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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. ...

Did you know?

That porosimeter is a device used to measure porosity [16].?

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Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
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Geochemical and mineralogical fingerprints to distinguish the exploited ferruginous mineralisations of Grotta della Monaca (Calabria, Italy), Dimuccio, L.A.; Rodrigues, N.; Larocca, F.; Pratas, J.; Amado, A.M.; Batista de Carvalho, L.A.
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
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Your search for residence time (Keyword) returned 70 results for the whole karstbase:
Showing 1 to 15 of 70
Significance and origin of very large regulating power of some karst aquifers in the Middle East. Implication on karst aquifer classification, , Elhakim M, Bakalowicz M,
SummaryKarst aquifers are the main groundwater resource in Lebanon as well as in most Mediterranean countries. Most of them are not exploited in a sustainable way, partly because their characteristics remain unknown. Karst aquifers are so complex that the assessment of their resource and their exploitable storage requires an analysis of their whole functioning, particularly by analysing the spring hydrograph. Among all various methods, the method proposed by Mangin aims to characterize at the same time the recharge conditions and the storage and recession of the saturated zone by analyzing the spring hydrograph. This method defines two parameters, the infiltration delay i, and the regulating power k which are the roots of a classification of karst systems. This classification makes the distinction between karst and porous aquifers considering the value of the regulating power. k is assumed to be lower than 0.5 in karst, and between 0.5 and 1 for all other aquifers, 1 being the upper limit.The study of karst aquifers in Lebanon shows values of k > 0.5, and even 1; former data from the literature show that other karst springs in Middle East have comparable characteristics. In fact, what is not considered by Mangin and others, k is equivalent to a mean residence time in years of water in the saturated zone. So long residence times are normally observed in poorly karstified aquifers, or containing abandoned, not functioning karstification. The geological framework in which the studied springs are located in fact shows that these aquifers have been subject to a long, complex evolution, as a consequence of the base level rising. This rising produced the flooding of the successive karst drainage network, which does not really function anymore and provides a large storage capacity to the aquifer. The very interesting properties of these aquifers make them prime targets for fulfilling the increasing needs of water

Laboratory and field evidence for a vadose origin of foibe (domepits)., 1965, Reams Max W.
Foiba (plural, foibe) is a term derived from the northeastern Italian karst region. The word is here suggested for use in preference to other terms referring to vertical cavities in soluble rocks. Foiba is defined as a cavity in relatively soluble rock which is natural, solutional, tends toward a cylindrical shape, and possesses walls which normally approach verticality. In laboratory experiments, limestone blocks were treated with dilute hydrochloric acid, and cavities resembling foibe were produced. Vertical walls developed only when a less soluble layer capped the limestone block or when the acid source was stationary, allowing acid to drip to the area directly below. Water analyses from foibe in central Kentucky and Missouri indicate that the water has had less residence time in the zone of aeration than other waters percolating through the rocks and entering the caves. In central Kentucky, foibe seem to be developed by migrating underground waterfalls held up by less soluble layers or by water moving directly down joints below less soluble layers. In Missouri, foibe are formed by joint enlargement below chert layers. Those foibe in the ceilings of caves are complicated by the enlargement of the lower part of the joints by cave streams during fluctuating water table conditions. In limestone caves of Kansas, foibe are formed in a similar manner as in Missouri. The foibe of the gypsum caves of Kansas are formed mainly on the sides of steep collapse sinkholes and lack joint control although they form beneath less soluble layers in the gypsum. Dripping water is necessary for the development of vertical walls by solution. Less soluble layers seem to be the unique feature which allows water to drip and pour into foibe. The floors of foibe are formed by less soluble layers or near the water table. If foibe intersect previously formed cave passages, no floors may develop.

A Chemical Investigation of some Groundwater of the Northern Limestone at Jenolan Caves, 1977, James Julia M. , Handel M. L.

A brief description of the geology and drainage of the Northern limestone at Jenolan Caves is introduced. Approaches to karst geochemistry are given. The reasons are given for the choice of complete chemical analyses followed by calculations of the thermochemical parameters (saturation indices with respect to calcite and dolomite, SIc and SId, and the partial pressure of carbon dioxide PCO2) for the Jenolan groundwaters. The methods of chemical analysis and thermochemical calculations are reported. The results of the groundwater survey are presented both as the raw chemical data and the derived thermochemical data. The raw data give more useful information than the calculated parameters. The results obtained by this survey are consistent with observations and the previous knowledge of the underground drainage of the Northern limestone. The water chemistry reflected the rock type and the residence time of the water in bedrock and gravels. It is concluded that the Jenolan underground River and Central River have different types of source and that Central River is not a braid of the Jenolan Underground River.


Surface Lowering and Landform Evolution on Aldabra, 1979, Trudgill S. T. ,
Aldabra landforms are the result of the karstification of carbonate rocks distributed on surfaces which have been exposed to erosion for varying lengths of time. Morphometric analysis (which is of interest in both geomorphological and botanical contexts) suggests that the most well developed karst features (closed depressions) occur on what appear to be the oldest surfaces. Morphology also varies with lithology. Measurements of present-day erosion rates suggests that weakly cemented rocks and the most soluble mineral components are eroding most rapidly. The evolution of a dissected morphology is related to lithological heterogeneity in coralline rocks or, in the case of the more homogeneous rocks, to the short residence time of waters on the rock surface (the more rapidly dissolving mineral grains eroding faster). Dissolution also proceeds in fresh water pools, but this may be offset by precipitation in some cases. The surface is mostly case hardened, except under deep organic soils where erosion rates are much higher than in other areas. A mean erosion rate measured at 0.26 mm/a appears to make it feasible that large erosional features, such as the lagoon, could have been formed during periods of emersion as suggested by research workers who have hypothesized that an atoll shape may be substantially derived by subaerial weathering

A reconnaissance isotope study of waters in the karst of the Western Tatra mountains, 1988, Rozanski K. , Dulinski M. ,
Presented are results of isotope investigations of waters collected in the karstic area of the Western Tatra Mts. Altogether 35 groundwater samples have been analysed (tritium content, [delta]D, [delta]18O). They represent groundwaters collected on the earth surface (springs, streams, exurgences) as well as waters found in caves. Parallel, systematic isotope analyses of monthly precipitation collected at the Ornak station located in the center of the investigated area were also carried out. The results of isotope investigations fully confirm earlier suggestions that the karst system of the Western Tatra Mts consists of separate independent subsystems exhibiting weak (if any) hydraulic interconnections. Tritium data allow a semi-quantitative assessment of the mean residence time of the baseflow component in the investigated system. It is equal to at least 7/8 years. Eventual further measurements of tritium content should allow a more precise determination of this parameter. [delta]D and [delta]18O analyses of the investigated waters provide a basis for assessment of the Is/I ratio i.e. the ratio of infiltration originating from summer precipitation to the total yearly infiltration. It appears that groundwaters collected in caves exhibit on the average significantly higher D and 18O content compared to groundwaters collected on the surface. Possible reasons of this effect are discussed thoroughly in the paper

COMPARISON OF THE C-14 ACTIVITY OF GROUNDWATER AND RECENT TUFA FROM KARST AREAS IN YUGOSLAVIA AND CZECHOSLOVAKIA, 1989, Horvatincic N. , Srdoc D. , Silar J. , Tvrdikova H. ,
C-14 activity of dissolved inorganic carbon (DIC) in water and in recent tufa samples in several karst areas of Yugoslavia and Czechoslovakia was measured. Groundwater from 11 karst springs were measured for their isotopic content (C-14, H-3, C-13), chemical composition (HCO3, Ca2, Mg2) and physico-chemical properties (temperature, pH). Seasonal variations of the C-14 activity of DIC in two karst springs in Plitvice Lakes area, Yugoslavia, were measured systematically from 1979-1987. C-14 activity of recent tufa samples from several locations downstream were also measured. The activity of DIC in karst spring water in both countries ranged from 63-87 pMC, which is attributed to differences in geologic structure of the recharge area, topsoil thickness and composition. Grouping of C-14 activities of DIC ca (824)% is evident. Tritium activity at all the springs indicated short mean residence time (1-10 yr). Concentration of HCO3, Ca2 and Mg2 in spring water varied with geomorphology. C-14 activity of streamwater and recent tufa increased downstream from karst springs due to the exchange between atmospheric CO2 and DIC

Periglacial waters within the Muschelkalk aquifer in southern Poland. [in Polish], 1993, R?kowski, Andrzej

Radiocarbon concentration and origin of thermal Karst waters in the region of the Bukk Mountains, northeastern Hungary, 1995, Hertelendi E. , Veres M. , Futo I. , Svingor E. , Miko L. , Lenart L. , Deak J. , Suveges M. ,
Karst springs are abundant in Hungary, and many are thermal (temperatures >30 degrees C). As thermal springs are a significant part of Hungary's water resources, it is important to quantify their travel times in the karst systems. Thus, we chose to measure T and delta(18)O in the water and delta(13)C and C-14 in dissolved inorganic carbon (DIC) in water from 50 thermal and nonthermal springs and wells in the Bukk Mountains, northeastern Hungary, Environmental isotope data confirm the karst waterflow pattern implied by earlier studies. We found the water in warm springs and boreholes to be mixtures of cold young and old thermal water. We also determined short mean-residence times for some large cold springs. The C-14 activities measured in these springs indicate that the recharge area of the karst aquifer is open to the atmosphere, and atmospheric CO2 contributes to the C-14 activity of these groundwaters. We observed good correlation between C-14 and H-3 activities and we determined negative correlations between C-14 concentration and delta(13)C values and temperature. From the delta(18)O values of the oldest thermal waters, we attribute their origin to precipitation during colder temperatures than at present

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.

Elevated and variable values of 13C in speleothems in a British cave system, 1997, Baker A, Ito E, Smart Pl, Mcewan Rf,
[delta] 13C isotope variations in speleothems have been investigated for samples from the British Isles, where plants which use the Hatch-Slack or C4 photosynthetic pathway are not present. The range of [delta] 13C expected in speleothem carbonate formed in isotopic equilibrium with soil CO2 derived from the overlying C3 vegetation should thus fall in the range -12 to -6[per mille sign]. Forty-one actively growing speleothem samples from low-discharge sites were analysed from Stump Cross Caverns, Yorkshire, England. Ten percent have [delta] 13C greater than -6%. In addition, a large range of [delta] 13C was observed (-8.06 1.38[per mille sign], a 1 [sigma] variability of 17%), with adjacent samples having [delta] 13C differing by a maximum of 4.74[per mille sign]. Similar findings were obtained from a review of analyses of late Quaternary speleothem samples from the British Isles, with 75% of flowstone samples and 57% of high-flow stalagmite samples exhibiting elevated [delta] 13C. Three possible processes are proposed as possible causes of elevated [delta] 13C in speleothems. Firstly, fractionation may occur between the stalactite and stalagmite due to evaporation or degassing. Secondly, degassing of the groundwaters may have occurred within the aquifer before reaching the cave void, allowing release of some CO2 from the water whilst remaining saturated in calcium. Finally, the elevated [delta] 13C may be due to short water residence times in the soil, such that equilibrium between soil water and soil CO2 is not reached. Evidence presented here demonstrates that any one of these mechanisms may be important in the karst areas of the British Isles. Caution is needed before interpreting the [delta] 13C signal within speleothems in terms of palaeovegetation

Risk assessment methodology for karst aquifers .1. Estimating karst conduit-flow parameters, 1997, Field Ms, Nash Sg,
Quantitative ground-water tracing of conduit-dominated karst aquifers allows for reliable and practical interpretation of karst ground-water flow. Insights into the hydraulic geometry of the karst aquifer may be acquired that otherwise could not be obtained by such conventional methods as potentiometric-surface mapping and aquifer testing. Contamination of karst aquifers requires that a comprehensive tracer budget be performed so that karst conduit hydraulic-flow and geometric parameters be obtained. Acquisition of these parameters is necessary for estimating contaminant fate-and-transport. A FORTRAN computer program for estimating total tracer recovery from tracer-breakthrough curves is proposed as a standard method. Estimated hydraulic-flow parameters include mean residence time, mean flow velocity, longitudinal dispersivity, Peclet number, Reynolds number, and Froude number. Estimated geometric parameters include karst conduit sinuous distance, conduit volume, cross-sectional area, diameter, and hydraulic depth. These parameters may be used to (1) develop structural models of the aquifer, (2) improve aquifer resource management, (3) improve ground-water monitoring systems design, (4) improve aquifer remediation, and (5) assess contaminant fate-and-transport. A companion paper demonstrates the use of these hydraulic-flow and geometric parameters in a surface-water model for estimating contaminant fate-and-transport in a karst conduit. Two ground-water tracing studies demonstrate the utility of this program for reliable estimation of necessary karst conduit hydraulic-flow and geometric parameters

Environmental isotope study of the major karst springs in Damascus limestone aquifer systems: Case of the Figeh and Barada springs, 1997, Kattan Z. ,
The groundwaters of major karst springs and several piezometers and wells in the Damascus limestone aquifer systems (Syria) have been investigated using chemical and environmental isotope techniques. The groundwater bodies of major karat springs mainly originate from direct infiltration of atmospheric water. The groundwaters emerging from the Figeh main spring have lower stable isotope concentrations than those emerging from the Barada spring. Stable isotopes show that the elevation of the recharge zones of the Figeh main spring (1750 m above sea level) is higher than those for the Figeh side spring (1500 m) and the Harouch spring (1300 m). The groundwater in the Barada spring seems to be recharged in a catchment area with a mean elevation of about 1250 m. The temporal evolution of stable isotope concentrations, tritium content and hydrochemistry show the existence of an interconnection between the aquifers of the Figeh main spring and the Figeh side spring, especially during flood periods. The distinct independent isotopic composition of Harouch spring from those of Figeh main and side springs suggests no interconnection with the Figeh aquifers. Adopting a model with exponential time distribution, the mean turnover time (residence time) of groundwater in Figeh main spring was evaluated to be 50 years. On the basis of this evaluation, a value of about 3.9 billion m(3) was obtained for the maximum groundwater reservoir size. (C) 1997 Elsevier Science B.V

Spatial and Temporal Variations in the Dissolved Organic Carbon Concentrations in the Vadose Karst Waters of Marengo Cave, Indiana, 1998, Toth, V. A.
In order to better understand the organic content of microbands in speleothems, seasonal variations in the organic concentrations of vadose drip waters were examined in relation to climatic and environmental variables. Seasonal variations in the organic concentrations of the vadose waters were observed by documenting the fluctuations of Dissolved Organic Carbon (DOC) and its corresponding fluorescence. Tracer dye tests established that the larger drips depositing calcite in Marengo Cave were fed by waters with a short residence time. A strong seasonal variation in DOC concentrations and natural fluorescence was detected at quickly responding sites. Slow, constant drip sites displayed a weaker seasonality. Further investigation is required to distinguish low fluorescing DOC and to determine if the same fluorophors identified in the vadose water can be identified in the organics trapped in the recipient calcite. The overall conclusions are that fluorescence is well correlated with DOC when the fluorescence range is high but it is not a strong indicator of DOC at low fluorescence values; that the value of fluorescence as a predictor of DOC may vary significantly with individual sampling sites; and that the highest fluorescence values occur in springtime and the weakest in summer and fall.

Estimating subsurface fissure apertures in karst aquifers from equilibrium activities, 1998, Field Ms, Mose Dg,
Rn-222 activities were determined for the karst aquifer underlying Walkersville, Maryland, in an area of ground-water discharge from a single geological unit during the summer and fall seasons, Radon-222 equilibrium activities in karst ground waters can be employed in mass-balance models to estimate microfissure, macrofissure, and conduit aperture dimensions, This approach defines Rn-222 generation and loss in karst aquifers as a function of fissure apertures and the U-238 content of the rock, High Rn-222 activities occur in tight fissures and low Rn-222 activities occur in conduits, In the vadose zone, Rn-222 activities are low as a result of degassing, especially if flow is turbulent and activities are decoupled from the phreatic zone, In the phreatic zone, if recharge to fissures causes a reduction of residence time below that required for equilibrium (approximate to 26 days), Rn-222 activities fall, At springs and in the vadose zone, after a rainfall event, Rn-222 activities increase as waters with long residence and with high Rn-222 activities are expelled from fissure and fracture storage, Field data and selected literature values were used to test the model, Models used to predict median microfissure apertures for this karst aquifer yield aperture estimates ranging from 2.8 mu m to 9.2 mu m. Median macrofissure apertures ranged from 5.53 cm to 5.88 cm, Median conduit apertures ranged from 1.16 m to 1.24 m, Comparison of the models results with published data on karst aquifers and observations at the field site suggest that the predicted apertures are reasonable

Precipitation and dissolution of reactive solutes in fractures, 1998, Dijk P. , Berkowit B.

The precipitation and dissolution of reactive solutes, transported under the action of fully developed laminar flow in saturated fractures, is analyzed assuming an irreversible first-order kinetic surface reaction for one component. Equations describing solute transport, precipitation and dissolution, and the evolution of fracture aperture were approximated and solved using combined analytical and numerical techniques; dimensionless transport parameters incorporated into the solutions were estimated from data available in the literature. Fractures with initially flat, linearly constricted, and sinusoidal apertures were investigated. The initial fracture geometry and the solute saturation content of the inflowing fluid have a profound effect on the reaction processes. The results show that the evolution of the solute transport and fracture geometry can be adequately described by the Damköhler and Péclet numbers. Two extreme transport regimes were identified: relatively uniform evolution of fracture apertures and nonuniform evolution of fracture apertures restricted to the inlet region of fractures. In the case of precipitation with half-life times of the order of seconds to years and with fluid residence times of the order of minutes to days, the time for a fracture to close completely is of the order of days to millions of years. This is consistent with the order of magnitude of hydrogeological timescales. In the model the process of dissolution is the inverse of precipitation, although the combined solute transport and reaction processes are irreversible. These results and the applied dimensionless analysis can be used as a basis for the development of more complex models of reactive solute transport, precipitation, and dissolution in saturated fractured media.


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