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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. ...

Did you know?

That allogenic valley is a karst valley incised by a watercourse originating on impervious rock with a volume sufficient for it to traverse a limestone area on the surface. the valley is incised from the limestone contact and with the passage of time the river is increasingly likely to pass underground as the waters enlarge joints. occasionally such a valley may represent the large-scale collapse of the cavern system along a subterranean stream or the enlarging of a series of karst windows [19].?

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Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
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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;
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Your search for oxygen-18 (Keyword) returned 10 results for the whole karstbase:
Results of measurements of the content of deuterium, oxygen-18 and tritium in water samples from test area taken during 1972-1975, 1976, Moser H. , Rajner V. , Rank D. , Stichler W.

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.

Interactions between ground water and surface water in the Suwannee River Basin, Florida, 1997, Katz B. G. , Dehan R. S. , Hirten J. J. , Catches J. S. ,
Ground water and surface water constitute a single dynamic system in most parts of the Suwannee River basin due to the presence of karst features that facilitate the interaction between the surface and subsurface. Low radon-222 concentrations (below background levels) and enriched amounts of oxygen-18 and deuterium in ground water indicate mixing with surface water in parts of the basin. Comparison of surface water and regional ground water flow patterns indicate that boundaries for ground water basins typically do not coincide with surface water drainage subbasins. There are several areas in the basin where around water flow that originates outside of the Suwannee River basin crosses surface water basin boundaries during both low-flow and high-flow conditions. In a study area adjacent to the Suwannee River that consists predominantly of agricultural land use, 18 wells tapping the Upper Floridan aquifer and 7 springs were sampled three times during 1990 through 1994 for major dissolved inorganic constituents, trace elements, and nutrients. During a period of above normal rainfall that resulted in high river stage and high ground water levels in 1991, the combination of increased amounts of dissolved organic carbon and decreased levels of dissolved oxygen in ground water created conditions favorable for the natural reduction of nitrate by denitrification reactions in the aquifer. As a result, less nitrate was discharged by ground water to the Suwannee River

The Role of Sarvak Formation in Supplying Pol-e Dokhtar Town (Iran) with Drinking Water, 2002, Ahmadipour, Mohamad Reza

The Sarvak formation is the most karstified formation of the Bageston group, NW from town Pol-e Dokhtar. Its southern limb is karstified and the most important for the ground water. Three wells were drilled for supplying the drinking water to Pol-e Dokhtar. The pumping test (72 hours) was carried out. Analyses of oxygen-18 and deuterium indicated that the water is of meteoric origin. Water from the well1 has the minimal and from the well3 maximal concentrations of tritium which indicate different residence time. Chemical analyses show that the water is of Ca>Mg>Na and HCO3>SO4>Cl type. During the drilling water samples had relatively high NO3 (27 mg/l), which was reduced due to the protection of the area from agricultural activities. Due to this study, the town of Pol-e Dokhtar, which was facing serious problem of drinking water since before the Islamic Republic of Iran, has been solved.


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

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

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


Use of stable isotopes to quantify flows between the Everglades and urban areas in Miami-Dade County Florida, 2004, Wilcox W. M. , Sologabriele H. M. , Sternberg L. O. R. ,
An isotopic study was performed to assess the movement of groundwater for a site located in Miami-Dade County, Florida. The site encompasses portions of a protected wetland environment (northeast Everglades National Park) and suburban residential Miami, incorporating municipal pumping wells and lakes formed by rock mining. Samples of ground, surface, and rainwater were analyzed for their isotopic composition (oxygen-18 and deuterium). Various analytical and graphical techniques were used to analyze this data and two conceptual box models were developed to quantify flows between different regions within the site. Results from this study indicate that the aquifer underlying the study site (the Biscayne aquifer) is highly transmissive with the exception of two semi-confining layers of reduced hydraulic conductivity. Everglades surface water infiltrates into the aquifer and migrates east toward residential areas. In these urban areas, 'shallow' groundwater (above the deeper semi-confining layer) is substantially affected by urban rainfall while 'deep' groundwater (below the deeper semi-confining layer) maintains a composition similar to that of Everglades water. Rock mining lakes in the area provide 'breaks' in the semi-confining layers that allow for mixing of shallow and deep groundwater. As water travels eastward, municipal well intakes, screened to a depth below the deeper semi-confining layer, draw upon not only shallow urban water (predominantly comprised of urban rainfall) and lake water (having influences from both urban rainfall and Everglades water) but also deep water that originated in the Everglades. Results from one of the box models estimate that over 60% of the water being removed by municipal pumping originated in the Everglades. These conclusions suggest that Everglades water, both directly through deep groundwater flow and indirectly through mixing with rock-mining lakes, is being drawn into the operating municipal wellfield.

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.

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

Water storage and transfer in the epikarst of karstic systems during high flow periods, 2006, Aquilina L, Ladouche B, Dorfliger N,
SummaryA monitoring of spring and rain waters in the South of France during two hydrological cycles is presented. Rain waters were sampled after each precipitation event at 3 rain-gauge stations. Four karstic springs located in the same area have also been daily (high discharge events) to monthly (low flow periods) sampled. This paper focuses on compositional changes in the Cl- and Br- ions and the oxygen-18 ([delta]18O) and hydrogen ([delta]D) isotopes during the high discharge events.The responses of the different karstic systems are quite homogeneous and reflect the hydrological state of the system. The waters discharged during the major autumn and winter high discharge events originate from the epikarstic reservoir and show characteristics chemical variations related to residence in the unsaturated zone close to the surface. Their residence time in the order of 1-3 months. Correlations between the composition of the spring-water and the rainwater during three successive high discharge events during the summer of 1998 indicate that the water for high discharge event 'n' is derived from water from precipitation event 'n - 1' via a piston-type mechanism with residence time of 2 weeks.These results are interpreted as an indication of the major role of the epikarst reservoir in the karst recharge functioning. The similar behaviour of the four springs, although located in different geological contexts allows to think that the epikarst role could be more important than previously thought

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