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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. ...

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. ...

Speleology in Kazakhstan

Shakalov on 11 Jul, 2012
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 surface entry is an opening immediately at the land surface that permits infiltration to take place [16].?

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Chemistry and Karst, White, William B.
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Geochemical and mineralogical fingerprints to distinguish the exploited ferruginous mineralisations of Grotta della Monaca (Calabria, Italy), Dimuccio, L.A.; Rodrigues, N.; Larocca, F.; Pratas, J.; Amado, A.M.; Batista de Carvalho, L.A.
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
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Your search for groundwater discharge (Keyword) returned 34 results for the whole karstbase:
Showing 1 to 15 of 34
Hydrogeology of the Umm Er Radhuma aquifer, Saudi Arabia, with reference to fossil gradients, 1982, Bakiewicz W, Milne Dm, Noori M,
Much of North Africa and the Arabian peninsula, lying in the Saharan climate zone, are underlain by huge tabular sandstone and carbonate aquifers, ranging in age from Cambrian to Tertiary. These are often saturated with water of reasonable quality and form very valuable resources in an area often desperately short of water. The Palaeocene Umm Er Radhuma carbonate aquifer is one such formation which has been the subject of intensive recent investigation. The formation contains groundwater of a reasonable quality, has adequate transmission and storage characteristics and hence considerable potential for future development. The origin of the water in such aquifers is the subject of continuing controversy. It is not disputed that the water is moving under the influence of regional groundwater gradients but origins of these gradients are the subject of considerable argument. On the one hand, there are those who hold that the presently observed gradients are fossil remnants of conditions created by a much wetter climatic regime prevalent some thousands of years ago. Against this are those who maintain that the gradients, at least in part, reflect a present day system with groundwater discharge in approximate dynamic equilibrium with recharge. This paper examines the hydrogeology of a typical Middle Eastern formation of the disputed kind, the Umm Er Radhuma aquifer in Saudi Arabia, and, with the aid of analytical and numerical models, attempts to resolve the problem of the origin of the observed groundwater gradients and to discover the extent to which the past must influence present day plans for future development

Quaternary calcrete, silcrete and gypcrete duricrusts in Karinga Creek drainage system, central Australia, contain abundant late-stage diagnetic features. These indicate repeated episodes of dissolution, precipitation and mobilization of duricrust components in the landscape, following the initial development of the duricrust mantle. 'Mature' duricrust profiles incorporate assemblages of diagnostic textural features and fabrics that clearly indicate the extent of karstification during the past 27 000 years. Diagenetic features in the duricrusts permit recognition of the stages involved in vadose modifications of compositional, textural and morphological features and, hence, assessment of the impact of karst dissolution, precipitation and mobilization of duricrust components under prevailing environmental conditions. At landscape level, the continued development of secondary porosity-permeability zones in topographically elevated areas, and maintenance of effective topographic gradients for soil creep are considered essential for redistribution of duricrust components and lateral and vertical extension of karst features within the Quaternary duricrust mantle. Although developing over a comparatively short span of time, late-stage modification of the Quaternary duricrusts has important implications for evolution of Quaternary landscapes and distribution of groundwater discharge-recharge patterns. Accordingly, differential dissolution and reprecipitation within the duricrust profiles have progressively given way to development of karst solution pipes and cavities, with the latter now acting as effective conduits for recharge of local aquifers in the region

The study area is situated within the complex structure and karst system of the western Taurids. Basinwide interpretation of the structural features, each of which has great importance, will enlighten many complicated hydrogeologic problems encountered in the area. Thus, considering the previous views on the structural geology of the area, an interpretation of the structural and tectonic features of the study area by means of satellite images was undertaken, and based on the data gained, new approaches were suggested to solve the hydrogeological problems, in particular, determination of the recharge-discharge mechanisms of the Olukkopru and Dumanli karst springs, which are the most important karst groundwater discharge points in the region, has been attempted. Within the framework of this study, a tectonic-lineament map of a large area covering Eqirdir, Beysehir, and Sugla lakes at the north and the basins to the south of these lakes was prepared

Habitat use and gas bubble disease in southern cavefish (Typhlichthys subterraneus), 1993, Nielsen Carl D. , Noltie Douglas B. , Schubert Alex L. S.
In situ observations of habitat use by southern cavefish (Typhlichthys subterraneus) in a Missouri, U.S.A. spring suggest that groundwater discharge and that zones of substrate which have large interstitial spaces that fish can enter may be important components of the species habitat. Such substrates may also facilitate smallscale dispersal. In addition, we document the first recorded case of gas bubble disease in a laboratory-held specimen of this species. Cavefish may be particularly susceptible to this malady, and the conditions under which it occurred are important to avoid should captive maintenance or propagation of this or related species be attempted.

Estimating subsurface fissure apertures in karst aquifers from equilibrium activities, 1998, Field Ms, Mose Dg,
Rn-222 activities were determined for the karst aquifer underlying Walkersville, Maryland, in an area of ground-water discharge from a single geological unit during the summer and fall seasons, Radon-222 equilibrium activities in karst ground waters can be employed in mass-balance models to estimate microfissure, macrofissure, and conduit aperture dimensions, This approach defines Rn-222 generation and loss in karst aquifers as a function of fissure apertures and the U-238 content of the rock, High Rn-222 activities occur in tight fissures and low Rn-222 activities occur in conduits, In the vadose zone, Rn-222 activities are low as a result of degassing, especially if flow is turbulent and activities are decoupled from the phreatic zone, In the phreatic zone, if recharge to fissures causes a reduction of residence time below that required for equilibrium (approximate to 26 days), Rn-222 activities fall, At springs and in the vadose zone, after a rainfall event, Rn-222 activities increase as waters with long residence and with high Rn-222 activities are expelled from fissure and fracture storage, Field data and selected literature values were used to test the model, Models used to predict median microfissure apertures for this karst aquifer yield aperture estimates ranging from 2.8 mu m to 9.2 mu m. Median macrofissure apertures ranged from 5.53 cm to 5.88 cm, Median conduit apertures ranged from 1.16 m to 1.24 m, Comparison of the models results with published data on karst aquifers and observations at the field site suggest that the predicted apertures are reasonable

River water intrusion to the unconfined Floridan Aquifer, 1998, Kincaid Todd R. ,
Rapid infiltration of river water into unconfined parts of the Floridan aquifer represents a significant component of subsequent ground-water discharge in regions where the aquifer is dissected by surface streams. A two-year investigation of the Devil's Ear cave system, an extensive saturated conduit network in the Floridan aquifer which underlies a 1.5-km reach of the Santa Fe River in north-central Florida, revealed that there is an appreciable and rapid exchange of water between the river and the underlying Floridan aquifer. Natural tracers Radon-222 ( 222 Rn) and delta 18 O were used to quantify these exchanges. Cave diving was employed to collect 50 water samples which were analyzed for tracer content and to observe water clarity conditions within the saturated karst conduits as far as 1.2 km from the cave entrance. 222 Rn concentrations measured in the cave system revealed three distinct zones where river water is rapidly intruded into the Floridan aquifer. A two-component mixing model was used to quantify the intruded river water that was found to account for as much as 62 percent of the discharge at Devil's Ear spring. Observations of diminished water clarity in the cave system following large precipitation events in the highland provinces of the Santa Fe River basin indicate that river water intrusion to the aquifer can occur in as little as one or two days. The results of this investigation imply that, in regions such as the western Santa Fe River basin, there can be no clear distinction between ground and surface waters and intruded river water provides a significant vehicle for contamination of the unconfined Floridan aquifer

Estimating recharge in a tropical karst aquifer, 2000, Jones I. C. , Banner J. L. , Humphrey J. D. ,
Unique constraints on seasonal and spatial variations in recharge to the Pleistocene limestone aquifer of Barbados are obtained from the analysis of oxygen isotopic compositions of groundwater and rainwater. Conventional methods of estimating recharge are based on groundwater chloride variations, coastal groundwater discharge, and potential evapotranspiration. These methods typically yield estimates of recharge for Barbados that range from 9% to 20% of average annual rainfall, with significant uncertainties that arise from poorly constrained model input parameters. Owing to the low relief and tropical climate of Barbados, variations in rainwater and groundwater delta(18)O values are primarily influenced by the amount of rainfall, with negligible temperature or altitude effects. Composite monthly rainwater delta(18)O values are inversely related to rainfall, while groundwater delta(18)O values show little seasonal variability. Rainwater delta(18)O values are equivalent to groundwater values only at the peak of the wet season. By using mass balance, the difference between groundwater and weighted-mean rainwater delta(18)O values gives recharge values. These values are in general agreement with estimates by conventional methods (10-20%) and provide unique additional information including the following: (1) Recharge is restricted to the wettest 1-3 months of the year, and (2) there is less recharge at higher elevations. The effective shift in delta(18)O values between contemporaneous rainwater and groundwater via recharge is a useful tool for estimating temporal and spatial variability in recharge and must be considered in paleoclimatic studies where climate inferences are based on groundwater delta(18)O values preserved in the geologic record

Karst hydrogeology of Kusluk-Dilmetas karst springs, Van-Eastern Turkey, 2001, Ozler H. M. ,
Permian marbles and recrystallised limestone nappes outcrop in the Artos Mountain range and comprise an aquifer with a small storage reservoir. Carbonate units are underlain by the impervious Yuksekova ophiolites. Between the marble and ophiolites, there is a transition zone by the northward thrusting, which varies between 500-1,000 m thickness. Fissures and fractures systems are well-developed in this transition zone because of the effects of tectonic movement, and extensive karstification has resulted in a high infiltration although its storage capacity is low. Because of the impermeable ophiolites at the base, groundwater discharges as springs flowing from the plane of the thrust faults. Numerous karst springs (48 springs) issue from this fissured and fractured zone, which are characterised by small discharge rates, a long residence time, and well-regulated spring flows. In addition, a selective enlargement is observed from west to east, which is greatly effected by strike-slip faults. All these springs are mostly fed by snowmelt during 6 months of the year

Spaceborne imaging radar-C (SIR-C) observations of groundwater discharge and wetlands associated with the Chicxulub impact crater, northwestern Yucatan Peninsula, Mexico, 2001, Pope Kevin O. , Rejmankova Eliska, Paris Jack F. ,
Analyses of spaceborne imaging radar-C (SIR-C) data and field data from the northwestern Yucatan Peninsula, Mexico, demonstrate that spaceborne multifrequency polarimetric radars are excellent tools for characterizing patterns of wetland flooding. Seasonal flooding can be detected in most types of forest and marsh in the radar backscatter magnitude and phase data of both L and C band. Field observations made in the wet and dry seasons concurrent with the space missions and chemical analyses of floodwaters confirm that flooding is the product of discharge from the Yucatan aquifer, which consists of a fresh-water lens floating on seawater. This discharge controls the distribution of wetlands. Therefore, vegetation and flooding patterns, mapped with SIR-C imagery, provide valuable information on the hydrogeology of the region. Radar-image maps of wetlands and flooding indicate that there are three major zones of groundwater discharge that correlate with structures of the buried Chicxulub crater--zone 1 with the peak ring, zone 2 with the crater rim, and zone 3 with the exterior ring. Zone 1 has sulfate-poor discharge, unlike the sulfate-rich discharge in zones 2 and 3. The highest discharge is in zone 3, where the buried crater is closest to the surface. This groundwater-discharge pattern can be explained by tidal pumping of fresh water to the surface through high permeability zones developed in the Tertiary carbonates overlying crater faults and escarpments

Geostatistical and geochemical analysis of surface water leakage into groundwater on a regional scale: a case study in the Liulin karst system, northwestern China, 2001, Wang Y. , Ma T. , Luo Z. ,
The Liulin karst system is typical of hydrogeological systems in northern China, with a group of springs as the dominant way of regional groundwater discharge. Surface water leakage into groundwater has been observed in six sections of the rivers in the study area. To extract hydrogeological information from hydrochemical data, 29 water samples were collected from the system. On a trilinear diagram, most of the groundwater samples are clustered around the surface waters, indicating the effect of leakage on their chemistry. R-mode factor analysis was made on seven variables (Na, Ca, Mg, SO4, Cl, HCO3, and NO3) of the samples and three principal factors were obtained: the F-1 factor is composed of Ca, Mg and SO4, the F-2 of HCO3 and NO3, and the F-3 of Na and Cl. These factors are then used as regionalized variables in ordinary Kriging for unbiased estimates of the spatial variations of their scores. Considering regional hydrogeological conditions, the hydrogeological implications of the spatial distribution of the factor scores as related to the effects of the surface leakage are discussed. To evaluate the geochemical processes, the geochemical modeling code NETPATH was employed. The modeling results: show that mixing commonly occurs in the system and dolomite dissolution is more important than calcite dissolution. Dedolomitization (calcite precipitation and dolomite dissolution driven by anhydrite dissolution) is locally important, in the western flank of the system where the surface water leakage has the least effect.

Toward a coastal ground-water typology, 2001, Bokuniewicz H,
Although submarine ground-water discharge is recognised as being of physical and ecological significance, direct measurements are rare, and calculations are hampered by a lack of offshore data. Classification of the world's coast with respect to its potential, submarine ground-water contribution would help to focus attention on the most important areas and to extrapolate existing data. A classification may be based on relevant physical/climatological parameters (e.g. precipitation, soil type etc.), or geologic/geomorphic classes (e.g. karst, coastal plain, etc.), or on a collection of state parameters. State parameters for a coastal ground-water typology may include aquifer thickness, onshore hydraulic gradient, anisotropy and fractal dimension of the shoreline. Topographic gradient can serve as a surrogate for the hydraulic gradient. A fourth type of classification may be based on the distribution of salinity in the subterranean estuary but adequate subsurface data are not yet available. (C) 2001 Elsevier Science B.V. All rights reserved

Karst groundwater basin delineation, Fort Knox, Kentucky, 2002, Connair Dp, Murray Bs,
Evaluation of karst groundwater quality concern at Fort Knox Kentucky has required the development of a sitewide karst groundwater flow model and basin delineation investigation. The karst aquifer underlying Fort Knox is developed within approximately 60 m of the St. Louis Limestone and is bounded on three sides by surface streams that represent the local base level. The underlying Salem Limestone acts as a regional aquitard and provides a lower limit to karst aquifer development. The study area covers over 130 km(2) and contains over 200-inventoried karst features. As a part of this investigation, innovative multiple dye trace events were conducted throughout the study area using up to six dyes per event with a total of eight dyes used to conduct 14 dye traces during three seasonal events. Dye trace results, structural and topographic controls, spring characteristics, and normalized base flow were used to establish groundwater basin limits and boundary zones and to develop a conceptual sitewide groundwater flow model. The primary finding of this work indicates sitewide groundwater flow is controlled directly or indirectly by local stratigraphy, geologic structure, and changes in stream levels in the geologic past, and that two groundwater basins dominate the study area, accounting for approximately 80% of measured sitewide groundwater discharge. The findings of this investigation will be used to assess the groundwater contaminant contribution from source areas in individual basins, develop an effective groundwater monitoring program, and guide future groundwater management strategies. (C) 2002 Published by Elsevier Science B.V

The hydrogeochemistry of the karst aquifer system of the northern Yucatan Peninsula, Mexico, 2002, Perry E. , Velazquezoliman G. , Marin L. ,
Based on groundwater geochemistry, stratigraphy, and surficial and tectonic characteristics, the northern Yucatan Peninsula, Mexico, a possible analog for ancient carbonate platforms, is divided into six hydrogeochemical/physiographic regions: (1) Chicxulub Sedimentary Basin, a Tertiary basin within the Chicxulub impact crater; (2) Cenote Ring, a semicircular region of sinkholes; (3) Pockmarked Terrain, a region of mature karst; (4) Ticul fault zone; (5) Holbox Fracture Zone-Xel-Ha Zone; and (6) Evaporite Region. Regional characteristics result from tectonics, rock type, and patterns of sedimentation, erosion, and rainfall. The Cenote Ring, characterized by high groundwater flow, outlines the Chicxulub Basin. Most groundwater approaches saturation in calcite and dolomite but is undersaturated in gypsum. Important groundwater parameters are: SO4/Cl ratios related to seawater mixing and sulfate dissolution; Sr correlation with SO4, and saturation of Lake Chichancanab water with celestite. indicating celestite as a major source of Sr; high Sr in deep water of cenotes, indicating deep circulation and contact of groundwater with evaporite; and correlation of Ca, Mg, and SO4, probably related to gypsum dissolution and dedolomitization. Based on geochemistry we propose: (1) a fault between Lake Chichancanab and Cenote Azul; (2) deep seaward movement of groundwater near Cenote Azul; and (3) contribution of evaporite dissolution to karst development in the Pockmarked Terrain. Chemical erosion by mixing-zone dissolution is important in formation of Estuario Celestun and other estuaries, but is perhaps inhibited at Lake Bacalar where groundwater dissolves gypsum, is high in Ca, low in CO3, and does not become undersaturated in calcite when mixed with seawater

Development of collapse sinkholes in areas of groundwater discharge, 2002, Salvati R. , Sasowsky I. D. ,
Collapse sinkholes are found in groundwater recharge zones throughout the world. They cause substantial loss of property each year, and occasional fatalities. In such settings, the formation of these features occurs through the downward migration of regolith into karst voids. The presence of a void in the bedrock. and sufficient seepage pressure or gravitative force in the regolith, is required for their creation. We investigated the development of cover collapse sinkholes in an unusual setting, areas of groundwater discharge rather than recharge. Upward hydraulic gradients and the likelihood of groundwater saturated with respect to calcite are difficult to reconcile with standard models for collapse development. Short flowpaths or renewed groundwater aggressivity towards calcite (via mischungskorrosion, thermally driven circulation, or deep-seated gaseous sources) are hypothetical mechanisms that could generate the subsurface voids that are needed to allow cover collapse development in discharge areas. For the two field sites in central Italy that we investigated, calculated carbon dioxide partial pressures in springs ranged from 7.38 X 10(-2) to 7.29 X 10(-1) atm. This indicates that deep-seated gaseous sources are most likely the mechanism allowing the development of the sinkholes. Groundwater is recharged in surrounding limestone massifs. The water moves through the carbonates and becomes saturated with calcite. As it circulates deeply in to the adjacent valleys, it mixes with deep-seated waters and gaseous fluxes from major fault systems, acquiring renewed aggressivity towards calcite. Finally, the water ascends into confined aquifers in the valley fill, and dissolves carbonate material present within, leading to surface collapse. (C) 2002 Elsevier Science B.V. All rights reserved

Coastal and submarine karstic discharges in theGokova Bay, SW Turkey, 2002, Bayari Cs, Kurttas T,
Hydrochemical, stable isotopic (18O and 2H) and thermal infrared data of LANDSAT 5 TM for sea surface temperature anomalies have been used to determine the extent and spatial variation of salinization in coastal and submarine karstic groundwater discharges in the Gokova Bay area, located in the SW Turkey. The bay is an active graben extending in an east-west direction. An artesian aquifer in the eastern tidal plain is the only source of fresh groundwater, whereas Tertiary and Mesozoic carbonates contacting with sea along the northern coastline provide abundant but saline water. Physical properties, major ion chemistry and stable isotope composition indicate a westward increase in the salinity of the karstic springs. The temporal variation of salinity in groundwater is either related to variations in sea level or in seasonal recharge rates, while some springs have time-invariant salinity. Submarine groundwater discharges were determined successfully from satellite images and verified by ground measurements of pH, temperature and electrical conductivity. Some of these discharges are also characterized by the existence of a halocline, as observed during Scuba diving. The westward-increasing salinity appears to be related to decreasing groundwater discharge in this direction

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