Community news

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 induced activity is the activity or response of a system that has been subjected to an artificial excitation [16].?

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

What is Karstbase?

Search KARSTBASE:

keyword
author

Browse Speleogenesis Issues:

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;
See all featured articles from other geoscience journals

Search in KarstBase

Your search for natural tracer (Keyword) returned 22 results for the whole karstbase:
Showing 1 to 15 of 22
Radon transport phenomena studied in Karst caves-international experiences on radon levels and exposures, 1997, Hakl J. , Hunyadi I. , Csige I. , Geczy G. , Lenart L. , Varhegyi A. ,
The results of radon measurements in caves obtained by using of nuclear track detectors are summarized. Mean radon concentrations are ranging worldwide from 0.1 to 20 kBqm-3 with 2.8 kBqm-3 arithmetic average. From long-term extended radon measurements in caves not only a detailed dosimetric picture can be drawn, but using radon gas as a radioactive tracer, the subsurface and near-to-surface transport processes can be studied, too. It will be shown that long-term radon monitoring by nuclear track detectors, in conjunctions with active detectors which enables detection of fast dynamic changes, offers very important information for naturally-occurring transport processes

River water intrusion to the unconfined Floridan Aquifer, 1998, Kincaid Todd R. ,
Rapid infiltration of river water into unconfined parts of the Floridan aquifer represents a significant component of subsequent ground-water discharge in regions where the aquifer is dissected by surface streams. A two-year investigation of the Devil's Ear cave system, an extensive saturated conduit network in the Floridan aquifer which underlies a 1.5-km reach of the Santa Fe River in north-central Florida, revealed that there is an appreciable and rapid exchange of water between the river and the underlying Floridan aquifer. Natural tracers Radon-222 ( 222 Rn) and delta 18 O were used to quantify these exchanges. Cave diving was employed to collect 50 water samples which were analyzed for tracer content and to observe water clarity conditions within the saturated karst conduits as far as 1.2 km from the cave entrance. 222 Rn concentrations measured in the cave system revealed three distinct zones where river water is rapidly intruded into the Floridan aquifer. A two-component mixing model was used to quantify the intruded river water that was found to account for as much as 62 percent of the discharge at Devil's Ear spring. Observations of diminished water clarity in the cave system following large precipitation events in the highland provinces of the Santa Fe River basin indicate that river water intrusion to the aquifer can occur in as little as one or two days. The results of this investigation imply that, in regions such as the western Santa Fe River basin, there can be no clear distinction between ground and surface waters and intruded river water provides a significant vehicle for contamination of the unconfined Floridan aquifer

Stable isotopes as natural tracers of the karst recharge to the tertiary clastic aquifers: a case study of southern part of Ljubljana marsh , 1998, Pezdič, Jož, E,

The main purpose of the research was to determine the recharge and storage of groundwater at the southern part of Ljubljana marsh where tertiary aquifers are filled mainly with karst water. Stable isotopes of hydrogen, oxygen and carbon in water or in dissolved species, as well as tritium content in water and precipitation were used as natural tracers to follow the recharge and discharge of surface streams and aquifers. Together with hydrogeological and other chemical evidence they provide useful information about water mass transport, storage, refilling of aquifers and mixing of groundwater. In the aquifers, springs and surface river water d18O varied from -9,65 to -8,82 š while dD has the range from -67,4 to -61,2 š. Tritium activities are measured from 1,6 to 13,4 T.U.. Long term averages (n = 13 years) for d18O (dD) in Ljubljana is -8,73 (-60,6) š and tritium content is 17,5 T.U.. The mean temperature in Ljubljana is 10,03ºC and average years precipitation amount is 1332 mm. Years 1992-93 have been characterised by low tritium content in precipitation (8,2 for 1992 and 10,6 for 1993) and so important for investigation. The average mean meteoric line for the last 14 years is defined as dD=8,188xd18O+10,66. Temperature correlation vs. oxygen is: d18O=0,254xt-10,78. The above database is discussed in order to evaluate thesis about karst influence on the recharge and storage of clastic sediment aquifers in the Iška delta sediment structure.


Hydrochemical evidence for mixing of river water and groundwater during high-flow conditions, lower Suwannee River basin, Florida, USA, 1999, Crandall Ca, Katz Bg, Hirten Jj,
Karstic aquifers are highly susceptible to rapid infiltration of river water, particularly during periods of high flow. Following a period of sustained rainfall in the Suwannee River basin, Florida, USA, the stage of the Suwannee River rose from 3.0 to 5.88 m above mean sea level in April 1996 and discharge peaked at 360 m(3)/s. During these high-now conditions, water from the Suwannee River migrated directly into the karstic Upper Floridan aquifer, the main source of water supply for the area. Changes in the chemical composition of groundwater were quantified using naturally occurring geochemical tracers and mass-balance modeling techniques. Mixing of river water with groundwater was indicated by a decrease in the concentrations of calcium, silica, and Rn-222; and by an increase in dissolved organic carbon (DOC), tannic acid, and chloride, compared to low-flow conditions in water from a nearby monitoring well, Wingate Sink, and Little River Springs. The proportion (fraction) of river water in groundwater ranged from 0.13 to 0.65 at Wingate Sink and from 0.5 to 0.99 at well W-17258, based on binary mixing models using various tracers. The effectiveness of a natural tracer in quantifying mixing of river water and groundwater was related to differences in tracer concentration of the two end members and how conservatively the tracer reacted in the mixed water. Solutes with similar concentrations in the two end-member waters (Na, Mg, K, Cl, SO4, SiO2) were not as effective tracers for quantifying mixing of river water and groundwater as those with larger differences in end-member concentrations (Ca, tannic acid, DOC, Rn-222, HCO3)

Temperature as a natural tracer of short residence times for groundwater in karst aquifers, 1999, Martin J. B. , Dean R. W.
Chemistry of karst waters is controlled by reactions with aquifer rocks, the extent of mixing between water sources, and variations in the composition of recharged waterThe extent of reactions and mixing may be determined uniquely if compositions of both recharged and discharged water are known, such as where sinking streams are linked to resurgent springs, and if residence time in the subsurface can be measuredSuch a linked system occurs along the Santa Fe River in north-central Florida, where the river flows underground for approximately 52 km as it crosses from confined to unconfined portions of the Floridan AquiferTemporal variations in temperature can be correlated between the river sink, the river rise, and Sweetwater Lake, a karst window approximately midway between the sink and riseDelays in the arrival time of temperature maxima and minima from the sink to Sweetwater Lake and from Sweetwater Lake to the Rise reflect the residence time of the river water in the subsurfaceResidence time correlates with the river stage and ranges from approximately 12 hours to more than four days at high and low stage, respectively between the river sink and SweetwaterLake, and from about six hours to nearly two days at high and low stage, respectively, between Sweetwater Lake and the river riseThese short residence times reflect minimum flow rates of between 13 and 9 km/day, indicating conduit flowKnowing the residence time at any stage allows sampling of water as it enters the aquifer, and then again as it dischargesChanges in the chemistry of water as it passes through the subsurface should reflect chemical reactions, mixing, or both

The suitability of carbon isotope composition as natural tracer in karst aquifer investigations, 2000, Trč, Ek Branka, Veselič, Miran, Urbanc Janko

This isotopic research is ongoing in the catchment area of the karstic spring Hubelj in the area of the Trnovsko-Banjška plateau. Changes in water chemistry and carbon isotope composition are monitored from the aquifer recharge area in precipitation water, through the unsaturated zone to the outflow from the aquifer. Special attention is given to the unsaturated zone. The results confirm that the sampled water is equilibrated with the carbonate rock and that the process of carbonate rock dissolution can be described as an open dissolution system.


Inverse modeling of the hydrological and the hydrochemical behavior of hydrosystems: Characterization of karst system functioning, 2001, Pinault J. L. , Plagnes V. , Aquilina L. , Bakalowicz M. ,
Inverse modeling of mass transfer characterizes the dynamic processes affecting the function of karst systems and can be used to identify karst properties. An inverse model is proposed to calculate unit hydrographs as well as impulse response of fluxes from rainfall-runoff or rainfall-flux data, the purpose of which is hydrograph separation. Contrary to what hydrologists have been doing for years, hydrograph separation is carried out by using transfer functions in their entirety, which enables accurate separation of fluxes, as was explained in the companion paper [Pinault et al., this issue]. The unit hydrograph as well as impulse response of fluxes is decomposed into a quick and a slow component, and, consequently, the effective rainfall is decomposed into two parts, one contributing to the quick flow (or flux) and the other contributing to the slow flow generation. This approach is applied to seven French karstic aquifers located on the Larzac plateau in the Grands Causses area (in the south of France). Both hydrodynamical and hydrogeochemical data have been recorded from these springs over several hydrological cycles. For modeling purposes, karst properties can be represented by the impulse responses of flow and flux of dissolved species. The heterogeneity of aquifers is translated to time-modulated flow and transport at the outlet. Monitoring these fluxes enables the evaluation of slow and quick components in the hydrograph. The quick component refers to the 'flush flow' effect and results from fast infiltration in the karst conduit network when connection is established between the infiltration and phreatic zones, inducing an increase in water head. This component reflects flood events where flow behavior is nonlinear and is described by a very short transfer function, which increases and decreases according to water head. The slow component consists of slow and fast infiltration, underground runoff, storage in annex-to-drain systems, and discharge from the saturated zone. These components can be further subdivided by measuring chemical responses at the karst outlet. Using Such natural tracers enables the slow component of the unit hydrograph to be separated into preevent water, i.e., water of the reservoir and event water, i.e., water whose origin can be related to a particular rainfall event. These measurements can be used to determine the rate of water renewal. Since the preevent water hydrograph is produced by stored water when pushed by a rainfall event and the event water hydrograph reflects rainwater transfer, separating the two components can yield insights into the characteristics of karst aquifers, the modes of infiltration, and the mechanisms involved in karstification, as well as the degree of organization of the aquifer

Characterising karst aquifer function by inverse modelling of natural tracers, 2001, Bakalowicz M. , Pinault Jl. , Plagnes V.

A conceptual model of flow and transport in a karst aquifer based on spatial and temporal variations of natural tracers, 2003, Perrin, Jerome

Karst aquifers represent an important groundwater resource world-wide. They are highly vulnerable to contamination due to fast transport through the system and limited attenuation of contaminants. The two main hydrogeological approaches developed for studying flow and transport are: inference of the
system structure from karst spring hydrographs and chemographs; numerical modelling of flow and transport using a theoretical distribution of flow and transport field parameters. These two approaches lack of validation by detailed field measurements and observations. The main objective of this thesis is to “fill the gap” existing between field and model data. Observations of flow and transport parameters at several locations within the system were used to develop a conceptual model. This model was then compared to the existing models.
The main field test site is the Milandre karst aquifer, located in the Swiss tabular Jura. Natural tracers (major ions, oxygen-18, specific conductance) and discharge were measured on the underground river, its main tributaries, percolation waters, and the main spring. These data were collected on a long-term basis in order to assess the spatial variability of the parameters, and on a short time scale (i.e. flood events) in order to investigate the dynamic processes. Complementary sites (Brandt and Grand Bochat) were used for more observations at the base of the epikarst.
The proposed conceptual model considers four sub-systems: the soil zone, the epikarst, the unsaturated zone, and the phreatic zone. Each has its own specificity with respect to flow and transport. The soil zone controls the actual infiltration into the system. It contributes efficiently to groundwater storage. It mixes quickly stored water with fresh infiltrated water. Its thickness determines land-use: thick soils are generally cultivated whereas thin soils are under forested areas. The solutes concentration of soil waters depends on land-use for pollution-related parameters (nitrate, chloride, sulfate, potassium, sodium). Moreover the soil zone is the main source of CO2 which controls the limestone dissolution-related parameters. The epikarst zone contributes largely to groundwater storage. It distributes groundwater into vadose flow through conduits, and base flow through low permeability volumes (LPV) in the unsaturated zone. It is the sub-system where dissolution-related parameters are mostly acquired.
The unsaturated zone is seen as a transmissive zone connecting the epikarst to the horizontal conduit network of the phreatic zone. In case of flood events, some dissolution still occurs in this sub-system.
The phreatic zone is the partly flooded conduit network draining groundwater to the spring. It collects waters issued from the unsaturated zone, mixes the tributaries, and drain the water towards the discharge area. The role of phreatic storage appears to be limited for both hydraulics and transport.
Tributary mixing is a prominent process that shapes spring chemographs during flood events. In steady-state conditions, base flow is mainly sustained by the epikarst reservoir. Tracer concentrations are stable as the chemical equilibrium is already reached in the epikarst. Waters issued from the different tributaries mix in the conduit network, and the spring chemistry is the result of this mixing.
During flood events, transient flow induces non-linear mixing of the tributaries. The respective contributions of the tributaries change throughout the flood, and the spring chemographs vary accordingly. In case of important recharge, waters issued from other sources than the epikarst participate to the flood. First, soil water reaches the phreatic zone. Its characteristics are a dampened isotopic signal, and ionic concentrations differing from those of the epikarst. Second, fresh water directly issued from rainfall, may reach the phreatic zone. Its characteristics are a varying isotopic signal, and diluted ionic concentrations. The mixing components participating to the flood are controlled by the actual infiltration volume (or height). The limestone dissolution process is effective for the fresh and soil components of flow. However mixing processes play a more important role than dissolution for shaping the spring chemographs.
From a practical point of view, the project confirmed the prominent role of the soil zone and the epikarst on the solute transport in karst systems. This was already integrated in karst vulnerability mapping methods recently developed (EPIK, PI, VULK).

http://doc.rero.ch/record/2604/files/these_PerrinJ.pdf


The vulnerability of karst springs - a case study of the Hubelj spring (SW Slovenia), 2006, Trcek B. , Veselic M. , Pezdic J. ,
The hydraulic behaviour of the karst aquifer in the Hubelj spring catchment area (SW Slovenia) was studied by using an indirect research method based on natural tracers. The variations of natural tracers (in precipitation and in groundwater) during the storm event made possible the separation of the Hubelj spring storm hydrograph by the three-component separation technique. The results produced information on the aquifer recharge, storage and discharge processes, as well as on the mechanisms that affected them. They verified the so-called epikarst hypothesis presuming that an important part of a karst aquifer recharge reaches rapidly and intensively from the epikarst zone. It was demonstrated that epikarst water could occupy up to 50% of the spring discharge during precipitation events. This phenomenon could have important consequences on protection and management of the problems of karst aquifers, including engineering problems in karst areas. With this respect the results could give way to new engineering ideas

Les Microcodium: un traceur naturel des coulements karstiques dans les craies champenoises proximit des formations palocnes (Marne, France)., 2007, Lejeune O. , Devos A. , Fronteau G. , Roche D. , Lefevre A. , Sosson C.
The microcodium: A natural tracer of karstic flowpaths in the Champagne chalk close to the Paleocene formations (Marne, France) - Our study group GEGENA was asked to study the karstic flowpaths witin the Champagne chalk. This work was done within a research program (AQUAL) investigating the agricultural pollutions within the Vesle basin. The absence of good conditions to conduct classical dye tracing experiments led us to search for a natural tracer to prove that karstic circulations do exist. A stratigraphic study permitted to isolate a microcodium fossil, present in the upper parts of the Campagnian chalks, which could be a natural tracer for the chalk karst area around the Montagne de Reims. This tracer is locally associated with archeological elements which permit to state that the flow is karstic. The Trpail spring was used as a test site for the validation of the method. The sediments collected in the spring as well as in other springs nearby do indeed contain many microcodium remains.

How can the epikarst zone influence the karst aquifer hydraulic behaviour?, 2007, Trcek Branka
The role of an epikarst zone in the karst aquifer hydraulic behaviour was brought into focus in our studies referring to the catchment area of the Hubelj spring (SW Slovenia). This study points out the significance of effects of the fast preferential flow?epiflow, which is the main factor controlling solute/contaminant transport towards the aquifer saturated zone. The so-called epikarstic hypothesis is verified on the basis of the most significant research results that are supported by the most important findings from the literature.

CHARACTERISTICS OF PERCOLATION THROUGH THE KARST VADOSE ZONE, 2010, Kogovš, Ek Janja

The study of the vadose zone has been based on 35 years research of underground water circulation and the transfer of contaminants in karst and on continuous long-term measurements and analyses of precipitation on the surface and of several representative trickles in the vadose zone of Postojna Cave over consecutive hydrological years and it offers an explanation of the dynamics of the percolation of water and simultaneous transfer of contaminants and their impact on the dissolution of carbonate rock in the vadose zone. Emphasis is placed on a multi-parameter approach based on the simultaneous use of a number of different methods, not only tracing natural tracers but also tests with artificial tracers using different methods of injection. The research contributs to the understanding of the role of the vadose zone in the karst aquifer.


Karst Groundwater Management through Science and Education, 2011, Guo Fang, Jiang Guanghui

In Southwestern China, karst covers an area of 540,000 km2, and supports a population of approximately 100 million people. This groundwater can easily become highly polluted without effective management. Sound management of karst areas requires the conscientious participation of citizens including homeowners, planners, government officials, farmers and other land-use decision makers. Lingshui Spring was a good example. A series of educational materials were developed and delivered to the local government, residents, and students. A groundwater polluted accident was tracked as a natural tracer test in a spring to increase understanding of the vulnerability of the area’s karst aquifer. More than 200 people attended the communication and training course on groundwater protection and environmental justice law. Several efforts have appeared as a result, such as a proposal for Lingshui water resources protection that was put forward for the first time by Wuming county political consultative conference


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.


Results 1 to 15 of 22
You probably didn't submit anything to search for