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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 medium sand is grain particle with a diameter of 0.25 to 0.5 mm [16].?

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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 electrical conductivity (Keyword) returned 38 results for the whole karstbase:
Showing 1 to 15 of 38
Anomalous behaviour of specific electrical conductivity at a karst spring induced by variable catchment boundaries: the case of the Podstenjšek spring, Slovenia, , Ravbar, N. , Engelhardt, I. , Goldscheider, N.

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


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.

The governing factors of the physicochemical characteristics of Sheshpeer karst springs, Iran, 1996, Raeisi E. , Karami G. ,
The physical and chemical characteristics of karst springs are not a sole function of flow path in the carbonatic rock mass. A number of other parameters, including the type of precipitation, soil cover morphology of the exposed area, and the hydrochemistry of the infiltrating water into the karst system also have their own contribution. In the present study, the Car and Barm-Firooz mountains me chosen to determine some of the governing factors of the physical and hydrochemical characteristics of karst springs. The following measurements were carried out: 1. Concentration of major ions and electrical conductivity of the fresh snow and snowpack. 2. Variation of discharge as a function of time at six sicking streams. 3. Time Variation of discharge, electrical conductivity, and air and water temperature of sinking streams at seven sinkholes. 4. Electrical conductivity and temperature of water at the surface and 40 cm beneath the soil cover. 5. Discharge, major ions, temperature and electrical conductivity of the Sheshpeer spring water were measured every twenty days for a period of three years. The results indicate that if the physical and chemical characteristics of a karst spring are going to be used to determine the characteristics of corresponding aquifer, first the effect of external factors on the outflow should be accounted for, and then the characteristics of the karst aquifer be determined

Contemporary karst solution processes on the Tibetan Plateau, 1997, Zhang D. ,
The Tibetan Plateau, with an average elevation of 4,000-5,000 m a.s.l., is cold and arid, and geomorphologic processes are dominated by periglacial, glacial, and aeolian agents. Here, the highest known, currently-developing karst features were found during the Sino-British Expedition of 1987. Measurements of CO2 partial pressure were taken in air, soil, sediments, and caves. Also measured were the solubility of Tibetan limestones, the dissolved CaCO3 in water, and the electrical conductivity of karst waters. Field solution experiments show that CO2 partial pressure is one of the lowest in the world. Dissolved limestone content in fresh karst water is lower than in other karst areas. The solubility of the major Tibetan limestones varies little, but field experiments indicate that karst solution rates are affected by geomorphologic and climatic conditions. The formation and distribution of the present-day karst features correspond with the results of field and laboratory solution experiments. They are mainly small surface features in relatively wet and warm locations, especially where soil is in direct contact with limestone. Measurements of solution rates and CO2 content indicate that biologically stimulated solution plays an important role in karst development on this cold and arid plateau

Drip flow variations under a stalactite of the Pere Noel cave (Belgium). Evidence of seasonal variations and air pressure constraints, 1998, Genty D, Deflandre G,
The study of drip rate and seepage water electrical conductivity (hereafter called conductivity) under one stalactite in the Pere Noel cave (Belgium), with data produced from an automatic station since 1991, demonstrates several previously unobserved features: (1) measurement of drop volume shows that, for 94% of the time series, drop volume is constant (= 0.14 ml), but when discharge exceeds 48.2 drips min(-1), drop volume decreases, probably because of secondary drop formation; (2) the interannual drip rate variation is correlated to the annual water excess and its correlant, rainfall (R-2 = 0.98; exponential model); this result introduces a new improvement in the understanding of the previously investigated relationships between stalagmite annual laminae thickness and mean annual rainfall; (3) the drip rate shows a well marked seasonality: it increases abruptly in late fall or early winter and decreases slowly during spring, summer and fall. Increased discharge is accompanied by an increase in conductivity, which suggests that the flushed water is more mineralized and was stored in the karst aquifer for several months; (4) superimposed on these seasonal variations, there are two kinds of flow regimes which are driven by the atmospheric pressure: (i) a 'wiggles regime', whose duration is 1-7 days in length and which is inversely proportional to the air pressure wiggles; it is explained by either a ''shut-off faucet'' process due to the rock formation stress, or to a change in the two-phases flow component proportions (air/water); (ii) an 'unstable regime' characterized by abrupt switches (<2 h) or oscillations with variable periodicities, from a few minutes to a few hours. These occur when the drip rate reaches a threshold (i.e. 240 drops 10 min(-1)); the chaotic behaviour of this phenomenon is discussed. (C) 1998 Elsevier Science B.V. All rights reserved

Contribution of correlation and spectral analyses to the regional study of a large karst aquifer (Charente, France), 1998, Larocque M. , Mangin A. , Razack M. , Banton O. ,
The purpose of the study is to demonstrate that correlation and spectral analyses can contribute to the regional study of a large karst aquifer. An example is presented for the La Rochefoucauld karst aquifer (Charente, France). Different types of spatially distributed time series provide valuable spatio-temporal information for the karat aquifer. The available time series consist of the spring flow rates, the flow rates at different locations in sinking streams, the piezometric levels, the electrical conductivity and temperature of the water, the atmospheric pressure and the precipitation The analysis of the flow rates at the springs shows that the aquifer empties very slowly and has a large storage capacity. Hydrodynamic links were established between three of the four rivers flowing on the aquifer and the springs. The results also demonstrate the important spatial heterogeneity of the aquifer and indicate that the most rapid flow occurs in the northern part of the aquifer. Hourly piezometric and electrical conductivity time series indicate that the transmissivity of the aquifer varies when some conductive channels become desaturated during the low water period. The delays between the distributed recharge and the piezometric level, between the localized river input and the how rates at the springs and between the electrical conductivities in rivers and the main spring provide information on the travel times in the aquifer, The observation of earth tides and barometric effects indicate that this apparently unconfined aquifer has a confined behaviour. (C) 1998 Elsevier Science B.V. All rights reserved

Chemistry measurements of dripping water in Postojna Cave, 1999, Vokal Barbara, Obelić, Bogomil, Genty Dominique, Kobal Ivan

Environmental factors influencing speleothem formation such as air and water temperature as well as water properties at the surface and in the cave (pH, electrical conductivity, Ca2+, HCO3- and Mg2+ ion concentrations and drip rates) were measured during an entire year in order to follow seasonal variations. The influence of the thickness of cave roof on the water properties was also taken into consideration, and the difference between various cave water types (pool, stalactite drip waters and fast-drip waters) was followed. Monthly water samples were collected at three locations in the cave and also from the river Pivka and spring of MoËilnik. Rainwater samples were also collected and analyzed. From the results it was found that the temperature of cave waters is more or less constant during the year. Mean values of pH for all karst waters are 7.8 ± 0.2. There is a good correlation between the chemical parameters (Ca2+ and HCO3- ion concentrations and electric conductivity) and the different types of cave waters. The ratio Mg/Ca concentrations and the saturation index were determined, too.


Geophysical surveys over karst recharge features, Illinois, USA, 2001, Carpenter Pj, Ahmed S,
Karst aquifers supply a significant fraction of the world's drinking water. These types of aquifers are also highly susceptible to pollution from the surface with recharge usually occurring through fractures and solution openings at the bedrock surface. Thickness of the protective soil cover, macropores and openings within the soil cover, and the nature of the weathered bedrock surface all influence infiltration. Recharge openings at the bedrock surface, however, are often covered by unconsolidated sediments, resulting in the inadvertent placement of landfills, unregulated dump sites, tailing piles, waste lagoons and septic systems over recharge zones. In these settings surface geophysical surveys, calibrated by a few soil cores, could be employed to identify these recharge openings, and qualitatively assess the protection afforded by the soil cover. In a test of this hypothesis, geophysical measurements accurately predicted the thickness of unconsolidated deposits overlying karstic dolomite at a site about 100 km south of Chicago, Illinois. Zones of elevated electrical conductivity and high ground-penetrating radar (GPR) attenuation within the sediments coincided with subcropping solutionally-enlarged hydraulically active bedrock fractures. These fractures extend to over 12-m depth, as shown by 2-D inverted resistivity sections and soil coring. Anomalous electromagnetic (EM) conductivity and GPR response may be due to higher soil moisture above these enlarged fractures. An epikarstal conduit at 2.5-m depth was directly identified through a GPR survey. These results suggest that surface geophysical surveys are a viable tool for assessing the susceptibility of shallow karst aquifers to contamination

Inferring source waters from measurements of carbonate spring response to storms, 2002, Desmarais K, Rojstaczer S,
We infer information about the nature of groundwater flow within a karst aquifer from the physical and chemical response of a spring to storm events. The spring discharges from the Maynardville Limestone in Bear Creek Valley, Tennessee. Initially, spring discharge peaks approximately 1-2 h from the midpoint of summer storms. The initial peak is likely due to surface loading, which pressurizes the aquifer and results in water moving out of storage. All of the storms monitored exhibited recessions that follow a master recession curve very closely, indicating that storm response is fairly consistent and repeatable, independent of the time between storms and the configuration of the rain event itself. Electrical conductivity initially increases for 0.5-2.9 days (longer for smaller storms), the result of moving older water out of storage. This is followed by a 2.1-2.5 day decrease in conductivity, resulting from an increasing portion of low conductivity recharge water entering the spring. Stable carbon isotope data and the calcite saturation index of the spring water also support this conceptual model. Spring flow is likely controlled by displaced water from the aquifer rather than by direct recharge through the soil zone. (C) 2002 Elsevier Science B.V. All rights reserved

Coastal and submarine karstic discharges in theGokova Bay, SW Turkey, 2002, Bayari Cs, Kurttas T,
Hydrochemical, stable isotopic (18O and 2H) and thermal infrared data of LANDSAT 5 TM for sea surface temperature anomalies have been used to determine the extent and spatial variation of salinization in coastal and submarine karstic groundwater discharges in the Gokova Bay area, located in the SW Turkey. The bay is an active graben extending in an east-west direction. An artesian aquifer in the eastern tidal plain is the only source of fresh groundwater, whereas Tertiary and Mesozoic carbonates contacting with sea along the northern coastline provide abundant but saline water. Physical properties, major ion chemistry and stable isotope composition indicate a westward increase in the salinity of the karstic springs. The temporal variation of salinity in groundwater is either related to variations in sea level or in seasonal recharge rates, while some springs have time-invariant salinity. Submarine groundwater discharges were determined successfully from satellite images and verified by ground measurements of pH, temperature and electrical conductivity. Some of these discharges are also characterized by the existence of a halocline, as observed during Scuba diving. The westward-increasing salinity appears to be related to decreasing groundwater discharge in this direction

The Effect of Darab Salt Dome on the Quality of Adjacent Karstic and Alluvium Aquifers (South of Iran), 2002, Sharafi A. , Raeisi E. , Farhoodi G.

Karstified carbonate formations are among the most important water resources in the south-central regions of Iran. If the karst water is not contaminated by salt domes, the electrical conductivity of water in the karst aquifer is less than 500 µS cm-1 in the south-center of Iran. The study area is located in the southern flank of Shahneshin-Milk anticline, 200 km east of Shiraz. This region is situated in the Zagros Thrust Zone. The Tarbur karstic formation (Late Campanian-Maastrichtian) is outcropped on the southern flank of the Shahneshin-Milk anticline which is underlain by the impermeable Radiolarite formation. The Darab salt dome outcrops inside the karstified Tarbur Formation. Several springs emerge from the Tarbur Formation. The quality of all springs is in the range of unpolluted karst water except for three springs which are located near the Darab salt dome. The electrical conductivity of these springs range from 1200 to 2000 µS cm-1. Part of the alluvium near the Darab salt dome is salt-marsh which is bounded by two channels. The electrical conductivity in the salt-marsh below the water table is about 1400 µS cm-1, and it reduces to 400 µS cm-1 at the lower depths. Run-off from the Darab salt dome and seepage from the channel with low quality water are probably the main reasons of salt-marsh development. A considerable amount of polluted Tarbur karst water does not flow towards the marshland because, firstly, most of the Tarbur karst water discharges from the springs, and secondly, the alluvium aquifer is not affected by polluted water at lower depths.


Transfer of bacteria-contaminated particles in a karst aquifer: evolution of contaminated materials from a sinkhole to a spring, 2003, Dussartbaptista L, Massei N, Dupont Jp, Jouenne T,
The transport of particle-associated bacteria during rain events in karst waters has been investigated. In this aim, we studied the correlations between water turbidity and enumerations of sessile (attached) and planktonic (non-attached) bacteria. We monitored physicochemical, i.e. turbidity, electrical conductivity, size and nature of the transported particles, and bacteriological properties of waters since their infiltration on a karst plateau to their discharge at a karstic spring. Results showed a decrease of the concentration of sessile bacteria at the sinkhole for high turbidities. This phenomenon might be explained by the arrival of lower contaminated material. On the other hand, the amount of sessile bacteria at the spring was not influenced by the turbidity values. These data demonstrated that slightly contaminated larger particles were not recovered, whereas small-size particles, which exhibited a higher bacterial contamination, were directly transferred (i.e. not affected by intra-karstic deposition) through the aquifer. Our study highlighted some significant differences between the bacteriological time series at the sinkhole and at the spring, which characterizes the storage/resuspension function of the considered karst system. Moreover, we show a decrease of the concentration of planktonic bacteria after transport through the system whereas no reduction of the sessile population occur-red. The present data confirm that turbidity does not constitute a good indicator for bacterial contamination: if high turbidity corresponds to high bacterial contamination, low turbidity does not systematically exclude a risk of contamination by sessile organisms. (C) 2003 Elsevier B.V. All rights reserved

Assessment of direct transfer and resuspension of particles during turbid floods at a karstic spring, 2003, Massei N. , Wang H. Q. , Dupont J. P. , Rodet J. , Laignel B. ,
Turbid water can be the source of important sanitary problems in karstic regions. It is the case of the Pays de Caux, in Haute Normandie, where the main resource in drinking water is provided by the chalk aquifer. In the case of the typical binary karst of the Pays de Caux, turbidity results from the input in sinkholes of turbid surface water induced by erosion on the plateaus. At some spring tappings, water may be very turbid in period of intense rainfall. The turbidity observed at a karstic spring is a complex signal which contains a part of direct transfer and a part of resuspension of the particles being transported. The aim of this study is turbidigraph separation, which would permit to distinguish the direct transfer and resuspension components of the turbidigraph. These two components are separated by comparing the elementary surface storm-derived water fluxes and elementary turbidity signals at the spring. The procedure takes place in three phases: (i) spring hydrograph separation by means of a two components mixing model (surface water and karstic groundwater) using specific electrical conductivity, (ii) decomposition of storm-derived water flux and turbidity thanks to the second-derivative method, (iii) comparison of the transfer times (approximate tomodal times) of the elementary turbidity and surface water flux signals, respectively. The mass corresponding to direct transfer, computed after signal decomposition, is then used to re-calculate a particle recovery rate, which passes so from 514 to 373%. Relations between particle flux and hydrodynamics show that resuspension can be either the fact of the dynamics of the introduction system, or that of the chalk karstic aquifer in general (case of resuspension not associated to surface water flux). In this sense, evolution of particle flux (and consequently of turbidity) can be also a marker of the karst structure. (C) 2003 Elsevier Science B.V. All rights reserved

Apports des mthodes hydrologiques dans la comprhension des coulements en pays calcaire : exemple des bas plateaux jurassiques du haut bassin de la Marne (France), 2004, Lejeune Olivier, Devos Alain
Hydrological methods for the study of river flows in limestone areas: the Marne basin in the Jurassic low plateaux (NE France) - We investigated the geographical heterogeneity of river flows in limestone areas in the upper Marne valley (interfluves of Marne-Aube and Marne-Meuse) by using the low water profiles, the modelling of discharges and the study of physicochemical parameters. We studied five basin-slopes belonging to the Marne-basin (4500 km2) and the measures were realised between 2001 and 2003 at the time of low water periods. We used an instrument (perche intgration type Pire) in order to measure the stream flows of river water. We also measured temperature and electrical conductivity in order to identify the origin of the water. The measures allowed us to identify low water profiles of the river and we also can map the discharge in low water periods. The methods show the water flow inside a basin-slope and also hydrogeological connections to the adjacent basin-slopes. Thus, they revealed that the divergence or the concentration of discharges depends on the limits of the aquifers sections related to their morphological structure and on the differential incision of the valleys. We obtained a hydrogeological pattern of interfluves and we can distinguish between areas of water lost and areas with an increasing of water volume. We confirmed this process of water transfers, called the active stream piracy, which is often approved by hydrogeologic tracers. This active stream piracy revealed by these methods in warm or interglacial period, prepare future stream piracy of surface, collectively recognised in the beginning of cold phase.

Identification of localised recharge and conduit flow by combined analysis of hydraulic and physico-chemical spring responses (Urenbrunnen, SW-Germany), 2004, Birk S, Liedl R, Sauter M,
Karst aquifers are highly vulnerable to contamination due to the rapid transport of pollutants in conduit systems. Effective strategies for the management and protection of karst aquifers, therefore, require an adequate hydrogeological characterisation of the conduit systems. In particular, the identification and characterisation of conduits transmitting rapid, localised recharge to springs is of great interest for vulnerability assessments. In this work, it is demonstrated that localised recharge and conduit flow in a karst aquifer (Urenbrunnen catchment, southwest Germany) can be characterised by jointly analysing the hydraulic and physico-chemical responses of a spring to recharge events. Conduit volumes are estimated by evaluating time lags between increases in spring discharge and associated changes in the electrical conductivity and temperature of the discharged water. These estimates are confirmed by the results of a combined tracer and recharge test. Variations in electrical conductivity are also shown to assist in the quantification of the fast recharge component associated with short-term recharge pulses. However, spectral analysis of temperature fluctuations reveals that highly mineralised surface waters locally infiltrate into the aquifer during the winter and spring without causing significant electrical conductivity variations in the spring water. Hence, the most consistent conceptual model is obtained by a combined analysis of both physico-chemical parameters. (C) 2003 Elsevier B.V. All rights reserved

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