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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 gorge is a narrow passage or canyon in a mountain system [16]. see also canyon.?

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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;
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Your search for tracers (Keyword) returned 100 results for the whole karstbase:
Showing 91 to 100 of 100
Radon and CO2 as natural tracers to investigate the recharge dynamics of karst aquifers, 2011, Savoy Ludovic, Surbeck Heinz, Hunkeler Daniel

This study investigated the use of radon (222Rn), a radioactive isotope with a half-life of 3.8 days, and CO2 as natural tracers to evaluate the recharge dynamics of karst aquifer under varying hydrological conditions. Dissolved 222Rn and carbon dioxide (CO2) were measured continuously in an underground stream of the Milandre test site, Switzerland. Estimated soil water 222Rn activities were higher than baseflow 222Rn activities, indicating elevated 222Rn production in the soil zone compared to limestone, consistent with a 226Ra enrichment in the soil zone compared to limestone. During small flood events, 222Rn activities did not vary while an immediate increase of the CO2 concentration was observed. During medium and large flood events, an immediate CO2 increase and a delayed 222Rn activity increase to up to 4.9 Bq/L and 11 Bq/L, respectively occurred. The detection of elevated 222Rn activities during medium and large flood events indicate that soil water participates to the flood event. A soil origin of the 222Rn is consistent with its delayed increase compared to discharge reflecting the travel time of 222Rn from the soil to the saturated zone of the system via the epikarst. A three-component mixing model suggested that soil water may contribute 4–6% of the discharge during medium flood events and 25–43% during large flood events. For small flood events, the water must have resided at least 25 days below the soil zone to explain the background 222Rn activities, taking into account the half-life of 222Rn (3.8 days). In contrast to 222Rn, the CO2 increase occurred simultaneously with the discharge increase. This observation as well as the CO2 increase during small flood events, suggests that the elevated CO2 level is not due to the arrival of soil water as for 222Rn. A possible explanation for the CO2 trend is that baseflow water in the stream has lower CO2 levels due to gas loss compared to water stored in low permeability zones. During flood event, the stored water is more rapidly mobilised than during baseflow with less time for gas loss. The study demonstrates that 222Rn and CO2 provides value information on the dynamics of groundwater recharge of karst aquifer, which can be of high interest when evaluating the vulnerability of such systems to contamination.


Radon and CO2 as natural tracers to investigate the recharge dynamics of karst aquifers, 2011, Savoy Ludovic, Surbeck Heinz, Hunkeler Daniel

This study investigated the use of radon (222Rn), a radioactive isotope with a half-life of 3.8 days, and CO2 as natural tracers to evaluate the recharge dynamics of karst aquifer under varying hydrological conditions. Dissolved 222Rn and carbon dioxide (CO2) were measured continuously in an underground stream of the Milandre test site, Switzerland. Estimated soil water 222Rn activities were higher than baseflow 222Rn activities, indicating elevated 222Rn production in the soil zone compared to limestone, consistent with a 226Ra enrichment in the soil zone compared to limestone. During small flood events, 222Rn activities did not vary while an immediate increase of the CO2 concentration was observed. During medium and large flood events, an immediate CO2 increase and a delayed 222Rn activity increase to up to 4.9 Bq/L and 11 Bq/L, respectively occurred. The detection of elevated 222Rn activities during medium and large flood events indicate that soil water participates to the flood event. A soil origin of the 222Rn is consistent with its delayed increase compared to discharge reflecting the travel time of 222Rn from the soil to the saturated zone of the system via the epikarst. A three-component mixing model suggested that soil water may contribute 4–6% of the discharge during medium flood events and 25–43% during large flood events. For small flood events, the water must have resided at least 25 days below the soil zone to explain the background 222Rn activities, taking into account the half-life of 222Rn (3.8 days). In contrast to 222Rn, the CO2 increase occurred simultaneously with the discharge increase. This observation as well as the CO2 increase during small flood events, suggests that the elevated CO2 level is not due to the arrival of soil water as for 222Rn. A possible explanation for the CO2 trend is that baseflow water in the stream has lower CO2 levels due to gas loss compared to water stored in low permeability zones. During flood event, the stored water is more rapidly mobilised than during baseflow with less time for gas loss. The study demonstrates that 222Rn and CO2 provides value information on the dynamics of groundwater recharge of karst aquifer, which can be of high interest when evaluating the vulnerability of such systems to contamination.


Water Tracing in Karst Aquifers, 2012, Jones, William K.

Water tracer tests are usually conducted to establish the hydrologic connections between two or more points. The tracer is an identifiable label or marker added to flowing water that establishes the links between the injection point of the tracer and the monitoring points where the tracer reappears. Fluorescent dyes are the most commonly used tracers in karst aquifers, but a wide range of substances has been used successfully. The experimental design of a tracer test may be qualitative to simply establish if a hydrologic connection exists between two points, or quantitative to measure the time-concentration series (breakthrough curve) generated by the recovery of the tracer. Water tracer tests usually work well in karst areas because of the fast groundwater flow rates and the prevalence of flow paths restricted to discrete conduits.


Radionuclides as natural tracers for the characterization of fluids in regional discharge areas, Buda Thermal Karst, Hungary, 2012, Eross A. , Mdlszonyi J. , Surbeck H. , Horvth . , Goldscheider N. , Csoma A. .

The Buda Thermal Karst (Budapest, Hungary) developed in the regional discharge zone of a carbonate rock aquifer system. High radioactivity of the spring waters has already been reported in 1912, but there has been no detailed study and no consistent explanation for its origin. In this area mixing of cold and hot karst waters was hitherto assigned to be responsible for cave formation. However, the dissimilarity of the discharging waters within Budapest (in the North: Rozsadomb; in the South: Gellert Hill), may suggest also different cave forming processes. The application of radionuclides as natural tracers represents a novel approach to investigate these questions. For this study, we used uranium, radium and radon to identify mixing of fluids in the Buda Thermal Karst system and to infer the temperature and chemical composition of the end members. Chloride as a conservative component allowed the mixing ratios for the sampled waters to be calculated. Their fluid compositions were modeled and through the comparison of modeled and measured values, the end members were validated. As the result of this study, it was possible to characterize the mixing end members for the Rozsadomb area, whereas for the Gellert Hill discharge zone, mixing components could not be identified with the aid of radionuclides. Therefore, it is suggested that different processes are responsible for cave formation in these areas. In the Rozsadomb area, structurally-controlled mixing is the dominant cave forming process, whereas in the Gellert Hill area, due to the lack of mixing members, other processes have to be found, which are responsible for the formation of the caves, such as retrograde calcite solubility and/or geogenic acids, such as H2S. The application of radionuclides thus further supported the differences between the two study areas. This study identified moreover the source of elevated radon content of the waters in the Gellert Hill area in form of iron-hydroxide precipitates that accumulate in the spring caves. These precipitates are highly efficient in adsorbing radium, which generates radon by alpha decay, and hence act as local radon source for the waters. In this study we showed that uranium, radium and radon naturally occurring in groundwater can be used to characterize fluids of different flow systems in regional discharge areas owing to the contrasting geochemical behaviors of these elements


Comparison of discharge, chloride, temperature, uranine, dD, and suspended sediment responses from a multiple tracer test in karst, 2013, Luhmann A. J. , Covington M. D. , Alexander S. C. , Chai S. Y. , Schwartz B. F. , Groten J. T. , Alexander Jr. E. C.

A controlled recharge event with multiple tracers was conducted on August 30, 2010. A pool adjacent to a sinkhole was filled with approximately 13,000 L of water. The water was heated, and salt, deuterium oxide, and uranine were added. The pool was then emptied into the sinkhole, and data were collected at Freiheit Spring approximately 95 m north of the sinkhole to monitor changes in discharge, temperature, conductivity/chloride, dD, uranine, and suspended sediment. This combined trace demonstrated the feasibility and utility of conducting superimposed physical, chemical, and isotopic traces. Flow peaked first at the spring and was followed by a suspended sediment peak; then essentially identical uranine, chloride, and dD peaks; and finally a temperature peak. The initial increase in flow at the spring recorded the time at which the water reached a submerged conduit, sending a pressure pulse to the spring at the speed of sound. The initial increase in uranine, chloride, and dD at the spring recorded the arrival of the recharge water. The initial change in temperature and its peak occurred later than the same parameters in the uranine, chloride, and dD breakthrough curves. As water flowed along this flow path, water temperature interacted with the aquifer, producing a delayed, damped thermal peak at the spring. The combination of conservative and nonconservative tracers illustrates unique pressure, advective, and interactive processes.


Radionuclides as natural tracers for identification of mixing of thermal waters, 2013, Erő, Ss Anita, Mdlsző, Nyi Judit, Horvth kos, Goldscheider Nico

Radionuclides as natural tracers for identification of mixing of thermal waters, 2013, Erő, Ss Anita, Madlsző, Nyi Judit, Horvath Akos, Goldscheider Nico

Forty years of epikarst: what biology have we learned?, 2013, Pipan T. , Culver D. C.

Epikarst is not only an important component of the hydrogeology of karst and an active site of speleogenesis, it is habitat for a number of species adapted to subterranean life. Water in epikarst, with a residence time of days to months, is a highly heterogeneous habitat, and the animals are primarily sampled from continuously sampling dripping water or collecting from residual drip pools. While the subterranean fauna of cracks and crevices has been known for over 100 years, it is only in the past several decades that epikarst has been recognized as a distinct habitat, with reproducing populations of stygobionts. Dissolved organic carbon in epikarst drip water is a primary and sometimes the only source of organic matter for underlying caves, especially if there are not sinking streams that enter the cave. Typical concentrations of organic carbon are 1 mg L-1. The fauna of epikarst is dominated by copepods, but other groups, including some terrestrial taxa, are important in some areas. Most of the diversity is β-diversity (between drips and between caves). In Slovenia, an average of nearly 9 stygobiotic copepod species were found per cave. In studies in Romania and Slovenia, a number of factors have been found to be important in determining species distribution, including ceiling thickness, habitat connectivity and habitat size. In addition to eye and pigment loss, epikarst copepod species may show a number of specializations for life in epikarst, including adaptations to avoid displacement by water flow. Several geoscientists and biologists have challenged the uniqueness and importance of epikarst, but on balance the concept is valid and useful. Fruitful future research directions include development of better sampling techniques, studies to explain differences among nearby epikarst communities, phylogeographic studies, and assessing the possible role of copepods as tracers of vadose water.


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.


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.

 


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