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Speleology in Kazakhstan

Shakalov on 04 Jul, 2018
Hello everyone!   I pleased to invite you to the official site of Central Asian Karstic-Speleological commission ("Kaspeko")   There, we regularly publish reports about our expeditions, articles and reports on speleotopics, lecture course for instructors, photos etc. ...

New publications on hypogene speleogenesis

Klimchouk on 26 Mar, 2012
Dear Colleagues, This is to draw your attention to several recent publications added to KarstBase, relevant to hypogenic karst/speleogenesis: Corrosion of limestone tablets in sulfidic ground-water: measurements and speleogenetic implications Galdenzi,

The deepest terrestrial animal

Klimchouk on 23 Feb, 2012
A recent publication of Spanish researchers describes the biology of Krubera Cave, including the deepest terrestrial animal ever found: Jordana, Rafael; Baquero, Enrique; Reboleira, Sofía and Sendra, Alberto. ...

Caves - landscapes without light

akop on 05 Feb, 2012
Exhibition dedicated to caves is taking place in the Vienna Natural History Museum   The exhibition at the Natural History Museum presents the surprising variety of caves and cave formations such as stalactites and various crystals. ...

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That rain intensity is the intensity of rain fall expressed in depth per time (in/hr) [16].?

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Chemistry and Karst, White, William B.
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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
Microbial mediation of complex subterranean mineral structures, Tirato, Nicola; Torriano, Stefano F.F;, Monteux, Sylvain; Sauro, Francesco; De Waele, Jo; Lavagna, Maria Luisa; D’Angeli, Ilenia Maria; Chailloux, Daniel; Renda, Michel; Eglinton, Timothy I.; Bontognali, Tomaso Renzo Rezio
Evidence of a plate-wide tectonic pressure pulse provided by extensometric monitoring in the Balkan Mountains (Bulgaria), Briestensky, Milos; Rowberry, Matt; Stemberk, Josef; Stefanov, Petar; Vozar, Jozef; Sebela, Stanka; Petro, Lubomir; Bella, Pavel; Gaal, Ludovit; Ormukov, Cholponbek;
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Your search for mean residence time (Keyword) returned 16 results for the whole karstbase:
Showing 1 to 15 of 16
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

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

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

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

Geochemistry of Carlsbad Cavern Pool Waters, Guadalupe Mountains, New Mexico, 2000, Forbes, J. R.
Water samples collected from 13 pools in Carlsbad Cavern were analyzed to determine the concentrations of major ions. Air temperature, relative humidity, and carbon dioxide concentration of the cave atmosphere were also measured. Large differences in water quality exist among different cave pools, with some pools containing very fresh water, while others are brackish, with total dissolved solids concentrations up to 5000 mg/L. Brackish water pools appear to be associated with those portions of the cave where evaporation rates are high and/or soluble minerals are present. Geochemical speciation modeling showed that some pools are close to saturation with respect to the common cave minerals aragonite, calcite, gypsum, and hydromagnesite. A tracer test was performed using a non-toxic bromide salt to estimate the leakage rates of selected pools. Pool volumes calculated based on dilution of the bromide tracer were up to 550 m. The tracer test results were used to calculate mean residence times for the water in each pool. Calculated mean residence times based on bromide tracer loss rates ranged from less than a year for Rookery Pool and Devils Spring to 16 years for Lake of the Clouds. Calculated pool leakage rates ranged from 2 L/day to over 100 L/day. The pools with the highest leakage rates appear to be Rookery Pool, Green Lake, and Lake of the Clouds. The long residence times indicated by the tracer tests suggest that the pools evaporate more water than they leak. However, evaporation should result in an accumulation of dissolved chloride and other solutes in the pools, which for most pools does not appear to be the case. Taken together, these observations suggest that the pools are recharged primarily by infrequent precipitation events, separated by long periods of slow evaporation and minimal leakage.

Controls on trace element (Sr-Mg) compositions of carbonate cave waters: implications for speleothem climatic records, 2000, Fairchild Ij, Borsato A, Tooth Af, Frisia S, Hawkesworth Cj, Huang Ym, Mcdermott F, Spiro B,
At two caves (Clamouse, S France and Ernesto, NE Italy), cave drip and pool waters were collected and sampled at intervals over a 2-3 year period. Mg/Ca and Sr/Ca concentration ratios, corrected for marine aerosols, are compared with those of bedrocks and, in some cases, aqueous leachates of soils and weathered bedrocks. Cave waters do not lie along mixing lines between calcite and dolomite of bedrock carbonate, but typically show enhanced and covarying Mg/Ca and Sr/Ca. Four factors are considered as controlling processes. (1) The much faster dissolution rate of calcite than dolomite allows for the possibility of increase of Mg/Ca if water-rock contact times are increased during drier conditions. A theoretical model is shown to be comparable to experimental leachates. (2) Prior calcite precipitation along a flow path is a powerful mechanism for generating enhanced and covarying Mg/Ca and Sr/Ca ratios. This mechanism requires the solution to lose CO, into pores or caverns. (3) Incongruent dolomite dissolution has only limited potential and is best regarded as two separate processes of dolomite dissolution and calcite precipitation. (4) selective leaching of Mg and Sr with respect to Ca is shown to be important in leachates from Ernesto where it appears to be a phenomenon of calcite dissolution. In general selective leaching can occur whenever Ca is sequestered into precipitates due to freezing or drying of soils, or if there is derivation of excess Sr and Mg from non-carbonate species. The Ernesto cave has abundant water supply which in the main chamber is derived from a reservoir with year-round constant P-CO2 of around 10(-2.4) and no evidence of calcite precipitation in the karst above the cave. Two distinct, bur overlying trends of enhanced and covarying Mg/Ca and Sr/Ca away from the locus of bedrock compositions are due to calcite precipitation within the cave and, at a variable drip site, due to enhanced selective leaching at slow drip rates. Mg-enhancement in the first chamber is due to a more dolomitic bedrock and longer residence times. The Clamouse site has a less abundant water supply and presents geochemical evidence of prior calcite precipitation. both in the cave and in overlying porous dolomite/dedolomitized limestone bedrock. Initial P-CO2 values as high as 10(-1) are inferred. Experimental incubations of Clamouse soils which generated enhanced P-CO2 and precipitated CaCO3 had compositions similar to the karst waters. Calcite precipitation is inferred to he enhanced in drier conditions. Hydrological controls on cave water chemistry imply that the trace element chemistry of speleothems may be interpretable in palaeohydrological terms. Drier conditions tends to promote not only longer mean residence times (enhancing dolomite dissolution and hence Mg/Ca), but also enhances degassing and calcite precipitation leading to increased Mg/Ca and Sr/Ca. (C) 2000 Elsevier Science B.V. All rights reserved

TRACER: An EXCEL Workbook to Calculate Mean Residence Time in Groundwater by Use of Tracers CFC-11, CFC-12 and Tritium, 2002, Bayari C. Serdar
An EXCEL workbook is presented for calculating the mean residence time of groundwater based on the environmental tracers, tritium, CFC-11 and CFC-12. The program TRACER is written in Visual Basic for Application language and uses piston, exponential, linear, exponential-piston and linear-piston flow types of lumped-parameter models. Input and output data are stored in worksheets and a graph of results that are best fitted to observations is drawn for visual evaluation. Recharge temperature and altitude are used to convert atmospheric partial pressures of CFC-11 and CFC-12 to dissolved concentrations to provide a direct comparison between the models' output and observed data. The model can also be used to check whether an inferred flow type could be valid in the groundwater system being investigated. Other radioactive and gaseous environmental tracers and reactions such as, sorption and degradation can be included either as decay constant or with modifications in the program code. TRACER matches, satisfactorily, the results obtained from other softwares.

LUMPED: a Visual Basic code of lumped-parameter models for mean residence time analyses of groundwater systems, 2003, Ozyurt N. Nur, Bayari C. Serdar
A Microsoft Visual Basic 6.0 (Microsoft Corporation, 1987?1998) code of 15 lumped-parameter models is presented for the analysis of mean residence time in aquifers. Groundwater flow systems obeying plug and exponential flow models and their combinations of parallel or serial connection can be simulated by these steady-state models which may include complications such as bypass flow and dead volume. Each model accepts tritium, krypton-85, chlorofluorocarbons (CFC-11, CFC-12 and CFC-113) and sulfur hexafluoride (SF6) as environmental tracer. Retardation of gas tracers in the unsaturated zone and their degradation in the flow system may also be accounted for. The executable code has been tested to run under Windows 95 or higher operating systems. The results of comparisons between other comparable codes are discussed and the limitations are indicated.

Investigation of the groundwater residence time distribution in the Aladag (Kayseri-Adana, Turkey) karstic aquifer. PhD Thesis, 2004, Ozyurt, N. Nur

The Aladað karstic aquifer of Eastern Taurids Range extends between 400m and 3750m elevations and, covers an area of 1900 km2 within Adana-Kayseri-Niðde provinces. The study covers the Kapuzbaþý, Göksu shallow circulation and Yerköprü 1, Yerköprü 2 and Yerköprü 3 deep circulation springs that extend from recharge area to the Zamanti river.
The system is fed by precipitation of Mediterranean origin and total precipitation input, evapo-transpiration, net recharge and its volumetric equivalent are found to be 1113 mm, 451 mm, 879 mm and 939 106 m3. Mean annual discharges of Yerköprü 3, Yerköprü 1 and 2, Göksu and, Kapuzbaþý and Barazama springs are 449 106 m3, 82 106 m3, 299 106 m3 and 146 106 m3. Noble gas ( 20Ne, 40Ar, 84Kr) and 18O isotopes suggest recharge area elevation and temperature ranges of 1700-2100m and 2-6 oC. The helium (He) content of groundwater increases with increasing circulation depth. Year round biweekly-monthly samples’ electrical conductivity, tritium ( 3H) and 18O content reveal that Kapuzbaþý and Göksu springs and, Yerköprü 1 and Yerköprü 2 springs behave similarly among themselves.
The “CFC model ages” of the springs where, chlorofluorocarbon (CFC) contents increased from 1997 to 2002, range between 10 to 20 years and 20 to 30 years in the shallow and deep circulation parts, respectively. The 3H/3He* absolute age of groundwater from springs is around 20 +/- 2.5 years. In the computer code LUMPEDUS that was developed for unsteady state lumped parameter modeling applications, 3H, tritiogenic helium-3 ( 3He*), CFC-11, CFC-12, CFC-113, and 18O were used as environmental tracers. Serially connected plug-exponential flow model applied to all springs. All models were calibrated for observed outflux and their forecasted 3H, 3He* and 18O time series were found to be in good agreement with the observations. Mean residence times found by models are in agreement with 3H/3He* ages. According to residence time distribution suggested by models, most of the discharges comprise recharges that occurred within last 20 to 30 years. Sixty per cent of discharge comprises recharges of the last 3 to 4 years. The active reservoir volumes of Yerköprü 1-2, Kapuzbaþý, Göksu and Yerköprü 3 springs are found to be 1604 106 m3, 2808 106 m3, 5728 106 m3 and 8609 106 m3 , respectively. According to well established linear relationship between reservoir volumes and discharge elevations, an active volume increases 50 106 m3 per 1m decrease in elevation. Cumulative active reservoir volume is found to be 18749 106 m3 at 450 m elevation where Yerköprü 3 spring is located. Uppermost elevation of active reservoir is located at 836m. Groundwater’s velocity ranges from 2.09 m/day to 5.57 m/day and the corresponding hydraulic conductivities for different reservoirs are between 41.8 m/day and 212.2 m/day. The ordering of hydraulic conductivity among springs ( > > > ) seems to be related to their time of formation. Based on an assumption of 1500m of maximum hydraulic head at the recharge area, the effective porosity of the system is estimated to be 0.86 per cent.


LUMPED Unsteady: a Visual Basic code of unsteady-state lumped-parameter models for mean residence time analyses of groundwater systems, 2005, Ozyurt N. Nur , Bayari C. Serdar
A Microsoft Visual Basic 6.0 (Microsoft Corporation, 1987?1998) code of 9 lumped-parameter models of unsteady flow is presented for the analysis of mean residence time in aquifers. Groundwater flow systems obeying plug and well-mixed flow models and their combinations in parallel or serial connection can be simulated by the code. Models can use tritium, tritiugenic He-3, oxygen-18, deuterium, krypton-85, chlorofluorocarbons (CFC-11, CFC-12 and CFC-113) and sulfur hexafluoride (SF6) as the environmental tracers. The executable code runs under all 32-bit Windows operating systems. Details of the code are explained and its limitations are indicated.

Sources and processes affecting sulfate in a karstic groundwater system of the Franconian Alb, southern Germany, 2005, Einsiedl F, Mayer B,
Chemical and isotope analyses on groundwater sulfate and H-3 measurements on groundwater were used to determine the sulfate sources and sulfur transformation processes in a heterogeneous karst aquifer of the Franconian Alb, southern Germany. Sulfate was found to be derived from atmospheric deposition. Young groundwater was characterized by high sulfate concentrations and delta(34)S values similar to those of recent atmospheric sulfate deposition. However,the delta(18)O values of groundwater SO42- were depleted by several per mil with respect to those of atmospheric deposition. This isotopic shift is indicative of mineralization of carbon-bonded S in the vadose zone of the karst system. In groundwater with mean residence times of more than 60 years, a trend of increasing delta(34)S values and 6180 values with decreasing sulfate concentrations was observed. This trend could not be solely explained by preindustrial atmospheric sulfate deposition with higher delta(34)S values, and hence, we conclude that bacterial (dissimilatory) sulfate reduction in the porous matrix of the karst aquifer must have occurred. This process has the potential to contribute to long-term biodegradation of contaminants in the porous rock matrix representing the dominant water reservoir of the fissured porous karst aquifer

Steady- and unsteady-state lumped parameter modelling of tritium and chlorofluorocarbons transport: hypothetical analyses and application to an alpine karst aquifer, 2005, Ozyurt N. N. , Bayari C. S. ,
Determination of a groundwater's mean residence time with the aid of environmental tracers is common in hydrogeology. Many of the lumped parameter (LP) applications used for this purpose have been based on steady-state models. However, the results may be misleading if a steady LP model is used to simulate the environmental tracer transport in an unsteady aquifer. To test this hypothesis, the results of steady and unsteady versions of several LP models were evaluated theoretically and in an alpine karst aquifer case by using tritium, oxygen-18 and chlorofluorocarbons (CFCs). The results reveal that the mean residence times obtained may be significantly different between the steady and unsteady versions of the same model. For the karst aquifer investigated, a serially connected exponential and a plug flow model were run under unsteady conditions. It is shown that outflux calibration with an unsteady model provides a firm basis in evaluating the results of models. An outflux-calibrated unsteady model predicted reasonably the observed series of water isotopes. The calibrated model's CFCs output overpredicts the observed concentrations, probably because of the time lag in the unsaturated zone of the alpine karst aquifer. Copyright (c) 2005 John Wiley & Sons, Ltd

Residence time distribution in the Kirkgoz karst springs (Antalya-Turkey) as a tool for contamination vulnerability assessment, 2007, Ozyurt N. Nur
Lumped parameter modeling of environmental tracer (tritium, CFCs and tritiogenic helium-3) transport in the Kirkgoz karst springs (Antalya-Turkey) appears to be a useful tool for assessing the vulnerability to contamination. Based on tritium observations between 1963 and 2000, the springs revealed a mean residence time (MRT) of 120 years. This suggests an active transport volume of 71 billion cubic meters for the aquifer, a value that is coherent with the estimated void volume of karst aquifer based on the mass of associated travertine deposits. The CFC-11 and CFC-12 MRTs are in agreement with tritium-based MRT, after correcting for excess air effect. Excess crustal and mantle helium flux hindered the use of tritiogenic helium-3 as a potential tracer. The residence time distribution (RTD) indicates a groundwater transport system that is fed by recharges extending back to past several hundred years. This wide RTD suggests that any recent contamination that may have entered the system could progress slowly within the entire aquifer but would be unnoticed in the early period because of the dilution effect of uncontaminated past recharge waters. Once the contamination is recognized, it may last for many centuries ahead even if the contamination practice is stopped. Thus, control of contaminant release to aquifer and monitoring of contaminant level in Kirkgoz springs is an immediate task for the associated public health authorities.

Isotopic and hydrochemical data as indicators of recharge areas, flow paths and waterrock interaction in the Caldas da RainhaQuinta das Janelas thermomineral carbonate rock aquif, 2013, Marques J. M. , Graa H. , Eggenkamp H. G. M. , Neves O. , Carreira P. M. , Matias M. J. , Mayer B. , Nunes D. , Trancoso V. N.

An updated conceptual circulation model for the Caldas da Rainha and Quinta das Janelas thermomineralwaters was developed. These thermomineral waters (T _ 33 _C) are related to a huge syncline ascribed tothe regional flow paths. Two diapiric structures were responsible for the uplift and subsequent folding ofregional Jurassic carbonate rocks. Environmental isotopic (d2H and d18O) data indicates that the mainrecharge area of the thermomineral system is linked to the Jurassic limestones (Candeeiros Mountains,E border of the syncline). The thermomineral waters belong to the Cl–Na sulphurous-type, with a totalmineralization of about 3000 mg/L. The thermomineral aquifer system seems to be ‘‘isolated’’ fromanthropogenic contamination, which is typical for the local shallow groundwater systems, due to theexistence of impermeable layers composed of a series of loamy and detritic rocks of the Upper Jurassic.The presence of 3H in some thermomineral borehole waters, not accompanied by an increase in SO2_4 andNO_3 , could be ascribed to different underground flow paths and different mean residence time. Thed34S(SO4) and d18O(SO4) values of dissolved sulphate of groundwaters of the Caldas da Rainha Spas indicatethat the sulphate is the result of water–rock interaction with evaporitic rocks (e.g. gypsum and anhydrite)ascribed to the regional synclinal structure.


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