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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 albedo is the ratio of reflected radiation to total radiation on a natural surface [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 predictions (Keyword) returned 27 results for the whole karstbase:
Showing 1 to 15 of 27
Some Implications of Competition for Cave Stream Communities., 1981, Culver David C.
Based on recent theoretical work by Robert May and Richard Levins, two hypotheses about time fluctuations in abundance of competing species were generated. Data for isopods and amphipods from four cave stream communities in Virginia and West Virginia were used to test the predictions. First, variance of total abundance should be less than the sum of the variances of individual species' abundances. In three of four communities studied, the prediction was confirmed, but none were statistically significant. Positive correlations among carrying capacities of competing species may explain the poor agreement with predictions. Second, the signs of 19 correlations and partial correlations of species abundances were predicted on the basis of relative magnitudes of direct and indirect effects of competition, and of these predictions, 16 were confirmed by the data, including 5 statistically significant ones. Most interesting was the finding that competitors can be positively correlated.

Karst hydrogeology of the Canadian Rocky Mountains, PhD Thesis, 1991, Worthington, Stephen Richard Hurst

An analysis of the discharge and hydrochemical variations of contrasting springs at Crowsnest Pass showed they were part of a vertical hierarchy in the aquifer, in which underflow and overflow components play a dominant role. It was found that karst springs at Crowsnest Pass and elsewhere show a range between two end members. Thermal springs have long, deep flow paths, with high sulphate concentrations, low discharge variance and low flow velocities. Overflow springs have local shallow flow paths, low sulphate, high discharge variance, and high flow velocities. Intermediate between these end members are underflow springs; in the Rocky Mountains these are mostly aggraded, and give the sustained winter flow and high sulphate concentrations found in major rivers. It was found that underflow or overflow behaviour is able to explain most of the contrasts found between karst springs in discharge and sulphate concentrations. Conversely, differences in bicarbonate concentration are principally due to the ratio of allogenic to autogenic recharge to the aquifer. Hydraulic analysis showed that gradients decrease in the downstream direction, and are typically 0.0001-0.05 at maximum discharges, that friction factors vary by a factor of $>$1000, and that most active conduits have closed-channel flow and are in dynamic equilibrium with sediment supply. The analysis of the hydrological data from Crowsnest Pass and elsewhere has led to the development of a new conceptual model for groundwater flow in karst, in which the Hagen-Poiseuille flow net conditions the aquifer for conduit development, and determines where the conduits will be. The model explains why most conduits are in dynamic equilibrium with sediment supply, why temperate karst springs are mostly vauclusian, what the mean time for speleogenesis is, how $>$98% of the solution of limestone is in the surficial zone, and why there are karstic hot springs in the Rocky Mountains and elsewhere. The model enables predictions to be made of sink to resurgence flow velocities, of conduit depth below the water table, of the ratio of beds to joints used by conduits, of the spacing between cave tiers, and of the depth of vauclusian springs. This new understanding of how karstic aquifers develop and function gives a powerful predictive ability to karst hydrogeology.


GEOCHEMICALLY CONTROLLED CALCITE PRECIPITATION BY CO2 OUTGASSING - FIELD-MEASUREMENTS OF PRECIPITATION RATES IN COMPARISON TO THEORETICAL PREDICTIONS, 1992, Dreybrodt W, Buhmann D, Michaelis J, Usdowski E,

USING GROUND-PENETRATING RADAR TO INVESTIGATE A SUBSURFACE KARST LANDSCAPE IN NORTH-CENTRAL FLORIDA, 1994, Collins Me, Cum M, Hanninen P,
Doline formation in karst areas has been a major concern in Florida. Recently, there has been increased interest in investigating the subsurface conditions that influences preferential flow in these karst landscapes. This information is necessary to improve transport and fate models of contaminants. In addition, there is interest in knowing if the formation and expansion of dolines can be predicted by studying subsurface conditions and flow patterns. The soils on the Newberry Limestone Plain are typically sandy above a thin or absent phosphatic, clayey Hawthorne Formation. Underlying this formation is the Crystal River Limestone. A field survey with ground-penetrating radar (GPR) was conducted on the Newberry Limestone Plain at a site with recently formed dolines. The objectives were (i) to investigate the subsurface materials, (ii) to ascertain subsurface landscape variability, (iii) to relate the subsurface landscapes to subsurface flow patterns, and (iv) to predict doline growth and formation in the study area. The results of this study indicated that the subsurface features; presence of clay over limestone, location of solution pipes and paleo-dolines are variable. In general, the subsurface landscape does not follow the surface topography. Subsurface solute movement can be estimated in these landscapes assuming the clay layer that drapes the limestone acts as an aquatarde. Thus, subsurface modeling of flow at the study site is improved. Locations of paleo-dolines and solution pipes were obvious in the radar data. Predictions, though, of future doline formation and growth at the study site were difficult with GPR. Fracture patterns, e.g. dips in the limestone, can be evaluated and weak zones where paleo-dolines have formed can be identified. This study would not have been possible without the use of the GPR. The radar was able to obtain continuous information on 16% of the site to a depth of 3 m. A highly detailed soil survey using conventional methods would have provided only 0.8% coverage of the site

ESTIMATION OF PREFERENTIAL MOVEMENT OF BROMIDE TRACER UNDER FIELD CONDITIONS, 1994, Jabro J. D. , Lotse E. G. , Fritton D. D. , Baker D. E. ,
Leaching of agricultural chemicals from the root and vadose zones into groundwater is an important environmental concern. To procure a better understanding of the movement and transport of agricultural chemicals through the soil profile, a field research study was conducted to estimate bromide leaching losses under saturated conditions where preferential flow is occurring. The field data were then used to evaluate the LEACHM model. Eighteen double-ring infiltrometers were used to apply a pulse (100 mm depth) of bromide tracer on two previously saturated soils located in a karst region of southeastern Pennsylvania. Internal drainage over the next seven days resulted in nearly 51 % of the applied Br- being leached to a depth below 0.80 m. The LEACHM model was used to simulate the amount of bromide leached in each infiltrometer. The model predicted, accurately, an average of 46% of the applied Br- leached below the 0.80 m depth. Mcan values of bromide concentration in the soil profile were predicted within two standard deviations of the measured mean for all depths except for the 0.20-0.40 m depth increment where the model overpredicted the bromide concentration. The model predictions of Br- leached were tested against field measurements using several statistical tests. The LEACHM model performed adequately under preferential flow conditions, perhaps because the infiltration rate at each site was used as a model input. This, actually, is some measure of the macropore flow process and suggests that simple models such as LEACHM can be used in the field, as long as a distribution of infiltration rates is used as an input

Using ground-penetrating radar to investigate a subsurface karst landscape in north-central Florida, 1994, Collins M. E. , Cure M. , Hanninen P.

Doline formation in karst areas has been a major concern in Florida. Recently, there has been increased interest in investigating the subsurface conditions that influences preferential flow in these karst landscapes. This information is necessary to improve transport and fate models of contaminants. In addition, there is interest in knowing if the formation and expansion of dolines can be predicted by studying subsurface conditions and flow patterns. The soils on the Newberry Limestone Plain are typically sandy above a thin or absent phosphatic, clayey Hawthorne Formation. Underlying this formation is the Crystal River Limestone. A field survey with ground-penetrating radar (GPR) was conducted on the Newberry Limestone Plain at a site with recently formed dolines. The objectives were (i) to investigate the subsurface materials, (ii) to ascertain subsurface landscape variability, (iii) to relate the subsurface landscapes to subsurface flow patterns, and (iv) to predict doline growth and formation in the study area. The results of this study indicated that the subsurface features; presence of clay over limestone, location of solution pipes and paleo-dolines are variable. In general, the subsurface landscape does not follow the surface topography. Subsurface solute movement can be estimated in these landscapes assuming the clay layer that drapes the limestone acts as an aquatarde. Thus, subsurface modeling of flow at the study site is improved. Locations of paleo-dolines and solution pipes were obvious in the radar data. Predictions, though, of future doline formation and growth at the study site were difficult with GPR. Fracture patterns, e.g. dips in the limestone, can be evaluated and weak zones where paleo-dolines have formed can be identified. This study would not have been possible without the use of the GPR. The radar was able to obtain continuous information on 16% of the site to a depth of 3 m. A highly detailed soil survey using conventional methods would have provided only 0.8% coverage of the site


Recent flowstone growth rates: field measurements and comparison to theoretical results, 1995, Baker A. , Smart Pl. ,
The model of calcite precipitation kinetics of D. Buhmann and W. Dreybrodt, based on the rate laws of L.N. Plummer et al., is used to predict cave flowstone growth rates. These theoretically modelled growth rates are compared to actual growth rates of recent samples found in cave and mine sites in southwest England. A good agreement is found between modelled and actual growth rates within the 95% confidence level of the determinations, although in general modelled growth rates overestimate actual growth rate by between 2.4 and 4.7 times. Several reasons for this overestimation are discussed, including uncertainties arising from the experimental data of L.N. Plummer et al., seasonal shut-off of water flow onto the flowstones and significant variations in the growth rate determining parameters during the period of flowstone growth. For one flowstone an underestimation of growth rate is observed and is explained by the presence of rimstone pools which pond water on the sample surface

The kinetics of the reaction CO2?>H? as one of the rate limiting steps for the dissolution of calcite in the system H2O-CO2-CaCO3, 1996, Dreybrodt W, Lauckner J, Liu Zh, Svensson U, Buhmann D,
Dissolution of CaCO3 in the system H2O-CO2-CaCO3 is controlled by three rate-determining processes: The kinetics of dissolution at the mineral surface, mass transport by diffusion, and the slow kinetics of the reaction H2O CO2 = H HCO3-. A theoretical model of Buhmann and Dreybrodt (1985a,b) predicts that the dissolution rates depend critically on the ratio V/A of the volume V of the solution and the surface area A of the reacting mineral. Experimental data verifying these predictions for stagnant solutions have been already obtained in the range 0.01 cm < V/A < 0.1 cm. We have performed measurements of dissolution rates in a porous medium of sized CaCO3 particles for V/A in the range of 2 . 10(-4) cm and 0.01 cm in a system closed with respect to CO2 using solutions pre-equilibrated with an initial partial pressure of CO2 of 1 . 10(-2) and 5 . 10(-2) atm. The results are in satisfactory agreement with the theoretical predictions and show that especially for V/A < 10(-3) cm dissolution is controlled entirely by conversion of CO2 into H and HCO3-, whereas in the range from 10(-3) cm up to 10(-1) cm both CO2-conversion and molecular diffusion are the rate controlling processes. This is corroborated by performing dissolution experiments using 0.6 mu molar solutions of carbonic anhydrase, an enzyme enhancing the CO2-conversion rates by several orders of magnitude. In these experiments CO2 conversion is no longer rate limiting and consequently the dissolution rates of CaCO3 increase significantly. We have also performed batch experiments at various initial pressures of CO2 by stirring sized calcite particles in a solution with V/A = 0.6 cm and V/A = 0.038 cm. These data also clearly show the influence of CO2-conversion on the dissolution rates. In all experiments inhibition of dissolution occurs close to equilibrium. Therefore, the theoretical predictions are valid for concentrations c less than or equal to 0.9 c(eq). Summarising we find good agreement between experimental and theoretically predicted dissolution rates. Therefore, the theoretical model can be used with confidence to find reliable dissolution rates from the chemical composition of a solution for a wide field of geological applications

Precipitation kinetics of calcite in the system CaCO3-H2O-CO2: The conversion to CO2 by the slow process H?->CO2? as a rate limiting step, 1997, Dreybrodt W, Eisenlohr L, Madry B, Ringer S,
Precipitation rates of CaCO3 from supersaturated solutions in the H2O - CO2 - CaCO3 system are controlled by three rate-determining processes: the kinetics of precipitation at the mineral surface, mass transport of the reaction species involved to and from the mineral surface, and the slow kinetics of the overall reaction HCO3- H --> CO2 H2O. A theoretical model by Buhmann and Dreybrodt (1985a,b) taking these processes into account predicts that, due to the slow kinetics of this reaction, precipitation rates to the surface of CaCO3 minerals depend critically on the ratio V/A of the volume V of the solution to the surface area A of the mineral in contact with it, for both laminar and turbulent flow. We have performed measurements of precipitation rates in a porous medium of sized particles of marble, limestone, and synthetic calcite, with V/A ratios ranging from 3.10(-4) to 1.2-10(-2) cm at 10 degrees C. Calcite was precipitated from supersaturated solutions with [Ca2] approximate to 4 mmol/L and an initial P-CO2 of 5.10(-3) or 1.10(-3) atm, respectively, using experimental conditions which prevented exchange of CO2 with the atmosphere, i.e., closed system. The results are in qualitative agreement with the theoretical predictions. Agreement with the observed data, however, is obtained by modifying the rate law of Plummer et al. (1978) to take into account surface-controlled inhibition effects. Experiments with supersaturated solutions containing carbonic anhydrase, an enzyme which enhances the conversion of HCO3- into CO2, yield rates increased by a factor of up to 15. This provides for the first time unambiguous experimental evidence that this reaction is rate limiting. We have also measured precipitation rates in batch experiments, stirring sized mineral particles in a solution with V/A ranging from 0.03 to 0.75 cm. These experiments also give clear evidence on the importance of the conversion of HCO3- into CO2 as rate limiting step. Taken together our experiments provide evidence that the theoretical model of Buhmann and Dreybrodt (1985a,b) can be used to predict reliable rates from the composition of CaHCO3- solutions with low ionic strength in many geologically relevant situations. Copyright (C) 1997 Elsevier Science Ltd

Protactinium-231 Dating of Carbonates by Thermal Ionization Mass Spectrometry: Implications for Quaternary Climate Change, 1997, Edwards Rl, Cheng H, Murrell Mt, Goldstein Sj,
Measurement of protactinium-231 ($^{231}$Pa) in carbonates by thermal ionization mass spectroscopy yields $^{231}$Pa ages that are more than 10 times more precise than those determined by decay counting. Carbonates between 10 and 250,000 years old can now be dated with $^{231}$Pa methods. Barbados corals that have identical $^{231}$Pa and thorium-230 ($^{230}$Th) ages indicate that the timing of sea level change over parts of the last glacial cycle is consistent with the predictions of the Astronomical Theory. Two Devils Hole calcite subsamples record identical $^{231}$Pa and $^{230}$Th ages, suggesting that the chronology of this climate record is accurate

Linear and nonlinear input/output models for karstic springflow and flood prediction at different time scales, 1999, Labat D. , Ababou R. , Mangin A. ,
Karstic formations function as three-dimensional (3D) hydrological basins, with both surface and subsurface flows through fissures, natural conduits, underground streams and reservoirs. The main characteristic of karstic formations is their significant 3D physical heterogeneity at all scales, from fine fissuration to large holes and conduits. This leads to dynamic and temporal variability, e.g, highly variable flow rates, due to several concurrent flow regimes with several distinct response times. The temporal hydrologic response of karstic basins is studied here from an input/output, systems analysis viewpoint. The hydraulic behaviour of the basins is approached via the relationship between hydrometeorological inputs and outputs. These processes are represented and modeled as random, self-correlated and cross-correlated, stationary time processes. More precisely, for each site-specific case presented here, the input process is the total rainfall on the basin and the output process is the discharge rate at the outlet of the basin (karstic spring). In the absence of other data, these time processes embody all the available information concerning a given karstic basin. In this paper, we first present a brief discussion of the physical structure of karstic systems. Then, we formulate linear and nonlinear models, i.e. functional relations between rainfall and runoff, and methods for identifying the kernel and coefficients of the functionals (deterministic vs. statistical; error minimisation vs. polynomial projection). These are based mostly on Volterra first order (linear) or second order (nonlinear) convolution. In addition, a new nonlinear threshold model is developed, based on the frequency distribution of interannual mean daily runoff. Finally, the different models and identification methods are applied to two karstic watersheds in the french Pyrenees mountains, using long sequences of rainfall and spring outflow data at two different sampling rates (daily and semi-hourly). The accuracy of nonlinear and linear rainfall-runoff models is tested at three time scales: long interannual scale (20 years of daily data), medium or seasonal scale (3 months of semi-hourly data), and short scale or 'flood scale' (2 days of semi-hourly data). The model predictions are analysed in terms of global statistical accuracy and in terms of accuracy with respect to high flow events (floods)

Role of cave information in environmental site characterization,, 1999, Jancin M.
For consultants concerned with developing site-specific conceptual models for flow and transport in karst, cave information can be worth accessingAt the scale of the basin, caves often display patterns that correlate with both the flow and recharge characteristics of their aquifersCharacterization of overall basin hydrology bolsters predictions and monitoring recommendations which address the siteAlthough the presence of caves beneath or near sites is rare, site-based information such as water-table maps (under both natural and pumping conditions), well water-level fluctuations, well turbidity observations, borehole-void yields during drilling, and dye-trace results, are potentially useful in defining conduit-flow boundaries to diffuse-flow blocksThe appropriate choice of dye-tracer methods should acknowledge whether most site conduits (or borehole voids, or even caves) are within the epikarst, the vadose zone, the phreatic zone, or the oscillation zoneFor inferences on site flow directions, it is useful to compare the directional frequencies of cave passages and joints, faults, and photolinears in the areaThere is evidence that where caves are well developed, there tends to be a low correlation between photolinear locations and relatively high well yieldsLNAPL migration will be retarded where main conduits are well beneath the water table, but an extensive overlying system of saturated epikarstic pores serve as trapsKarst with high seasonal or storm variations in water level will tend to repeatedly remobilize LNAPLsGiven sufficient volume, DNAPLs can penetrate vertically integrated networks of pores, fractures, or solution conduits to great depthHowever, where such pathway networks are lie above relatively tight lithologies at shallow depth, and are not sediment filled, lateral movement can greatly exceed vertical movementCharacterization of the 3-D nature of pores and pathways is an important element in understanding the migration of free product, and therefore in understanding the evolution of associated aqueous plumes

Structural effects on carbonate aquifers, 1999, Sasowsky I. D
Structural geology affects the behavior of karst aquifers by controlling the overall placement and orientation of the limestone and through fracturesThe placement and orientation affect the position of recharge and discharge boundaries to the system, while the fractures serve as pathways for water movementWhen creating a conceptual or numerical model of a karst site, it is useful and cost-efficient to consider all of these effects, as well as the geologic and geomorphic history of the areaBy understanding structural controls on the genesis of the aquifer, predictions can be made regarding current-day behavior in terms of heterogeneity and anisotropy of flowBecause conduits and fissures mainly form along structurally created discontinuities, structural data can be very useful for understanding aquifer behavior, and determining specific high-conductivity flowpaths

Three-dimensional flow measurements in rock fractures, 1999, Dijk P. , Berkowitz B.

Nuclear magnetic resonance imaging is applied to measure flow patterns in natural, water-saturated, rough-walled rock fractures. From three-dimensional water density and velocity vector images the fracture morphology and flow patterns are determined. The parabolic nature and asymmetry of the velocity profiles, and thus the accuracy of local cubic law flow rate predictions, vary greatly. This depends on the degree of wall roughness. Particularly complex flow patterns are found in one sample which contains a sharp fracture wall discontinuity. A power law for the flow rate versus aperture for the low-flow region was found without considering the hydraulic gradients.


Simulation of daily and monthly stream discharge from small watersheds using the SWAT model, 2000, Spruill C. A. , Workman S. R. , Taraba J. L. ,
The Soil and Water Assessment Tool (SWAT) was evaluated and parameter sensitivities were determined while modeling daily streamflows in a small central Kentucky watershed over a two-year period. Streamflow data from 1996 were used to calibrate the model and streamflow data from 1995 were used for evaluation. The model adequately predicted the trends in daily streamflow during this period although Nash-Sutcliffe R-2 values were -0.04 and 0.19 for 1995 and 1996, respectively The model poorly predicted the timing of some peak flow values and recession rates during the last half of 1995. Excluding daily peak flow values from August to December improved the daily R-2 to 0.15, which was similar to the 1996 daily R2 value. The Nash-Sutcliffe R-2 for monthly total flows were 0.58 for 1995 and 0.89 for 1996 which were similar to values found in the literature. Since very little information was available on the sensitivity of the SWAT model to various inputs, a sensitivity analysis/calibration procedure was designed to evaluate parameters that were thought to influence stream discharge predictions. These parameters included, drainage area, slope length, channel length, saturated hydraulic conductivity, and available water capacity. Minimization of the average absolute deviation between observed and simulated streamflows identified optimum values/ranges for each parameter. Saturated hydraulic conductivity alpha baseflow factor; drainage area, channel length, and channel width were the most sensitive parameters in modeling the karst influenced watershed. The sensitivity analysis process confirmed die trace studies in the karst watershed that a much larger area contributes to streamflow than can be described by the topographic boundaries. Overall, the results indicate that the SWAT model can be an effective tool for describing monthly, runoff from small watersheds in central Kentucky that have developed on karat hydrology however calibration data are necessary to account for solution channels draining into or out of the topographic watershed

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