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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. ...

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That heterogeneous is the unequal spacial distribution of aquifer properties [16].?

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Karst environment, Culver D.C.
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Calculating flux to predict future cave radon concentrations, Rowberry, Matt; Marti, Xavi; Frontera, Carlos; Van De Wiel, Marco; Briestensky, Milos
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Your search for tracer test (Keyword) returned 92 results for the whole karstbase:
Showing 1 to 15 of 92
Predicting travel times and transport characterization in karst conduits by analyzing tracer-breakthrough curves, , Morales Tomas, De Valderrama Inigo, Uriarte Jesus A. , Antiguedad Inaki, Olazar Martin,
SummaryThis paper analyzes data obtained in 26 tracer tests carried out in 11 karstic connections following solutional conduits in karst aquifers in the Basque Country. These conduits are preferential drainage pathways in these aquifers and so they confer a marked anisotropy and high vulnerability to them. Consequently, their consideration in protection and management studies and projects is a priority.The connections studied cover a wide hydrogeological spectrum (a wide range of sizes, slopes, geomorphic and hydrologic types) and the tests have been carried out at different hydrodynamic states. It is noteworthy that they all follow a similar trend, which has allowed for the development of a statistical approximation for the treatment of the whole information.Relationships have been established involving velocity, solute time of arrival, attenuation of peak concentration and time of passage of tracer cloud. These relationships are a valuable tool for management and supporting decision-making and allow for making estimates in connections in which the information available was scarce. This information is especially useful, given that the complexity of transport in karst conduits gives way to important deviations between real data (empirical observations) and the data obtained by simple approaches based on the Fickian-type diffusion equation

Transport and variability of fecal bacteria in carbonate conglomerate aquifers, , Goeppert N. , Goldscheider N.

Clastic sedimentary rocks are generally considered non-karstifiable and thus less vulnerable to pathogen contamination than karst aquifers. However, dissolution phenomena have been observed in clastic carbonate conglomerates of the Subalpine Molasse zone of the northern Alps and other regions of Europe, indicating karstification and high vulnerability, which is currently not considered for source protection zoning. Therefore, a research program was established at the Hochgrat site (Austria/Germany), as a demonstration that karst-like characteristics, flow behavior and high vulnerability to microbial contamination are possible in this type of aquifer. The study included geomorphologic mapping, comparative multi-tracer tests with fluorescent dyes and bacteria-sized fluorescent microspheres, and analyses of fecal indicator bacteria (FIB) in spring waters during different seasons. Results demonstrate that (i) flow velocities in carbonate conglomerates are similar as in typical karst aquifers, often exceeding 100 m/h; (ii) microbial contaminants are rapidly transported towards springs; and (iii) the magnitude and seasonal pattern of FIB variability depends on the land use in the spring catchment and its altitude. Different ground water protection strategies than currently applied are consequently required in regions formed by karstified carbonatic clastic rocks, taking into account their high degree of heterogeneity and vulnerability.

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Anomalous behaviour of specific electrical conductivity at a karst spring induced by variable catchment boundaries: the case of the Podstenjšek spring, Slovenia, , Ravbar, N. , Engelhardt, I. , Goldscheider, N.

Anomalous behaviour of specific electrical conductivity (SEC) was observed at a karst spring in Slovenia during 26 high-flow events in an 18-month monitoring period. A conceptual model explaining this anomalous SEC variability is presented and reproduced by numerical modelling, and the practical relevance for source protection zoning is discussed. After storm rainfall, discharge increases rapidly, which is typical for karst springs. SEC displays a first maximum during the rising limb of the spring hydrograph, followed by a minimum indicating the arrival of freshly infiltrated water, often confirmed by increased levels of total organic carbon (TOC). The anomalous behaviour starts after this SEC minimum, when SEC rises again and remains elevated during the entire high-flow period, typically 20–40 µS/cm above the baseflow value. This is explained by variable catchment boundaries: When the water level in the aquifer rises, the catchment expands, incorporating zones of groundwater with higher SEC, caused by higher unsaturated zone thickness and subtle lithologic changes. This conceptual model has been checked by numerical investigations. A generalized finite-difference model including high-conductivity cells representing the conduit network (“discrete-continuum approach”) was set up to simulate the observed behaviour of the karst system. The model reproduces the shifting groundwater divide and the nearly simultaneous increase of discharge and SEC during high-flow periods. The observed behaviour is relevant for groundwater source protection zoning, which requires reliable delineation of catchment areas. Anomalous behaviour of SEC can point to variable catchment boundaries that can be checked by tracer tests during different hydrologic conditions.


CONVOLUTION IN TIME-DEPENDENT SYSTEM FROM ARTIFICIAL TRACER TESTS RESPONSES IN POROUS OR KARST SYSTEMS - THEORY AND MODELING, 1995, Dzikowski M,
An instantaneous point injection of an artificial tracer makes it possible to identify the studied system directly. Whether or not convolutions can be carried out depends on the linearity and stationarity of the tracer-test system. Convolutions from the relations between the impulse responses and the hydrodynamic conditions in time-dependent systems are only allowed under special conditions. The framework in which such convolutions are possible is established and a convolution integral proposed which makes it possible to obtain the result of any input in time at one of the outlets of a vectorial system when an artificial tracer test has been carried out between the injection point and this outlet. A few theoretical examples of convolution results with variable flow rates are presented; these results were obtained with a computer code based on the proposed convolution integral

Convolution a debit variable a partir des reponses de tracages artificiels; application a un systeme karstique (Causse de Gramat, Lot, France): Convolution in time-dependent system from artificial tra, 1995, Dzikowski M, Delay F, Sauty Jp, Crampon N, De Marsily G,
ResumeLa realisation de tracages artificiels dans des conditions hydrodynamiques differentes sur le systeme karstique de I'Ouysse (Causse de Gamat, France) ainsi que de mesures physicochimiques portant entre autres sur les chlorures, nitrates et matieres en suspension ont permis d'exploiter les possibilites de l'analyse des systemes-tracages dependant du temps. Pour des tracages artificiels realises a des periodes hydrologiques differentes (basses-eaux et hauteseaux), les relations entre les reponses impulsionnelles a l'injection instantanee de traceur et les debits d'ecoulement variables associes sont mises en evidence sur un systeme a deux entrees (pertes de Themines et Theminettes) et une sortie (gouffre de Besaces). Ces relations etablissent une independance entre l'espace occupe par le traceur au cours de son transfert et les conditions hydrodynamiques dans la gamme de debits interessant chaque tracage. Des operations de convolutions d'entrees en chlorures, nitrates et matieres en suspension, basses sur l'hypothese d'un systeme a volume constant dependant du temps ont donc pu etre realisees. Les resultats sont compares au mesures experimentales au point de sortie (Besaces).AbstractArtificial tracer tests conducted under different hydrodynamic conditions on the karst system of Ouysse (Causse de Gramat, France) and chemical measurements have permitted the use of the time-dependent tracer test analysis. For artificial tracer experiments in different hydrologic periods (water rise and high flow), the relationships between the responses to an instantaneous injection are improved in a system defined by two inputs (losses of Themines and Theminettes). They show that the space occupied by the mass of tracer during its transfer can be considered as independent of the discharge according to the range of flow rate in which the tracer experiments have been conducted. Therefore, convolutions on chlorides, nitrates and suspended sediments are simulated under the hypothesis of a constant-volume and time-dependent system. The computed results are compared with the experimental data at the output (cave of Besaces)

Un aquifre gypseux de haute montagne : mesures physico-chimiques et traage dans la valle de Gbroulaz (Vanoise, France), 1996, Dzikowski M. , Nicoud G. , Arfib B. , Paillet A. , Rovera G.
During the high flow period of summer 1995, conductivity and temperature were periodically measured in two losses and five springs along a gypsum and anhydrite outcrop in the Gbroulaz valley. These experiments together with a water chemical analysis and an artificial tracer test have highlighted two kinds of flows through the evaporitic formations. The springs are characterised by a rapid flow directly influenced by the infiltration of melt water in a surficial karst. A slower flow shows a deeper circulation through a saturated and fissured milieu. So, in a high mountainous area, the gypsum layer shows a surficial karst over a fissured aquifer. This interpretation allows us to explain the stability of the physico-chemical parameters for the springs, which are not influenced by karstic flow conditions.

An examination of short-term variations in water quality at a karst spring in Kentucky, 1996, Ryan M. , Meiman J. ,
Water quality at many karst springs undergoes very high amplitude but relatively brief degradation following influxes of runoff. Accurately recording transient variations requires more rigorous sampling strategies than traditional methods, A pilot study to determine the usefulness of high-frequency, flow-dependent sampling strategies, combined with coincidental quantitative dye tracer tests, was implemented in the Big Spring Ground-Water Basin in Mammoth Cave National Park, Kentucky. Data recorded following two separate runoff events showed that the concentrations of two nonpoint source pollutants, fecal coliform bacteria and suspended sediment, greatly exceeded prerunoff event values for very short periods of time, A phreatic conduit segment, calculated at 17 million liters in volume, instantaneously propagated head changes, caused by direct runoff entering the aquifer, from the ground-water inputs to Big Spring, A significant delay between the initial increases in discharge and the arrival of direct runoff, as indicated by a steady decrease in specific conductance, represented the time required to displace this volume of phreatic water, The delay showed that sampling a karst spring only during peak discharge would be an unreliable sampling method. Runoff from two different subcatchments was tagged with tracer dye and the timing of the passage of the resultant dye clouds through Big Spring were compared to water quality variations, Distinct lag times between the arrival of direct runoff at Big Spring and the bacteria and suspended sediment waveforms were shown through the concurrent quantitative tracer tests to be related to the areal distribution of land-cover type within the basin

Discussion on 'The Chalk as a karstic aquifer: evidence from a tracer test at Stanford Dingley, Berkshire, UK': Quarterly Journal of Engineering Geology, 28, S31-S38, 1996, Banks D, Davies C, Davies W,
M. Price writes: Banks et al. (1995) address the nature of the permeability of parts of the Chalk aquifer, provide useful data from a tracer test, and draw attention to the potential dangers of disposing of agricultural and road run-off to swallow holes. The paper includes a calculation of fissure conductivity and aperture from the results of the tracer test. In this it has to be emphasized that the calculations relate to Darcian flow in an equivalent smooth, plane, parallel-plate opening, not the more likely turbulent flow in a natural fissure. The true average aperture of the fissure is therefore likely to be significantly greater than that calculated (Price 1987, 1996). The situation described at Stanford Dingely is one where drainage originating from impermeable Tertiary strata flows onto the Chalk and sinks into the aquifer. The majority of active Chalk sinks appear to be of this type; the drainage sinking into them originates as run-off from other strata. Rain falling anywhere on the outcrop of the Chalk is normally able to infiltrate, so water flowing across the Chalk outcrop is almost invariably allogenic drainage or water that has infiltrated the Chalk and emerged as baseflow. Drainage to sinks is therefore a minor component of recharge to the Chalk. The tracer test undertaken into at Stanford Dingley involved introducing tracer into a known point of entry in the aquifer, and observing its arrival at a known point of emergence. Such tests almost inevitably measure the speed of groundwater movement along a ... This 250-word extract was created in the absence of an abstract

Results of a study about tracing tests transfer functions variability in karst environment, 1997, Doerfliger N.
Artificial tracing tests are often used to simulate migration of a point-source contaminant under various hydrological conditions in karst hydrogeological impact assessment or to define groundwater protection zones. Due to economic reasons, it is rather difficult to carry out adequate tracing tests to determine what are the possible recovery curves over range of discharges at the outlet, are the tracer test results representative of the spring watercatchment being protected ? Our objective was to characterize the tracing-systems in a karst environment by a mean transfer function; such transfer function may be used to predict the breakthrough curve of a point-source contaminant taking into account an error factor. A Jura mean transfer function with + and -95% interval confidence functions can be established and differentiated from the Alps mean transfer function. The use of this transfer function to predict the response of a point-source contaminant requires considerations of water catchment size, thickness or the aquifer and discharge at the outlet. The results of this variability analysis confirm that the transfer functions by themselves may not be used to protect the whole karst spring water catchment, as this one is affected by the heterogeneity of the physical parameters. At the scale of a water catchment, transfer functions are not the major tool to protect the groundwater. But with a multiattribute approach of vulnerability mapping, transfer functions contribute to the development of groundwater protection strategy.

Experimental design, technique and protocol in fluorometric tracing of ground water, 1997, Smart C. C. , Zabo L.
Detector-spectrofluorometer and water-filter fluorometry provide two complementary tools in tracer testing. Current practice largely relies on the former technique, despite some limitations in quality assurance. A set of technical enhancements have been undertaken on the Turner Designs Model 10 Series filter fluorometer to redress this imbalance by improving efficiency. In addition, improvements in protocol are suggested. A preliminary framework for optimal design of tracer tests is presented. Nevertheless, there remain barriers to wider deployment of filter fluorometers, notably in complex traces and borehole tests.

Evidence for rapid groundwater flow and karst-type behaviour in the Chalk of southern England, 1998, Macdonald A. M. , Brewerton L. J. , Allen D. J. ,
With the growing importance of groundwater protection, there is increasing concern about the possibility of rapid groundwater flow in the Chalk of southern England and therefore in the frequency and distribution of karstic' features. Pumping test data, although useful in quantifying groundwater resources and regional flow, give little information on groundwater flow at a local scale. Evidence for rapid groundwater flow is gathered from other, less quantifiable methods. Nine different strands of evidence are drawn together: tracer tests; observations from Chalk caves; Chalk boreholes that pump sand; descriptions of adits; the nature of water-level fluctuations; the Chichester flood; the nature of the surface drainage; geomorphological features; and the presence of indicator bacteria in Chalk boreholes. Although the evidence does not prove the widespread existence of karstic features, it does suggest that rapid groundwater flow should be considered seriously throughout the Chalk. Rapid groundwater flow is generally more frequent close to Palaeogene cover and may also be associated with other forms of cover and valley bottoms

Lanthanide-labeled clay: A new method for tracing sediment transport in karst, 1998, Mahler B. J. , Bennett P. C. , Zimmerman M. ,
Mobile sediment is a fundamental yet poorly characterized aspect of mass transport through karst aquifers. Here the development and field testing of an extremely sensitive particle tracer that may be used to characterize sediment transport in karst aquifers is described. The tracer consists of micron-size montmorillonite particles homoionized to the lanthanide form; after injection and retrieval from a ground water system, the lanthanide ions are chemically stripped from the clay and quantified by high performance liquid chromatography, The tracer meets the following desired criteria: low detection limit; a number of differentiable signatures; inexpensive production and quantification using standard methods; no environmental risks; and hydrodynamic properties similar to the in situ sediment it is designed to trace. The tracer was tested in laboratory batch experiments and field tested in both surface water and ground water systems. In surface water, arrival times of the tracer were similar to those of a conservative water tracer, although a significant amount of material was lost due to settling. Two tracer tests were undertaken in a karst aquifer under different flow conditions. Under normal flow conditions, the time of arrival and peak concentration of the tracer were similar to or preceded that of a conservative water tracer. Under low flow conditions, the particle tracer was not detected, suggesting that in low flow the sediment settles out of suspension and goes into storage

Tracer tests and contaminant transport rates in dual-porosity formations with application to the WIPP., 1998, Ostensen Raymond W.

A geomorphological strategy for conducting environmental impact assessments in karst areas, 1999, Veni G. ,
In their efforts to protect regional groundwater supplies, governmental agencies are increasingly requiring studies of karst areas and their features. In areas where tracer tests or geophysics are not required, funded, or otherwise feasible, geomorphological methods remain as the primary tool for assessing karst. This study proposes a geomorphologically-based environmental impact assessment strategy for karst areas. While it is supported with results from a study of the karstic Edwards Aquifer recharge zone on the Camp Bullis Military Training Installation, TX, USA, it is based on the study of several karst areas and is generalized to accommodate and be fine-tuned for regional variations. Biological and other resource issues can also be assessed with this strategy. The assessment identifies environmentally sensitive features and areas, as is often required to meet regulatory directives. In karst areas with relatively small features, excavation is a key tool for accurate assessment. Although the results of this study will help to better manage karst areas, proper management must be done on a regional scale. The highly permeable nature of karst precludes adequate management solely on a feature-by-feature basis. Studies on the relationship of water quality to impervious cover show adverse environmental impacts significantly increase when impervious cover exceeds 15% of a surface watershed. The Camp Bullis study finds similar impacts in its groundwater drainage basin, supporting the argument of 15% impervious cover as a regionally effective means of also protecting karst aquifers when coupled with protection of critical areas identified by field surveys.

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)

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