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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. ...

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. ...

Speleology in Kazakhstan

Shakalov on 11 Jul, 2012
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 compaction is a decrease in the volume of a mass of sediments from any cause. in general, compaction may be regarded as the decrease in the thickness of sediments, as a result of an increase in vertical compressive stress, and is synonymous with 'one-dimensional consolidation,' as used by engineers. the term compaction is applied both to the process and to the measured change in thickness. in thick fine-grained beds, compaction is a delayed process involving the slow escape of pore water and the gradual transfer of stress from neutral to effective. until sufficient time has passed for excess pore pressure to decrease to zero, measured values of compaction are transient [21]. see also compaction, residual; compaction, specific.?

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.
Engineering challenges in Karst, Stevanović, Zoran; Milanović, Petar
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Featured articles from other Geoscience Journals
Geochemical and mineralogical fingerprints to distinguish the exploited ferruginous mineralisations of Grotta della Monaca (Calabria, Italy), Dimuccio, L.A.; Rodrigues, N.; Larocca, F.; Pratas, J.; Amado, A.M.; Batista de Carvalho, L.A.
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
See all featured articles from other geoscience journals

Search in KarstBase

Your search for fluid flow (Keyword) returned 58 results for the whole karstbase:
Showing 1 to 15 of 58
Assessing the importance of conduit geometry and physical parameters in karst systems using the storm water management model (SWMM), , Peterson Eric W. , Wicks Carol M. ,
SummaryQuestions about the importance of conduit geometry and about the values of hydraulic parameters in controlling ground-water flow and solute transport through karstic aquifers have remained largely speculative. One goal of this project was to assess the role that the conduit geometry and the hydraulic parameters have on controlling transport dynamics within karstic aquifers. The storm water management model (SWMM) was applied to the Devil's Icebox-Connor's Cave System in central Missouri, USA. Simulations with incremental changes to conduit geometry or hydraulic parameters were performed with the output compared to a calibrated baseline model. Ten percent changes in the length or width of a conduit produced statistically significant different fluid flow responses. The model exhibited minimal sensitivity to slope and infiltration rates; however, slight changes in Manning's roughness coefficient can highly alter the simulated output.Traditionally, the difference in flow dynamics between karstified aquifers and porous media aquifers has led to the idea that modeling of karst aquifers is more difficult and less precise than modeling of porous media aquifers. When evaluated against models for porous media aquifers, SWMM produced results that were as accurate (10% error compared to basecase). In addition, SWMM has the advantage of providing data about local flow. While SWMM may be an appropriate modeling technique for some karstic aquifers, SWMM should not be viewed as a universal solution to modeling karst systems

Fluid flow in the Western Canada sedimentary Basin. 1. Effects of geology, 1969, Hitchon B.

Fluid flow in the Western Canada sedimentary Basin. 1. Effects of topography, 1969, Hitchon B.

Dissolution kinetics of dolomite: effects of lithology and fluid flow velocity., 1985, Herman J. S. , White W. B.

Thermal aspects of the East Midlands aquifer system, 1987, Wilson N. P. , Luheshi M. N. ,
A case study of a heat flow anomaly in the E Midlands of England is reported. The anomaly has been suggested to be an effect of water movement at depth within the E Midlands basin, with recharge to the Lower Carboniferous limestones in their outcrop, eastward movement and ascent of water up a steep faulted anticline at Eakring where the heat flow measurements were made. Numerical modelling of heat and fluid flow has been undertaken for a section running from the Peak District through Eakring to the coast. The results indicate that, although an anomaly is expected for reasonable values of hydrological parameters, its magnitude is less than that observed. The geological structure at Eakring is such that three-dimensional flow is likely to be important, and this could easily account for the discrepancy between the modelling results and the observations. The regional water flow regime has other effects on heat flow, notably the depression of heat flow above the Sherwood Sandstone aquifer

SEDIMENT-HOSTED GOLD MINERALIZATION IN THE RATATOTOK DISTRICT, NORTH SULAWESI, INDONESIA, 1994, Turner S. J. , Flindell P. A. , Hendri D. , Hardjana I. , Lauricella P. F. , Lindsay R. P. , Marpaung B. , White G. P. ,
The Ratatotok district in the Minahasa Regency of North Sulawesi, Indonesia is an area of significant gold mineralisation. Gold has been mined in the district since at least the 1850s, and intensively by the Dutch between 1900 and 1921 with a recorded production of 5,060 kg of gold. Newmont began exploring the district in 1986, and has delineated a major sediment-hosted replacement-style deposit at Mesel, and other smaller deposits in an 8 X 5 km area. A total drill-indicated resource of over 60 metric tonnes of gold ( 2 Moz) is reported for Mesel, and three of the smaller deposits. Approximately 80% of this resource is refractory. Silver grades are usually low (< 10 g/t). The Mesel deposit is similar to many Carlin-type deposits in carbonate hostrocks, alteration, geochemical signature and ore mineralogy, but is distinct in tectonic setting. The discovery of replacement-style mineralisation at Mesel, in an impure limestone within a Tertiary island arc environment, demonstrates that deposits with outward characteristics similar to Carlin-type mineralisation are not restricted to a continental setting. Carbonate sediments in the Ratatotok district were deposited in a Late Miocene restricted basin. Later compressional tectonics caused uplift that resulted in karst development in the limestone and erosion of the adjacent volcanic arc with deposition of a thick epiclastic unit. This was followed by intrusion of shallow level pre-mineral andesite into the sequence. Mineralisation at Mesel, and probably elsewhere in the district, is synchronous with the late-stage reactivation of strike-slip faults. Mineralising fluids at Mesel were focussed along steep structures sympathetic to these faults, and trapped below a relatively impermeable andesite cap rock. Hydrothermal fluids caused decalcification of the silty, more permeable carbonate units with the formation of secondary dolomite, deposition of fine arsenian pyrite, silica veinlets and gold. Volume loss due to decalcification and dolomite formation caused collapse brecciation which enhanced fluid flow and further mineralisation. This locally culminated in total decarbonation and deposition of massive silica. Late-stage stibnite occurs in structural zones within the ore deposit, whereas arsenic (as realgar and orpiment) and mercury (as cinnabar) are concentrated on the periphery. Elsewhere in the Ratatotok district, gold mineralisation is restricted to replacement-style mineralisation in permeable zones along limestone-andesite contacts, open-space-filling quartz-calcite veins and stockworks, and residual quartz-clay breccias. The residual breccias are developed in-situ, and are interpreted to form by dissolution of the wallrock limestone from around pre-existing mineralisation. This has resulted in widespread eluvial gold occurrences

Rock Fractures and Fluid Flow: Contemporary Understanding and Applications, 1996,

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

A governing equation for fluid flow in rough fractures., 1997, Ge S.

Secondary porosity and late diagenetic cements in the Upper Knox Group, central Tennessee region: temporal and spatial history of fluid flow conduit development within the Knox regional aquifer, 1997, Montanez I. P.

Hydrothermal Calcite Veins and the Origin of Caves in the Lower Paleozoic of the Barrandian Basin, Czech Republic: Evidence of Extensive (Post?) Variscan Fluid Flow, 1997, Suchy V. , Zeman A. , Bosak P. , Dobes P. , Hladikova J. , Jackova I.

Fluid flow through carbonate platforms: constraints from 234U/238U and Cl- in Bahamas pore-waters., 1998, Henderson Gideon M.

The initiation of hypogene caves in fractured limestone by rising thermal water: investigation of a parallel series of competing fractures, 1999, Dumont K. A. , Rajaram H. , Budd D. A.
Integrated cave systems can either form at or near the surface of the earth (epigenic) or at some depth below the earth's surface (hypogenic)For caves that form in fractured limestone, the two most common types of cave-system morphologies are branchwork and mazeworkBranchwork caves are composed of tributaries that coalesce in the downstream direction, similar to surface streamsMazework caves exhibit two or more sets of parallel passages intersecting in a grid-like patternThe majority of epigenic caves exhibit branchwork morphologies, which represent the dominance of individual flow pathsIn contrast, mazework caves develop when dissolution occurs along numerous flow pathsWhereas most epigenic caves are related to surficial meteoric flow systems, some mazework caves are thought to have formed in hypogene environments where rising thermal water cools in response to the geothermal gradientOur objective is to examine the fundamental cause for the difference in morphology between epigenic and thermal hypogenic cave systems using numerical modelsIn particular, we are examining the competition between different flow paths in fractured limestone undergoing dissolutional enlargementAs noted in previous numerical studies, epigenic systems are characterized by the dominance of a single flow path, which is consistent with the structure of epigenic cavesSo, in order to explain the structure of maze caves, one has to explain why no single flow path attains dominanceThe retrograde solubility of calcite coupled with heat transfer from the fluid to the rock is hypothesized to provide the mechanism by which dissolutional power is distributed among all competing flow pathsNumerical models of fluid flow, heat transfer, and calcite dissolution chemistry are integrated to develop a model of hypogene cave initiation in fractured limestoneFlow is assumed to occur in the presence of a spatially variable rock temperature field that is constant through timePreliminary numerical modeling results for a system of parallel fractures demonstrate the differences in the nature of competition between flow paths in epigenic (constant temperature) and hypogenic systems (flow in the presence of a negative thermal gradient)Differences in results using various kinetic models for calcite dissolution are also presentedThe role of aperture variation and distribution in a parallel set of fractures is also examined

The surface-subsurface interface and the influence of geologic structure in karst, 1999, Kastning E. H.
Early studies on the development of karst focused principally on surface features (Sweeting, 1973) and dissolutional enlargement in relation to positions of the water table, influence of the lithologic and stratigraphic character of the bedrock, and geologic structureIn recent decades such studies have broadened to include the hydrodynamics of fluid flow through conduits and the geochemical kinetics of dissolution and mass transportThe history of physical speleology has been well documented by several authors (Davies, 1966; Kastning, 1981; LaMoreaux, 1994; LeGrand and Stringfield, 1973; Moore, 1960; Powell, 1975; Shaw, 1992; Sweeting, 1981; White, 1987)Emerging conceptual models of cavern development and subsurficial karst processes, in general, have evolved to include not only the characteristics of groundwater flow within the bedrock, but also the relationship of these systems to inputs and outputs at the surface (zones of recharge and discharge respectively)The general premises of conceptual models of cave and karst processes were proposed by White (1969) and expanded in subsequent revisions (White, 1977; White, this volume)Some recent landmark papers on speleogenesis include those of Ford and Ewers (1978), Palmer (1984,1991), and White (1976)For further information on karst, see the references cited in the Introduction to this volume

Patterns of dissolution porosity in carbonate rocks, 1999, Palmer A. N.
Unlike most geologic processes, the origin of dissolution porosity lends itself readily to analytical solutionsFour salient "laws" govern the process: two mass balances (water balance and chemical mass balance) and two kinetic equations (which describe the dissolution rate and the flow rate of water), and in combination they provide a theoretical basis for quantifying the solutional history of karst aquifersThe greatest difficulty is in applying these clean-cut analytical tools to the complex and rather disordered world of geologyIt is impossible to model a karst aquifer in all its details, because most of the details are unknownHowever, a great deal can be learned about the origin and distribution of dissolution porosity by using the analytical approach to obtain a battery of governing concepts that can be applied to all karst aquifersThis paper summarizes the evolution of a conceptual model whose details were first developed on the basis of field observation and hydraulics, and only later substantiated by chemical kineticsIt applies specifically to carbonate rocks, although the general approach can be modified to fit any geologic setting by substituting the appropriate expressions for kinetics and fluid flow

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