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1.
苏锡常地区浅层地下水开发利用前景分析 总被引：5，自引：1，他引：5
针对以往苏锡常地区浅层地下水开发利用所面临的一系列问题,本文通过选择典型地段进行浅层地下水开采试验工作,从浅层地下水的水质、水量以及所采取的开采工艺等几个方面论证了浅层地下水开采的可行性,分析了苏锡常地区浅层地下水的开发利用前景。 相似文献
2.
开采浅层地下水对地面沉降影响的探讨 总被引：5，自引：0，他引：5
苏锡常地区由于长期过量开采深层地下水，已诱发了严重的地面沉降灾害。为此，江苏省政府下达了在2005年全面禁采深层地下水的文件。为解决用水问题，许多专家、学者建议开采利用浅层地下水。在苏锡常地区开采浅层地下水是否会同样诱发严重的地面沉降问题，是目前争议的焦点。文章详述了苏锡常地区水文地质条件及地面沉降现状，确定了地面沉降的各种影响因素，分析对比了浅层地下水与深层地下水在开采条件下所能引起的地面沉降量，说明采用合理的开采工艺开发利用浅层地下水不会诱发严重的地面沉降。 相似文献
3.
苏锡常地区是我国经济最发达的地区之一。多年来，该地区由于超量开采深层地下水已经引起了严重的地质灾害。在当前严禁开采深层地下水的形势下，对该地区的浅层地下水资源进行科学评价，查明该地区浅层地下水的开发潜力具有十分重要的意义。本文采用GMS软件对常州市滆湖典型地块浅层地下水进行了精细的数值模拟，经模型识别和校正之后，对典型地块的浅层地下水可开采量做出评价。本次对浅层地下水的数值模拟在苏锡常地区内尚属首次，模拟结果可为今后全区合理开发利用浅层微承压地下水提供依据。 相似文献
4.
基于同位素与水化学分析法的地下水补径排研究——以苏锡常地区浅层地下水为例 总被引：2，自引：1，他引：1
在分析研究区浅层地下水空间分布特征的基础上,采用同位素与化学分析相结合的方法研究苏锡常浅层地下水的补径排条件。利用氢氧同位素的分析结果,建立潜水与微承压水的δD-δ18O关系曲线,分析潜水含水层与河流、湖泊等地表水体关系以及微承水的蒸发程度;利用放射性同位素氚与14C研究微承水与现代水的补给关系;利用常规的水化学分析方法研究浅层地下水补给源的变化问题。结合研究区地下水水位、地层岩性、地形、地貌等多方面因素综合分析了浅层地下水的补径排条件,从而指导苏锡常地区浅层地下水合理开发利用。 相似文献
5.
通过在苏锡常地区选择典型地段进行浅层地下水开采试验工作,从浅层地下水水文地质条件(含水层展布、岩性、厚度、水质)综合分析其开发利用前景,提出了合理的浅层地下水开采方式及地下水的利用方向,对于保护深层水资源,防止地面沉降及土壤盐渍化有十分重要的意义。 相似文献
6.
7.
苏锡常地区浅层地下水铁锰离子分布规律及成因分析 总被引：14，自引：1，他引：14
苏锡常地区浅层地下水资源较为丰富,但水中铁、锰离子含量一直较高.本文在总结现有水质资料的基础上,结合野外现场Eh测试、矿物及土壤的化学成分等成果,对浅层地下水中铁、锰离子的分布规律及其影响因素进行了研究,认为含水介质及土壤的化学成分、地下水系统中的氧化还原环境是造成该区浅层地下水中铁、锰离子含量较高的原因.在此基础上提出：加大开采力度,改善浅层地下水的循环交替速度有利于浅层地下水水质的改良. 相似文献
8.
利用~3H的示踪作用对珲春盆地浅层地下水更新速率进行计算,为该地区制定地下水开发利用模式和水资源环境承载力研究提供科学依据。结果表明:总体上,珲春盆地大部分地区浅层地下水更新速率大于8%/a,可更新能力较强。珲春盆地东北部平安村、新华村、马新村和东部的红星村、电线村、东兴村等山前地区以及八一村、八二村等地浅层地下水更新速率大于10%/a,可更新能力较强;七户洞村、八棵树村、永丰村、立新村、新农村、柳亭村等地浅层地下水更新速率为8%/a~10%/a,可更新能力减弱;八家子村、西崴子村、孟岭村等珲春河下游地区浅层地下水更新速率小于8%/a,可更新能力最弱。更新速率为大于10%/a、8%/a~10%/a、小于8%/a的地下水分布面积占珲春盆地总面积的比例分别为67%、26%、7%。 相似文献
9.
10.
江苏省政府召开苏锡常地区地下水管理工作会议江苏省政府于１９９６年１１月５日在锡山市召开江苏省苏锡常地区地下水管理工作会议。江苏省常务副省长季允石出席会议并作了重要讲话。省地矿厅、建委、水利厅、财政厅、物价局五部门领导及苏锡常三市分管副市长出席会议，苏... 相似文献
11.
Many cities in developing countries are dependent upon groundwater for water supply. Frequently this groundwater is pumped
from semi-confined aquifers in alluvial deposits. These deeper aquifers are often considered to be protected from polluted
shallow water by intervening less-permeable layers. However, where groundwater is pumped from a semi-confined aquifer immediately
beneath a city, significant induced leakage of contaminated shallow water can occur. This may lead to a serious deterioration
of water quality in deeper aquifers in the longer-term. A simple model has been developed which provides insight into the
hydraulic controls on water quality in such semi-confined aquifers. The model provides a tool for the initial assessment and
prediction of the impact of urbanization on groundwater quality. Also, the model characterizes the key hydrogeological behaviour
through a single parameter, here termed the ‘city leakage factor’, which can be used to assess the vulnerability to contamination
by leakage. A case study of a city in Thailand illustrates the use of this model.
相似文献
Résumé Beaucoup de villes des pays en développement dépendent de l’eau souterraine pour leur alimentation en eau. Cette eau souterraine est souvent pompée dans des aquifères alluviaux semi-captifs. Ces aquifères plus profonds sont souvent considérés comme protégés des eaux peu profondes et polluées, grace à des couches intercalaires moins perméables. Cependant, dans le cas où l’eau souterraine est pompée à partir d’un aquifère semi-captif situé directement sous une ville, une drainance importante des eaux peu profondes et polluées peut être induite. Ceci peut entra?ner, à long terme, une détérioration significative de la qualité de l’eau dans les aquifères plus profonds. Un modèle simple a été construit fournissant un aper?u des contr?les hydrauliques agissant sur la qualité de l’eau dans des aquifères semi-captifs. Ce modèle est un outil permettant d’évaluer l’état initial et de prédire l’impact de l’urbanisation sur la qualité de l’eau souterraine. Le modèle caractérise également les comportements hydrogéologiques majeurs à travers un unique paramètre, nommé dans cette étude facteur de drainance de la ville“, et qui peut être utilisé pour évaluer la vulnérabilité de l’aquifère face à une contamination par drainance. L’étude de cas d’une ville en Tha?lande illustre l’utilisation de ce modèle.
Resumen Muchas ciudades de paises en desarrollo dependen del agua subterránea para el abastecimiento de agua. Frecuentemente el agua subterránea se bombea de acuíferos semi-confinados en depósitos aluviales. Estos acuíferos más profundos se protegen frecuentemente de agua somera contaminada mediante la intervencción de capas menos permeables. Sin embargo, donde el agua subterránea se bombea de un acuífero semi-confinado inmediatamente debajo de una ciudad, pueden ocurrir fugas significativas inducidas de agua somera contaminada. Esto puede conducir a un serio deterioro de calidad de agua en acuíferos más profundos en el largo plazo. Se ha desarrollado un modelo simple el cual aporta idea acerca de los controles hidráulicos en la calidad del agua en tales acuíferos semi-confinados. El modelo aporta una herramienta para la evaluación inicial y predicción del impacto de urbanización en la calidad del agua subterránea. El modelo también caracteriza el comportamiento hidrogeológico clave a traves de un solo parámetro, que aquí se denomina ′factor de fuga de la ciudad′el cual puede usarse para evaluar la vulnerabilidad a la contaminación por fuga. El uso de este modelo se ilustra con un estudio de caso de una ciudad en Tailandia.
相似文献
12.
Krzysztof Dragon 《Environmental Earth Sciences》2012,65(4):1283-1290
This article presents the analysis of the temporal changes in water chemistry in a semi-confined aquifer (Wielkopolska Buried
Valley aquifer, Poland) during one decade of water exploitation. It is shown that the groundwater contamination, as documented
in a previous work, still persists and has lead to steady groundwater quality deterioration. The most intensive changes in
water chemistry due to contamination are observed in the regions recognized earlier as the most vulnerable parts of the aquifer.
The influence of contamination is effective despite implementation of groundwater protection activities. The travails of groundwater
quality protection of the confined or semi-confined aquifers were accented. 相似文献
13.
Installation of a vertical slurry wall around an Italian quarry lake: complications arising and simulation of the effects on groundwater flow 总被引：1，自引：0，他引：1
Slurry walls are non-structural barriers that are constructed underground to impede groundwater flow or manage groundwater
control problems. The study area is in the Piemonte plain (Italy), close to the River Po. Quarrying works carried out below
the piezometric surface created two big quarry lakes. The local groundwater system is characterized by a lower semi-confined
aquifer, which is overlain by a semi-permeable bed of clayey peat (aquitard) and an upper unconfined aquifer. Locally, the
peat fades away and the granulometry of this horizon becomes silty sandy. A planned enlargement of the quarry will increase
the size and depth of the quarry lakes. So the aquitard bed between the two aquifers will be damaged, creating a mixing rate
of groundwater. Such a procedure would not be compatible with the presence of two municipal wells upstream from the quarries.
Consequently, the installation of a vertical diaphragm (slurry wall) is recommended to separate the aquifers and to act as
a filter for the groundwater flowing from the unconfined to the semi-confined aquifer. To predict the consequences caused
by the installation of the vertical diaphragm separating the unconfined aquifer and the semi-confined one, a specifically
adjusted finite-difference model was used. The model showed a maximum rising of the water table equal to 12 cm, just upstream
of the diaphragm and for a distance of about 100 m, and a maximum lowering of 2 cm just downstream of the diaphragm. However,
the slurry wall would not cause any change in the piezometric head in the area where there are municipal wells and, hence,
will not have any negative effect on the functionality of the municipal wells. Moreover, the migration of water from the unconfined
aquifer through the vertical diaphragm will stimulate a series of attenuation and auto-depuration processes of eventual contaminants.
These processes are due to the higher crossing time that the groundwater flow takes to go through the vertical barrier (t
a = 96.5 days, whereas for the horizontal semi-permeable layer t
a = 9.6 days). So, the vertical diaphragm can be a resolutive element, representing a mediation and separation factor between
the unconfined and the semi-confined aquifers along the border of the quarrying areas, and a protective barrier for the water
quality of the quarry lake and the semi-confined aquifer. 相似文献
14.
In this study, the changes in the chemical composition of the groundwater along a flow path were examined by using the water
samples collected from unconfined, semi-confined and confined parts of the Karasu karstic aquifer. It was determined that
transport of bicarbonate, calcium, and magnesium was dominant in unconfined and semi-confined parts of the aquifer, whereas
calcite and dolomite precipitate in the confined parts. On the other hand, gypsum dissolution is present in all parts of the
aquifer. In addition, the computed saturation indices explain the occurrences and precipitation of travertines in the Goksu
Valley, which is the discharge area for the aquifer.
Electronic Publication 相似文献
15.
A. Lawrence D. Gooddy P. Kanatharana W. Meesilp V. Ramnarong 《Hydrogeology Journal》2000,8(5):564-575
Many cities and towns in South and Southeast Asia are unsewered, and urban wastewaters are often discharged either directly
to the ground or to surface-water canals and channels. This practice can result in widespread contamination of the shallow
groundwater. In Hat Yai, southern Thailand, seepage of urban wastewaters has produced substantial deterioration in the quality
of the shallow groundwater directly beneath the city. For this reason, the majority of the potable water supply is obtained
from groundwater in deeper semi-confined aquifers 30–50 m below the surface. However, downward leakage of shallow groundwater
from beneath the city is a significant component of recharge to the deeper aquifer, which has long-term implications for water
quality. Results from cored boreholes and shallow nested piezometers are presented. The combination of high organic content
of the urban recharge and the shallow depth to the water table has produced strongly reducing conditions in the upper layer
and the mobilisation of arsenic. A simple analytical model shows that time scales for downward leakage, from the surface through
the upper aquitard to the semi-confined aquifer, are of the order of several decades.
Electronic Publication 相似文献
16.
Identification of hydrogeochemical zones in postglacial buried valley aquifer (Wielkopolska Buried Valley aquifer,Poland) 总被引：3，自引：0，他引：3
This article presents the difficulty in identifying the hydrochemical zoning of a semi-confined aquifer, characterised by
a relative small spatial differentiation of groundwater chemistry. It is shown that multivariate statistical methods can be
used for the recognition and interpretation of the groundwater chemistry distribution in an aquifer. The hydrochemical zonation
caused by both natural and anthropogenic processes was identified using factor analyses in combination with a classical interpretation
of the hydrogeological material. The interpretation of the groundwater chemistry allows both identification of the aquifer
recharge mechanism and verification of the groundwater-flow system. 相似文献
17.
A hydrodynamic study of a coastal karstic aquifer is attempted by analyzing the effect of sea-tide on its water table Under
certain conditions, this approach, which involves quite easy data processing, may yield the hydrodynamic parameters of the
aquifers, diffusivity, in particular. The aquifer involved here is the Kras of Slovenia, Yugoslavia, which is bounded on one
side by the Adriatic Sea (Bay of Trst)Kras is the Slovenian word from which the wordkarst originates
The Kras aquifer is located in a thick carbonate sequence (Cretaceous) with an anticline structure. This sequence outcrops
and is affected by opened vertical fractures. The geological setting could suggest a free groundwater with negligible piezometric
variations with respect to the thickness of the carbonate sequence
The study was carried out by the identification of observed data (fluctuations of the water table) and computed data under
various assumptions (confined, semi-confined, free groundwater). The best fit is obtained when considering a groundwater with
semi-confined behavior, which, of course, does not agree with the geological setting of the Kras
However, this behavior can be justified by the fact that an important karstification occurred below the existing sea-level
during the Quaternary and Tertiary marine recessions, creating diffusive zones in lower parts of the saturated karst it should
be noted that similar situations must prevail in all the peri-Mediterranean karsts as they too were affected by the Quaternary
and Tertiary recessions 相似文献
18.
Ground penetrating radar (GPR) has proved to be an extremely useful geophysical tool, in conjunction with direct geological data, to develop a realistic, macroscopic, subjective-based conceptual model of aquifer architecture within a shallow coastal alluvial plain. Subsequent finite-difference groundwater modelling has not only enabled determination of the dominant groundwater flow paths for the plain, but has also quantified the effects of within-facies and between-facies sedimentary heterogeneity on those flow paths. The interconnection of narrow, unconfined alluvial channels and a broad, semi-confined alluvial delta is ensuring that most fresh groundwater that enters the plain in the form of precipitation or recharge from lateral bedrock hills, is discharged into the eastern coastal wetlands via that alluvial delta aquifer. 相似文献
19.
Magdy M. S. El Maghraby Ahmad Kh. O. Abu El Nasr Mahmoud S. A. Hamouda 《Environmental Earth Sciences》2013,70(4):1525-1538
Groundwater is the main source of irrigation within south Al Madinah Al Munawarah region. It is also an important source of drinking water in many areas including Madinah city. The wells installed in the aquifer of the study area (south Madinah city) are not currently regulated by the local authorities although they are a key component of water supply. The aquifers in the study area range from unconfined to semi-confined and confined. The main aim of this study is to assess the groundwater in the region for drinking and agricultural uses. For this purpose, hydrochemical analyses of major, minor and trace constituents and nutrients were performed on 29 groundwater samples from the aquifer located about 20 km south of Madinah. The recharge rate of the aquifer of the study area was estimated to be 6.58 % of the annual precipitation using the chloride mass-balance method. Chloride was positively correlated with major ions, which suggests that agricultural activities have some effect on groundwater chemistry through leaching of readily soluble salts from the soil zone. Groundwater of the study area is characterized by dominance of Na over Ca. Chloride was found to be the most dominant anion and replaced by HCO3, thus reflecting geochemical evolution in the study area. The groundwater of the study area is not safe for drinking but can be safely used for salt-tolerant crops. 相似文献
20.
Study of subsurface geology in locating arsenic-free groundwater in Bengal delta,West Bengal,India 总被引：1，自引：0，他引：1
Over a large area of the Bengal delta in West Bengal, India, arsenic distribution patterns in groundwater were studied. One
hundred and ten boreholes at different target locations were made, subsurface sediments were logged and analysed, and arsenic
values in sediments vis-à-vis groundwater were compared. The study elucidates the subsurface geology of the western part of
Bengal delta and characterises the sediments that were intersected in different boreholes with contrasting values of arsenic
in groundwater. It reveals an existence of multiple aquifers stacked over each other. Depending on the color and nature of
aquifer-sands and their overlying clay beds six aquifer types (Type-1 to Type-6) are classified and described. Sediment-arsenic
for all the varieties of aquifer sands are near similar but the groundwater-arsenic of these six aquifers varies widely. Type-2
and Type-5 aquifers host arsenic-contaminated groundwater whereas the other four aquifers are arsenic-free. Type-2 and Type-5
aquifers are capped by a grey to dark grey soft organic matter-rich clay unit which makes these aquifers semi-confined to
leaky-confined. These contribute in releasing arsenic from the sediments. The results of this study are employed in a proposed
georemedial measure against this hazardous toxic element. 相似文献