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基于涠洲岛地下淡水透镜的水文地质特下和地下水资源勘查,开发利用中出现和经验分析,提出了地下水资源合理开发利用和保护对策。 相似文献
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瞬变电磁法在地下水勘查中的应用研究综述 总被引：5，自引：1，他引：5
水是地球上最重要的天然资源,供人类需要的淡水有95%以上取自地下水,地下水在人类经济活动中发挥着重要的作用.传统的地球物理方法在地下水勘查工作中得到应用的同时,新的更先进的物探方法不断涌现.近年来,瞬变电磁法在国内外的应用得到迅速发展,在地下水勘查领域的应用也得到拓展.与其它电探方法相比,利用瞬变电磁法进行地下水勘查具有明显优势. 相似文献
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苏宏图地区地下淡水形成机制 总被引：3，自引：3，他引：0
本文在前人工作的基础上,通过进一步的地质、水文地质调查,地球物理勘探,水文地质钻探,在阿拉善北部苏宏图寻找了可资应用的地下淡水,依据地貌、地层结构、地质构造和补径排特征分析了该区地下淡水的赋存和运移机制,对于同类干旱区地下水的勘查具有重要的意义。 相似文献
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笔者等对我国盐湖矿床的勘查工作及盐湖矿产勘查规范的制修订过程进行了梳理、总结,认为盐湖卤水矿作为一种液体矿床,水只是其载体,其本质属性是矿,在开展水文地质工作的同时,按照矿产的勘查方法查明卤水及共伴生矿产资源储量,开展综合评价是一种适合的勘查方法;盐湖卤水矿勘查规范的制定和修订是对多年来盐湖卤水勘查工作的总结和完善,符合卤水矿的勘查实际,勘查成果被矿山的设计及开采所验证,总体是一部适用的规范。钱先生提出的按照地下水的勘查、评价方法去勘查盐湖卤水矿产,忽略了卤水矿的属性及固液共生的特点,夸大了周边水补给对盐湖矿产的影响,提出的可采储量与矿山设计部门计算的可采储量的约束条件不同,故不能用淡水资源的评价方法去评价卤水矿。 相似文献
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本文对我国盐湖矿床的勘查工作及盐湖矿产勘查规范的制修订过程进行了梳理、总结,认为盐湖卤水矿作为一种液体矿床,水只是其载体,其本质属性是矿,在开展水文地质工作的同时,按照矿产的勘查方法查明卤水及共伴生资源储量,开展综合评价是一种适合的勘查方法;盐湖卤水矿勘查规范的制定和修订是对多年来盐湖卤水勘查工作的总结和完善,符合卤水矿的勘查实际,勘查成果被矿山的设计及开采所验证,总体是一部适用的规范。钱先生提出的按照地下水的勘查、评价方法去勘查盐湖卤水矿产,忽略了卤水矿的属性及固液共生的特点,夸大了周边水补给对盐湖矿产的影响,提出的可采储量与矿山设计部门计算的可采储量的约束条件不同,故不能用淡水资源的评价方法去评价卤水矿。 相似文献
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测井技术一直以来普遍应用于煤田、天然气、淡水资源、石油、固体矿产等领域,取得了不少的成果及经验,但在深层卤水资源勘查中应用较少.通过分析研究"青海省冷湖镇马海地区深层卤水钾矿勘查"等诸多项目的测井成果,总结出三侧向电阻率、自然伽马、声波时差、自然电位等参数在新生代地层中的特征,发现普通测井方法在盐湖资源勘查中有很大的指导作用,是深层卤水资源勘查不可或缺的勘探方法.通过统计分析大量盆地内的测井资料,找出测井曲线的形态特征与单井层序之间的关系,然后使用定量识别来分析和验证自然伽马、声波时差等参数范围及曲线特征,总结出适合柴达木盆地深层卤水勘查的测井解释方法. 相似文献
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本文以近年来在西宁盆地人畜饮用供水地下水勘查示范工程取得的最新资料为基础，通过对区内碎屑岩类储水构造模式的研究，分析研究区内干旱缺水村镇地下淡水赋存规律与形成机理，以期为类似地区居民基本生活饮用水的解决提供依据。 相似文献
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《地质科技情报》2020,(2)
为了了解频率域航空电磁法在水资源勘查中的应用条件和勘查效果,以层状介质模型为基础,计算了多种水文地电模型、多种电磁系统装置的频率域航空电磁响应。通过分析吊舱式直升机频率域航空电磁系统、固定翼频率域航空电磁系统在不同水文地电模型的电磁响应特征和衰减规律,分析了这2套系统在不同水文地电模型条件下的探测深度,即在盐渍化地区,频率域航空电磁系统最大勘探深度为60 m,在非盐渍化地区最大勘探深度为130 m。在综合分析频率域航空电磁法在水资源勘查应用前景的的基础上,通过国内外应用实例表明,频率域航空电磁法在中国东部沿海地区,以及内陆干旱地区寻找浅层淡水是有效的。该项成果对今后利用频率域航空电磁法进行水资源调查具有重要意义。 相似文献
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根据电测井所得数值,通过造浆水影响改正及颗粒度影响改正后,利用相关图判定地层水矿化度,达到半定量或接近定量分析水平,完成淡水勘探中只对淡水层进行评价,进而实现无岩心钻进,结合抽水试验结果,优化取水位置,获取水质好、涌水量大的效果。 相似文献
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Little is known about the century‐scale response of water levels in inland estuaries to sea‐level change and human modifications to estuarine morphology. This study explored the ability of using testate amoebae (Protozoa, Rhizopoda) from sediments of a freshwater tidal marsh as indicators of water level in an inland estuary. The hypothesis was that modern testate amoeba assemblages change with surface elevation (approximately the duration of tidal flooding) within a freshwater tidal marsh. Variation in testate amoeba assemblages in relation to multiple environmental variables and sediment characteristics was studied through redundancy analysis. This demonstrated that a significant part of the variation in modern testate amoeba assemblages could be explained by flooding frequency, surface elevation, organic content and particle size of the soil. Transfer functions, partial least squares and weighted average regressions were made to show that testate amoebae can be used for reconstruction of water level (with an accuracy of 0.05 Normalized Elevation). A preliminary test of application of the transfer function to palaeo testate amoeba assemblages showed promising results. Testate amoebae from a freshwater tidal marsh provide a potentially powerful new tool for estuarine water‐level reconstructions. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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Robert A. Mattson 《Estuaries and Coasts》2002,25(6):1333-1342
The availability of methods for establishing freshwater inflow requirements for estuaries lags behind those for establishing flow requirements in riverine ecosystems. Some of the basic principles and approaches for establishing riverine flow requirements may be applicable to estuaries. An emerging approach for establishing freshwater inflow needs for the Suwannee River estuary involves maintaining a natural inflow regime (in terms of magnitude, frequency, duration, and timing of freshwater flows) and identifying important habitat targets to be protected. The salinity-river flow conditions needed to sustain the habitat targets in their existing condition are then identified. A variety of tools are employed, such as salinity metrics, biological metrics, limits of distribution of communities or habitats, and landscape-scale characteristics to define the salinity and corresponding flow ranges needed to protect and maintain the resource targets. With this information, combined with use of models to evaluate flow-salinity relationships and various withdrawal scenarios, river flow criteria can be set which address the freshwater inflow requirements to maintain these ranges. Subsequentmonitoring and research is undertaken to evaluate the effectiveness of the river flow criteria in protecting the estuarine resource targets. This information can be used to subsequently confirm, refine, or modity the flow criteria. 相似文献
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Saltwater intrusion into coastal freshwater aquifers is an ongoing problem that will continue to impact coastal freshwater resources as coastal populations increase. To effectively model saltwater intrusion, the impacts of increased salt content on fluid density must be accounted for to properly model saltwater/freshwater transition zones and sharp interfaces. We present a model for variable density fluid flow and solute transport where a conforming finite element method discretization with a locally conservative velocity post-processing method is used for the flow model and the transport equation is discretized using a variational multiscale stabilized conforming finite element method. This formulation provides a consistent velocity and performs well even in advection-dominated problems that can occur in saltwater intrusion modeling. The physical model is presented as well as the formulation of the numerical model and solution methods. The model is tested against several 2-D and 3-D numerical and experimental benchmark problems, and the results are presented to verify the code. 相似文献
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基于水量平衡的博斯腾湖水位变化分析 总被引：2，自引：0，他引：2
博斯腾湖是我国最大的内陆淡水湖,也是新疆南部地区重要的淡水资源。20世纪50年代以来,博斯腾湖水位多次剧烈变动。尤其是近30年,博斯腾湖水位波动尤为剧烈,甚至有不断加剧的趋势,这给该区经济建设和生态环境造成重大负面影响。基于水量平衡原理,分析博斯腾湖流域1986~2012年的气象水文数据,得到1986~2002年博斯腾湖水位急剧上升的原因在于开都河径流量的增加及开都河灌区引水量的减少。2002~2012年,开都河径流量持续走低,地下水的开采导致河道损失水量增大以及泵站扬水量的增加使得博斯腾湖水位急剧下降。 相似文献
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The Nueces River is the primary source of freshwater inflow to Corpus Christi Bay and virtually the only source of freshwater inflow in the Nueces Delta. In association with reservoir development and operation within the Nueces Basin, the magnitude of freshwater inflow has been greatly reduced since 1958. Continually increasing salt concentrations in the soil and water have compromised the function of the delta as a viable component of the estuarine ecosystem. In 1993, the U.S. Bureau of Reclamation began a 5-yr diversion project to increase the opportunity for freshwater flow into the delta. With the excavation of two overflow channels, the minimum flooding threshold for the upper delta was significantly lowered, and more frequent diversions of freshwater from the Nuecess River were enabled. During the 50-mo diversion period, the amount of freshwater diverted into the upper Nueces Delta was increased sevenfold. The average salinity gradient in the upper delta reverted to a more natural pattern, with average salinity concentrations decreasing from the lower (bay) to upper (riverine) delta, and a corresponding improvement in abundance and diversity of both intertidal vegetation and benthic communities. 相似文献
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洞庭湖是我国第二大淡水湖。以往用补给量代替天然资源的方法计算其孔隙水天然资源,对地表水渗漏量很难计算,可信度低。用均衡法计算洞庭湖盆孔隙水天然资源,回避了直接计算地表水补给量,加深了孔隙水补给排泄的认识,计算结果亦较准确,故此种方法是地处暖湿亚热带、水系高度发育的湖盆孔隙水天然资源计算的较好方法。 相似文献
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A new methodology used on a large scale is reported by which short-term (≤1 yr) marsh accretion rates were measured in saltwater and brackish marshes and compared to first-time measurements made in freshwater marshes. The stable rare-earth elements (REE) dysprosium and samarium were used for soil horizon markers that were collected by a cryogenic field coring method and detected by instrumental neutron activation analysis (INAA). Accumulation in saltwater marshes for 6 months was estimated to be 0.76±0.26 cm (n=11) and accumulation for 1 year was 1.29±0.49 cm (n=7). Accumulation in brackish marshes for 6 months was 0.51±0.34 cm (n=6) and for 1 year, 0.84±0.32 cm (n=10). These data from saline and brackish environments can be compared to first-time measurements of accumulation in a freshwater marsh of 1.53±0.66 cm (n=8) for 6-month accumulation and 2.97±0.92 cm (n=11) for 1-year accumulation. The cryogenic REE-INAA method for sampling and measuring 6-month and 1-year accretion is nonpolluting, does not alter natural marsh soil processes, and is effective in salt, brackish, and freshwater marshes. Additionally, the marker is essentially immobile, long lasting in the soil profile, and inexpensive to buy, apply, and sample. INAA analysis of the cores is expensive and time-consuming, yet the REE-INAA method yields accretion data, especially in freshwater habitats, that are obtainable in no other way. A comparison between short-term accretion and the presence or absence of man-made canals showed no statistically significant differences of accretion along transects from 0- to 50-m distance into brackish and saltwater marshes (no freshwater transects were established). Sediment depositions measured at 50 m into fresh, brackish, and saltwater marshes from natural or man-made waterways showed no statistically significant differences of accretion within each habitat over a 6-month or a 1-year time period. 相似文献
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P. Lindsay 《Environmental Geology》1996,28(4):201-212
Spatial variations in the density and velocity fields have been observed in the Gareloch (Scotland) during surveys in 1987–1988
and 1993–1994. The variation of the density field has been analyzed on a variety of time scales from semidiurnal to seasonal
in order to quantify effects caused by the forcing factors of tidal mixing, freshwater input, and wind. Initial results indicate
that water density in the loch is controlled (to a major degree) by the freshwater input from runoff from the local catchment
area and from freshwater entering on the flood tide from the Clyde Estuary. It is estimated that during winter periods the
high freshwater flows from the rivers Leven and Clyde into the Clyde Estuary account for up to 75% of the freshwater creating
the density structure in the loch. Analysis of long-term dissolved oxygen data reveals that major bottom water renewals occurred
between July and January in the years 1987–1994. Major bottom water dissolved oxygen renewals have a general trend but during
the year sporadic renewals can take place due to abnormal dry spells increasing the density of the water entering from the
Clyde, or consistently strong winds from the north reducing stratification in the loch and producing better mixed conditions.
Velocities vary spatially, with the highest velocities of up to 0.6 m s–1 being associated with the velocity jet effect at the constriction at the sill of the loch. Observed near-surface mid-loch
velocities increased as the vertical density gradients in the upper layers increased. This indicates for the observed conditions
that increased stratification in the upper layers inhibits the entrainment rate and hence rate of gain of thickness of the
wind-driven surface layer, resulting in increased surface velocities for a given wind speed and direction. The main flow is
concentrated in the upper 10 m and velocities below 10 m are low. Observed mean spring tide surface velocities are on average
30% greater than mean neap tide surface velocities.
Received: 22 May 1995 · Accepted: 23 August 1995 相似文献