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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 erosion is 1. the general process or group of processes whereby the materials of the earth's crust are moved from one place to another by running water (including rainfall), waves and currents, glacier ice, or wind [6]. 2. the sequence of processes of disintegration and transportation of rock material [16].?

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

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KarstBase a bibliography database in karst and cave science.

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;
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Your search for aquifers (Keyword) returned 730 results for the whole karstbase:
Showing 721 to 730 of 730
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.


Hydrogeology of northern Sierra de Chiapas, Mexico: A conceptual model based on a geochemical characterization of sulfide-rich karst brackish springs, 2014,

Conspicuous sulfide-rich karst springs flow from Cretaceous carbonates in northern Sierra de Chiapas, Mexico. This is a geologically complex, tropical karst area. The physical, geologic, hydrologic and chemical attributes of these springs were determined and integrated into a conceptual hydrogeologic model. A meteoric source and a recharge elevation below 1500 m are estimated from the spring water isotopic signature regardless of their chemical composition. Brackish spring water flows at a maximum depth of 2000 m, as inferred from similar chemical attributes to the produced water from a nearby oil well. Oil reservoirs may be found at depths below 2000 m. Three subsurface environments or aquifers are identified based on the B, Li+, K+ and SiO2 concentrations, spring water temperatures, and CO2 pressures. There is mixing between these aquifers. The aquifer designated Local is shallow and contains potable water vulnerable to pollution. The aquifer named Northern receives some brackish produced water. The composition of the Southern aquifer is influenced by halite dissolution enhanced at fault detachment surfaces. Epigenic speleogenesis is associated with the Local springs. In contrast, hypogenic speleogenesis is associated with the brackish sulfidic springs from the Northern and the Southern environments.


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.

 


The hydrogeology of high-mountain carbonate areas: an example of some Alpine systems in southern Piedmont (Italy), 2015,

The hydrogeological characteristics of some springs supplied by high-mountain carbonate rock aquifers, located in the south of Piedmont, in Italy, are presented in this work. The aquifers have different geological-structural conditions, including both deep and superficial karstification. Their catchment areas are located in a typical Alpine context at a high altitude of about 2000 m. These aquifers are ideal representations of the different hydrogeological situations that can be encountered in the high-altitude carbonate aquifers of the Mediterranean basin. It is first shown how the high-altitude zones present typical situations, in particular related to the climate, which control the infiltration processes to a great extent. Snowfall accumulates on the ground from November to April, often reaching remarkable thicknesses. The snow usually begins to melt in spring and continues to feed the aquifer for several months. This type of recharge is characterized by continuous daily variations caused by the typical thermal excursions. The hourly values are somewhat modest, but snowmelt lasts for a long time, beginning in the lower sectors and ending, after various months, in the higher areas. Abundant rainfall also occurs in the same period, and this contributes further to the aquifer supply. In the summer period, there is very little rainfall, but frequent storms. In autumn, abundant rainfall occurs and there are there fore short but relevant recharge events. It has been shown how the trend of the yearly flow of the high mountain springs is influenced to a great extent by the snowmelt processes and autumn rainfall. It has also been shown, by means of the annual hydrographs of the flow and the electric conductivity of the spring water, how the different examined aquifers are characterized by very different measured value trends, according to the characteristics of the aquifer.

 


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.


Sulfuric acid speleogenesis (SAS) close to the water table: Examples from southern France, Austria, and Sicily, 2015,

Caves formed by rising sulfuric waters have been described from all over the world in a wide variety of climate  settings, from arid regions to mid-latitude and alpine areas. H2S is generally formed at depth by reduction of  sulfates in the presence of hydrocarbons and is transported in solution through the deep aquifers. In tectonically  disturbed areas major fractures eventually allow these H2S-bearing fluids to rise to the surface where oxidation  processes can become active producing sulfuric acid. This extremely strong acid reacts with the carbonate  bedrock creating caves, some of which are among the largest and most spectacular in the world. Production of  sulfuric acid mostly occurs at or close to the water table but also in subaerial conditions in moisture films and  droplets in the cave environment. These caves are generated at or immediately above the water table, where  condensation–corrosion processes are dominant, creating a set of characteristic meso- and micromorphologies.  Due to their close connection to the base level, these caves can also precisely record past hydrological and  geomorphological settings. Certain authigenic cave minerals, produced during the sulfuric acid speleogenesis  (SAS) phase, allow determination of the exact timing of speleogenesis. This paper deals with the morphological,  geochemical and mineralogical description of four very typical sulfuric acid water table caves in Europe: the  Grotte du Chat in the southern French Alps, the Acqua Fitusa Cave in Sicily (Italy), and the Bad Deutsch Altenburg  and Kraushöhle caves in Austria


Engineering challenges in Karst, 2015,

Anisotropy and heterogeneity of karstified rocks make them the most problematic media for various interventions which are needed in engineering practice. The long history of attempts to adapt karstic nature to human needs started with the utilization of karstic aquifers: tapping large springs, transferring their waters to the long distances, improving minimal flows or capturing fresh water in coastal areas. During the 20th century the number of other challenges such as building dam and reservoirs, and constructing roads and railways, bridges, tunnels, new settlements open a new era in engineering works but also in collecting new knowledge and experience for the karstology and hydrogeology sciences. Today, almost no engineering projects can be implemented without a proper environmental impact assessment, which establishes a better balance between human and ecological needs. 


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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