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Enviroscan Ukrainian Institute of Speleology and Karstology


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Community news

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 water-table divide is see divide.?

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.
See all featured articles
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 groundwater-flow (Keyword) returned 68 results for the whole karstbase:
Showing 61 to 68 of 68
Karstic behaviour of groundwater in the English Chalk, 2006,
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Maurice L. D. , Atkinson T. C. , Barker J. A. , Bloomfield J. P. , Farrant A. R. , Williams A. T. ,
SummaryAlthough the Chalk is only weakly karstified, tracer testing from stream sinks has demonstrated groundwater flow velocities comparable to those observed in highly karstic aquifers. Field survey of surface karst features in the catchments of the Pang and Lambourn rivers in southern England demonstrates the importance of overlying and adjacent Palaeogene strata in the development of karst features. Tracer techniques employed within the catchments enable further characterisation of the range and connectivity of solutional voids in this area of the Chalk, and allow assessment of the relative importance of different mechanisms of contaminant attenuation. Quantitative tracer test results suggest that groundwater flow may be through a complex combination of small conduits, typically 10-1000 mm in diameter, and more laterally extensive fissures with apertures of 1-50 mm. Evidence of connectivity between conduits and fissures suggest that in areas of the Chalk with rapid groundwater flow, fissures supplying abstraction boreholes may be connected to karst conduit networks with low potential for contaminant attenuation

Strontium isotope characterization and major ion geochemistry of karst water flow, Shentou, northern China, 2006,
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Wang Yanxin, Guo Qinghai, Su Chunli, Ma Teng,
SummaryKarst water is the most important source of water supply for Shanxi province, northern China. The Shentou springs are representative of the 19 major karst springs at Shanxi. The total area of the Shentou karst water system is 5316 km2, the Middle Ordovician limestone being its major karst aquifer. In this study, data about the strontium isotope geochemistry and major ion hydrochemistry were analyzed to understand the flow patterns and hydrogeochemical processes of karst water at Shentou. The contour map of TDS value of karst water and that of Sr concentration are similar, showing the general tendency of increase from the northern, western and southern boundary to the discharge area. The average values of 87Sr/86Sr ratios of karst water decrease from recharge (0.7107) to discharge area (0.7102), evolving towards those of limestone hostrocks. Comparison of 87Sr/86Sr ratios with Sr content suggests that isotopic compositions of some karst water samples from the recharge and flow through area should be the result of interaction between aquifer limestone matrix and strontium-poor recharge waters of meteoric origin. However, for samples from the discharge area that are plotted above the mixing line, mixing with groundwater in the Quaternary aquifers with high 87Sr/86Sr ratios may be another factor controlling Sr isotope chemistry. Two major groundwater flow paths were discerned from hydrogeological and geochemical data. Along both flow paths, the 87Sr/86Sr ratios of karst water show a general tendency of decrease. Geochemical modeling of the major ion geochemistry of karst water using PHREEQC also indicates that the chemistry of springs should be affected by the incorporation of groundwater in Quaternary aquifer. The effect of the mixing action on the spring hydrochemistry in flow path 1 is more remarkable than that in flow path 2, according to different mixing ratios in both paths (30% in flow path 1 and 5% in flow path 2)

Unusual Phosphate Concretions Related to Groundwater Flow in a Continental Environment, 2006,
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Thiry Medard, Galbois Jean, Schmitt Jean Michel,
Occurrence of phosphate cemented-sandstone concretions in alluvial sand containing archaeological layers implies that they have formed during the last 2000 years. Morphology and petrography of the concretions indicates a relationship with groundwater cementation. The phosphate cement of the concretions consists of concentric isopachous aureoles, about 10 {micro}m thick, that wrap the detrital grains. Aureoles are formed of collophane, the cryptocrystalline or amorphous variety of hydroxyapatite. Geochemical modeling indicates that the apatite cement likely results from the leaching of a preexisting phosphate deposit (bones?) in an acidic soil environment and the precipitation of dissolved phosphate under pH control at the mixing zone of down-moving soil-water with the calcite-saturated groundwater

Mechanical stratigraphic controls on fracture patterns within carbonates and implications for groundwater flow, 2006,
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Cooke Ml, Simo Ja, Underwood Ca, Rijken P,
Groundwater flow in low matrix-permeability carbonate rocks is largely controlled by fracture networks. The stratigraphic features that control fracture initiation and termination within a sequence of sedimentary rock strata define the mechanical stratigraphy of the sequence. We investigate the effectiveness of various types of stratigraphic horizons in terminating opening-mode fractures in two different carbonate rock sequences: a relatively homogeneous dolomite sequence, in Door County, WI and an interbedded chalk and marl sequence within the Austin Chalk, TX. Additionally, we present analog and numerical modeling results that delineate the specific mechanisms that facilitate fracture termination. The combination of model results and empirical relationships between observed sedimentary features and mechanical stratigraphy shows: (1) fractures terminate at weak contacts (e.g. thin organic layers), shallowly buried contacts or thick fine-grained units adjacent to thin fractured beds, (2) fractures propagate across strong contacts (e.g. intracycle contacts between different lithology) and thin fine-grained units adjacent to thick fractured beds and (3) fractures step-over at moderate strength contacts. We use these guidelines to predict fracture network from sedimentary stratigraphy by qualitatively assessing the mechanical stratigraphy of a portion of the relatively complex Cretaceous shelf-margin sequence at Sant Corneli, Spain. This predictive demonstration illustrates the utility of assessing the mechanical stratigraphy of subsurface strata within which fractures are not directly observable. We conclude that for a variety of carbonate mechanical stratigraphic sequences, dominant fluid flow characteristics, such as horizontal high flow zones and flow compartmentalization, can be evaluated using fracture spacing and connectivity within fracture networks that is predicted from sedimentary stratigraphy. Although the resulting heterogeneous flow networks do not rely on every fracture present, they are highly dependent on the mechanical stratigraphy

On the importance of geological heterogeneity for flow simulation, 2006,
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Eaton Tt,
Geological heterogeneity is recognized as a major control on reservoir production and constraint on many aspects of quantitative hydrogeology. Hydrogeologists and reservoir geologists need to characterize groundwater flow through many different types of geological media for different purposes. In this introductory paper, an updated perspective is provided on the current status of the long effort to understand the effect of geological heterogeneity on flow using numerical simulations. A summary is given of continuum vs. discrete paradigms, and zonal vs. geostatistical approaches, all of which are used to structure model domains. Using these methods and modern simulation tools, flow modelers now have greater opportunities to account for the increasingly detailed understanding of heterogeneous aquifer and reservoir systems.One way of doing this would be to apply a broader interpretation of the idea of hydrofacies, long used by hydrogeologists. Simulating flow through heterogeneous geologic media requires that numerical models capture important aspects of the structure of the flow domain. Hydrofacies are reinterpreted here as scale-dependent hydrogeologic units with a particular representative elementary volume (REV) or structure of a specific size and shape. As such, they can be delineated in indurated sedimentary or even fractured aquifer systems, independently of lithofacies, as well as in the unlithified settings in which they have traditionally been used. This reconsideration of what constitutes hydrofacies, the building blocks for representing geological heterogeneity in flow models, may be of some use in the types of settings described in this special issue

Influence of depositional setting and sedimentary fabric on mechanical layer evolution in carbonate aquifers, 2006,
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Graham Wall Brita R. ,
Carbonate aquifers in fold-thrust belt settings often have low-matrix porosity and permeability, and thus groundwater flow pathways depend on high porosity and permeability fracture and fault zones. Methods from sedimentology and structural geology are combined to understand the evolution of fracture controlled flow pathways and determine their spatial distribution. Through this process bed-parallel pressure-solution surfaces (PS1) are identified as a fracture type which influences fragmentation in peritidal and basinal carbonate, and upon shearing provides a major flow pathway in fold-thrust belt carbonate aquifers. Through stratigraphic analysis and fracture mapping, depositional setting is determined to play a critical role in PS1 localization and spacing where peritidal strata have closer spaced and less laterally continuous PS1 than basinal strata. In the peritidal platform facies, units with planar lamination have bed-parallel pressure-solution seams along mudstone laminae. In contrast, burrowed units of peritidal strata have solution seams with irregular and anastamosing geometries. Laminated units with closely spaced bed-parallel solution seams are more fragmented than bioturbated units with anastamosing solution seams. In the deeper-water depositional environment, pelagic settling and turbidity currents are the dominant sedimentation processes, resulting in laterally continuous deposits relative to the peritidal platform environment. To quantify the fracture patterns in the basinal environment, mechanical layer thickness values were measured from regions of low to high bed dip. The results define a trend in which mechanical layer thickness decreases as layer dip increases. A conceptual model is presented that emphasizes the link between sedimentary and structural fabric for the peritidal and basinal environments, where solution seams localize in mud-rich intervals, and the resulting pressure-solution surface geometry is influenced by sedimentary geometry (i.e., stacked fining upward cycles, burrows, planar laminations). In both facies types, laterally continuous PS1 can behave as mechanical layer boundaries. As layer-parallel slip increases to accommodate shear strain in the fold-thrust belt, more PS1 behave as mechanical layer boundaries

Modeling complex flow in a karst aquifer, 2006,
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Quinn John J. , Tomasko David, Kuiper James A. ,
Carbonate aquifers typically have complex groundwater flow patterns that result from depositional heterogeneities and post-lithification fracturing and karstification. Various sources of information may be used to build a conceptual understanding of flow in the system, including drilling data, well tests, geophysical surveys, tracer tests, and spring gaging. These data were assembled to model flow numerically in Germany's Malm Formation, at a site where water disappears from the beds of ephemeral stream valleys, flows through conduit systems, and discharges to springs along surface water features. Modeling was performed by using a finite-difference approach, with drain networks, representing the conduit component of flow, laced throughout the porous medium along paths inferred on the basis of site data. This approach represents an improvement over other karst models that attempt to represent a conduit by a single, specialized model node at the spring location or by assigning a computationally problematic extremely high permeability to a zone. By handling the conduit portion of this mixed-flow system with drains, a realistic, interpretive flow model was created for this intricate aquifer

Evidence for hydraulic heterogeneity and anisotropy in the mostly carbonate Prairie du Chien Group, southeastern Minnesota, USA, 2006,
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Tipping Robert G. , Runkel Anthony C. , Alexander Jr. E. Calvin, Alexander Scott C. , Green Jeffery A. ,
In southeastern Minnesota, Paleozoic bedrock aquifers have typically been represented in groundwater flow simulations as isotropic, porous media. To obtain a more accurate hydrogeologic characterization of the Ordovician Prairie du Chien Group, a new approach was tested, combining detailed geologic observations, particularly of secondary porosity, with hydraulic data. Lithologic observations of the depositional and erosional history of the carbonate-dominated bedrock unit constrained characterization of both primary (matrix) and secondary porosity from outcrops and core. Hydrostratigraphic data include outcrop and core observations along with core plug permeability tests. Hydrogeologic data include discrete interval aquifer tests, borehole geophysics, water chemistry and isotope data, and dye trace studies. Results indicate that the Prairie du Chien Group can be subdivided into the Shakopee aquifer at the top, consisting of interbedded dolostone, sandstone and shale, and the underlying Oneota confining unit consisting of thickly bedded dolostone. The boundary between these two hydrogeologic units does not correspond to lithostratigraphic boundaries, as commonly presumed. Groundwater flow in the Shakopee aquifer is primarily through secondary porosity features, most commonly solution-enlarged bedding planes and sub-horizontal and vertical fractures. Regional scale preferential development of cavernous porosity and permeability along specific stratigraphic intervals that correspond to paleokarst were also identified, along with a general depiction of the distribution of vertical and horizontal fractures. The combination of outcrop and core investigations, along with borehole geophysics, discrete interval aquifer tests, water chemistry and isotope data and dye trace studies show that the Prairie du Chien Group is best represented hydrogeologically as heterogeneous and anisotropic. Furthermore, heterogeneity and anisotropy within the Prairie du Chien Group is mappable at a regional scale (> 15,000 km2)

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