarser crevasse and overbank deposits exhibit invariably lower metal contents. Beach-ridge sands display the lowest metal concentrations. Transport of ophiolitic detritus by the longshore drift may account for locally high Cr concentrations within beach deposits. Geochemical fingerprinting of individual facies associations in terms of natural metal contents results in the construction of a geologically-based geochemical map. This map offers a more reliable depiction of spatial distribution of background levels than interpolation techniques based uniquely upon statistical methods. Matching background values against metal concentrations from topsoil samples leads to the reliable assessment of the pollution status of Pisa coastal plain. Metal contents exceeding the threshold values designated for contaminated areas (Cr) simply reflect catchment geology, and are not the product of artificial contamination. On the other hand, anthropogenic disturbance may be detected even where metal contents (Pb, Cu) lie below the threshold values. The use of sedimentological criteria is presented here as a pragmatic tool to enhance predictability of natural metal contents in sediments, with obvious positive feedbacks for legislative purposes and environmental protection. 相似文献
17.
Groundwater vulnerability assessment in shallow aquifer of Kathmandu Valley using GIS-based DRASTIC model 总被引：1，自引：0，他引：1
Dhundi Raj Pathak Akira Hiratsuka Isao Awata Luonan Chen 《Environmental Geology》2009,57(7):1569-1578
In this paper, groundwater aquifer vulnerability map has been developed by incorporating the major geological and hydro-geological
factors that affect and control the groundwater contamination using GIS based DRASTIC model. This work demonstrates the potential
of GIS to derive a map by overlying various spatially referenced digital data layers that portrays cumulative aquifer sensitivity
ratings across the Kathmandu Valley, Nepal, providing a relative indication of groundwater vulnerability to contamination.
In fact, the groundwater is the major natural resources in Kathmandu for drinking purpose. The decline in groundwater levels
due to the over exploitation and thus extracted water from shallow aquifer has been contaminated by the infiltration of pollutants
from polluted river and land surface is continuous and serious. As the demand for water for human and industrial use has escalated
and at the same time, the engineering and environmental costs are much higher for new water supplies than maintaining the
existing sources already in use. Management of groundwater source and protecting its quality is therefore essential to increase
efficient use of existing water supplies. Aquifer vulnerability maps developed in this study are valuable tools for environmental
planning and predictive groundwater management. Further, a sensitivity analysis has been performed to evaluate the influence
of single parameters on aquifer vulnerability assessment such that some subjectivity can be reduced to some extent and then
new weights have been computed for each DRASTIC parameters. 相似文献
18.
Determination of the origin of heavy metals in the household dust and street sediment in a previously heavily contaminated
area was carried out. The main question addressed was the origin of heavy metals in dry and wet air deposits measured in the
environmental monitoring programme of the community of Celje. There are two possible sources: present atmospheric emissions
by industries in Celje and dusting of previously heavily contaminated soil. Determination of the present emissions was done
on the basis of a method based on enrichment factor calculations. Samples of soil, street sediment and household dust in the
contaminated area and in a non-contaminated sampling point were analysed. Expected heavy metal concentrations in household
dust and street sediment in the previously heavily polluted area according to the level of measured soil contamination were
calculated. Expected and measured values were compared to detect possible present atmospheric emissions. The data show higher
enrichment with elements related to ironworking activities (Fe, Co, Cr, Mn, Ni) in household dust and street sediment, according
to the concentrations in the soil in the vicinity of ironworks in comparison to the reference point. Similar observations
can be made at the sampling point, east of a factory producing TiO2-based white pigment for Ti, because emissions from it are expected. In contrast, the same trend is not observed for elements
related to pollution problems in Celje (Cd, Zn, Pb). This indicated that street sediment and household dust might be a good
tracer of present atmospheric emissions, despite the fact that the environment was previously highly contaminated. The method
yields good results, which fit very well with expectations. 相似文献
19.
The curve number (CN) is a hydrologic parameter used to describe the stormwater runoff potential for drainage areas, and it is a function of land use, soil type, and soil moisture. This study was conducted to estimate the potential runoff coefficient (PRC) using geographic information system (GIS) based on the area’s hydrologic soil group, land use, and slope and to determine the runoff volume. The soil map for the study area was developed using GPS data carried on to identify the soil texture to be used in building a soil hydrological groups map. Unsupervised and supervised classifications were done to Landsat 5/7 TM/ETM image to generate land-use and land-cover map. This map was reclassified into four main classes (forest, grass and shrub, cropland, and bare soil). Slope map for Al-Baha was generated from a 30-m digital elevation model. The GIS technique was used to combine the previous three maps into one map to generate PRC map. Annual runoff depth is derived based on the annual rainfall surplus and runoff coefficient per pixel using raster calculator tool in ArcGIS. An indication that in the absence of reliable ground measurements of rainfall product, it can satisfactorily be applied to estimate the spatial rainfall distribution based on values of R and R 2 (0.9998) obtained. Annual runoff generation from the study area ranged from 0 to 82 % of the total rainfall. Rainfall distribution in the study area shows the wise use of identifying suitable sites for rainwater harvesting, where most of the constructed dams are located in the higher rainfall areas. 相似文献
20.
为了更好地与生态环境及灾害地质紧密结合,第二代全国区域地质志编制项目规定第四纪地质及地貌图为必编图件之一。图件内容包括第四纪地质体的时代、成因类型、岩性和地貌成因形态组合类型、活动断裂及海侵范围等重要地质内容,同时,附第四纪地质-地貌典型剖面和重要的地貌景点。图件特点:(1)图件的地理底图是首次用数字高程模型(DEM)数据灰度图作背景;(2)第四纪地质内容与地貌成因形态类型同编为一幅图;(3)第四纪地质体的面色用成因类型色表示;(4)地貌部分划分了不同级别成因形态类型和有特色的微地貌景点。总之,图面有立体感,地形高差明显,层次分明,色彩鲜艳,是一幅崭新的图件,可供防灾治理和地质旅游参考应用。 相似文献