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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 drawdown is 1. the vertical distance the water elevation is lowered or the reduction of the pressure head due to the removal of water [22]. 2. the decline in potentiometric surface at a point caused by the withdrawal of water from a hydrogeologic unit [22].?

Checkout all 2699 terms in the KarstBase Glossary of Karst and Cave Terms

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KarstBase a bibliography database in karst and cave science.

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 flow velocity (Keyword) returned 38 results for the whole karstbase:
Showing 16 to 30 of 38
Physical Mechanisms of River Waterfall Tufa (Travertine) Formation, 2001, Zhang David Dian, Zhang Yingjun, Zhu An, Cheng Xing,
Waterfall tufa is widely distributed around the world, especially in tropical and subtropical karst areas. In these areas river water is generally supersaturated with respect to calcite, and the precipitation occurs mainly at waterfall and cascade sites. Development of waterfall tufa has been described as simply being the result of water turbulence. We believe, however, that three physical effects can lead to tufa deposition at waterfall sites: aeration, jet-flow, and low-pressure effects. The three physical effects are induced by two basic changes in the water: an accelerated flow velocity, and enlargement of the air-water interface area. These two changes increase the rate of CO2 outgassing and the SIc, so that a high degree of supersaturation is achieved, which then induces calcite precipitation. These 'waterfall effects' have been simulated in laboratory and field experiments, and each of them can accelerate, or trigger, calcite precipitation. Field measurements of river water chemistry also show that tufa deposition occurred only at waterfall sites. In these experiments and observations, waterfall effects play the most important role in triggering and accelerating CO2 outgassing rates. Field and laboratory observations indicate that plants and evaporation also play important roles in tufa formation. Growth of algae and mosses on tufa surfaces can provide substrates for calcite nucleation and can trap detrital calcite, accelerating tufa deposition. However, the prerequisite for such deposition at waterfall sites is a high degree of supersaturation in river water, which is mainly caused by waterfall effects. Evaporation can lead to supersaturation in sprays and thin water films at a waterfall site and cause the precipitation of dissolved CaCO3, but the amount of such deposition is relatively small

Modeling flow in phreatic and epiphreatic karst conduits in the Holloch cave (Muotatal, Switzerland), 2001, Jeannin P. Y. ,
The Holloch cave is a site where the hydrodynamic behavior of a karst conduit network can be observed with a high degree of precision. Observed heads. discharge rates, conduit sizes, and conduit lengths have been compiled into a simple hydrodynamic model in order to check their consistency. It was possible to calibrate and satisfactorily fit the observed data. Model results show the following: (1) Flow models which are able to simulate turbulent flow in variably saturated conduit networks can adequately model conduit flow-dominated karst systems. (2) Karst systems may be strongly nonlinear, especially because of the presence of epiphreatic conduits. (3) Under certain circumstances, storage in the epiphreatic conduits and in the fissured limestone matrix can be neglected. (4) The typical effective hydraulic conductivity of karst conduits ranges between 1 and 10 m s(-1), and the Louis Formula is adequate to calculate head losses in those conduits. (5) Indirect measurements of flow velocity using scallop size indicate values of similar to 30-40% of the maximal annual discharge, and velocity derived from pebble size indicates values of similar to 150% of the maximal annual discharge

Mine water tracing, 2002, Wolkersdorfer Christian,
This paper describes how tracer tests can be used in flooded underground mines to evaluate the hydrodynamic conditions or reliability of dams. Mine water tracer tests are conducted in order to evaluate the flow paths of seepage water, connections from the surface to the mine, and to support remediation plans for abandoned and flooded underground mines. There are only a few descriptions of successful tracer tests in the literature, and experience with mine water tracing is limited. Potential tracers are restricted due to the complicated chemical composition or low pH mine waters. A new injection and sampling method ( LydiA'-technique) overcomes some of the problems in mine water tracing. A successful tracer test from the Harz Mountains in Germany with Lycopodium clavatum, microspheres and sodium chloride is described, and the results of 29 mine water tracer tests indicate mean flow velocities of between 0.3 and 1.7 m min-1

Paradox of groundwater age, 2002, Bethke Cm, Johnson Tm,
Groundwater in aquifers is generally older than expected on the basis of flow velocity, and this observation has important implications for interpreting radiometric age determinations. Hydrologists commonly account for the aging of water as it flows along streamtubes, but not for the effects of mixing old water from aquitards (or confining layers) into aquifers, because the rate of mass exchange between aquifers and aquitards can in many cases be assumed to be small. We show, however, that the effect on age of such mixing does not depend on the mixing rate; this is the paradox of groundwater age. Surprisingly, the contribution of aquitards to the age of groundwater in aquifers depends only on the ratio of fluid volume in aquitards to aquifers. This result has broad importance for understanding the relationship between groundwater flow and the distribution of radiometric age

Paradox of groundwater age: Correction, 2002, Bethke Cm, Johnson Tm,
Groundwater in aquifers is generally older than expected on the basis of flow velocity, and this observation has important implications for interpreting radiometric age determinations. Hydrologists commonly account for the aging of water as it flows along streamtubes, but not for the effects of mixing old water from aquitards (or confining layers) into aquifers, because the rate of mass exchange between aquifers and aquitards can in many cases be assumed to be small. We show, however, that the effect on age of such mixing does not depend on the mixing rate; this is the paradox of groundwater age. Surprisingly, the contribution of aquitards to the age of groundwater in aquifers depends only on the ratio of fluid volume in aquitards to aquifers. This result has broad importance for understanding the relationship between groundwater flow and the distribution of radiometric age

Underground Water Flow from the Tržiščica Sinking Stream (SE Slovenia), 2002, Kogovš, Ek Janja, Petrič, Metka

A tracing test with injection of uranine in the sinking stream Tr¾i¹èica (SE Slovenia) was carried out at the hydrological conditions of recession from medium to low waters. Concentrated flow towards the springs Tominèev studenec, Javornikov izvir and Debeljakov izvir near the village Dvor in the Krka valley was proved. Apparent flow velocities between 2.4 and 4.6 cm/s were obtained, and the share of recovered tracer was estimated to 2/3 of the injected amount. In the Podpe¹ka jama cave the tracer in lower concentrations was detected only after heavy rain occurred after two months of low water. The apparent flow velocity of 0.1 cm/s was calculated. Obtained results, together with the outcomes of the previous tracing tests, indicate that hydrological conditions significantly influence the underground water flow from the Tr¾i¹èica sinking stream.

Measurement and analysis of dissolution patterns in rock fractures, 2002, Dijk P. E. , Berkowitz B. , Yechieli Y.

Nuclear magnetic resonance imaging (NMRI) is applied to noninvasively measure flow and dissolution patterns in natural, rough-walled, water-saturated halite fractures. Three-dimensional images of water density and flow velocity acquired with NMRI allow quantification of the developing fracture morphology and flow patterns. The flow patterns are correlated strongly to the local apertures and the large-scale wall roughness. The correlations of the dissolution patterns to the fracture morphology, flow patterns, and mineralogical composition of the rock matrix are a function of the overall dimensionless Damköhler number. At high Damköhler numbers the dissolution patterns are dominated by the flow structure. In addition, at high Damköhler numbers buoyancy (stratified flow) becomes important. In such cases the dissolution patterns also depend on the orientation and elevation of the fracture walls, resulting in preferential upward dissolution. At low Damköhler numbers the dissolution patterns depend mainly on the mineralogical composition of the rock matrix. These findings suggest that coupled flow and dissolution processes are much more complex and unpredictable than commonly assumed, even under simplified conditions.

Could Mammoth Cave be reduced to a single equation?, 2003, Groves C. G. , Meiman J.

Since the evolution of any cave system is largely deterministic, in theory the processes responsible for this development could be described mathematically. In a practical sense, we will never have such a model to realistically describe the evolution of the Mammoth Cave System in detail. However, the search itself can provide a framework within which to understand what processes are important. This can guide the design of rate process studies that would eventually be coupled to provide a comprehensive understanding of the cave's evolution. Data gaps, as well, are identified during this process.
The geometry of a cave system depends on the individual growth rates of sequential sets of passage cross-sections. The growth of each of these cross-sections is determined by a set of coupled processes, the rates of which are related to well-defined variables. Major processes include limestone dissolution and precipitation (dependent on water and rock chemistry, flow characteristics, wetted passage perimeter, and temperature), sediment entrainment, deposition, and abrasion (dependent on flow velocity distributions and properties of the sediment supply), and breakdown processes (dependent on fracture characteristics). Our ability to model the complete picture depends on our grasp of these individual behaviors, as well as their interactions.
A long-term study of the behaviors of two single active passage cross-sections is underway in the Right and Left forks of Hawkins River of Mammoth Cave, where continuous water quality data are being obtained through two 145 m deep wells. Experiments are currently underway to determine storm- and seasonal-scale changes in limestone dissolution rates. Planned studies will explore sediment dynamics and the impact of sediment masking on dissolution rates, as well as potential impacts of sediment abrasion on passage growth. Complete understanding of a single cave slice is an important step to understanding cave evolution in general.

Groundwater vulnerability map of the Chrzanow karst-fissured Triassic aquifer (Poland), 2003, Witkowski A. J. , Rubin K. , Kowalczyk A. , Rozkowski A. , Wrobel J. ,
A map shows intrinsic vulnerability to pollution of the Chrzanow karst-fissured aquifer (273 km(2)) in the southern part of Poland. This aquifer is intensively drained by numerous intakes and Zn-Pb ore mines. A DRASTIC-type parametric system was applied for groundwater vulnerability evaluation. Vulnerability assessment is based on six factors (depth to groundwater table, lithology of the unsaturated zone, net recharge, hydraulic conductivity of the aquifer, groundwater flow velocity, aquifer thickness). For the final vulnerability map construction at the scale of 1:50,000, a combination of the aquifer simulation model (using MODFLOW) and a geographical information system was applied. Maps of the net recharge, hydraulic conductivity of the aquifer and groundwater flow velocity were derived by aquifer modelling. Based on the vulnerability index (21-182), six relative vulnerability classes were selected. Reliability of the map has been verified

Colonization by aerobic bacteria in karst: Laboratory and in situ experiments, 2004, Personne J. C. , Poty F. , Mahler B. J. , Drogue C. ,
Experiments were carried out to investigate the potential for bacterial colonization of different substrates in karst aquifers and the nature of the colonizing bacteria. Laboratory batch experiments were performed using limestone and PVC as substrates, a natural bacterial isolate and a known laboratory strain (Escherichia coli [E. coli]) as inocula, and karst ground water and a synthetic formula as growth media. In parallel, fragments of limestone and granite were submerged in boreholes penetrating two karst aquifers for more than one year; the boreholes are periodically contaminated by enteric bacteria from waste water. Once a month, rock samples were removed and the colonizing bacteria quantified and identified. The batch experiments demonstrated that the natural isolate and E. coli both readily colonized limestone surfaces using karst ground water as the growth medium. In contrast, bacterial colonization of both the limestone and granite substrates, when submerged in the karst, was less intense. More than 300 bacterial strains were isolated over the period sampled, but no temporal pattern in colonization was seen as far as strain, and colonization by E. coli was notably absent, although strains of Salmonella and Citrobacter were each observed once. Samples suspended in boreholes penetrating, highly fractured zones were less densely colonized than those in the borehole penetrating a less fractured zone. The results suggest that contamination of karst aquifers by enteric bacteria is unlikely to be persistent. We hypothesize that this may be a result of the high flow velocities found in karst conduits, and of predation of colonizing bacteria by autochthonous zooplankton

Linear model describing three components of flow in karst aquifers using O-18 data, 2004, Long A. J. , Putnam L. D. ,
The stable isotope of oxygen, 180, is used as a naturally occurring ground-water tracer. Time-series data for 5 180 are analyzed to model the distinct responses and relative proportions of the conduit, intermediate, and diffuse flow components in karst aquifers. This analysis also describes mathematically the dynamics of the transient fluid interchange between conduits and diffusive networks. Conduit and intermediate flow are described by linear-systems methods, whereas diffuse flow is described by mass-balance methods. An automated optimization process estimates parameters of lognormal, Pearson type III, and gamma distributions, which are used as transfer functions in linear-systems analysis. Diffuse flow and mixing parameters also are estimated by these optimization methods. Results indicate the relative proximity of a well to a main conduit flowpath and can help to predict the movement and residence times of potential contaminants. The three-component linear model is applied to five wells, which respond to changes in the isotopic composition of point recharge water from a sinking stream in the Madison aquifer in the Black Hills of South Dakota. Flow velocities as much as 540 m/d and system memories of as much as 71 years are estimated by this method. Also, the mean, median, and standard deviation of traveltimes; time to peak response; and the relative fraction of flow for each of the three components are determined for these wells. This analysis infers that flow may branch apart and rejoin as a result of an anastomotic (or channeled) karst network. Published by Elsevier B.V

Karst groundwater: a challenge for new resources, 2005, Bakalowicz M,
Karst aquifers have complex and original characteristics which make them very different from other aquifers: high heterogeneity created and organised by groundwater flow; large voids, high flow velocities up to several hundreds of m/h, high flow rate springs up to some tens of in 3/S. Different conceptual models, known from the literature, attempt to take into account all these particularities. The study methods used in classical hydrogeology-bore hole, pumping test and distributed models-are generally invalid and unsuccessful in karst aquifers, because the results cannot be extended to the whole aquifer nor to some parts, as is done in non-karst aquifers. Presently, karst hydrogeologists use a specific investigation methodology (described here), which is comparable to that used in surface hydrology. important points remain unsolved. Some of them are related to fundamental aspects such as the void structure only a conduit network, or a conduit network plus a porous matrix -, the functioning - threshold effects and nonlinearities -, the modeling of the functioning - double or triple porosity, or viscous flow in conduits - and of karst genesis. Some other points deal with practical aspects, such as the assessment of aquifer storage capacity or vulnerability, or the prediction of the location of highly productive zones

The role of flow velocity in the vertical distribution of particulate organic matter on moss-covered travertine barriers of the Plitvice Lakes (Croatia), 2006, Milisa M. , Habdija I. , Primchabdija B. , Radanovic I. , Kepcija R. ,
We investigated the distribution patterns of particulate organic matter (POM) on travertine barriers in respect to flow velocity. Research was conducted on the barrage-lake system of the Plitvice Lakes, Croatia. Four layers were distinguished within the substrate (moss mat three travertine layers) in three hydraulic habitats at three sites. Substrate samples were collected monthly with a core sampler. The aim of the study was to explore the ability of moss mats and travertine substrate to accumulate POM; to ascertain the role of flow velocity and to produce a model of POM distribution pattern. The average of POM deposited in the 10 cm deep zone decreased significantly in the three sites along longitudinal profile of the system. Most POM was deposited in the moss mats, and the amounts decreased exponentially with depth. This was observed for coarse particulate organic matter (CPOM), ultra-fine particulate organic matter (UPOM) and total organic matter (TPOM) while fine organic matter (FPOM) deposition appeared unaffected by depth. More POM was accumulated in hydraulic habitats of low flow velocity. Correlation between flow velocity and POM accumulation was generally negative. Positive correlations between flow velocity and deposition rates were noted for CPOM in moss mats and top travertine layers; the deposition of other POM fractions was negatively influenced by the flow velocity. The influence of flow velocity decreased with increasing depth. In the deepest layers (7-10 cm) flow velocity influenced only the deposition of the smallest particles (UPOM)

Karstic behaviour of groundwater in the English Chalk, 2006, Maurice L. D. , Atkinson T. C. , Barker J. A. , Bloomfield J. P. , Farrant A. R. , Williams A. T. ,
SummaryAlthough the Chalk is only weakly karstified, tracer testing from stream sinks has demonstrated groundwater flow velocities comparable to those observed in highly karstic aquifers. Field survey of surface karst features in the catchments of the Pang and Lambourn rivers in southern England demonstrates the importance of overlying and adjacent Palaeogene strata in the development of karst features. Tracer techniques employed within the catchments enable further characterisation of the range and connectivity of solutional voids in this area of the Chalk, and allow assessment of the relative importance of different mechanisms of contaminant attenuation. Quantitative tracer test results suggest that groundwater flow may be through a complex combination of small conduits, typically 10-1000 mm in diameter, and more laterally extensive fissures with apertures of 1-50 mm. Evidence of connectivity between conduits and fissures suggest that in areas of the Chalk with rapid groundwater flow, fissures supplying abstraction boreholes may be connected to karst conduit networks with low potential for contaminant attenuation

Benchmark Papers in Karst Science, 2007,
A collection of benchmark papers in karst science: The Decade 1971 ? 1980 13. The Geochemistry of Some Carbonate Ground Waters in Central Pennsylvania, D. Langmuir 14. Genetic Interpretation of Regressive Evolutionary Processes: Studies on Hybrid Eyes of Two Astyanax Cave Populations (Characidae, Pisces), H. Wilkins 15. Cavernicoles in Lava Tubes on the Island of Hawaii, F.G. Howarth 16. Evolutionary Genetics of Cave-Dwelling Fishes of the Genus Astyanax, J.C. Avise and R.L. Selander 17. Deducing Flow Velocity in Cave Conduits from Scallops, R.L. Curl 18. The Origin of Maze Caves, A.N. Palmer 19. Foraging by Cave Beetles: Spatial and Temporal Heterogeneity of Prey, T.C. Kane and T.L. Poulson 20. Considerations of the Karst Ecosystem, R. Rouch 21. Diffuse Flow and Conduit Flow in Limestone Terrain in the Mendip Hills, Somerset (Great Britain), T.C. Atkinson 22. The Development of Limestone Cave Systems in Dimensions of Length and Depth, D.C. Ford and R.O. Ewers The Decade 1981 ? 1990 23. Magnetostratigraphy of Sediments in Mammoth Cave, Kentucky, V.A. Schmidt 24. Uranium-Series Ages of Speleothem from Northwest England: Correlations with Quaternary Climate, M. Gascoyne, D.C. Ford and H.P. Schwarcz 25. Analysis and Interpretation of Data from Tracer Tests in Karst Areas, W.K. Jones 26. Evolution of Adult Morphology and Life-History Characters in Cavernicolous Ptomaphagus Beetles, S.B. Peck 27. Ecology of the Mixohaline Hypogean Fauna along the Yugoslav Coasts, B. Sket 28. Fractal Dimensions and Geometries of Caves, R.L. Curl 29. Regional Scale Transport in a Karst Aquifer. 1. Component Separation of Spring Flow Hydrographs, S.J. Dreiss 30. Morphological Evolution of the Amphipod Gammarus minus in Caves: Quantitative Genetic Analysis, D.W. Fong 31. The Flank Margin Model for Dissolution Cave Development in Carbonate Platforms, J.E. Mylroie and J.L. Carew 32. Sulfuric Acid Speleogenesis of Carlsbad Cavern and Its Relationship to Hydrocarbons, Delaware Basin, New Mexico and Texas, C.A. Hill The Decade 1991 ? 2000 33. Origin and Morphology of Limestone Caves, A.N. Palmer 34. How Many Species of Troglobites Are There? D.C. Culver and J.R. Holsinger 35. Annual Growth Banding in a Cave Stalagmite, A. Baker, P.L. Smart, R.L. Edwards and D.A. Richards 36. Natural Environment Change in Karst: The Quaternary Record, S.-E. Lauritzen 37. Pattern and Process in the Biogeography of Subterranean Amphipods, J.R. Holsinger 38. A Chemoautotrophically Based Cave Ecosystem, S.M. Sarbu, T.C. Kane and B.K. Kinkle 39. Rhodopsin Evolution in the Dark, K.A. Crandall and D.M. Hillis 40. Climate and Vegetation History of the Midcontinent from 75 to 25 ka: A Speleothem Record from Crevice Cave, Missouri, USA, J.A. Dorale, R.L. Edwards, E. Ito and L.A. González

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