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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 beachrock is 1. rock composed of sand grains and/or sand-sized shell fragments cemented by calcium carbonate, commonly formed very rapidly on some beaches in tropical and sub-tropical areas. beachrock generally occurs as thin beds between bedding planes that dip seawards at angles similar to those of the beach slope [9]. 2. a friable to indurated rock consisting of sand grains of various minerals cemented by calcium carbonate; occurs in thin beds dipping seaward at less than 15n. also known as beach sandstone [10].?

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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 mass-transfer (Keyword) returned 13 results for the whole karstbase:
Geophysical applications of heat and mass transfer in turbulent pipe flow, 1971, Wigley T. , Brown C. ,

A MASS-TRANSFER MODEL FOR DISSOLUTION AND PRECIPITATION OF CALCITE FROM SOLUTIONS IN TURBULENT MOTION, 1991, Dreybrodt W, Buhmann D,

HYDRODYNAMIC CONTROL OF INORGANIC CALCITE PRECIPITATION IN HUANGLONG RAVINE, CHINA - FIELD-MEASUREMENTS AND THEORETICAL PREDICTION OF DEPOSITION RATES, 1995, Liu Z. H. , Svensson U. , Dreybrodt W. , Yuan D. X. , Buhmann D. ,
Hydrochemical and hydrodynamical investigations are presented to explain tufa deposition rates along the flow path of the Huanglong Ravine, located in northwestern Sichuan province, China, on an altitude of about 3400 m asl. Due to outgassing of CO2 the mainly spring-fed stream exhibits, along a valley of 3.5 km, calcite precipitation rates up to a few mm/year. We have carried out in situ experiments to measure calcite deposition rates at rimstone dams, inside of pools and in the stream-bed. Simultaneously, the downstream evolution of water chemistry was investigated at nine locations with respect to Ca2 Mg2, Na, Cl-, SO42-, and alkalinity. Temperature, pH, and conductivity were measured in situ, while total hardness, Ca-T, and alkalinity have been determined immediately after sampling, performing standard titration methods. The water turned out to be of an almost pure Ca-Mg-HCO3 type. The degassing of CO2 causes high supersaturation with respect to calcite and due to calcite precipitation the Ca2 concentration decreases from 6 . 10(-3) mole/l upstream down to 2.5 . 10(-3) mole/l at the lower course. Small rectangular shaped tablets of pure marble were mounted under different flow regimes, i.e., at the dam sites with fast water flow as well as inside pools with still water. After the substrate samples had stayed in the water for a period of a few days, the deposition rates were measured by weight increase, up to several tens of milligrams. Although there were no differences in hydrochemistry, deposition rates in fast flowing water were higher by as much as a factor of four compared to still water, indicating a strong influence of hydrodynamics. While upstream rates amounted up to 5 mm/year, lower rates of about 1 mm/year were observed downstream. Inspection of the marble substrate surfaces by EDAX and SEM (scanning electron microscope) revealed authigeneously grown calcite crystals of about 10 mu m. Their shape and habit are indicative of a chemically controlled inorganic origin. By applying a mass transfer model for calcite precipitation taking into account the reaction rates at the surface given by Plummer et al. (1978), slow conversion of CO2 into H and HCO3-, and diffusional mass transport across a diffusion boundary layer, we have calculated the deposition rates from the hydrochemistry of the corresponding locations. The calculated rates agree within a factor of two with the experimental results. Our findings confirm former conclusions with respect to fast flow conditions: reasonable rates of calcite precipitation can be estimated in reducing the PWP-rate calculated from the chemical composition of the water by a factor of about ten, thus correcting for the influence of the diffusion boundary layer

Dedolomitization as a driving mechanism for karst generation in Permian Blaine formation, southwestern Oklahoma, USA, 1997, Raines M. A. , Dewers T. A. ,
Cyclic deposits of Permian shales, dolomites, and halite and gypsum-bearing strata in the Blaine Formation of Southwestern Oklahoma contain abundant karst features. The present study shows that an important mechanism of karst development in these sequences is dedolomitization, wherein gypsum and dolomite in close spatial proximity dissolve and supersaturate groundwaters with respect to calcite. The net loss of mass accompanying this process (dolomite and gypsum dissolution minus calcite precipitation) can be manifest in secondary porosity development while the coupled nature of this set of reactions results in the retention of undersaturated conditions of groundwater with respect to gypsum. The continued disequilibrium generates karst voids in gypsum-bearing aquifers, a mineral-water system that would otherwise rapidly equilibrate. Geochemical modeling (using the code PHRQPITZ, Plummer et al 1988) of groundwater chemical data from Southwestern Oklahoma from the 1950's up to the present suggests that dedolomitization has occurred throughout this time period in evaporite sequences in Southwestern Oklahoma. Reports from groundwater well logs in the region of vein calcite suggest secondary precipitation, an observation in accord with dedolomite formation In terms of the amounts of void space produced by dissolution, dedolomitization can dominate gypsum dissolution alone, especially in periods of quiescent aquifer recharge when gypsum-water systems would have otherwise equilibrated and karst development ceased. Mass balance modeling plus molar volume considerations show that for every cubic cm of original rock (dolomite plus gypsum), there is 0.54 cm(3) of calcite and 0.47 cm(3) of void space produced Only slightly more pore space results if the dedolomitization reaction proceeds by psuedomorphic replacement of dolomite by calcite than in a reaction mechanism based on conservation of bicarbonate

Mixed transport reaction control of gypsum dissolution kinetics in aqueous solutions and initiation of gypsum karst, 1997, Raines M. A. , Dewers T. A. ,
Experiments with gypsum in aqueous solutions at 25 degrees C, low ionic strengths, and a range of saturation states indicate a mixed surface reaction and diffusional transport control of gypsum dissolution kinetics. Dissolution rates were determined in a mixed flow/rotating disc reactor operating under steady-state conditions, in which polished gypsum discs were rotated at constant speed and reactant solutions were continuously fed into the reactor. Rates increase with velocity of spin under laminar conditions (low rates of spin), but increase asymptotically to a constant rate as turbulent conditions develop with increasing spin velocity, experiencing a small jump in magnitude across the laminar-turbulent transition. A Linear dependence of rates on the square root of spin velocity in the laminar regime is consistent with rates being limited by transport through a hydrodynamic boundary layer. The increase in rate with onset of turbulence accompanies a near discontinuous drop in hydrodynamic boundary layer thickness across the transition. A relative independence of rates on spinning velocity in the turbulent regime plus a nonlinear dependence of rates on saturation state are factors consistent with surface reaction control. Together these behaviors implicate a 'mixed' transport and reaction control of gypsum dissolution kinetics. A rate law which combines both kinetic mechanisms and can reproduce experimental results under laminar flow conditions is proposed as follows: R = k(t) {1 - Omega(b)() zeta [1 - (1 2(1 - Omega(b)())(1/2)]} where k(t) is the rate coefficient for transport control, and Omega(b)() is the mean ionic saturation state of the bulk fluid. The dimensionless parameter zeta(=Dm(eq)()/2 delta k() where m(eq)() = mean ionic molal equilibrium concentration, D is the diffusion coefficient through the hydrodynamic boundary layer, delta equals the boundary layer thickness and k() is the rate constant for surface reaction control) indicates which process, transport or surface reaction, dominates, and is sensitive to the hydrodynamic conditions in the reactor. For the range of conditions used in our experiments, zeta varies from about 1.4 to 4.5. Rates of gypsum dissolution were also determined in situ in a cavern system in the Permian Blaine Formation, southwestern Oklahoma. Although the flow conditions in the caverns were not determinable, there is good agreement between lab- and field-determined rates in that field rate magnitudes lie within a range of rates determined experimentally under zero to low spin velocities A numerical model coupling fluid flow and gypsum reaction in an idealized circular conduit is used to estimate the distance which undersaturated solutions will travel into small incipient conduits before saturation is achieved. Simulations of conduit wall dissolution showed-member behaviors of conduit formation and surface denudation that depend on flow boundary conditions (constant discharge or constant hydraulic gradient and initial conduit radius. Surface-control of dissolution rates. which becomes more influential with higher fluid flow velocity, has the effect that rate decrease more slowly as saturation is approached than otherwise would occur if rates were controlled by transport alone. This has the effect that reactive solutions can penetrate much farther into gypsum-bearing karst conduits than heretofore thought possible, influencing timing and mechanism of karst development as well as stability of engineered structures above karst terrain

Changes in the isotopic and chemical composition of ground water resulting from a recharge pulse from a sinking stream, 1998, Katz B. G. , Catches J. S. , Bullen T. D. , Michel R. L. ,
The Little River, an ephemeral stream that drains a watershed of approximately ss km(2) in northern Florida, disappears into a series of sinkholes along the Cody Scarp and flows directly into the carbonate Upper Floridan aquifer, the source of water supply in northern Florida. The changes in the geochemistry of ground water caused by a major recharge pulse from the sinking stream were investigated using chemical and isotopic tracers and mass-balance modeling techniques, Nine monitoring wells were installed open to the uppermost part of the aquifer in areas near the sinks where numerous subterranean karst solution features were identified using ground penetrating radar. During high-flow conditions in the Little River, the chemistry of water in some of the monitoring wells changed, reflecting the mixing of river water with ground water. Rapid recharge of river water into some parts of the aquifer during high-flow conditions was indicated by enriched values of delta O-18 and delta deuterium (-1.67 to -3.17 per mil and -9.2 to -15.6 per mil, respectively), elevated concentrations of tannic acid, higher (more radiogenic) Sr-87/Sr-86 ratios, and lower concentrations of Rn-222, silica, and alkalinity compared to low-how conditions. The proportion of river water that mixed with ground water ranged from 0.10 to 0.67 based on binary mixing models using the tracers O-18, deuterium, tannic acid, silica, Rn-222, and Sr-87/Sr-86. On the basis of mass-balance modeling during steady-state how conditions, the dominant processes controlling carbon cycling in ground water are the dissolution of calcite and dolomite in aquifer material, and aerobic degradation of organic matter. (C) 1998 Elsevier Science B.V. All rights reserved

Characterisation of water transfer in a low temperature convective wood drier: influence of the operating parameters on the mass transfer coefficient, 1999, Chrusciel L, Mougel E, Zoulalian A, Meunier T,

Inverse modeling of the hydrological and the hydrochemical behavior of hydrosystems: Characterization of karst system functioning, 2001, Pinault J. L. , Plagnes V. , Aquilina L. , Bakalowicz M. ,
Inverse modeling of mass transfer characterizes the dynamic processes affecting the function of karst systems and can be used to identify karst properties. An inverse model is proposed to calculate unit hydrographs as well as impulse response of fluxes from rainfall-runoff or rainfall-flux data, the purpose of which is hydrograph separation. Contrary to what hydrologists have been doing for years, hydrograph separation is carried out by using transfer functions in their entirety, which enables accurate separation of fluxes, as was explained in the companion paper [Pinault et al., this issue]. The unit hydrograph as well as impulse response of fluxes is decomposed into a quick and a slow component, and, consequently, the effective rainfall is decomposed into two parts, one contributing to the quick flow (or flux) and the other contributing to the slow flow generation. This approach is applied to seven French karstic aquifers located on the Larzac plateau in the Grands Causses area (in the south of France). Both hydrodynamical and hydrogeochemical data have been recorded from these springs over several hydrological cycles. For modeling purposes, karst properties can be represented by the impulse responses of flow and flux of dissolved species. The heterogeneity of aquifers is translated to time-modulated flow and transport at the outlet. Monitoring these fluxes enables the evaluation of slow and quick components in the hydrograph. The quick component refers to the 'flush flow' effect and results from fast infiltration in the karst conduit network when connection is established between the infiltration and phreatic zones, inducing an increase in water head. This component reflects flood events where flow behavior is nonlinear and is described by a very short transfer function, which increases and decreases according to water head. The slow component consists of slow and fast infiltration, underground runoff, storage in annex-to-drain systems, and discharge from the saturated zone. These components can be further subdivided by measuring chemical responses at the karst outlet. Using Such natural tracers enables the slow component of the unit hydrograph to be separated into preevent water, i.e., water of the reservoir and event water, i.e., water whose origin can be related to a particular rainfall event. These measurements can be used to determine the rate of water renewal. Since the preevent water hydrograph is produced by stored water when pushed by a rainfall event and the event water hydrograph reflects rainwater transfer, separating the two components can yield insights into the characteristics of karst aquifers, the modes of infiltration, and the mechanisms involved in karstification, as well as the degree of organization of the aquifer

Microscopic simulations of fracture dissolution, 2004, Szymczak P. , Ladd A. J. C.

Microscopic simulations of fracture dissolution are  reported, taking account of the explicit topography of the  pore space, the transport of reactants and products, and the  chemical kinetics at the solid surfaces. A three-dimensional  numerical model has been constructed, in which the fluid  velocity field is calculated with an implicit lattice-Boltzmann  method, and the transport of dissolved species is modeled by  an innovative random walk algorithm that incorporates the  chemical kinetics at the solid surfaces. The model contains no  free parameters or semi-empirical mass-transfer coefficients.  The simulated morphological changes in a complex fracture  are compared with recent laboratory experiments [Detwiler et  al., 2003] with the same initial topography. 


Dissolution of limestone fractures by cooling waters: Early development of hypogene karst systems, 2005, Andre Bj, Rajaram H,

[1] Fracture dissolution in the early stages of karstification under hypogene conditions is investigated using a coupled numerical model of fluid flow, heat transfer, and reactive transport. Dissolution of calcite in the H2O-CO2-CaCO3 system along a cooling flow path is investigated using both equilibrium and kinetic models. During the very early stages of fracture growth, there is a positive feedback between flow, heat transfer, and dissolution. In this stage the dissolution rate is largely controlled by the retrograde solubility of calcite, and aperture growth is relatively uniform along the fracture length. There is a period of slow continuous increase in the mass flow rate through the fracture, which is followed by an abrupt rapid increase. We refer to the time when this rapid increase occurs as the maturation time. As the flow rate continues to increase after maturation, forced convective effects lead to higher fluid temperatures in the fracture, resulting in a negative feedback that slows the rate of fracture growth. The behavior of aperture growth before the maturation time can be described by a simple ordinary differential equation. The solution of this differential equation provides an estimate of the maturation time, in terms of the initial aperture, hydraulic and thermal gradients, and the change in solubility with temperature. The behavior before maturation in two-dimensional variable aperture fractures is investigated using a simplified model. The maturation time is shown to decrease with the degree of aperture variability due to highly selective growth along preferential flow paths


Stable isotope data as constraints on models for the origin of coralloid and massive speleothems: The interplay of substrate, water supply, degassing, and evaporation, 2015, Caddeo Guglielmo A. , Railsback L. Bruce, Dewaele Jo, Frau Franco

Many speleothems can be assigned to one of two morphological groups: massive speleothems, which consist of compact bulks of material, and coralloids, which are domal to digitate in form. Faster growth on protrusions of the substrate occurs in the typical growth layers of coralloids (where those layers are termed “coralloid accretions”), but it is not observed in the typical layers of massive speleothems, which in contrast tend to smoothen the speleothem surface (and can therefore be defined as "smoothing accretions"). The different growth rates on different areas of the substrate are explainable by various mechanisms of CaCO3 deposition (e.g., differential aerosol deposition, differential CO2 and/or H2O loss from a capillary film of solution, deposition in subaqueous environments). To identify the causes of formation of coralloids rather than massive speleothems, this article provides data about d13C and d18O at coeval points of both smoothing and coralloid accretions, examining the relationship between isotopic composition and the substrate morphology. In subaerial speleothems, data show an enrichment in heavy isotopes both along the direction of water flow and toward the protrusions. The first effect is due to H2O evaporation and CO2 degassing during a gravity-driven flow of water (gravity stage) and is observed in smoothing accretions; the second effect is due to evaporation and degassing during water movement by capillary action from recesses to prominences (capillary stage) and is observed in subaerial coralloids. Both effects coexist in smoothing accretions interspersed among coralloid ones (intermediate stage). Thus this study supports the origin of subaerial coralloids from dominantly capillary water and disproves their origin by deposition of aerosol from the cave air. On the other hand, subaqueous coralloids seem to form by a differential mass-transfer from a still bulk of water towards different zones of the substrate along diffusion flux vectors of nutrients perpendicular to the isodepleted surfaces. Finally, this isotopic method has proved useful to investigate the controls on speleothem morphology and to obtain additional insights on the evolution of aqueous solutions inside caves.


Stable isotope data as constraints on models for the origin of coralloid and massive speleothems: The interplay of substrate, water supply, degassing, and evaporation, 2015,

Many speleothems can be assigned to one of two morphological groups: massive speleothems, which consist of compact bulks of material, and coralloids, which are domal to digitate in form. Faster growth on protrusions of the substrate occurs in the typical growth layers of coralloids (where those layers are termed “coralloid accretions”), but it is not observed in the typical layers of massive speleothems, which in contrast tend to smoothen the speleothem surface (and can therefore be defined as "smoothing accretions"). The different growth rates on different areas of the substrate are explainable by various mechanisms of CaCO3 deposition (e.g., differential aerosol deposition, differential CO2 and/or H2O loss from a capillary film of solution, deposition in subaqueous environments). To identify the causes of formation of coralloids rather than massive speleothems, this article provides data about d13C and d18O at coeval points of both smoothing and coralloid accretions, examining the relationship between isotopic composition and the substrate morphology. In subaerial speleothems, data show an enrichment in heavy isotopes both along the direction of water flow and toward the protrusions. The first effect is due to H2O evaporation and CO2 degassing during a gravity-driven flow of water (gravity stage) and is observed in smoothing accretions; the second effect is due to evaporation and degassing during water movement by capillary action from recesses to prominences (capillary stage) and is observed in subaerial coralloids. Both effects coexist in smoothing accretions interspersed among coralloid ones (intermediate stage). Thus this study supports the origin of subaerial coralloids from dominantly capillary water and disproves their origin by deposition of aerosol from the cave air. On the other hand, subaqueous coralloids seem to form by a differential mass-transfer from a still bulk of water towards different zones of the substrate along diffusion flux vectors of nutrients perpendicular to the isodepleted surfaces. Finally, this isotopic method has proved useful to investigate the controls on speleothem morphology and to obtain additional insights on the evolution of aqueous solutions inside caves.


Stable isotope data as constraints on models for the origin of coralloid and massive speleothems: The interplay of substrate, water supply, degassing, and evaporation, 2015, Caddeo Guglielmo Angelo, Railsback Loren Bruce, De Waele Jo, Frau Franco

Many speleothems can be assigned to one of two morphological groups: massive speleothems, which consist of compact bulks of material, and coralloids, which are domal to digitate in form. Faster growth on protrusions of the substrate occurs in the typical growth layers of coralloids (where those layers are termed “coralloid accretions”),

but it is not observed in the typical layers of massive speleothems, which in contrast tend to smoothen the speleothem surface (and can therefore be defined as “smoothing accretions”). The different growth rates on different areas of the substrate are explainable by various mechanisms of CaCO3 deposition (e.g., differential aerosol deposition, differential CO2 and/or H2O loss fromacapillary filmof solution, deposition in subaqueous environments).

To identify the causes of formation of coralloids rather than massive speleothems, this article provides data about δ13C and δ18O at coeval points of both smoothing and coralloid accretions, examining the relationship between isotopic composition and the substratemorphology. In subaerial speleothems, data showenrichment in heavy isotopes both along the direction of water flow and toward the protrusions. The first effect is due to H2O evaporation and CO2 degassing during a gravity-driven flow of water (gravity stage) and is observed in smoothing accretions; the second effect is due to evaporation and degassing duringwatermovement by capillary action from recesses to prominences (capillary stage) and is observed in subaerial coralloids. Both effects coexist in smoothing accretions interspersed among coralloid ones (intermediate stage). Thus this study supports the origin of subaerial coralloids from dominantly capillary water and disproves their origin by deposition of aerosol fromthe cave air. On the other hand, subaqueous coralloids seem to form by a differential mass-transfer from a still bulk of water toward different zones of the substrate along diffusion flux vectors of nutrients perpendicular to the iso-depleted surfaces. Finally, this isotopic method has proved useful to investigate the controls on speleothem morphology and to obtain additional insights on the evolution of aqueous solutions inside caves.


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