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171.
为进行某铁路隧道的设计与施工,获取相关的水文地质参数,进行了3个钻孔的抽水试验,以获取相关的水文地质参数。运用地下水径流模数法、大气降雨入渗法和地下水动力学法对隧道涌水量进行了计算,计算结果显示:地下径流模数法的计算值偏小,降水入渗法的计算值适中,地下水动力学法的精度较高,但计算的涌水量值较大;三种方法比较,决定结果采用大值,即涌水量正常值取6150m^3/d,最大涌水量值取9770m^3/d。提出了采用双向自流排水,适当布设施工监控设备的工程建议。  相似文献   
172.
利用宋桥井田奥灰群孔抽水试验资料,根据补(隔)水边界水位曲线的特征,采用半对数直线图解法,将井田F2-9断层定性为补给边界。为了解补给边界的补给量,选用边界补给量计算方法.计算出了边界补给量占孔流量的65%,从而较客观地确定了井田水文地质条件类型。  相似文献   
173.
水平水井是开采浅层低渗透性含水层地下水的有效方法,水平水井施工包括钻进、护壁、扩孔、井管安装、填砾、洗井等步骤.对导向钻进铺管技术在浅层低渗透性含水层地下水开采中的工艺进行了详细探讨.通过研究,研制出了适合水平水井施工的过滤器,提出了相适应的钻进方法和成井工艺,为浅层低渗透性含水层地下水开采提供了一种新方法.  相似文献   
174.
Citation Abrahart, R.J. & Mount, N.J. (2011) Discussion of “Neuro-fuzzy models employing wavelet analysis for suspended sediment concentration prediction in rivers by S.A. Mirgagheri et al. (2010, Hydrol. Sci. J. 55(7), 1175–1189).” Hydrol. Sci. J. 56(7), 1325–1329.  相似文献   
175.
Abstract

We investigate the general methodology for an intensive development of coastal aquifers, described in a companion paper, through its application to the management of the Akrotiri aquifer, Cyprus. The Zakaki area of that aquifer, adjacent to Lemessos City, is managed such that it permits a fixed annual agricultural water demand to be met, as well as and a fraction of the water demand of Lemessos, which varies according to available surface water. Effluents of the Lemessos wastewater treatment plant are injected into the aquifer to counteract the seawater intrusion resulting from the increased pumping. The locations of pumping and injection wells are optimized based on least-cost, subject to meeting the demand. This strategy controls sea intrusion so effectively that desalting of only small volumes of slightly brackish groundwater is required over short times, while ~2.3 m3 of groundwater is produced for each 1 m3 of injected treated wastewater. The cost over the 20-year period 2000–2020 of operation is ~40 M€ and the unit production cost of potable water is under 0.2 €/m3. The comparison between the deterministic and stochastic analyses of the groundwater dynamics indicates the former as conservative, i.e. yielding higher groundwater salinity at the well. The Akrotiri case study shows that the proposed aquifer management scheme yields solutions that are preferable to the widely promoted seawater desalination, also considering the revenues from using the treated wastewater for irrigation.

Citation Koussis, A. D., Georgopoulou, E., Kotronarou, A., Mazi, K., Restrepo, P., Destouni, G., Prieto, C., Rodriguez, J. J., Rodriguez-Mirasol, J., Cordero, T., Ioannou, C., Georgiou, A., Schwartz, J. & Zacharias, I. (2010) Cost-efficient management of coastal aquifers via recharge with treated wastewater and desalination of brackish groundwater: application to the Akrotiri basin and aquifer, Cyprus. Hydrol. Sci. J. 55(7), 1234–1245.  相似文献   
176.
ABSTRACT

The point dilution test is a single-well technique for estimating horizontal flow velocity in the aquifer surrounding a well. The test is conducted by introducing a tracer into a well section and monitoring its decreasing concentration over time. When using a salt tracer, the method is easy and inexpensive. Traditionally, the horizontal Darcy velocity is calculated as a function of the rate of dilution and is based on the simple assumption that the decreasing tracer concentration is proportional both to the apparent velocity into the test section and to the Darcy velocity in the aquifer. In this article, an alternative approach to analyse the results of point dilution tests is proposed and verified using data acquired at a test site in the middle Venetian plain, northeast Italy. In this approach, the one-dimensional equilibrium advection–dispersion equation is inverted using the CXTFIT model to estimate the apparent velocity inside the test section. Analysis of the field data obtained by the two approaches shows good agreement between the methods and suggests that it is possible to use the equilibrium advection–dispersion equation to estimate apparent velocity over a wide range of velocities.
Editor D. Koutsoyiannis; Associate editor K. Heal  相似文献   
177.
《水文科学杂志》2013,58(3):526-537
Abstract

The study of the Continental Intercalaire aquifer system of southern Tunisia, based on the interpretation of geochemical (major elements) and isotopic (18O, 2H, 13C and 14C) data, has aided the understanding of the hydrodynamics of this multi-layer aquifer system, which is greatly influenced by tectonics. The determination of the origin of groundwater salinization and the understanding of the hydrogeological and geochemical behaviour of this aquifer were achieved by studying the correlation between the major elements and total mineralization (TDS). By using isotopic tools, it was shown that the water of this aquifer has been recharged under cooler, palaeoclimatic conditions. The technique also made it possible to better understand the hydrodynamic functioning of the aquifer system: it showed that the relatively recent recharge of the aquifer has been by direct infiltration from carbonate and sandy outcrops of the Cretaceous and Miocene, respectively, located in the eastern and northeastern parts of the aquifer. The 18O content was used to calculate the altitude of recharge basins. The isotopic gradient defined in this study is ?0.5 δ18O ‰/100 m.  相似文献   
178.
应用井孔-裂隙、微裂隙(孔隙)水流交换产生的潮汐水位-固体潮的位相差和振幅变化理论,结合井水位变化,分析小江断裂带中段和南段的形变特征.裂隙承压含水层条件下,地震波和构造应力引起的形变能够引起潮汐水位分波位相差和振幅的变化.地震波引起含水层与井孔之间水流交换增大,疏通裂隙而使渗透率增大,震后井水位潮汐分波相位差提前,其后裂隙内沉积物重新堵塞裂隙,渗透率降低,位相差逐渐下降.位相差的长期趋势性变化反映出含水层在构造应力作用下的应变信息.小江断裂带中段和南段形变变化不同.断裂带中段地区,观测井位相差和振幅趋势性下降,表明该区段不仅有走滑特性,并且具有挤压特征.小江断裂带与红河断裂带交会地区观测井振幅和位相差稳定,表明该区域没有受到明显的挤压,形变不明显.  相似文献   
179.
Abstract

The multi-layered Jeffara de Gabes aquifer system is greatly influenced by tectonics. This system is limited at the base and laterally by evaporite layers and has lateral contacts with the sebkhas (salt flats). The groundwater in this aquifer is characterized by high salinity (3–10 g L-1). Multivariate statistical analysis and a geochemical approach were applied to determine the influence of the evaporite layers and sebkhas on the hydrochemical quality of the Jeffara de Gabes aquifer, and to understand the processes governing its salinity. According to these methods, and based in part on the Sr2+/Ca2+ ratio, it is demonstrated that the strong salinity of the groundwater is due to interactions between water and the evaporite layers that act as a substratum of this aquifer, as well as saltwater intrusion from the sebkhas. Moreover, the medium- to poor-quality groundwaters are characterized by geochemical interactions: cationic exchange and the precipitation/dissolution process of minerals in the aquifer formations.

Editeur Z.W. Kundzewicz

Citation Ben Alaya, M., Zemni, T., Mamou, A. et Zargouni, F., 2014. Acquisition de salinité et qualité des eaux d’une nappe profonde, Tunisie: approche statistique et géochimique. Hydrological Sciences Journal, 59 (2), 395–419.  相似文献   
180.
《水文科学杂志》2013,58(4):700-712
Abstract

The groundwater flow equation governing the elevation (h) of the steady-state phreatic surface in a sloping aquifer fed by constant recharge over a bi-circular sector is rhh′ ? r 2 Bh′ + Pr 2 ? PR 2 = 0, where r is the radial coordinate, P is a constant involving recharge and aquifer properties, and B is the slope of the aquifer—bedrock boundary. The derived flow equation describes radially convergent flow through a sloping aquifer that discharges to a water body of fixed head. One important simplification is that in which the width of the bi-circular sector is constant, and the draining land becomes a rectangular aquifer. The bi-circular sector and rectangular-strip groundwater flow problems are solved in terms of implicit equations. The solutions for the steady-state phreatic surfaces depend on the ratio of recharge to hydraulic conductivity, the slope of the aquifer-bedrock, and the downstream constant-head boundary. Computational examples illustrate the application of the solutions.  相似文献   
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