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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 proto-cave is natural void that links a potential input point and an output point within an aquifer, but which is still too small to be entered by man [9].?

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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 carbonate-aquifer (Keyword) returned 40 results for the whole karstbase:
Showing 31 to 40 of 40
Persistence of 17 {beta}-Estradiol in Water and Sediment-Pore Water from Cave Streams in Central Missouri, 2005, Peterson Eric W. , Wicks Carol M. , Kelley Cheryl A. ,
Concentrations less than 10 ng/L of 17 {beta}-estradiol (E2), a natural estrogen, have been linked to adverse health effects in fish, including skewed sex distributions, reproductive failure, and organ impairment. The persistence of E2 in carbonate aquifer systems is not well documented. Water and sediment from cave streams within the Ozark Plateau of Missouri, USA, were collected and analyzed for E2. The persistence of E2 in the water was examined in two separate experiments, in which the holding temperatures (20{degrees}C vs. 4{degrees}C), bottle type, exposure to light, and filtration were varied. During two trials, no statistical difference was observed in the concentration of E2, suggesting that E2 is stable within the water. The fate of E2 was also examined in sediment-pore water collected from the cave streams in two independent trials. In trial 1, a significant decrease in E2 was noted over the 29 days of the experiment. However, in trial 2, no change in E2 concentration was observed. The results indicate that E2 is relatively stable in cave stream water and may persist in the sediment

On 226Ra and 222Rn concentrations in the brackish waters of coastal aquifers: lab-investigations and confirmation in the carbonate aquifer of Brindisi (Italy), 2005, Spizzico M. , Sciannamblo D. ,

On Ra-226 and Rn-222 concentrations in the brackish waters of coastal aquifers: lab-investigations and confirmation in the carbonate aquifer of Brindisi (Italy), 2005, Spizzico M. , Sciannamblo D. ,
The ground waters circulating in the Apulian mesozoic carbonate aquifer, of coastal type, show high concentrations of Rn-222 everywhere. Considering their variation during the different phases of a hydrological year, such high concentration values can reach activity of 20 Bq/L, in the more internal zones of the aquifer. Moreover, it is often observed that, in correspondence of wells and springs nearest the coast, the concentrations of radioactive gas reach values greater than 400 Bq/L and vary considerably during the course of a day and with withdrawals. The research carried out over the last few years, has confirmed that Ra-226 and Rn-222 concentrations in the karst groundwater of Apulia, are mainly related to the occurrence of 'Terra Rossa' inside the aquifer and the capacity of these paleosols to fix the salts of Ra-226 coming from the dissolution of the calcareous and calcareous-dolomitic rocks. This paper shows the results of the analysis performed to define Rn-222 increase in the brackish waters that come in contact with carbonate rocks and 'terra rossa'. It also indicates the results of surveys performed in a coastal zone with well-known hydrogeological features. The controls performed during one hydrological year, have confirmed the relationships between the salt content of the ground waters and the enrichment of Rn-222 and have highlighted that the manner of increase of this radioisotope is related to cases of ionic exchange and adsorption regulated by the dynamics of marine intrusion

Water quality improvement program effectiveness for carbonate aquifers in grazed land watersheds, 2005, Boyer Dg,
Water quality indicators of two agriculturally impacted karst areas in southeastern West Virginia were studied to determine the water quality effects of grazing agriculture and water quality trends following initiation of water quality improvement programs. Both areas are tributaries of the Greenbrier River and received funding for best management practices under the President's Initiative for Water Quality and then under the Environmental Quality Incentives Program (EQIP). After 11 years of study there was little evidence to suggest that water quality improved in one area. Three and a half years of study in the other area showed little evidence of consistent water quality improvement under EQIP. Lack of consistent water quality improvement at the catchment scale does not imply that the voluntary programs were failures. Increased livestock numbers as a result of successful changes in forage management practices may have overridden water quality improvements achieved through best management practices. Practices that target well defined contributing areas significantly impacting aquifer water quality might be one way to improve water quality at catchment scales in karst basins. For example, a significant decrease in fecal coliform concentrations was observed in subterranean drainage from one targeted sinkhole after dairy cattle were permanently excluded from the sinkhole

Hydrogeochemical balance sheet of natural and anthropogenic impacts onto Orleans valley karstic network performed with major elements : the 'dynamic confinement' model quantification, 2006, Le Borgne Francois, Treuil Michel, Joron Jean Louis, Lepiller Michel,
The Orleans valley aquifer comprises both the alluvia of the Loire river and its underlying calcareous stratum. This aquifer is fed by river recharge, thanks to a substantial karstic network in its calcareous part. The main outlets of the aquifer are the Loiret springs, including the famous 'le Bouillon' spring. As a result, entries and exits of Orleans valley watertable make a natural observatory, allowing study of the transit of the chemical species inside the aquifer. Since 1997, this natural observatory has been improved with the installation of 52 piezometers (37 in the alluvial aquifer and 15 in the carbonate aquifer) within an alluvial quarry located in the middle of Orleans valley. Tracer experiments, carried out in this extended observatory, have shown that the porous calcareous and alluvial part of the aquifer constitute a 'dynamically confined system'. As a result, the hydrochemical input of the porous domain of the aquifer to the karstic flow must be negligible. The aim of this study is to confirm this theory with the use of major elements as large-scale temporal and spatial tracers of these exchanges. At 'le Bouillon' karstic spring, the Na, K, Mg2, Cl- and SO42- concentrations are closely correlated to those of the Loire river if a 3-4 day time lag is considered. This indicates a quasi-conservative transit of these elements in the karst. Conversely, calcite dissolution accompanying the organic matter biodegradation induces significant enrichments in Ca2, HCO3- and NO3- (mean annual concentrations of which are, respectively, 27.0, 87.8 and 4.9 mg.L-1 in the Loire river and 37.3, 127 et 7.3 mg.L-1 at 'le Bouillon' spring). After fertiliser spreading, the alluvial waters are highly enriched in NO3-, Cl-, SO42- (respectively 67.2, 24.0, 57.5 mg.L-1) compared to the Loire river (respectively 5.5, 12.7, 17.5 mg.L-1). The anthropogenic input is insignificant for Na, of which the average concentration in the alluvial watershed (11.7 mg.L-1) remains close to the Loire river (12.9 mg.L-1). The alluvial watershed is depleted in K (1.3 mg.L-1) with respect to the Loire river (3.7 mg.L-1) and correlatively enriched in Mg2 (17.0 mg.L-1 against 5.0 mg.L-1). High major element concentrations are measured in several calcareous piezometers confirming that vertical flows occur between the alluvial and calcareous parts of the aquifer. Furthermore, enrichment heterogeneity in those two strata is induced by a dynamic redistribution, with no significant leaching of anthropogenic inputs which were previously homogeneously spread. This redistribution is pulsed by ascents of the Loire river, impacts of which on the watershed are clearly identified on Mg/K-Na/K diagrams showing a main K {leftrightarrows} Mg exchange between Loire water and clays minerals. Taking into account average K and Mg concentrations in the different parts of Orleans valley's watershed, the volume of porous aquifer water brought to the karstic network flow mean estimated is 2.4 % of the total volume which transits between the Loire and the 'le Bouillon' spring, showing the dynamic confining action of the aquifer porous domain. Taking into account more precisely seasonal river Loire and spring composition variation, these inputs can be more precisely established : 1.6% during winter and 1.2% during summer at 'Le Bouillon' spring; 2.4% during winter and 3.9% during summer at 'La Pie' spring. But such a weak global contribution of the porous domain accounts for 10% nitrate composition of the karstic springs. Seasonal spring nitrate composition balance is clearly explained by 60% river Loire, 30 % organic matter oxydation - carbonate dissolution and 10% porous domain inputs during winter, and 30% river Loire, 60% organic matter, - carbonate dissolution and 10% porous domain inputs. Same calcium mass balance calculations point out the necessity of CO2 winter complementary input by local rain fall penetrations

Contribution of stable isotopes to the understanding of the unsaturated zone of a carbonate aquifer (Nerja Cave, southern Spain), 2006, Carrasco F, Andreo B, Linan C, Mudry J,
We analysed the stable isotopes (18O and 2H) of rainwater and drip water within a cave (Nerja Cave) located in the unsaturated zone of a carbonate aquifer. Rainfall is more abundant and presents lower isotopic content in winter, while the volume of drip water is greater and its isotopic content is lower in summer. The flow analysis of 18O through the unsaturated zone confirms the seasonal lag between rainfall and the appearance of drip water in the cave and reveals that the unsaturated zone of the aquifer, in the sector of the cave, behaves like an inertial system with a strong capability to modulate the input signal. To cite this article: F. Carrasco et al., C. R. Geoscience 338 (2006)

Textural and stratigraphic controls on fractured dolomite in a carbonate aquifer system, Ocala limestone, west-central Florida, 2006, Gaswirth Sb, Budd Da, Crawford Br,
The Late Eocene Ocala Limestone is part of the Upper Floridan Aquifer, and in west-central Florida the Ocala forms a subregional semi-confining unit that separates underlying and overlying highly transmissive zones. In portions of the same area, the lower half of the Ocala is dolomitized and fractures are observed in cores. Where present, the fractures should locally enhance the hydraulic conductivity of the dolomite and could enhance vertical leakage through the semi-confining Ocala interval.Triaxial strength tests and Brazilian Disc tensile tests were conducted on a suite of 2.5-cm diameter dolomite core plugs from five boreholes. Samples were texturally subdivided on the basis of degree of induration into three general categories: friable sucrosic dolomite with high porosity, moderately indurated dolomite with intermediate porosity, and tightly indurated dolomite with low porosity. Results indicate elevated cohesion magnitude and tensile strength as the degree of induration increases and secondarily as abundance of moldic porosity decreases. Sucrosic and moderately indurated dolomites are most likely to fracture due to their low cohesion strength, followed by tightly indurated dolomites with high moldic porosity. Tightly indurated dolomite with little or no moldic porosity is the least likely to fracture.Degree of dolomite induration is a function of the lime precursor's depositional fabric. Thus, combining strength data with known stratigraphic patterns in depositional textures allows for prediction of mechanical units and fractured horizons in the Ocala dolomites, and provides insight into regions of potentially increased hydraulic conductivity

Influence of depositional setting and sedimentary fabric on mechanical layer evolution in carbonate aquifers, 2006, 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, 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

Contributory area definition for groundwater source protection and hazard mitigation in carbonate aquifers, 2007, Gunn J. ,
Carbonate aquifers provide important sources of potable water but are known to be particularly prone to pollution owing to rapid transfer of pollutants from the surface to springs or boreholes. Source protection zones and groundwater vulnerability maps are commonly used to mitigate against the pollution hazard but cannot be applied simplistically to carbonate aquifers, which are usually highly heterogeneous with overlapping groundwater divides that may vary with water levels. Divergent flow and disjunct contributory areas provide further complexity. Under these conditions, water-tracing experiments, repeated under different flow conditions, are the only tool capable of identifying those areas that contribute recharge to a particular source. Examples of water pollution affecting disjunct and overlapping source contributory areas are presented from the Waitomo area (New Zealand), Cuilcagh Mountain (Ireland) and the Peak District (UK). Source protection zones (SPZ), that have been defined by the Environment Agency in the Buxton area of the Peak District using equivalent porous medium models, are shown to be deficient. Further water-tracing experiments are essential if carbonate aquifers are to be adequately protected from pollution

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