Topic
Groundwater flow
About: Groundwater flow is a research topic. Over the lifetime, 13134 publications have been published within this topic receiving 269774 citations.
Papers published on a yearly basis
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TL;DR: The scale of the problem in terms of population exposed to high As concentrations is greatest in the Bengal Basin with more than 40 million people drinking water containing ‘excessive’ As as mentioned in this paper.
6,741 citations
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01 Jan 1993TL;DR: In this paper, a comprehensive and quantitative approach to the study of groundwater quality is presented in order to predict what the effect of present-day human activities will be on that scale.
Abstract: Groundwater geochemistry is an interdisciplinary science concerned with the chemistry in the subsurface environment. The chemical composition of groundwater is the combined result of the quality of water that enters the groundwater reservoir and reactions with minerals and organic matter of the aquifer matrix may modify the water quality. Apart from natural processes as controlling factors on the groundwater quality, in recent years the effect of pollution, such as nitrate from fertilizers and acid rain, also influences the groundwater chemistry. Due to the long residence time of groundwater in the invisible subsurface environment, the effect of pollution may first become apparent tens to hundreds of years afterwards. A proper understanding of the processes occurring in aquifers is required in order to predict what the effect of present day human activities will be on that scale. This book presents a comprehensive and quantitative approach to the study of groundwater quality. Practical examples of application are presented throughout the text.
4,767 citations
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TL;DR: In this paper, three types of flow systems may occur in a small basin: local, intermediate, and regional, and the higher the topographic relief, the greater the importance of the local systems.
Abstract: Theoretically, three types of flow systems may occur in a small basin: local, intermediate, and regional. The local systems are separated by subvertical boundaries, and the systems of different order are separated by subhorizontal boundaries. The higher the topographic relief, the greater is the importance of the local systems. The flow lines of large unconfined flow systems do not cross major topographic features. Stagnant bodies of groundwater occur at points where flow systems meet or branch. Recharge and discharge areas alternate; thus only part of the basin will contribute to the baseflow of its main stream. Motion of groundwater is sluggish or nil under extended flat areas, with little chance of the water being freshened. Water level fluctuations decrease with depth, and only a small percentage of the total volume of the groundwater in the basin participates in the hydrologic cycle.
1,430 citations
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TL;DR: A review of methods that are based on groundwater-level data is presented in this article, where the theory underlying the methods is explained and examples from the literature are used to illustrate applications of the different methods.
Abstract: Accurate estimation of groundwater recharge is extremely important for proper management of groundwater systems. Many different approaches exist for estimating recharge. This paper presents a review of methods that are based on groundwater-level data. The water-table fluctuation method may be the most widely used technique for estimating recharge; it requires knowledge of specific yield and changes in water levels over time. Advantages of this approach include its simplicity and an insensitivity to the mechanism by which water moves through the unsaturated zone. Uncertainty in estimates generated by this method relate to the limited accuracy with which specific yield can be determined and to the extent to which assumptions inherent in the method are valid. Other methods that use water levels (mostly based on the Darcy equation) are also described. The theory underlying the methods is explained. Examples from the literature are used to illustrate applications of the different methods.
1,080 citations
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25 Dec 1991
TL;DR: This second edition is extensively revised throughout with expanded discussion of modeling fundamentals and coverage of advances in model calibration and uncertainty analysis that are revolutionizing the science of groundwater modeling.
Abstract: This second edition is extensively revised throughout with expanded discussion of modeling fundamentals and coverage of advances in model calibration and uncertainty analysis that are revolutionizing the science of groundwater modeling. The text is intended for undergraduate and graduate level courses in applied groundwater modeling and as a comprehensive reference for environmental consultants and scientists/engineers in industry and governmental agencies. * Explains how to formulate a conceptual model of a groundwater system and translate it into a numerical model * Demonstrates how modeling concepts, including boundary conditions, are implemented in two groundwater flow codes-- MODFLOW (for finite differences) and FEFLOW (for finite elements) * Discusses particle tracking methods and codes for flowpath analysis and advective transport of contaminants * Summarizes parameter estimation and uncertainty analysis approaches using the code PEST to illustrate how concepts are implemented * Discusses modeling ethics and preparation of the modeling report * Includes Boxes that amplify and supplement topics covered in the text * Each chapter presents lists of common modeling errors and problem sets that illustrate concepts
1,047 citations