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Speleology in Kazakhstan

Shakalov on 04 Jul, 2018
Hello everyone!   I pleased to invite you to the official site of Central Asian Karstic-Speleological commission ("Kaspeko")   There, we regularly publish reports about our expeditions, articles and reports on speleotopics, lecture course for instructors, photos etc. ...

New publications on hypogene speleogenesis

Klimchouk on 26 Mar, 2012
Dear Colleagues, This is to draw your attention to several recent publications added to KarstBase, relevant to hypogenic karst/speleogenesis: Corrosion of limestone tablets in sulfidic ground-water: measurements and speleogenetic implications Galdenzi,

The deepest terrestrial animal

Klimchouk on 23 Feb, 2012
A recent publication of Spanish researchers describes the biology of Krubera Cave, including the deepest terrestrial animal ever found: Jordana, Rafael; Baquero, Enrique; Reboleira, Sofía and Sendra, Alberto. ...

Caves - landscapes without light

akop on 05 Feb, 2012
Exhibition dedicated to caves is taking place in the Vienna Natural History Museum   The exhibition at the Natural History Museum presents the surprising variety of caves and cave formations such as stalactites and various crystals. ...

Did you know?

That clay marl is 1. a whitish, smooth, chalky clay. 2. a marl in which clay predominates.?

Checkout all 2699 terms in the KarstBase Glossary of Karst and Cave Terms

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KarstBase a bibliography database in karst and cave science.

Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
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Featured articles from other Geoscience Journals
Karst environment, Culver D.C.
Mushroom Speleothems: Stromatolites That Formed in the Absence of Phototrophs, Bontognali, Tomaso R.R.; D’Angeli Ilenia M.; Tisato, Nicola; Vasconcelos, Crisogono; Bernasconi, Stefano M.; Gonzales, Esteban R. G.; De Waele, Jo
Calculating flux to predict future cave radon concentrations, Rowberry, Matt; Marti, Xavi; Frontera, Carlos; Van De Wiel, Marco; Briestensky, Milos
Microbial mediation of complex subterranean mineral structures, Tirato, Nicola; Torriano, Stefano F.F;, Monteux, Sylvain; Sauro, Francesco; De Waele, Jo; Lavagna, Maria Luisa; D’Angeli, Ilenia Maria; Chailloux, Daniel; Renda, Michel; Eglinton, Timothy I.; Bontognali, Tomaso Renzo Rezio
Evidence of a plate-wide tectonic pressure pulse provided by extensometric monitoring in the Balkan Mountains (Bulgaria), Briestensky, Milos; Rowberry, Matt; Stemberk, Josef; Stefanov, Petar; Vozar, Jozef; Sebela, Stanka; Petro, Lubomir; Bella, Pavel; Gaal, Ludovit; Ormukov, Cholponbek;
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Your search for wellfield (Keyword) returned 4 results for the whole karstbase:
Regional groundwater flow model construction and wellfield site selection in a karst area, Lake City, Florida, 1999, Dufresne Dp, Drake Cw,
The city of Lake City is in the process of expanding their water supply facilities by 45 420 m(3) day(-1) (12 MGD) to meet future demands. One portion of wellfield site selection addressed here includes analysis of ambient groundwater quality and its potential for contamination. This study also addresses the potential impacts of groundwater withdrawals to existing legal users, wetlands, surface waters and spring flows. A regional groundwater flow model (MODFLOW) was constructed using existing hydrogeologic data from state and federal agencies in order to simulate the existing hydrologic conditions of this karst area and to predict withdrawal impacts. The model was calibrated by matching potentiometric surface maps and spring flows to within reasonable ranges. Drawdowns in the Floridan and surficial aquifers predicted by the model show minimal impacts to existing legal users and only a 5% reduction in the flow at Ichetucknee Springs ca 21 km (13 miles) away. Due to the karstic nature of the Floridan aquifer here, the equivalent-porous-medium flow model constructed would not be appropriate for contaminant transport modeling. The groundwater flow model is, however, appropriate to represent hydraulic heads and recharge/discharge relationships on a regional scale. (C) 1999 Elsevier Science B.V. All rights reserved

HJWFTAC: software for Hantush-Jacob analysis of variable-rate, multiple-extraction well pumping tests, 2002, Fleming Sw, Ruskauff Gj, Adams A,
Analytical well test solutions are a powerful approach to aquifer characterization and the parameterization of comprehensive numerical models. In addition, wellfield drawdown tests, which consist of coordinated pumping and data collection at a suite of monitoring and operating production wells, are of growing significance due to increasing pressures upon groundwater resources and the consequent management and planning requirement for superior hydrogeologic characterization of existing production wellfields. However. few pumping test analysis codes accommodate the multiple extraction wells involved, particularly for more sophisticated analytic aquifer test solutions. We present and demonstrate here a FORTRAN code for analysis of drawdown at a monitor well due to simultaneous variable-rate pumping at multiple independent production wells, which we developed in response to a need to refine an existing numerical, coupled groundwater/surface water resource management model, Spatial and temporal superposition are used to accommodate the typical operational properties of wellfield pumping tests, The software invokes the well-accepted Hantush-Jacob method for semiconfined or 'leaky' aquifers in a forward simulation procedure and effectively assumes homogeneity in applicable aquifer parameters (transmissivity, coefficient of storage, and leakance). Intended for both professionals and students, the code is widely applicable and straightforward to use as written. However, it can be modified with relative ease to use alternative well test solutions and/or formal inverse modeling techniques, or to accommodate spatial hydrogeologic variability. An application to a pumping test conducted in a karst limestone aquifer at the Cross Bar Ranch wellfield in Tampa Bay, Florida, demonstrates the utility of the software. (C) 2002 Elsevier Science Ltd. All rights reserved

Use of stable isotopes to quantify flows between the Everglades and urban areas in Miami-Dade County Florida, 2004, Wilcox W. M. , Sologabriele H. M. , Sternberg L. O. R. ,
An isotopic study was performed to assess the movement of groundwater for a site located in Miami-Dade County, Florida. The site encompasses portions of a protected wetland environment (northeast Everglades National Park) and suburban residential Miami, incorporating municipal pumping wells and lakes formed by rock mining. Samples of ground, surface, and rainwater were analyzed for their isotopic composition (oxygen-18 and deuterium). Various analytical and graphical techniques were used to analyze this data and two conceptual box models were developed to quantify flows between different regions within the site. Results from this study indicate that the aquifer underlying the study site (the Biscayne aquifer) is highly transmissive with the exception of two semi-confining layers of reduced hydraulic conductivity. Everglades surface water infiltrates into the aquifer and migrates east toward residential areas. In these urban areas, 'shallow' groundwater (above the deeper semi-confining layer) is substantially affected by urban rainfall while 'deep' groundwater (below the deeper semi-confining layer) maintains a composition similar to that of Everglades water. Rock mining lakes in the area provide 'breaks' in the semi-confining layers that allow for mixing of shallow and deep groundwater. As water travels eastward, municipal well intakes, screened to a depth below the deeper semi-confining layer, draw upon not only shallow urban water (predominantly comprised of urban rainfall) and lake water (having influences from both urban rainfall and Everglades water) but also deep water that originated in the Everglades. Results from one of the box models estimate that over 60% of the water being removed by municipal pumping originated in the Everglades. These conclusions suggest that Everglades water, both directly through deep groundwater flow and indirectly through mixing with rock-mining lakes, is being drawn into the operating municipal wellfield.

Assessing the Vulnerability of a Municipal Well Field to Contamination in a Karst Aquifer, 2005, Renken R. A. , Cunningham K. J. , Zygnerski M. R. , Wacker M. A. , Shapiro A. M. , Harvey R. W. , Metge D. W. , Osborn C. L. , Ryan J. N. ,
Proposed expansion of extractive lime-rock mines near the Miami-Dade County Northwest well field and Everglades wetland areas has garnered intense scrutiny by government, public, environmental stakeholders, and the media because of concern that mining will increase the risk of pathogen contamination. Rock mines are excavated to the same depth as the well field's primary producing zone. The underlying karst Biscayne aquifer is a triple-porosity system characterized by (1) a matrix of interparticle porosity and separate vug porosity; (2) touching-vug porosity that forms preferred, stratiform passageways; and, less commonly, (3) conduit porosity formed by thin solution pipes, bedding-plane vugs, and cavernous vugs. Existing ground-water flow and particle tracking models do not provide adequate information regarding the ability of the aquifer to limit the advective movement of pathogens and other contaminants. Chemical transport and colloidal mobility properties have been delineated using conservative and microsphere-surrogate tracers for Cryptosporidium parvum. Forced-gradient tests were executed by introducing conservative tracers into injection wells located 100 m (328 ft) from a municipal-supply well. Apparent mean advective velocity between the wells is one to two orders of magnitude greater than previously measured. Touching-vug, stratiform flow zones are efficient pathways for tracer movement at the well field. The effective porosity for a continuum model between the point of injection and tracer recovery ranges from 2 to 4 percent and is an order of magnitude smaller than previously assumed. Existing well-field protection zones were established using porosity estimates based on specific yield. The effective, or kinematic, porosity of a Biscayne aquifer continuum model is lower than the total porosity, because high velocities occur along preferential flow paths that result in faster times of travel than can be represented with the ground-water flow equation. Tracer tests indicate that the relative ease of contaminant movement to municipal supply wells is much greater than previously considered

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