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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 permeameter is a device used to measure the permeability of small samples [16].?

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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 pathway (Keyword) returned 95 results for the whole karstbase:
Showing 1 to 15 of 95
Spatial variability in cave drip water hydrochemistry: Implications for stalagmite paleoclimate records, , Baldini Jul, Mcdermott F, Fairchild Ij,
The identification of vadose zone hydrological pathways that most accurately transmit climate signals through karst aquifers to stalagmites is critical for accurately interpreting climate proxies contained within individual stalagmites. A three-year cave drip hydrochemical study across a spectrum of drip types in Crag Cave, SW Ireland, reveals substantial variability in drip hydrochemical behaviour. Stalagmites fed by very slow drips ( 2[no-break space]ml/min) sites, apparently unconnected with local meteorological events. Water from these drips was typically undersaturated with respect to calcite, and thus did not result in calcite deposition. Data presented here suggest that drips in this flow regime also experience flow re-routing and blocking, and that any stalagmites developed under such drips are unsuitable as mid- to high-resolution paleoclimate proxies. Most drip sites demonstrated seasonal [Ca2] and [Mg2] variability that was probably linked to water excess. Prior calcite precipitation along the flowpath affected the chemistry of slowly dripping sites, while dilution predominantly controlled the water chemistry of the more rapidly dripping sites. This research underscores the importance of understanding drip hydrology prior to selecting stalagmites for paleoclimate analysis and before interpreting any subsequent proxy data

Predicting travel times and transport characterization in karst conduits by analyzing tracer-breakthrough curves, , Morales Tomas, De Valderrama Inigo, Uriarte Jesus A. , Antiguedad Inaki, Olazar Martin,
SummaryThis paper analyzes data obtained in 26 tracer tests carried out in 11 karstic connections following solutional conduits in karst aquifers in the Basque Country. These conduits are preferential drainage pathways in these aquifers and so they confer a marked anisotropy and high vulnerability to them. Consequently, their consideration in protection and management studies and projects is a priority.The connections studied cover a wide hydrogeological spectrum (a wide range of sizes, slopes, geomorphic and hydrologic types) and the tests have been carried out at different hydrodynamic states. It is noteworthy that they all follow a similar trend, which has allowed for the development of a statistical approximation for the treatment of the whole information.Relationships have been established involving velocity, solute time of arrival, attenuation of peak concentration and time of passage of tracer cloud. These relationships are a valuable tool for management and supporting decision-making and allow for making estimates in connections in which the information available was scarce. This information is especially useful, given that the complexity of transport in karst conduits gives way to important deviations between real data (empirical observations) and the data obtained by simple approaches based on the Fickian-type diffusion equation

Le peuplement animal des karsts de France (lments de biogographie souterraine pour les invertbrs, premire partie : la faune aquatique), 1987, Ginet R. , Juberthie C.
THE BIOGEOGRAPHICAL DISTRIBUTION OF INVERTEBRATE ANIMALS IN FRENCH KARSTS (FIRST PART: THE AQUATIC FAUNA) - This text analyses the bibliographic data in order to draw up a schematic representation of the biogeographical distribution of Invertebrate animals found in French karsts up to 1985. The animal population of these karsts is very varied, especially in the South of France. For many groups, there are obvious links with geological history and paleo-ecology. This text first lists the aquatic groups (from Porifera to Crustacea; the latter is the most varied and numerous in karstic water). It puts forward possible solutions to the problems posed by the ways followed by the ancestors of present-day groups, either of superficial fresh-water origin, or of marine origin during the Tertiary, and whose areas were later modified by the impact of Quaternary glaciations. For the terrestrial groups (cf. Karstologia n 11), subterranean penetration followed different pathways, among which the Superficial Hypogean Compartment (MSS = Milieu Souterrain Superficiel) plays an obvious role; this shows that many troglobites are not limited, in the underground environment, to just caves and the karst. The Arthropods, and among them the Insects, are of course the most varied and the best known. Their biogeographical distribution reflects the problems of speciation, ecology and endemism, which are discussed in the text.

Le peuplement animal des karsts de France (deuxime partie : lments de biogographie pour les Invertbrs terrestres), 1988, Ginet R. , Juberthie C.
THE BIOGEOGRAPHICAL DISTRIBUTION OF INVERTEBRATE ANIMALS IN FRENCH KARSTS. SECOND PART THE TERRESTRIAL FAUNA - This text analyses the bibliographic data in order to draw up a schematic representation of the biogeographical distribution of Invertebrate animals found in french karsts up to 1985. The animal population of these karsts is very varied, especially in the south of France. For many groups, there are obvious links with geological history and paleo-ecology. This text first (cf. Karstologia n 10) lists the aquatic groups (from Porifera to Crustacea; the latter is the most varied and numerous in karstic water). It puts forward possible solutions to the problems posed by the ways followed by the ancestors of present-day groups, either of superficial freshwater origin, or of marine origin during the Tertiary, and whose areas were later modified by the impact of quaternary glaciations. This second part concerns the terrestrial groups, subterranean penetration followed different pathways, among which the Superficial Hypogean Compartment (MSS = Milieu Souterrain Superficiel) plays an obvious role; this shows that many troglobites are not limited in the underground environment, just to caves and karst. The Arthropods, and among them the Insects, are of course the most varied and the best known. Their bio-geographical distribution reflects the problems of speciation, ecology and endemism, which are discussed in the text.

Modeling of regional groundwater flow in fractured rock aquifers, PhD Thesis, 1990, Kraemer, S. R.

The regional movement of shallow groundwater in the fractured rock aquifer is examined through a conceptual-deterministic modeling approach. The computer program FRACNET represents the fracture zones as straight laminar flow conductors in connection to regional constant head boundaries within an impermeable rock matrix. Regional scale fracture zones are projected onto the horizontal plane, invoking the Dupuit-Forchheimer assumption for flow. The steady state flow solution for the two dimensional case is achieved by requiring nodal flow balances using a Gauss-Seidel iteration. Computer experiments based on statistically generated fracture networks demonstrate the emergence of preferred flow paths due to connectivity of fractures to sources or sinks of water, even in networks of uniformly distributed fractures of constant length and aperture. The implication is that discrete flow, often associated with the local scale, may maintain itself even at a regional scale. The distribution of uniform areal recharge is computed using the Analytic Element Method, and then coupled to the network flow solver to complete the regional water balance. The areal recharge weakens the development of preferential flow pathways. The possible replacement of a discrete fracture network by an equivalent porous medium is also investigated. A Mohr's circle analysis is presented to characterize the tensor relationship between the discharge vector and the piezometric gradient vector, even at scales below the representative elementary volume (REV). A consistent permeability tensor is sought in order to establish the REV scale and justify replacement of the discrete fracture network by an equivalent porous medium. Finally, hydrological factors influencing the chemical dissolution and initiation of conduits in carbonate (karst) terrain are examined. Based on hydrological considerations, and given the appropriate geochemical and hydrogeological conditions, the preferred flow paths are expected to develop with time into caves.


Elevated and variable values of 13C in speleothems in a British cave system, 1997, Baker A, Ito E, Smart Pl, Mcewan Rf,
[delta] 13C isotope variations in speleothems have been investigated for samples from the British Isles, where plants which use the Hatch-Slack or C4 photosynthetic pathway are not present. The range of [delta] 13C expected in speleothem carbonate formed in isotopic equilibrium with soil CO2 derived from the overlying C3 vegetation should thus fall in the range -12 to -6[per mille sign]. Forty-one actively growing speleothem samples from low-discharge sites were analysed from Stump Cross Caverns, Yorkshire, England. Ten percent have [delta] 13C greater than -6%. In addition, a large range of [delta] 13C was observed (-8.06 1.38[per mille sign], a 1 [sigma] variability of 17%), with adjacent samples having [delta] 13C differing by a maximum of 4.74[per mille sign]. Similar findings were obtained from a review of analyses of late Quaternary speleothem samples from the British Isles, with 75% of flowstone samples and 57% of high-flow stalagmite samples exhibiting elevated [delta] 13C. Three possible processes are proposed as possible causes of elevated [delta] 13C in speleothems. Firstly, fractionation may occur between the stalactite and stalagmite due to evaporation or degassing. Secondly, degassing of the groundwaters may have occurred within the aquifer before reaching the cave void, allowing release of some CO2 from the water whilst remaining saturated in calcium. Finally, the elevated [delta] 13C may be due to short water residence times in the soil, such that equilibrium between soil water and soil CO2 is not reached. Evidence presented here demonstrates that any one of these mechanisms may be important in the karst areas of the British Isles. Caution is needed before interpreting the [delta] 13C signal within speleothems in terms of palaeovegetation

Sinkholes, soils, fractures, and drainage: Interstate 70 near Frederick, Maryland, 1997, Boyer Bw,
Numerous sinkholes have recently formed on both sides of Interstate 70 south of Frederick, Maryland, All the sinkholes are cover-collapse types, which form when soil cavities grow upward from the bedrock surface until their roofs become unstable, Areas at greatest risk for sinkhole development lie within a network of dry swales, The roughly dendritic map pattern and presence of allochthonous siliciclastic alluvium suggest that these swales are the vestiges of a vanished surface drainage system. Sinkholes occur mainly along bedrock escarpments underlying the swales, which are located along an easterly-trending transverse fracture and a series of strike-parallel fractures which intersect with it. Although the surface drainage appears to have Bowed east and north in the past, surface runoff in large quantities is infiltrating the ground or directly entering some of the sinkholes, then following subsurface conduits which convey it southward under the highway. Compaction grouting has been employed to prevent collapse or further subsidence of the most threatened portions of the highway. Soil Survey maps can be useful in locating cryptic intermittent or relict drainage pathways which may be at high risk for sinkhole formation when subjected to anthropogenic concentrations of perched storm water

Geologic controls on porosity development in the Maynardville limestone, Oak Ridge, Tennessee, 1997, Goldstrand P. M. , Shevenell L. A. ,
Understanding the geologic controls of porosity development and their relationship to the karst aquifer system in the Cambrian Maynardville Limestone is important in determining possible contaminant transport pathways and provides essential data for hydrologic models within the Oak Ridge Reservation of east Tennessee. In the Maynardville Limestone, several important factors control porosity development: (1) lithologic controls on secondary microporosity and mesoporosity are related to dissolution of evaporite minerals and dedolomitization in supratidal facies; (2) depth below the ground surface controls the formation of karst features because the most active portion of the groundwater system is at shallow depths, and karst features are rare below approximate to 35 m; and (3) structural controls are related to solution enlargement of fractures and faults

Study on the contamination of fracture-karst water in Boshan District, China, 1997, Zhu X. Y. , Xu S. H. , Zhu J. J. , Zhou N. Q. , Wu C. Y. ,
Boshan is an industrial city in the center of Shandong Province where ground water is the only source for the urban water supply. The major water resource is fracture-karst water in the middle Ordovician carbonate rocks. Based on the hydrogeological investigation and mapping in this area we studied the geologic and hydrogeologic settings, the major pollution sources and the pathways of contamination, the principal contaminants, and their spatial distribution in ground water. The ground-water quality has also been estimated by the fuzzy mathematic method. The geostatistical method, such as the kriging method, was taken to simulate spatial distribution of the contaminants. The grey system method was adopted to forecast future contamination. An attempt at the remediation of Cr6 contamination in fracture-karst water was also discussed. Finally, some proposals for the protection of the ground-water environment in Boshan District are offered

Early evolution of karst aquifers in limestone: Models on two-dimensional percolation clusters, 1997, Dreybrodt W. , Siemers J.
Two-dimensional nets of initial fractures are constructed on a square-lattice by occupying the lines between nearest neighbour sites by a water leading fissure of width a"SUBo" and length l with an occupation probability p. For p > 0.5 percolating nets occur which lead water. To simulate cave genesis we calculate the water flow rates driven by the hydraulic head h through all fissures. By employing nonlinear dissolution rates of the type F=k"SUBn"(l-c/c"SUBeq")'"SUPn" the widening of the fractures is obtained. At the onset of karstification flow is evenly distributed on all fractures. As the system develops solutional widing creates preferred pathways, which attract more and more flow, until at breakthrough both widening and flow increase dramatically. We discuss the evolution of karst aquifers for natural conditions and also upon human impact at dam sites where steep hydraulic gradients may generate water leading conduits below the dam in times comparable to the lifetime of the structure.

An investigation, using the chalk karst of Haute-Normandie (France), as an example of the relationships between the surface and endokarst using a granulometric method, 1998, Lacroix M. , Leboulanger T. , Wang H. Q. , Feeny V. , Dupont J. P. , Meyer R. ,
Karst, by definition, is the result of rock dissolution. Ii the rock is not completely soluble, residues will remain ('acquired' particles). This insoluble material, present in the springs issuing From the karst body after some time lag, provides information regarding karst processes taking place within the rock body. The presence of pathways between the surface and the endokarst is reflected by an increase in the suspended particulate material (SPM) that may be considered to be 'inherited' from outside of the karst system, By the study of microgranulometric spectra the origins of the particles are differentiated and, on this basis, a classification of karst systems is proposed. The technique was applied to the chalk karat of Haute Normandie (France) by obtaining characterisations of the microgranulometric fraction of the main surface formations (clay-with-flints and loess) and that produced by dissolution of the chalk. By the comparison of these spectra with those of the SPM contained in ten karst springs, it was possible to define two types of karsts ('open' and 'closed') and their intermediates. In 'closed' karst a majority of the particles originated from the dissolution of the chalk itself, while in the 'open' karst, the majority of the particles are derived from the surface formations. This notion of 'aperture' is quite different from the conventional allogenic/authigenic karst classification which implies the formation of an impermeable residual soil that focuses surface water inputs

Mise en evidence des relations surface-endokarst par la microgranulometrie, exemple du karst crayeux haut-normand, 1998, Lacroix Michel, Leboulanger Thierry, Wang Huaqing, Feeny Veronique, Dupont Jean Paul, Meyer Robert,
Karst, by definition, is the result of rock dissolution. If the rock is not completely soluble, residues will remain ('acquired' particles). This insoluble material, present in the springs issuing from the karst body after some time lag, provides information regarding karst processes taking place within the rock body. The presence of pathways between the surface and the endokarst is reflected by an increase in the suspended particulate material (SPM) that may be considered to be 'inherited' from outside of the karst system. By the study of microgranulometric spectra the origins of the particles are differentiated and, on this basis, a classification of karst systems is proposed. The technique was applied to the chalk karst of Haute Normandie (France) by obtaining characterisations of the microgranulometric fraction of the main surface formations (clay-with-flints and loess) and that produced by dissolution of the chalk. By the comparison of these spectra with those of the SPM contained in ten karst springs, it was possible to define two types of karsts ('open' and 'closed') and their intermediates. In 'closed' karst a majority of the particles originated from the dissolution of the chalk itself, while in the 'open' karst, the majority of the particles are derived from the surface formations. This notion of 'aperture' is quite different from the conventional allogenic/authigenic karst classification which implies the formation of an impermeable residual soil that focuses surface water inputs

Processes controlling colloid composition in a fractured and karstic aquifer in eastern Tennessee, USA, 1998, Mccarthy J. F. , Shevenell L. ,
Groundwater was sampled from a number of wells along recharge pathways between fractured shale and karstic formations to evaluate the chemical and hydrologic mechanisms controlling the nature and abundance of groundwater colloids. The colloids recovered using low flow rate purging and sampling exhibited a composition and abundance consistent with lithology, flow paths, and effects of hydrology and aqueous chemistry on colloid mobilization and stability. In general, the larger-size colloids and Ca-containing colloids were more abundant in the karstic lithologies, while Na-containing colloids were more important in the shales. The composition of the colloids reflected recharge pathways from the fractured shale and dolomite formations on the ridges into the limestone in the valley floor. The Mg-colloids in the limestone reflect the possible contributions from the dolomite, while the Na, K, and Si reflect possible contributions from the shale, However, it was not possible to use the colloid composition as a signature to demonstrate colloid transport from one lithology to another. Mixing of recharge water from the shale with groundwater within the limestone formation and precipitation/dissolution reactions could account for the colloids present in the limestone without invoking transport of specific shale-derived colloids into the limestone formation. The abundance of colloids in groundwater appears to be controlled by both chemical factors affecting colloid stability, as well as physical factors related to hydrology (storm-driven recharge and water velocities). In general, colloids were more abundant in wells with low ionic strength, such as shallow wells in water table aquifers near sources of recharge at the top of the ridges, Increases in cation concentrations due to dissolution reactions along Bow paths were associated with decreases in colloid abundance. However, in spite of elevated ionic strength, colloid concentrations tended to be unexpectedly high in karstic wells that were completed in cavities or water-bearing fractures. The higher levels of colloids appear to be related to storm-driven changes in chemistry or flow rates that causes resuspension of colloids settled within cavities and fractures. Published by Elsevier Science B.V

Influence of Pedo-chemical Field on Epi-karstification in Subtropical Humid Region-Field Monitoring and Laboratory Experiment , 1998, Pan Genxing, Tao Yuxiang, Teng Yogzhong, Xu Shenyou, Sun Yuhua, Han Fushun

The influence of pedo-chemical conditions on epi-karstification in a karst hydrogeochemical experiment site near Guilin was studied. The dissolution of limestone, and pH, CO2, HCO3- in soil and karst water under soil cover conditions was monitored by using filter tubes containing reference rock plate, and by using portable pH meter, CO2 gas meter and Aqumerck Kit. Laboratory experiments of dissolution under different soil conditions were also conducted by using leaching cylinders. In addition, 13C tracing was carried out on the samples of plant- litter- SOM-soil CO2-spring water-travertine-rock in the karst system. Soil pH, SOM status (subsequently CO2 concentration) and Ca+2 saturation constitutes a pedo-chemical field vigorously affecting the rock dissolution. The carbon in the form of HCO3- in the spring water and of CaCO3 in the travertine was closely related with the soil CO2 gas. Thus, soil carbon through the transferring pathway of air CO2-plant carbon-SOC-soil CO2 was involved in the epi-karstification process, and interface exchange of soil Ca+2, HCO3- with karst water existed in the karst hydrogeochemical flow. A modified model for epi-karstification in the studied area was suggested.


Karstic permeability: organized flow pathways created by circulation, 1999, Huntoon P. W.
Most karstic permeability in soluble rocks is created by the circulation of a solvent through the rockGiven a bit of geologic time, karstic permeability develops a hierarchal structure of highly organized conduits that facilitates the movement of the fluid in the downgradient directionConsequently, karst permeability is not an independent, inherited static attribute of the rock; rather it adjusts dynamically to changing boundary conditions in the flow systemKarstic permeability tends to be the most anisotropic of all the permeability types found in natureThe permeabilities of the dissolution channels generally overwhelm the transmissive characteristics of all the other types of permeability presentConsequently, when dealing with assessments of the impacts of withdrawals or the migration of contaminants in carbonate aquifers, the professional is obligated to find and unravel the character of the organized conduit network; otherwise the essence of the transmissive and storage properties of the flow regime is inadequately formulated, so predictive failures are inevitable

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