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"四水"转化研究综述 总被引：6，自引：0，他引：6
“四水”是指大气水、地表水、土壤水和潜水,“四水”之间的相互转化关系研究,对水资源评估、供需预测、合理开发利用水资源和节水灌溉都有十分重要的意义。本文总结前人在八个8方面“四水”两两之间相互转化的研究成果．归纳了“四水”转化研究存在的问题,讨论了未来的研究重点。 相似文献
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Alessandro Tarantino Andrew M. Ridley David G. Toll 《Geotechnical and Geological Engineering》2008,26(6):751-782
This paper presents a review of techniques for field measurement of suction, water content, and water hydraulic conductivity
(permeability). Main problems in the use of field tensiometers are addressed and hints on how to improve tensiometer performance
are given. Advantages and limitations of instruments for indirect measurement of suction including electrical conductivity
sensors, thermal conductivity sensors, dielectric permittivity sensors, filter paper, and psychrometer are discussed. Techniques
for water content measurement based on dielectric methods are then presented. These include time and amplitude domain reflectometry
and capacitance. Finally, a brief overview of methods for measurement of water permeability in the field is presented. 相似文献
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John G. Lockwood 《Quaternary Research》1979,12(3):297-310
Estimates made of lowland precipitation and evaporation in Britain during the last (Devensian) glaciation suggest that during the cold periods of the Devensian precipitation was probably low, between 260 and 370 mm/year, with winter precipitation between 80 and 120 mm, whereas at the thermal maximum of the Upton Warren Interstadial lowland precipitation was probably in the range 450 to 650 mm/year. Two summer precipitation regimes are identified during the cold periods, one with high values and the other with low. The high summer precipitation variant leads to moist conditions with July and August precipitation values similar to those at the present day, and global circulation models suggest that the moist regime may have existed at the time of the maximum advance of the ice sheets. On the other hand, the low summer precipitation variant leads to a dry summer with wind action creating aeolian deposits, and this variant probably existed at earlier times in the glacial period. About 6500 yr B.P., in the Atlantic period, forest conditions probably caused increased evaporation which more than compensated for the increased precipitation of the time, causing low runoff conditions. The clearance of British forests by man since 6500 yr B.P. has probably led to an absolute increase in runoff values even though precipitation values have fallen. 相似文献
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101采区位于煤矿的中部,拟采10煤层,区内抽水资料较少.在合理利用采区内、外各种水文地质资料基础上,通过对矿井水文地质边界条件的划分,充水水源、充水途径的分析,论述了采区的充水因素.研究认为,采区东部DF2.可视为采区补给边界;南、西、北分别被F14、WF4、F高-7断层切割,可视为隔水边界;10煤顶、底板砂岩裂隙含水层(段)是直接充水水源,富水性弱;新生界松散层第四含水层(组)是间接充水水源,富水性亦弱;太原组石灰岩岩溶裂隙含水层(段)是间接充水水源,富水性弱-中等;充水途径主要有构造裂隙、垮落带、导水裂缝带、断层及岩溶陷落柱以及未封闭好的钻孔等.该研究为采区涌水量计算、水害的防治及采区工作面的设计提供了较为可靠的地质资料. 相似文献
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Natural granite and gabbro samples, with dimensions of the orderof 1 cm, were exposed up to 48 hours to water at a pressureof 2 kb and temperatures up to 1060 °C, in an internallyheated pressure vessel. Spatial and temporal nonequilibriummelt distributions were quantitatively studied in thin sectionsof the quenched samples. The main observations, in granite atabout 1020 °C, indicated that melting fronts were initiatedat grain boundaries exposed to water and advanced at initiallyhigh rates subject to rate limitation by water diffusion throughthe deepening melt. The melting slowed down sharply with a slightundersaturation due to exhaustion of free water in the inter-granularvoids. The experimental observations on melting rates and water diffusion,as a function of water concentration and temperature, are correlatedwith data derived from other studies. A new model is advancedfor water diffusion in granitic magma. It is demonstrated thatrate processes in silicate melts may be significantly acceleratedby water in differing patterns. Water diffusion in graniticmelt is rather insensitive to water concentration whereas meltingkinetics and fluidity are strongly enhanced by water but significantlydecoupled from each other, all in contradiction to standardkinetic theories. Melting kinetics is shown to be especiallycritical in physical experiments on melting rock, and some observationson electrical conductivity are accordingly re-interprete. 相似文献
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Philip E. LaMoreaux Ph.D. 《Environmental Geology》1990,16(3):169-169
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皖南南部牯牛降地区地质遗迹众多,位于祁门牯牛降国家地质公园的流水淘蚀地貌和新构造运动遗迹非常具有代表性,为普及地学知识提供了生动的教材,具有较高的科学研究价值。 相似文献
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钱供２孔矿泉水赋存于奥陶系碳酸盐岩裂隙溶洞中，供水井深１０００ｍ，利用含水段６２３．５～１０００ｍ，为深层含锶型矿泉水，银含量高达４．８１ｍｇ／Ｌ。水化学类型为ＳＯ＿４·ＨＣＯ＿３－Ｃａ·Ｍｇ型水。允许开采量５００ｍ￣３／ｄ。钱家营矿地势平坦，交通方便，水质优良，具有良好的开发前景。 相似文献
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黔西林泉片区表层岩溶带发育特征及供水 总被引：1，自引：0，他引：1
贵州省黔西县林泉片区属于深切河谷斜坡地带,区内地下水位受乌江期隆升作用埋深大,不利于地下水的开发利用;且区内缺水人口分散分布于河谷斜坡地带,不利于集中供水。所以对区内表层岩溶带发育及表层带岩溶水分布特征的研究,是解决区内缺水问题的关键。 相似文献
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山西朔州市北邢家河饮用天然矿泉水 总被引：1，自引：0，他引：1
朔州市北邢家河村ＳＢ－２井，为第四系松散层孔隙承压水，井深７ｌｍ，水位埋深１０．０５ｍ。动水位埋深１７．８ｍ，涌水量５８．８５ｍ￣３／ｈ。经权威部门理化检测，省级评审确认该井水为低矿化度、锶、重碳酸钙·镁型饮用天然矿泉水，具良好的开发利用条件。 相似文献
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Ven Te Chow 《Earth》1973,9(4):375-376
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Uplift deformation of Jiangya Dam in Loushui River, Hunan Province, P.R. China reached 28.4–32.6 mm in 2 years and 5 months (December 1998–April 2001), which is unusual for dams worldwide. A perfectly confined aquifer, Yuntaiguan hot water aquifer, in the Jiangya syncline is recharged at a remote wing and outflows in front of the dam in the reservoir which is 875 m lower than the recharge point. The rise of the reservoir water level increases the head in the aquifer. The uplift deformation of the dam foundation corresponds spatially with the outcrop of the top interface of the aquifer and shows a direct time response to the fluctuation of the reservoir water level, indicating that the fluctuation of the reservoir water level is the dominant influence on the deformation. Numerical simulation shows spatial and dynamic similarities to the monitoring data. Numerical simulation of the cyclic reservoir water level confirms that the uplift is due to elastic deformation.
Resumen En la presa de Jiangya en el rio Loushui, Provincia de Hunan, R. P. De China, la deformación por levantamiento alcanzó 28.4–32.6 mm en dos años y cinco meses (Diciembre 1998–Abril 2001), lo cual no es común para las presas alrededor del mundo. El acuífero de Yuntaiguan, con agua caliente, es perfectamente confinado, y es recargado en un flanco lejano del sinclinal de Jiangya, descargando su flujo enfrente de la presa, dentro del embalse, sitio que está 875 m más bajo que el punto de recarga. El aumento en el nivel del embalse, incrementa la cabeza en el acuífero. La deformación por levantamiento en la cimentación de la presa tiene una correspondencia espacial con el afloramiento de la interfase superior del acuífero y muestra una respuesta directa en el tiempo con la fluctuación del nivel del agua en el embalse, indicando que la fluctuación del nivel del agua en el embalse es la influencia dominante sobre la deformación. La simulación numérica muestra similitudes espaciales y dinámicas con los datos de monitoreo. La simulación numérica del nivel de agua cíclico del embalse, confirma que el levantamiento se debe a deformación elástica.
Résumé Pendant deux ans et cinq mois ( Décembre 1998–Avril 2001) les déplacements verticaux du barrage Jangya, situé sur la rivière Loushui, dans la province Hunan de la R.P. de Chine ont atteint des valeurs peu communes, de 28.4–32.6 mm. Laquifère thermal captive de Yuntaiguan est rechargé sur le flanc lointain du synclinal de Jiangya, où il est cantonné et se décharge dans le réservoir du barrage dont le niveau et avec 875 m au dessous du point de recharge. Le niveau piézometrique de laquifère est augmenté par la housse de niveau dans le réservoir. Les déplacements verticaux correspondent au laffleurement du toit de laquifère et présentent une réponse temporelle directe aux fluctuations de niveaux du réservoir, en indiquant que celles-ci ont une influence dominante sur les déplacements. Les simulations numériques montrent des similarités spatiales et dynamiques avec les données du système de surveillance. Les simulations numériques de variations cycliques des niveaux du réservoir ont confirmé que les déplacements verticaux sont engendrées par des déformations élastiques.相似文献
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A variety of water supply sources are used in the rural Guatemalan Highlands. Formal municipal systems are rare, but villagers
frequently form local water committees that construct spring-based supply systems. Recent work has indicated that groundwater
may be a viable water supply source. The water quality from these two sources was characterized as well as water from other
common sources including surface water and precipitation collection systems. Typically, all of the water sources contained
unacceptable levels of coliform bacteria except for groundwater from a drilled well. Water monitoring indicated that not only
did the water contain coliforms at the actual sources, but the infrastructure used to transmit the water to points of use
may also be a source of coliforms. A cost comparison indicates that groundwater may be a cost-competitive, higher quality
alternative to traditional spring-fed water systems. 相似文献