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 dispersion, longitudinal is process whereby some of the water molecules and solute molecules travel more rapidly than the average linear velocity and some travel more slowly which results in spreading of the solute in the direction of the bulk flow [22].?

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 tracer (Keyword) returned 274 results for the whole karstbase:
Showing 16 to 30 of 274
APPLICATION OF MICROBIAL TRACERS IN GROUNDWATER STUDIES, 1991, Hotzl H. , Kass W. , Reichert B. ,
In situ tracing experiments have proved to be reliable tools to get direct information on subsurface flow direction and flow parameters. Beside dyes, salts, radioisotopes and drift bodies, microbes can be used as tracers. In several comparative experiments carried out in porous and karst aquifers by the International Association of Tracer Hydrology (ATH) the microbial markers (bacteria and bacteriophages) have shown promising results. They are especially suitable to explain and model the subsurface transport of microorganisms

WATER-BUDGET, FUNCTIONING AND PROTECTION OF THE FONTAINE-DE-VAUCLUSE KARST SYSTEM (SOUTHEASTERN FRANCE), 1992, Blavoux B, Mudry J, Puig Jm,
The karst aquifer of the well-known Fontaine de Vaucluse has been recently studied, results have been got about delimitation of the system and its working. Geological data (lithology and structure) have allowed to delimit an 1115 Km2 intake area including Ventoux-Lure north facing range (1,909-1,826 m) and the Plateau which is prolonging it southwards (Fig. 1 and 2). The average altitude of the whole area, obtained by balancing elevation belt surfaces, is about 870 m. This elevation squares with results of tracing tests (Fig. 3), environmental physical, chemical and isotopic tracings, that allow to value a 850 m average altitude for the intake area (Fig. 4). The moisture balance has been computed from an altitude belts climatic model, using local rain an temperature gradients (Fig. 5 and Table II), because the weather network is not representative. So, rainfalls rise of about 55 mm per 100 m elevation and temperature decreases of about 0.5-degrees-C per 100 m. The consequence of these two antagonist phenomena is the quasi constant value of actual evapotranspiration on each altitude belt. With the Fig. 7 organigram, curves of effective rainfalls and infiltration coefficient versus elevation can be plotted (Fig. 6). This computation shows that 3/4 of the total and the whole of dry season effective rainfalls are provided by the part of the intake area situated above the average altitude: on the lowest belt, effective rainfalls are only 120 mm per year and increase to 1380 mm on the upper section (Fig. 8 and Table 1). The weighted effective rainfalls are about 570 mm per year for the whole intake area. Hydrodynamical and physico-chemical studies show, despite its large size, the weak inertia of the system, so proves its good karstification, that confirms for the whole system the pin-point speleological observations. The discharge of the spring, which average value is 21 m3.s-1 (only 18 for the last ten years), can exceed 100 m3.s-1 and the minimum has never been lower than 3.7 m3.s-1 (Fig. 9). When it rains on the intake area, the increase of the discharge is very sudden in a rainy period : one to four days. This short delay is due to seepage through epikarst and unsaturated zone. During dry periods, the spring reaction is deadened, due to storage in the unsaturated zone. The silica content distribution was plotted during several hydrokinematical phases (Fig. 10). It shows: an almost unimodal distribution for the 8 km2 fissured limestone aquifer of Groseau; a multimodal one for the 1115 km2 karst aquifer of Fontaine de Vaucluse. This proves that karstification is more important than size in the response of the system. Weak summer rainfalls do not influence the discharge, nevertheless they influence chemistry of the spring water, and so interrupts the water depletion phasis. Then, the decrease of discharge can continue after the end of the chemical depletion phasis, water which is overflowing after summer rainfalls (in a dry period) is influenced hy the chemistry of seepage water : on the graph of a principal components analysis, done on chemical variables. an hysteresis phenomenon can be seen (Fig. 11). A discriminant analysis (Fig. 12) confirms that these autumn waters, with high ratio seepage tracers, are not reserve waters from the saturated zone. The ratio of reserve water in the total discharge, is preponderant: 3/4 and 2/3 respectively of the yearly runoff volumes for 1981 and 1982 (Fig. 13), but an important part of these reserves can be stored in the unsaturated zone. This storage capacity can be valued by different means: transposing to Vaucluse (1115 km2) the volume measured on another karst system in the Pyrenees (13 km2); it gives about 100 million m2; using setting parameters of Bezes model (1976) on the same aquifer: it gives 113 million m3; using depletion curves, that show, for instance during the 1989 summer and autumn dry period, a 80 million m3 volume. In all cases, we get a value of about one hundred million m3 for the storage capacity of the unsaturated zone. With a 20 m range of fluctuation for the water table and with a 10(-2) specific yield, on a 500 to 1,000 km2 saturated zone, the zone of fluctuation can release about 10 to 20 million m3. Then, the volume of water stored in the whole saturated zone, with a 300 m minimum thickness (depth of the waterlogged pit of the Fontaine), a 500 km2 minimum surface and a 10(-3) specific yield, is about 150 million m3, including 27 million m3 stored in the channels. So, the unsaturated zone represents a significant part of the whole storage capacity and most of the yearly renewable reserves. Paradoxically, the biggest french spring is not tapped at all; as its intake area is neither a regional nor a national park, no general protection covers it : because of its good karstification, the vulnerability of the system is important. Good quality of water is attributable to the low population and human activities density on the intake area (4 inh.km-2). A great part of the intake area is uncultivated (large forest and ''garrigues'' areas). Due to the lack of surface water and scantness of soils, agriculture is not intensive (lavender, thyme, sage and bulk wheat fields. meadowlands). On the mountainous zone, roads are salted in winter and snowmelt water can reach a significantly high chloride ratio than in a natural climatic functioning (for instance 25 mg.l-1 in Font d'Angiou where the ratio would have been 3 mg.l-1). As tourism is developing both on the mountain and on the plateau, the management of the highest intake area must be carefully held: its part is preponderant in the feeding of the system

ISOTOPE HYDROLOGICAL STUDY OF MEAN TRANSIT TIMES IN AN ALPINE BASIN (WIMBACHTAL, GERMANY), 1992, Maloszewski P. , Rauert W. , Trimborn P. , Herrmann A. , Rau R. ,
Measurements of tritium and O-18 concentrations in precipitation and runoff were used to provide further insight into the groundwater storage properties of the Wimbachtal Valley, a catchment area of 33.4 km2, extending between 636 and 2713 m a.s.l. in the Berchtesgaden Alps. The catchment includes three aquifer types: a dominant porous aquifer; a fractured dolomite; a karstic limestone aquifer. Employing a simple hydrological model, information about mean transit times of environmental tracers is derived for the groundwater runoff component and several karst springs from the application of the exponential and dispersion flow models to the isotopic input and output data. The mean transit times calculated from a dispersion model with transit times of 4.1 years for O-18 and 4.2 years for tritium, which agree well, allow calculation of total (mobile stagnant) groundwater storage volume, which is equivalent to 6.6 m of water depth. Direct runoff appears negligible as in many other cases

Tracer study and storage in the unsaturated zone of a karstic limestone aquifer, 1992, Bottrell S. H. , Atkinson T. C.

Tracer Hydrology, 1992, Hotzl H. , Werner A.

ESTIMATION OF PREFERENTIAL MOVEMENT OF BROMIDE TRACER UNDER FIELD CONDITIONS, 1994, Jabro J. D. , Lotse E. G. , Fritton D. D. , Baker D. E. ,
Leaching of agricultural chemicals from the root and vadose zones into groundwater is an important environmental concern. To procure a better understanding of the movement and transport of agricultural chemicals through the soil profile, a field research study was conducted to estimate bromide leaching losses under saturated conditions where preferential flow is occurring. The field data were then used to evaluate the LEACHM model. Eighteen double-ring infiltrometers were used to apply a pulse (100 mm depth) of bromide tracer on two previously saturated soils located in a karst region of southeastern Pennsylvania. Internal drainage over the next seven days resulted in nearly 51 % of the applied Br- being leached to a depth below 0.80 m. The LEACHM model was used to simulate the amount of bromide leached in each infiltrometer. The model predicted, accurately, an average of 46% of the applied Br- leached below the 0.80 m depth. Mcan values of bromide concentration in the soil profile were predicted within two standard deviations of the measured mean for all depths except for the 0.20-0.40 m depth increment where the model overpredicted the bromide concentration. The model predictions of Br- leached were tested against field measurements using several statistical tests. The LEACHM model performed adequately under preferential flow conditions, perhaps because the infiltration rate at each site was used as a model input. This, actually, is some measure of the macropore flow process and suggests that simple models such as LEACHM can be used in the field, as long as a distribution of infiltration rates is used as an input

An assessment of the potential adverse properties of fluorescent tracer dyes used for groundwater tracing., 1995, Field M. S. , Wilhelm R. G. , Quinlan J. F. , Aley T. J.

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)

CHEMICAL EVOLUTION OF GROUNDWATER NEAR A SINKHOLE LAKE, NORTHERN FLORIDA .1. FLOW PATTERNS, AGE OF GROUNDWATER, AND INFLUENCE OF LAKE WATER LEAKAGE, 1995, Katz B. G. , Lee T. M. , Plummer L. N. , Busenberg E. ,
Leakage from sinkhole lakes significantly influences recharge to the Upper Floridan aquifer in poorly confined sediments in northern Florida. Environmental isotopes (oxygen 18, deuterium, and tritium), chlorofluorocarbons (CFCs: CFC-11, CCl3F; CFC-12, CCl2F2; and CFC-113, C2Cl3F3), and solute tracers were used to investigate groundwater flow patterns near Lake Barco, a seepage lake in a mantled karst setting in northern Florida. Stable isotope data indicated that the groundwater downgradient from the lake contained 11-67% lake water leakage, with a limit of detection of lake water in groundwater of 4.3%. The mixing fractions of lake water leakage, which passed through organic-rich sediments in the lake bottom, were directly proportional to the observed methane concentrations and increased with depth in the groundwater flow system. In aerobic groundwater upgradient from Lake Barco, CFC-modeled recharge dates ranged from 1987 near the water table to the mid 1970s for water collected at a depth of 30 m below the water table. CFC-modeled recharge dates (based on CFC-12) for anaerobic groundwater downgradient from the lake ranged from the late 1950s to the mid 1970s and were consistent with tritium data. CFC-modeled recharge dates based on CFC-11 indicated preferential microbial degradation in anoxic waters. Vertical hydraulic conductivities, calculated using CFC-12 modeled recharge dates and Darcy's law, were 0.17, 0.033, and 0.019 mid for the surficial aquifer, intermediate confining unit, and lake sediments, respectively. These conductivities agreed closely with those used in the calibration of a three-dimensional groundwater flow model for transient and steady state flow conditions

Combined use of environmental isotopic and hydrochemical data in differentiation of groundwater flow patterns through the Aladağ karstic aquifer-Turkey, Application of Tracers in Arid zone Hydro, 1995, Bayari C. S. , Gunay G.
Distinction between the different groundwater flow systems in karstic areas constitutes one of the major objetives of the basin-wide hydrogeologic research. Use of environmental isotopic and hydrochemical investigation techniques provide a great deal of information for the identification of regional groundwater flow systems. The Lower Zamantı Basin, located in the eastern Taurids, presents an accountable water resource potential that can be used for hydroelectric power production. The basin, with the elevation range between 400 m and 350 m, occupies a catchment area of 2000 km2. Humid and semi-arid climatic regimes prevail in the southern and northern parts of the basin. The carbonate rocks and the overlaying impervious ophiolite nappe constitute the major geologic units in the area. Systematic hydrochemical and environmental isotopic surveys have been carried out to discriminate between the different groundwater flow systems existing in the basin. Hydrochemical studies have been conducted by insitu measurements, sampling and analyses of water samples from about 80 points. Based on the results of hydrochemical evaluations, 23 sampling points, including streams and karstic springs, have been selected for environmental isotopic survey. The integrated evaluation of the available data indicates clearly that two different groundwater flow patterns exist in the basin; namely a shallow flow and a deep regional flow. The characteristic values of temperature, electrical conductivity, carbonate alkalinity and log PCO2 of the shallow-flow in the karstic effluents fed by shallow groundwater circulation springs are 8C, 80 S/cm, 1.5 meq/l and 10-2 atm, respectively. On the other hand, higher values, such as 15C, 455 S/cm, 5.0 meq/l and 10-1 atm are observed in the springs fed by deep-regional groundwater flow. The tritium data indicate that the springs fed by the deep-regional groundwater have longer residence times. Moreover, the recharge area elevations, as envisaged from the oxygen-18 data, also provide supporting evidence for the distinction of different groundwater flow patterns. Additionally, comparison of groundwater temperature with oxygen-18 content presents reliable information to understand the possible interaction among the different karstic effluents.

Tracer Tehnologies for Hydrogeological Systems., 1995,

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.

Numerical multisource and multiscale imagery in the study of the topographic surface. Hydrogeological application in a karstic environment: Verneuil-sur-Avre (Perche, France), 1996, Sykioti O. , Deffontaines B. , Chorowicz J. , Obert D. , Demarsily G. , Lauverjat J. , Carvalho J. ,
We propose a new method revealing geological structures and their possible relationships with water percolation. It is based on a combination of (1) numerical analysis of the topography (satellite imagery Landsat TM, HCMM, SAR-ERS1; digital elevation model and derived data: drainage network, slope map, summit level surfaces...); (2) classic geological approach (field work, geological mapping, gravimetry); and (3) hydrogeological approach (piezometric map, tracer experiments). The superimposition of these data into a geocoded data base leads to the identification and the location of morphostructures (synthetic structural map). Field data and tracer experiments confirm the validity of the results. We propose to take into consideration the present day stress regime in order to define main orientations of open fractures. In conclusion, this method provides structural information allowing a better understanding of geometry in karstic aquifers

The combined use of Sr-87/Sr-86 and carbon and water isotopes to study the hydrochemical interaction between groundwater and lakewater in mantled karst, 1996, Katz B. G. , Bullen T. D. ,
The hydrochemical interaction between groundwater and lakewater influences the composition of water that percolates downward from the surficial aquifer system through the underlying intermediate confining unit and recharges the Upper Floridan aquifer along highlands in Florida. The Sr-87/Sr-86 ratio along with the stable isotopes, D, O-18, and C-13 were used as tracers to study the interaction between groundwater, lakewater, and aquifer minerals near Lake Barco, a seepage lake in the mantled karst terrane of northern Florida. Upgradient from the lake, the Sr-87/Sr-86 ratio of groundwater decreases with depth (mean values of 0.71004, 0.70890, and 0.70852 for water from the surficial aquifer system, intermediate confining unit, and Upper Floridan aquifer, respectively), resulting from the interaction of dilute oxygenated recharge water with aquifer minerals that are less radiogenic with depth. The concentrations of Sr2 generally increase with depth, and higher concentrations of Sr2 in water from the Upper Floridan aquifer (20-35 mu g/L), relative to water from the surficial aquifer system and the intermediate confining unit, result from the dissolution of Sr-bearing calcite and dolomite in the Eocene limestone. Dissolution of calcite [delta(13)C = -1.6 permil (parts per thousand)] is also indicated by an enriched delta(13)C(DIC) (-8.8 to -11.4 parts per thousand) in water from the Upper Floridan aquifer, relative to the overlying hydrogeologic units (delta(13)C(DIC) < -16 parts per thousand). Groundwater downgradient from Lake Barco was enriched in O-18 and D relative to groundwater upgradient from the lake, indicating mixing of lakewater leakage and groundwater. Downgradient from the lake, the Sr-87/Sr-86 ratio of groundwater and aquifer material become less radiogenic and the Sr2 concentrations generally increase with depth. However, Sr2 concentrations are substantially less than in upgradient groundwaters at similar depths. The lower Sr2 concentrations result from the influence of anoxic lakewater leakage on the mobility of Sr2 from clays. Based on results from mass-balance modeling, it is probable that cation exchange plays the dominant role in controlling the Sr-87/Sr-86 ratio of groundwater, both upgradient and downgradient from Lake Barco. Even though groundwater from the three distinct hydrogeologic units displays considerable variability in Sr concentration and isotopic composition, the dominant processes associated with the mixing of lakewater leakage with groundwater, as well as the effects of mineral-water interaction, can be ascertained by integrating the use of stable and radiogenic isotopic measurements of groundwater, lakewater, and aquifer minerals

Results 16 to 30 of 274
You probably didn't submit anything to search for