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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. ...

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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 anisotropy (Keyword) returned 22 results for the whole karstbase:
Showing 1 to 15 of 22
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

Hydrogeological investigations in northwestern Yucatan, Mexico, using resistivity surveys, 1996, Steinich B. , Marin L. E. ,
Eight Schlumberger soundings and four Wenner anisotropy measurements were conducted in the northwestern section of the Yucatan Peninsula for hydrogeological investigations of a karst aquifer. This system is influenced by a circular high permeability zone (Ring of Cenotes) probably related to the Chicxulub Impact Crater. Schlumberger soundings and Wenner anisotropy measurements show that the karst aquifer can be modeled as an electrically anisotropic medium. Anisotropy is related to preferential permeability directions channeling ground-water flow within the aquifer. Directions of maximum permeability were determined using Wenner anisotropy measurements. Electrical soundings were conducted at different sites near the Ring of Cenotes. Resistivity values decrease toward the Ring of Cenotes supporting the hypothesis that selected segments of the Ring have high permeability. Several soundings were conducted in order to study lateral permeability variations along the Ring. A high permeability section can be identified by low resistivity models and is related to a zone of high cenote density. A low permeability section of the Ring was found showing high resistivity models. This zone overlaps with an area of low cenote density. Electrical soundings were used to determine the depth of the fresh-water lens; the interface was detected along two profiles perpendicular and parallel to the Ring of Cenotes resulting in a depth that ranged from 18 m near the coast up to 110 m in the southeastern part of the study area. The predicted depths of the interface using electrical methods showed a good correlation with Ghyben-Herzberg and measured interface depths at some sites. Discrepancies between calculated and interpreted interface depths at two sites may be explained by horizontal-to-vertical permeability anisotropy

Least-squares fit of an ellipse to anisotropic polar data: Application to azimuthal resistivity surveys in karst regions, 1997, Hart D. , Rudman A. J. ,
Polar plots of various types of anisotropic data are often approximated by ellipses and used by earth scientists as part of the interpretation process. FITELLIPSE, a code to calculate the orientation and values of the major and minor axes of a best-fit ellipse to anisotropic data, is written using Maple, a standard commercial software. A nonlinear statistical parameter is calculated to evaluate the goodness-of-fit. Application to azimuthal resistivity in karst of Indiana demonstrates the direction and degree of the anisotropy. (C) 1997 Elsevier Science Ltd

Anisotropy in carbonate aquifers,, 1999, Palmer A. N

Structural effects on carbonate aquifers, 1999, Sasowsky I. D
Structural geology affects the behavior of karst aquifers by controlling the overall placement and orientation of the limestone and through fracturesThe placement and orientation affect the position of recharge and discharge boundaries to the system, while the fractures serve as pathways for water movementWhen creating a conceptual or numerical model of a karst site, it is useful and cost-efficient to consider all of these effects, as well as the geologic and geomorphic history of the areaBy understanding structural controls on the genesis of the aquifer, predictions can be made regarding current-day behavior in terms of heterogeneity and anisotropy of flowBecause conduits and fissures mainly form along structurally created discontinuities, structural data can be very useful for understanding aquifer behavior, and determining specific high-conductivity flowpaths

The influence of tectonic structures on karst flow patterns in karstified limestones and aquitards in the Jura Mountains, Switzerland, 2000, Herold T. , Jordan P. , Zwahlen F. ,
The development of karst systems is often assumed to be related to tectonic structures, i. e. joints and faults. However, detailed studies report many of these structures to be indifferent ui even obstacles to karst development. The aim of our study is to present a systematic which helps to explain or even predict whether a specific fault or joint, or a class of such structures are permeable (and therefore likely to be widened to karat conduits) or impermeable. Therefore three extended multi-tracer experiments followed by three months of monitoring were performed at some 95 springs and streams in the Eastern Jura fold-and-thrust belt. In addition, detailed mapping of tectonic and hydrogeological structures, including sinkholes and some 600 springs, has been carried out. The study area is characterised by two large anticlines, which have been affected by pre-fold normal faulting and synorogenic folding and thrusting as well as oblique reactivation of pre-existing faults. Hydrogeologically, two karst aquifers can be distinguished, the lower Mid Jurassic Hauptrogenstein (Dogger Limestone) and the upper Late Jurassic Malm Limestone. Both karst aquifers are confined and separated From each other hy impermeable layers. This study has shown that karst development and groundwater circulation is strongly controlled by tectonic structures resulting in specific meso- to macro-scale anisotropies. Fast long distance transport along fold axes in crest and limb at cas of anticlines is found to be related to extension joints resulting from synorogenic folds. Concentrated lateral drainage of water now from anticline limbs is exclusively related to pre-orogenic normal faults, which have been transtensively reactivated during folding. The same structures are also responsible for the significant groundwater exchange between the lower (inner) and upper (outer) aquifer. This water now, through otherwise impermeable layers, which is reported at several places and in both directions, is suspected to take place in porous calcite fault gouges or fault breccias. Transpressively reactivated normal faults and synorogenic reverse faults, on the other band. are found to have no influence on karst development and groundwater circulation. It is proposed that the systematic found in the Weissenstein area, i.e. that karst conduit development is mainly controlled by extensive or transtensive (reactivated) joints and faults, may also be applied to other tectonically influenced karat regions. Transpressive structures have no significant influence on karst system development and may even act as obstacles

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

Evaluation of aquifer thickness by analysing recession hydrographs. Application to the Oman ophiolite hard-rock aquifer, 2003, Dewandel B, Lachassagne P, Bakalowicz M, Weng P, Almalki A,
For more than a century, hydrologists and hydrogeologists have been investigating the processes of stream and spring baseflow recession, for obtaining data on aquifer characteristics. The Maillet Formula [Librairie Sci., A. Hermann, Paris (1905) 218], an exponential equation widely used for recession curve analysis, is an approximate analytical solution for the diffusion equation in porous media whereas the equation proposed by Boussinesq [C. R. Acad. Sci. 137 (1903) 5; J. Math. Pure Appl. 10 (1904) 5], that depicts baseflow recession as a quadratic form, is an exact analytical solution. Other formulas currently used involve mathematical functions with no basis on groundwater theory. Only the exact analytical solutions can provide quantitative data on aquifer characteristics. The efficiency of the two methods was compared on the basis of recession curves obtained with a 2D cross-sectional finite differences model that simulates natural aquifers. Simulations of shallow aquifers with an impermeable floor at the level of the outlet show that their recession curves have a quadratic form. Thus, the approximate Maillet solution largely overestimates the duration of the 'influenced' stage and underestimates the dynamic volume of the aquifer. Moreover, only the Boussinesq equations enable correct estimates of the aquifer parameters. Numerical simulations of more realistic aquifers, with an impermeable floor much deeper than the outlet, proves the robustness of the Boussinesq formula even under conditions far from the simplifying assumptions that were used to integrate the diffusion equation. The quadratic form of recession is valid regardless of the thickness of the aquifer under the outlet, and provides good estimates of the aquifer's hydrodynamic parameters. Nevertheless, the same numerical simulations show that aquifers with a very deep floor provide an exponential recession. Thus, in that configuration, the Maillet formula also provides a good fit of recession curves, even if parameter estimation remains poor. In fact, the recession curve appears to be closer to exponential when flow has a very important vertical component, and closer to quadratic when horizontal flow is dominant. As a consequence, aquifer permeability anisotropy also changes the recession form. The combined use of the two fitting methods allows one to quantify the thickness of the aquifer under the outlet. (C) 2003 Elsevier Science B.V. All rights reserved

Identification of karst features using seismic P-wave tomography and resistivity anisotropy measurements, 2004, Karaman Abdullah, Lar Turhan,

Structural framework of the Edwards Aquifer recharge zone in south-central Texas, 2004, Ferrill Da, Sims Dw, Waiting Dj, Morris Ap, Franklin Nm, Schultz Al,
The Edwards Aquifer, the major source of water for many communities in central Texas, is threatened by population growth and development over its recharge zone. The location of the recharge and confined zones and the flow paths of the aquifer are controlled by the structure of and deformation processes within the Balcones fault system, a major system of predominantly down-to-the-southeast normal faults. We investigate the geologic structure of the Edwards Aquifer to assess the large-scale aquifer architecture, analyze fault offset and stratigraphic juxtaposition relationships, evaluate fault-zone deformation and dissolution and fault-system architecture, and investigate fault-block deformation and scaling of small-scale (intrablock) normal faults. Characterization of fault displacement shows a pattern of aquifer thinning that is likely to influence fault-block communication and flow paths. Flow-path constriction may be exacerbated by increased fault-segment connectivity associated with large fault displacements. Also, increased fault-zone deformation associated with larger-displacement faults is likely to further influence hydrologic properties. Overall, faulting is expected to produce strong permeability anisotropy such that maximum permeability is subhorizontal and parallel to fault-bedding intersections. At all scales, aquifer permeability is either unchanged or enhanced parallel to faults and in many cases decreased perpendicular to faults

Hydraulic and geological factors influencing conduit flow depth, 2005, Worthington, S. R. H.

There has much been speculation as to whether cave formation should occur at, above, or below the water table, but a satisfactory explanation has been lacking until recently. The last 50 years has seen extensive mapping of caves both above and, more recently, below the water table. It is now becoming apparent that there are systematic differences in depth of flow between different areas and that conduit flow to depths >100m below the water table is not uncommon. Such deep flow is facilitated by the lower viscosity of geothermally heated water at depth. Analysis of data from caves shows that depth of flow is primarily a function of flow path length, stratal dip and fracture anisotropy. This explains why conduits form at shallow depths in platform settings such as in Kentucky, at moderate depths (10–100m) in folded strata such as in England and in the Appalachian Mountains, and at depths of several hundred metres in exceptional settings where there are very long flow paths.

Evidence for hydraulic heterogeneity and anisotropy in the mostly carbonate Prairie du Chien Group, southeastern Minnesota, USA, 2006, 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)

Karst and Early Fracture Networks in Carbonates, Turks and Caicos Islands, British West Indies, 2007, Guidry Sean A. , Grasmueck Mark, Carpenter Daniel G. , Gombos Andrew M. Jr. , Bachtel Steven L. , Viggiano David A. ,
Historically, studies of Quaternary carbonates have not adequately addressed the influence of early fracture networks on diagenesis. Because of this lack of detail, understanding and predicting fracture-related diagenetic heterogeneities and preferential fluid flow pathways in ancient carbonate successions is particularly challenging. The Pleistocene oolitic grainstones of the Caicos platform provide an excellent opportunity to evaluate the relative importance of fractures on early diagenetic alteration styles, and are a suitable analog for subsurface carbonate reservoirs. Detailed analyses of fractures (e.g., orientation, aperture, spacing, fill material) from Caicos outcrops combined with high-resolution, three-dimensional ground-penetrating radar (3D GPR), assisted in exploring the causality and distribution of fractures and relationship to karst. Four models were evaluated to explain the observed distribution of dolines: (1) gravitational, fractured-margin controlled, (2) tectonic-fracture controlled, (3) antecedent-topography controlled, and (4) a hybrid model. Based on observations of numerous fractures (n = 306) on the western Caicos platform, early fractures are abundant and dominantly margin-parallel. These fracture networks are well established in limestones prior to mineralogical stabilization, thereby indicating that diagenetic heterogeneities evolve very early in carbonate diagenesis. The spatial distribution of dolines on Providenciales is likely the result of a complex interplay between the antecedent topography, margin-parallel fracture systems, and meteoric fluids. Resultant diagenetic alteration is far more complicated than simple, unconfined, meteoric lenses associated with topographic highs. Any attempts to model early diagenesis in carbonates should not dismiss the role of fractures as diagenetic facilitators and diagenetic anisotropy templates

Alteration of fractures by precipitation and dissolution in gradient reaction environments: Computational results and stochastic analysis, 2008, Chaudhuri A. , Rajaram H. , Viswanathan H.

Precipitation and dissolution reactions within fractures alter apertures, which in turn affects their flow and transport properties. Different aperture alteration patterns occur in different flow and reaction regimes, and they are also influenced by preferential flow resulting from spatial variations in the aperture. We consider the alteration of variable-aperture fractures in gradient reaction regimes, where fluids are in chemical equilibrium with a mineral everywhere but precipitation and dissolution are driven by solubility gradients associated with temperature variations. The temperature field is defined by a geothermal gradient corresponding to a conduction-dominated heat transfer regime. Monte Carlo simulations on computer-generated aperture fields vividly illustrate pattern formation resulting from two-way feedback between fluid flow and reactive alteration. In dissolution-controlled systems, distinct dissolution channels develop along the dominant flow direction, while elongated precipitate bodies form perpendicular to the mean flow direction in precipitation-controlled systems. Aperture variability accelerates the increase and decrease of effective transmissivity by dissolution and precipitation, respectively. The dominance of precipitation versus dissolution is determined by the angle between the mean hydraulic gradient and solubility/temperature gradient. Development of pronounced anisotropy with oriented elongate features is the key feature of aperture alteration in gradient reaction regimes. A stochastic analysis is developed, which consistently predicts general trends in the aperture field during reactive alteration, including the mean, variance, and spatial covariance structure. Our results are relevant to understanding the long-term diagenetic evolution of fractures in conduction-dominated heat transfer regimes and related problems such as emplacement of ocean bed methane hydrates.

Principal features and problems of karst hydrogeology: Speleogenetic approach, 2008, Klimchouk A. B.

The principal problems of karst hydrogeology and its distinctions from “common” hydrogeology are rooted in the facts that porosity and permeability in karst aquifers 1) are characterised by high heterogeneity and anisotropy, 2) are not inherent and static characteristics of an aquifer but form and develop in the process of the dissolution action of flow on the host rocks. Speleogenetic research focuses on deciphering of mechanisms and rates of solution conduits development, in final analysis – on their evolution, i.e. on revealing of nature of extreme heterogeneity and anisotropy of percolation properties and hierarchical organization of permeability.

The paper provides general characterization of karst porosity and permeability and discusses conceptual models of karst aquifers. Karst aquifers have multi-porosity structure, with respective flow components demonstrating different hydrodynamic behaviour and complex interaction. Various methods of determination of percolation properties characterize medium on a certain level, depending on the scale of the tested domain. Conduit permeability can be adequately estimated only in the scale of a basin (karst hydrological system). Validity of hydrogeological modeling decreases from regional to the local scales of a domain. 

Advances in development of speleogenesis theory attained in last decades of the 20 century render large influence on understanding of peculiar features of karst hydrogeology. The paper outlines principal theoretical regularities of speleogenesis, which, as well as respective conduit permeability structures, differ substantially for unconfined and confined hydrogeological environments.

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