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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 guanobia is an animal association feeding on guano. not considered true cavernicoles as guano is not confined to caves.?

Checkout all 2699 terms in the KarstBase Glossary of Karst and Cave Terms

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Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
See all featured articles
Featured articles from other Geoscience Journals
Karst environment, Culver D.C.
Mushroom Speleothems: Stromatolites That Formed in the Absence of Phototrophs, Bontognali, Tomaso R.R.; D’Angeli Ilenia M.; Tisato, Nicola; Vasconcelos, Crisogono; Bernasconi, Stefano M.; Gonzales, Esteban R. G.; De Waele, Jo
Calculating flux to predict future cave radon concentrations, Rowberry, Matt; Marti, Xavi; Frontera, Carlos; Van De Wiel, Marco; Briestensky, Milos
Microbial mediation of complex subterranean mineral structures, Tirato, Nicola; Torriano, Stefano F.F;, Monteux, Sylvain; Sauro, Francesco; De Waele, Jo; Lavagna, Maria Luisa; D’Angeli, Ilenia Maria; Chailloux, Daniel; Renda, Michel; Eglinton, Timothy I.; Bontognali, Tomaso Renzo Rezio
Evidence of a plate-wide tectonic pressure pulse provided by extensometric monitoring in the Balkan Mountains (Bulgaria), Briestensky, Milos; Rowberry, Matt; Stemberk, Josef; Stefanov, Petar; Vozar, Jozef; Sebela, Stanka; Petro, Lubomir; Bella, Pavel; Gaal, Ludovit; Ormukov, Cholponbek;
See all featured articles from other geoscience journals

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Your search for karst aquifers (Keyword) returned 417 results for the whole karstbase:
Showing 406 to 417 of 417
Identification of the Exchange Coefficient from Indirect Data for a Coupled Continuum Pipe-Flow Model, 2014, Wu X. , Kugler Ph. , Lu Sh.

Calibration and identification of the exchange effect between the karst aquifers and the underlying conduit network are important issues in order to gain a better understanding of these hydraulic systems. Based on a coupled continuum pipe-flow (CCPF for short) model describing flows in karst aquifers, this paper is devoted to the identification of an exchange rate function, which models the hydraulic interaction between the fissured volume (matrix) and the conduit, from the Neumann boundary data, i.e., matrix/conduit seepage velocity. The authors formulate this parameter identification problem as a nonlinear operator equation and prove the compactness of the forward mapping. The stable approximate solution is obtained by two classic iterative regularization methods, namely, the Landweber iteration and Levenberg-Marquardt method. Numerical examples on noisefree and noisy data shed light on the appropriateness of the proposed approaches


Deep conduit flow in karst aquifers revisited, 2014, Kaufmann Georg, Gabrovšek Franci, Romanov Douchko

Caves formed in soluble rocks such as limestone, anhydrite, or gypsum are efficient drainage paths for water moving through the aquifer from the surface of the host rock towards a resurgence. The formation of caves is controlled by the physical solution through dissociation of the host rock by water or by the chemical solution through reactions of the host rock with water enriched with carbon dioxide. Caves as large underground voids are simply the end member of secondary porosity and conductivity characterizing the aquifer.

Caves and their relation to a present or past base level are found both close to a past or present water table (water-table caves) and extending far below a past or present water table (bathy-phreatic caves). One explanation for this different speleogenetic evolution is the structural control: Fractures and bedding partings are preferentially enlarged around more prominent faults, thus the fracture density in the host rock controls the speleogenetic evolution. This widely accepted explanation [e.g. Ford and Ewers, 1978] can be extended by adding other controls, e.g. a hydraulic control: As temperature generally increases with depth, density and viscosity of water change, and particularly the reduction of viscosity due to the increase in temperature enhances flow. This hypothesis was proposed by Worthington [2001, 2004] as a major controlling factor for the evolution of deep-bathyphreatic caves.

We compare the efficiency of structural and hydraulic control on the evolution of a cave passage by numerical means, adding a third control, the chemical control to address the change in solubility of the circulating water with depth. Our results show that the increase in flow through deep bathy-phreatic passages due to the decrease in viscosity is by far outweighted by effects such as the decrease in fracture width with depth due to lithostatic stress and the decrease in solubility with depth. Hence, the existence of deep bathy-phreatic cave passages is more likely to be controlled by the structural effect of prominent faults.


Characterisation and modelling of conduit restricted karst aquifers – Example of the Auja spring, Jordan Valley, 2014, Schmidta Sebastian, Geyera Tobias, Guttmanb Joseph, Mareic Amer, Riesd Fabian, Sauter Martin

The conduit system of mature karstified carbonate aquifers is typically characterised by a high hydraulic conductivity and does not impose a major flow constriction on catchment discharge. As a result, discharge at karst springs is usually flashy and displays pronounced peaks following recharge events. In contrast, some karst springs reported in literature display a discharge maximum, attributed to reaching the finite discharge capacity of the conduit system (flow threshold). This phenomenon also often leads to a non-standard recession behaviour, a so called “convex recession”, i.e. an increase in the recession coefficient during flow recession, which in turn might be used as an indicator for conduit restricted aquifers. The main objective of the study is the characterisation and modelling of those hydrogeologically challenging aquifers. The applied approach consists of a combination of hydrometric monitoring, a spring hydrograph recession and event analysis, as well as the setup and calibration of a non-linear reservoir model. It is demonstrated for the Auja spring, the largest freshwater spring in the Lower Jordan Valley. The semi-arid environment with its short but intensive precipitation events and an extended dry season leads to sharp input signals and undisturbed recession periods. The spring displays complex recession behaviour, exhibiting exponential (coefficient α) and linear (coefficient β) recession periods. Numerous different recession coefficients α were observed: ∼0.2 to 0.8 d−1 (presumably main conduit system), 0.004 d−1 (fractured matrix), 0.0009 d−1 (plateau caused by flow threshold being exceeded), plus many intermediate values. The reasons for this observed behaviour are the outflow threshold at 0.47 m3 s−1 and a variable conduit–matrix cross-flow in the aquifer. Despite system complexity, and hence the necessity of incorporating features such as a flow threshold, conduit–matrix cross-flow, and a spatially variable soil/epikarst field capacity, the developed reservoir model is regarded as relatively simplistic. As a number of required parameters were calculated from the hydrogeological analysis of the system, it requires only six calibration parameters and performs well for the highly variable flow conditions observed. Calculated groundwater recharge in this semi-arid environment displays high interannual variability. For example, during the 45-year simulation period, only five wet winter seasons account for 33% of the total cumulative groundwater recharge.


Karst water resources in a changing world: Review of hydrological modeling approaches, 2014,

Karst regions represent 7–12% of the Earth’s continental area, and about one quarter of the global population is completely or partially dependent on drinking water from karst aquifers. Climate simulations project a strong increase in temperature and a decrease of precipitation in many karst regions in the world over the next decades. Despite this potentially bleak future, few studies specifically quantify the impact of climate change on karst water resources. This review provides an introduction to karst, its evolution, and its particular hydrological processes. We explore different conceptual models of karst systems and how they can be translated into numerical models of varying complexity and therefore varying data requirements and depths of process representation. We discuss limitations of current karst models and show that at the present state, we face a challenge in terms of data availability and information content of the available data. We conclude by providing new research directions to develop and evaluate better prediction models to address the most challenging problems of karst water resources management, including opportunities for data collection and for karst model applications at so far unprecedented scales


Hydrogeological and Environmental Investigations in Karst Systems, 2014,

Karst is the result of climatic and geohydrological processes, mainly in carbonate and evaporite rocks, during geological periods of Earth history. Dissolution of these rock formations over time has generated karst aquifers and environments of significant water and mineral resources. In addition, beautiful landscapes have been created which constitute natural parks, geosites, and caves. Due to their origin and nature, karstified areas require investigation with special techniques and methodology. International collaboration and discussions on advances in karst research are necessary to promote Karst Science. The International Symposium on Karst Aquifers is one of the worldwide events held periodically to specifically address karst environments. The symposium constitutes an ongoing international forum for scientific discussion on the progress made in research in karst environments. The first and second symposiums were organized in Nerja (near Malaga, Spain), in 1999 and 2002; the third and fourth symposiums were held in Malaga city in 2006 and 2010. The 5th International Symposium on Karst Aquifers (ISKA5) occurred in Malaga on during October 14–16, 2014. It was organized by the Centre of Hydrogeology University of Málaga (CEHIUMA) and the Spanish Geological Survey (IGME), in cooperation with UNESCO and the International Association of Hydrogeologists (IAH) Karst Commission. More than 100 contributions were received from 30 countries on five continents. Presentations made during the symposium and published in this book are a compendium of 70 of these manuscripts. Papers submitted by April 2014, were peer-reviewed and subsequently accepted by the Scientific Committee. Contributions are grouped into five sections:

• Methods Utilized to Study Karst Aquifers.

• Karst Hydrogeology.

• Mining and Engineering in Karst media.

• Karst Cavities.

• Karst Geomorphology and Landscape.

A large part of the contributions, 30 %, is related to Methods Utilized to Study Karst Aquifers. Several issues are addressed: methods for groundwater recharge assessment, dye tracer and stable isotope applications, analysis of hydrodynamic data and hydrochemistry, among others. Most contributions, 40 %, however, are on Karst Hydrogeology. These are primarily in connection with various topics such as numerical modeling in karst, floods, karst groundwater flow, protection of karst aquifers or pollution, and vulnerability in karst. Five percent of the published papers deal with Mining and Engineering in Karst Media. These papers are about tunnels, hydrogeological risks, and karst risk assessment in mining and civil engineering. Another section concerning Karst Cavities encompasses 15 % of the contributions. These chapters deal with corrosion and speleogenetic processes, speleothems, CO2 sources, the global carbon cycle in endokarst, and the study of past climate. Karst Geomorphology and Landscape constitutes the remaining 10 % of the contributions. These papers are related to karst features, wetlands, hypogene speleogenesis, geodiversity, and karstic geosites. The results of project work performed by karst specialists worldwide are described in the book. Included in it are experiences from pilot sites, methodologies, monitoring, and data analyses in various climatic, geological, and hydrogeological contexts. Material presented may be utilized for activities such as teaching and technical-professional applications particularly as they apply to the increasingly multidisciplinary nature of karst studies. Information provided may also be useful to decisions makers in making critical decisions regarding development in karst regions. Scientists and engineers and many of the lay public interested in karst environments will benefit from the contents


Hydrogeological Characteristics of Carbonate Formations of the Cuddapah Basin, India, 2014, Farooq Ahmad Dar

Karst hydrogeology is an important field of earth sciences as the aquifers in carbonate formations represent vital resource of groundwater that feeds a large part of the world population particularly in semi-arid climates. These unique aquifers posses peculiar characteristics developed by dissolutional activities of water. Karst aquifers possess a typical hydrogeological setup from surface to subsurface. The aquifers are governed by slow groundwater flow in matrix porosity, a medium to fast flow in fractures and rapid flow in conduits and channels. This large variability in their properties makes the prediction and modeling of flow and transport very cumbersome and data demanding. The aquifers are vulnerable to contamination as the pollutants reach the aquifer very fast with little or no attenuation. The geomorphological and hydrogeological properties in these aquifers demand specific techniques for their study. The carbonate aquifers of the semi-arid Cuddapah basin were characterized based on geomorphological, hydrogeological and hydrochemical investigations. All the formations are highly karstified possessing one of the longest and deepest caves of India and few springs along with unique surface features. Karstification is still in progress but at deeper levels indicated by growing speleothems of different architectural size. Model of karstification indicates that lowering of base level of erosion resulted in the dissolution of deeper parts of the limestone as represented by paleo-phreatic conduits in the region. Moist conditions of the past were responsible for the karst development which has been minimized due to the onset of monsoon conditions. Karst has developed at various elevations representing the past base levels in the region.

The recharge processes in these aquifers are complex due to climatic and karst specificities. Point recharge is the major contributor which enters the aquifer as allogenic water. It replenishes the groundwater very rapidly. Diffuse recharge travels through soil and epikarst zone. Average annual recharge of semi-arid Narji limestone aquifer is 29% of the rainfall which occurs during 5-7 rain events in the year.

The hydrogeochemical characteristic of karst aquifers is quite varaible. A significant difference is observed in hydrochemistry. High concentrations of SO42-, Cl-, NO3- suggests the anthropogenic source particularly from agriculture. Local Meteoric Water Line of δ2H and δ18O isotopes of rain and groundwater shows a slope of 7.02. Groundwater isotope data shows more depletion in heavy isotopes -a result of high evaporation of the area. Groundwater samples show a trend with a slope of 4 and 3.1 for δ2H and δ18O respectively. Groundwater during dry months gets more fractionated due to higher temperature and little rainfall. The irrigated water becomes more enriched and then recharges the aquifer as depleted irrigation return flow. The isotopes show large variation in spring water. Few springs are diffuse or mixed type and not purely of conduit type in the area. Tracer results indicate that the tracer output at the sampling location depends on the hydrogeological setup and the nature of karstification.

The study has significantly dealt with in disclosing the typical characteristics of such aquifer systems and bringing out a reliable as well as detailed assessment of various recharges to the system. The groundwater chemistry has been elaborated to establish the nature of possible hydrochemical processes responsible for water chemistry variation in semi-arid karst aquifer. Such study has thrown light on the aquifers that are on one hand very important from social and strategic point of view and on the hand were left unattended from the detailed scientific studies.


Caractérisation et modélisation hydrodynamique des karsts par réseaux de neurones. Application à l’hydrosystème du Lez , 2014, Virgile, Taver

Improving knowledge of karst hydrodynamics represents a global challenge for water resources because karst aquifers provide approximately 25% of the world population in fresh water. Nevertheless, complexity, anisotropy, heterogeneity, non-linearity and possible non-stationarity of these aquifers make them underexploited objects due to the difficulty to characterize their morphology and hydrodynamics. In this context, the systemic paradigm proposes others methods by studying these hydrosystems through input-output (rainfall-runoff) relations.

The approach proposed in this thesis is to use information from field measurement and from systemic analyses to constrain neural network models. The goal is to make these models interpretable in terms of hydrodynamic processes by making model functioning to be similar to natural system in order to obtain a good representation and extract knowledge from model parameters.

This work covers the association of information available on the hydrosystem with correlation and spectral analyses to develop a temporal multiresolution decomposition of variables and to constrain neural network models. A new method for variable selection, adapted to represent long term hydrodynamics of the system, has been proposed. These constrained models show very good results and allow, through their parameters, to study the temporal contribution of inputs variables to the output.

Modeling nonlinear and non-stationary hydrosystems with neural network has been improved by a novel implementation of data assimilation. More precisely, when non-stationarity is attributed to the catchment, data assimilation is used to modify the model parameters. When the inputs are non-stationary, data assimilation can be used to modify the inputs.

The modification of inputs opens considerable scope to: i) fill gaps or homogenizing time series, ii) estimate effective rainfall.

Finally, these various analyses and modeling methods, mainly developed on the karst hydrosystem Lez, can improve the knowledge of the rainfall-runoff relationship at different time scales. These methodological tools thus offer perspectives of better management of the aquifer in terms of floods and resources. The advantage of these analyses and modeling tools is that they can be applicable to other systems.


Thermal damping and retardation in karst conduits, 2015, Luhmann A. J. , Covington M. D. , Myre J. M. , Perne M. , Jones S. W. , Alexander Jr. E. C. , Saar M. O

Water temperature is a non-conservative tracer in the environment. Variations in recharge temperature are damped and retarded as water moves through an aquifer due to heat exchange between water and rock. However,within karst aquifers, seasonal and short-term fluctuations in recharge temperature are often transmitted over long distances before they are fully damped. Using analytical solutions and numerical simulations, we develop relationshipsthat describe the effect of flow path properties, flow-through time, recharge characteristics, and water and rock physical properties on the damping and retardation of thermal peaks/troughs in karst conduits. Using these relationships, one can estimate the thermal retardation and damping that would occur under given conditions with a given conduit geometry. Ultimately, these relationships can be used with thermal damping and retardation field data to estimate parameters such as conduit diameter. We also examine sets of numerical simulations where we relax some of the assumptions used to develop these relationships, testing the effects of variable diameter, variable velocity, open channels, and recharge shape on thermal damping and retardation to provide some constraints on uncertainty. Finally, we discuss a multitracer experiment that provides some field confirmation of our relationships. High temporal resolution water temperature data are required to obtain sufficient constraints on the magnitude and timing of thermal peaks and troughs in order to take full advantage of water temperature as a tracer.

 


Quantitative hermeneutics: Counting forestructures on a path from W. M. Davis to the concept of multiple-permeability karst aquifers., 2015,

Hermeneutics is the theory of interpretation. One of its major components is recognizing prejudgments, or forestructures, that we bring to our objects of study. In this paper, we construct a historical narrative of the evolution of thinking about the role of caves in relation to groundwater flow in limestone, and we tabulate forestructures as they appear in the story. This account consists of three overlapping time periods: the before and after of an incident that repelled hydrogeologists and students of karst from each other in the middle of the 20th century; a period, up to around the turn of this century, when karst science and mainstream hydrogeology were on different tracks; and a period of convergence, now intertwining, beginning roughly in the last quarter of the 20th century. Two influential players in our story are M.K. Hubbert, whose introduction of the Eulerian perspective of flow was a force for divergence, and R.M. Garrels, whose founding of the field of sedimentary geochemistry was a force for convergence. Other key players include F.T. Mackenzie, J.E. Mylroie, V.T. Stringfield, the U.S. Geological Survey, the Bermuda Biological Station, and the Gerace Research Center in the Bahamas, along with the historical accounts of W.B. White. Our narrative ends with the broader acceptance of the concept of multiple-permeability karst aquifers. We flag in our construction a total of 43 forestructures distributed amongst the categories of hermeneutic theory: 14 in the category of preconceptions; 9 in goals; 14 in tools such as skills; and 6 in tools such as institutions. These counts are an example of the concept of social construction of statistics, and we discuss the implications in terms of the huge number of potential combinations of forestructures that could shape alternative historical narratives of this subject over this time frame.


Deep speleological salt contamination in Mediterranean karst aquifers: perspectives for water supply, 2015,

On the Mediterranean coast, submarine karst springs are common. Most of them are brackish and various unsuccessful attempts in France, Greece, and Italy indicate that it is impossible to diminish the salinity at the spring. Based on studies on the shores of south-eastern France and in Kefalonia (Greece), we propose a working model that explains the mechanism of salt contamination. During the Messinian Deep Stage (-5.9 to 5.3 Ma), a substantial sea-level lowering in the Mediterranean allowed the existence of cave networks extending several hundreds of meters below the present sea level. Seawater is now sucked into the system through these caves. This mechanism is supported by a study of the Port Miou underground river (Cassis, France). In the Port Miou cave system, which extends to 250 m below sea level, titanium and heavy metals are present in the sediment. They are similar to those found in the Cassidaigne submarine canyon, which reinforces the hypothesis of a connection between the cave and the canyon. Recent geological studies prove a Messinian origin for the canyon and support the deep contamination model. The model is also supported by examples on Kefalonia Island (Greece) and in the Toix–Moraig system (Spain) where salt-water intrusions are observed in coastal sinkholes and sea caves. This model explains why various attempts to diminish the salinity of these brackish springs, through the construction of dams to increase head, have failed.On the Mediterranean coast, submarine karst
springs are common. Most of them are brackish and various
unsuccessful attempts in France, Greece, and Italy
indicate that it is impossible to diminish the salinity at the
spring. Based on studies on the shores of south-eastern
France and in Kefalonia (Greece), we propose a working
model that explains the mechanism of salt contamination.
During the Messinian Deep Stage (-5.9 to 5.3 Ma), a
substantial sea-level lowering in the Mediterranean
allowed the existence of cave networks extending several
hundreds of meters below the present sea level. Seawater is
now sucked into the system through these caves. This
mechanism is supported by a study of the Port Miou
underground river (Cassis, France). In the Port Miou cave
system, which extends to 250 m below sea level, titanium
and heavy metals are present in the sediment. They are
similar to those found in the Cassidaigne submarine canyon,
which reinforces the hypothesis of a connection
between the cave and the canyon. Recent geological
studies prove a Messinian origin for the canyon and support
the deep contamination model. The model is also
supported by examples on Kefalonia Island (Greece) and in
the Toix–Moraig system (Spain) where salt-water intrusions
are observed in coastal sinkholes and sea caves. This
model explains why various attempts to diminish the
salinity of these brackish springs, through the construction
of dams to increase head, have failed.


Turkish karst aquifers, 2015, Gunay G. , Guner N. , Tork K.

One third of Turkey’s surface is underlain by carbonate rocks that have been subdivided into four karst regions. The carbonate rock units are about 200 km wide along the Taurus Mountains that attain elevations of 2500 m. Karst features of western Turkey bordering the Aegean and Mediterranean seas demonstrate the tectonic, lithological and climatic controls on the occurrence, movement, and chemical characteristics of groundwater. In Turkey all karstic feature, such as lapies, caves, sinkholes, uvalas, poljes, ground river valleys developed in all karstic areas. Karstification is related not only to the thickness and to purity of limestone, climate and height but also to tectonic movements. Water resources of karst terrains of Turkey are relatively rich and as such are very important for the economic development of the country. High mountain chains, very often associated with the karst terrains, are responsible for some important and beneficial characteristics of these water resources. Four karst regions are: (1) Taurus karst region, (2) southeast Anatolia karst region, (3) central Anatolia karst region, and (4) northwest Anatolia and Thrace karst regions.


Chemistry and Karst, 2015, White, William B.

The processes of initiation and development of characteris­tic surface karst landforms and underground caves are nearly all chemical processes. This paper reviews the advances in understanding of karst chemistry over the past 60 years. The equilibrium chemistry of carbonate and sulfate dissolution and deposition is well established with accurate values for the necessary constants. The equations for bulk kinetics are known well enough for accurate modeling of speleogenetic processes but much is being learned about atomic scale mechanisms. The chemistry of karst waters, expressed as parameters such as total dissolved carbonates, saturation index, and equilibrium carbon dioxide pressure are useful tools for probing the internal char­acteristics of karst aquifers. Continuous records of chemical parameters (chemographs) taken from springs and other karst waters mapped onto discharge hydrographs reveal details of the internal flow system. The chemistry of speleothem deposi­tion is well understood at the level of bulk processes but much has been learned of the surface chemistry on an atomic scale by use of the atomic force microscope. Least well understood is the chemistry of hypogenetic karst. The main chemical reac­tions are known but equilibrium modeling could be improved and reaction kinetics are largely unknown.


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