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Showing 1 to 20 of 21 for “"karst aquifer"”.
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Modeling karst aquifer response to rainfall
… conductivity and potential gradient in a karst aquifer system. Rainfall excess in the form of potential energy from sinkhole sub-basins is input to element nodes and routed through a one-dimensional finite-element mesh to the karst spring represented by the last node in the finite element …
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Simulation Modeling of Karst Aquifer Conduit Evolution and Relations to Climate
ABSTRACT Karst regions of the world that receive relatively similar amounts of precipitation display a wide variety of landscapes. It has been suggested (Groves and Meiman, 2005) that climates exhibiting larger discrete storm events have more dissolving power and consequently higher rates of …
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Investigating Telogenetic Karst Aquifer Processes and Evolution in South-Central Kentucky, U.S., Using High-Resolution Storm Hydrology and Geochemistry Monitoring
… hydrological and geochemical characteristics of karst aquifers in different settings; however, telogenetic karst aquifer processes remain poorly understood. In south-central Kentucky, the iconic Lost River Cave and Valley represents a large, complex telogenetic karst drainage basin with a series …
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Analysis of Effects of Urbanization on Spring Geochemistry and Sediment for a Karst Aquifer in Valley Creek Basin, Chester County, Pennsylvania
… County, southeastern Pennsylvania, is an urban karst system. Four springs within the Elbrook Formation and two springs in the Ledger Dolomite have been monitored for suspended sediment, baseflow water chemistry, and storm response. Data from previous studies at two rural sites, Nolte in …
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Hydrogeological investigation of the Naukluft mountains, southwest Namibia
… Nama Group, aged 550 Ma. In this study, three aquifers are characterized within the study area. First, is the Naukluft Karst Aquifer which is fractured and karstified, and partly underlies the surface run-off catchments of the Tsauchab and Tsondab ephemeral rivers; second is the Nama Aquifer, …
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A Quantitative Analysis of Interstitial Fluid-Chemistry and Limestone Dissolution Rates Within the Clastic Sediment of a Karst Aquifer Conduit, Mammoth Cave, Kentucky
<p>Many active stream conduits within karst aquifers transport and deposit non-carbonate, clastic sediment. However, little is known about how these sediments impact conduit development and enlargement rates. For example, can dissolution take place at the sediment/bedrock interface beneath a …
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ΟΙ ΥΔΡΟΓΕΩΛΟΓΙΚΕΣ ΣΥΝΘΗΚΕΣ ΤΩΝ ΚΑΡΣΤΙΚΩΝ ΚΑΙ ΝΕΟΓΕΝΩΝ ΣΥΣΤΗΜΑΤΩΝ ΤΗΣ ΛΕΚΑΝΗΣ ΜΟΛΑΩΝ (ΛΑΚΩΝΙΑ)
… HORST, PLYTRA GRABEN. THERE WERE RECOGNISED FOUR KARSTIC EROSIONAL SURFACES. THE GEOLOGIC FORMATIONS OUTCROPPING IN THE MOLAI AREA ARE THE FOLLOWING: A) PHYLLITE-QUARTZITE SERIES, B) TYROS BEDS, C) TRIPOLITSA LIMESTONES, D) OLONOS ZONE, E) PELAGONIAN ZONE, F) THIC NEOGENE SEDIMENTS, THE EQUATION …
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Atrazine Contamination and Suspended Sediment Transport within Logsdon River, Mammoth Cave, Kentucky
Understanding the potential for karst aquifer contamination by sediment-sorbed pesticides is important for cave conservation efforts in agricultural landscapes. Flow rate, water quality parameters and suspended sediment concentrations were measured in Logsdon River, a ~10km karst conduit within the …
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Analyzing a 10-Year Cave Drip Record in James Cave, Virginia: Implications for Storage and Recharge in Shallow Appalachian Karst Systems
Karst aquifers, characterized by soluble rocks such as limestone and dolostone, provide drinking water to 20-25% of the world's population and are thus critical global water sources. However, recent work suggests that rapid alteration of karst aquifers due to the impact of climate change on …
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Delineating contributing areas for karst springs using NEXRAD data and cross-correlation analysis
… on spring discharge and precipitation data in karst aquifer basins has been used for many years to develop a conceptual understanding of an aquifer and estimate aquifer properties. However, to this point, the application of these processes has relied on gaged precipitation at discrete …
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ΑΣΤΑΘΗΣ ΡΟΗ ΣΕ ΚΑΡΣΤΙΚΑ ΥΔΡΟΦΟΡΑ ΣΤΡΩΜΑΤΑ ΜΕ ΤΗ ΜΕΘΟΔΟ ΤΩΝ ΠΕΠΕΡΑΣΜΕΝΩΝ ΣΤΟΙΧΕΙΩΝ
THE GROUNDWATER FLOW IN A CONFINED KARST AQUIFER IS STUDIED BY THE MODEL OF DOUBLE POROSITY. THIS IS A CONTINUOUS MODEL BUT IT TAKES INTO ACCOUNT THE HETEROGENEITY OF POROUS MEDIA. IT IS ALSO ASSUMED THAT IN KARST AQUIFERS THE FLOW CAN BE BEYOND THE UPPER LIMIT OF THE VALIDITY OF DARCY'S LAW. THE …
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Evaluating the Effectiveness of Regulatory Stormwater Monitoring Protocols on Groundwater Quality in Urbanized Karst Regions
… the United States today, particularly in urban karst settings. In these settings, the use of karst features and injection wells for stormwater management results in virtually untreated water being directed into the karst aquifer. Currently, no policies exist specifically to provide water quality …
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Epikarst control on flow and storage at James Cave, VA: an analog for water resource characterization in Shenandoah Valley karst
Karst aquifers host significant water supplies but are easily contaminated because highly conductive inlets can rapidly transmit water to depth. The epikarst, which is the region of vegetation, soil, and weathered bedrock above karst aquifers, is a critical zone as it regulates the quantity and …
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Analysis of Hydrologic and Geochemical Time Series Data at James Cave, Virginia: Implications for Epikarst Influence on Recharge
Karst aquifers are productive groundwater systems around the world, supplying approximately 25% of the world's drinking water. However, they are highly vulnerable to contamination due to rapid groundwater transit in the transmission zone (KWI 2006). The epikarst, also known as the subcutaneous …
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How Distance from Groundwater Affects the Water Status of Trees at San Marcos Springs
… and the role of landscape topography on karst aquifer freshwater supplies is still poorly understood. To gain perspective on this question, I conducted a study at a site where the depth of a shallow groundwater table was indicated by the water level of a spring-fed lake and the distance …
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Seasonal Effects on the Geochemical Evolution of the Logsdon River, Mammoth Cave, Kentucky
… Spring drainage basin within the Mammoth Cave karst aquifer of south-central Kentucky. This spatial survey of nearly 10 km of continuous base-level conduit included seasonal sampling of carbon dioxide partial pressures (Pco2)> dissolved ions, and saturation indices for calcite (SIcal). The …
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Cave air and dripwater variability in Cathedral Caverns, Alabama
… by: (i) a strong coupling between the timing of karst aquifer recharge (winter) and increased dripwater flow rates, (ii) cave dripwater δ18O (-5.7‰ (±0.2)) and δD (-32.1‰ (±2.6)) being similar to winter rainwater (-5.1‰ (±1.4) for δ18O and -27.8‰ (±15.1) for δD) collected at nearby Tuscaloosa, …
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Geographic Information System Methodologies to Evaluate Relationships Between Land use and Groundwater Quality in South Central Kentucky
… for a holistic approach to the study of karst groundwater contamination. While karst groundwaters supply water to a large percentage of the earth's population, its complex environments often have lacked the scientific examination and conservation measures typical of non-karst regions. In …
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Using Cesium 137 to Understand Recent in Cave Sedimentation in the Tongass National Forest, Southeast Alaska
Removal of vegetation and subsequent erosion in karst regions such as central Kentucky or southeastern Alaska often leads to increased sedimentation in karst features such as caves and dolines. This sedimentation can impact the ground water by altering flow paths and the bio-geochemistry of the …
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