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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. ...

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That contributing region is that region which contributes to well discharge in inclined water-table flow [16].?

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Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
See all featured articles
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;
See all featured articles from other geoscience journals

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Your search for karst modeling (Keyword) returned 38 results for the whole karstbase:
Showing 1 to 15 of 38
Karst modeling and 'desktop geology', 1999, Palmer A. N. ,

On predicting contaminant transport in carbonate terrains: Behavior and prediction, 1999, Annable W. K , Sudicky E. A.
A three-dimensional numerical model was used to quantify the fate of conservative transport in carbonate terrainsNumerical flow and transport experiments were conducted in proto-conduit scale limestone terrains (conduits less than 10cm) which determined that a priori information on the 'spill' and/or 'tracer injection location' and discharge locations provided little insight in characterizing the complexity of the internal labyrinth of interconnected conduitsScaling, aside from the characterization of the geologic media, was one of the most limiting factors in quantifying recharge tracers or contaminant distributionHowever, if sufficient numbers of discharge locations (springs) are known, the extent of downstream contaminant migration can be characterized

Solutionally enhanced leakage rates of dams in karst regions, 1999, Bauer S. , Birk S. , Liedl R. , Sauter M.
This paper presents numerical model studies regarding the development of leakage rates of dams in karst regions due to solutional enlargement of conduits in the rock beneath the reservoirA hybrid continuum-discrete flow model (CAVE) is used for the modelingThe fractured carbonate rock beneath the reservoir is represented by a network of initial conduitsThe effects of a preferential flowpath and a grout curtain on leakage rates are studied in different scenariosFor the parameters considered in this paper, the simulation results suggest that dissolutional widening of the network leads in all scenarios to leakage rates endangering the reservoir within 100 years

Entranceless and fractal caves revisited, 1999, Curl R. L.
Cave geometric properties have been studied between 1958 and today as statistical or fractal objectsThese studies have divulged some degree of order in such properties as the distribution of cave lengths in a region and the distribution of cave passage sizes, and exhibiting some degree of self-similarity, suggesting a fractal nature, or moderate departures from self-similarity, suggesting geological mechanisms that introduce particular scalesThe studies have also produced methods for estimating roughly the number of entranceless caves and the length distribution of all caves in regions, and the volume of caves as a function of the size of cave passages, first steps in a more complete description of karst aquifers

Dynamics of the early evolution of karst, 1999, Dreybrodt W. , Gabrovsek F. , Siemers J

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

Quantitative analysis of tracer breakthrough curves from tracing tests in karst aquifers, 1999, Field M. S.
Numerical analysis of tracer-breakthrough curves allow quick reliable estimates for many of the basic hydraulic and geometric parametersTracer-breakthrough curve analysis relies on the application of a continuous mass balance model for transport parameter estimationReadily obtained hydraulic parameters required for modeling include peak arrival time and peak velocity, longitudinal dispersion, and Peclet numberGeometric parameters include volume, cross-sectional area, and diameterSome boundary-layer effects can also be roughly estimated

Bench-scale karst models, 1999, Florea L. J. , Wicks C. M.

Perspectives in karst hydrogeology and cavern genesis, 1999, Ford D. C.
Hydrogeology and speleology both began during the 19th CenturyTheir approaches to limestone aquifers diverged because hydrogeologists tend to measure phenomena at very local scales between drilled wells and generalize from them to basin scales, while speleologists study the large but sparse conduits and then infer conditions around themConvergence of the two approaches with modem computing should yield important genetic models of aquifer and caveGenesis of common cave systems by dissolution is a three-dimensional problem, best broken down into two-dimensional pairs for purposes of analysisHistorically, the dimensions of length and depth have received most attention, especially the question of the location of principal cave genesis with respect to the water tableBetween 1900 and 1950, different scientists proposed that caves develop principally (1) in the vadose zone; (2) at random depth in the phreatic zone; (3) along the water table in betweenEmpirical evidence suggests that these differing hypotheses can be reconciled by a four-state model in which the frequency of penetrable fissuration controls the system geometryFor the dimensions of length and breadth (plan patterns) there is widespread agreement that dendritic (or branchwork) patterns predominate in common cavesIrregular networks or anastomose patterns may occur as subsidiary componentsWhen hydraulic conditions in a fissure are anisotropic (the usual case), dissolutional conduit development is competitive: local hydraulic gradients are reoriented toward the first conduits to break through to outlet points, redirecting others toward them in a cascading processPlan patterns are most complex where there have been multiple phases ("levels") of development in a cave system in response to such effects as river channel entrenchment lowering the elevation of springs

Bridging the gap between real and mathematically simulated karst aquifers, 1999, Groves C. , Meiman J. , Howard A. D.
Although several numerical codes have been developed to study the patterns of karst aquifer evolution and behavior, in the current generation of models simplifying assumptions must be made because of incomplete quantitative understanding of key processesA one-year, high-temporal-resolution study of carbonate chemistry with Mammoth Cave's Logsdon River, designed to investigate details of these processes, reveals that limestone dissolution rates vary appreciably over storm and seasonal time scales due to variations in the flux of CO2-rich waters that wash through, and flood, conduits during storm eventsThis undersaturated storm water dissolves rock within a flood zone 25-30 m thickThrough the year, waters were undersaturated only 31% of the timeTime scales of actual karst development may thus be impacted by time-varying processes different from the constant-input chemistry assumed in current published numerical codesA dual approach, coupling quantitative modeling and refinement of the models by careful measurement of processes within real karst aquifers, provides a framework for developing a comprehensive understanding of karst system behavior

Interpreting flow using permeability at multiple scales, 1999, Halihan T. , Sharp Jr. J. M. , Mace R. E.
Two difficulties that karst aquifers can present are permeability that varies with the scale of measurement (up to nine orders of magnitude), and permeability that is so high that standard pump tests obtain no measurable drawdownThough it is difficult to quantify, permeability is the most sensitive parameter for either laminar or turbulent groundwater equations and must be accurately estimatedPermeability data at the small-scale (laboratory and outcrop) were used to reproduce permeabilities measured at the well- and regional-scales in the San Antonio segment of the Edwards aquiferThese calculations provided an understanding of how features observed at the small-scale affect permeability measurements at larger scalesConversely, these calculations can be performed on the well- and regional-scale to estimate what small-scale features are influencing the aquiferIn this paper, equations and techniques are presented to help answer questions such as: (1) How can small-scale data be combined to determine an effective well- or regional-scale permeability? (2) What size high-permeability features are influencing an aquifer on the well- or regional-scale? (3) Is the flow in an aquifer Darcian? (4) What velocities should be expected in an aquifer?

Karstic permeability: organized flow pathways created by circulation, 1999, Huntoon P. W.
Most karstic permeability in soluble rocks is created by the circulation of a solvent through the rockGiven a bit of geologic time, karstic permeability develops a hierarchal structure of highly organized conduits that facilitates the movement of the fluid in the downgradient directionConsequently, karst permeability is not an independent, inherited static attribute of the rock; rather it adjusts dynamically to changing boundary conditions in the flow systemKarstic permeability tends to be the most anisotropic of all the permeability types found in natureThe permeabilities of the dissolution channels generally overwhelm the transmissive characteristics of all the other types of permeability presentConsequently, when dealing with assessments of the impacts of withdrawals or the migration of contaminants in carbonate aquifers, the professional is obligated to find and unravel the character of the organized conduit network; otherwise the essence of the transmissive and storage properties of the flow regime is inadequately formulated, so predictive failures are inevitable

Variation of karstic permeability between unconfined and confined aquifers, Grand Canyon region, Arizona, 1999, Huntoon Pw. .
Most of the ground water in the Grand Canyon region circulates to springs in the canyon through the thick, deeply buried, karstified Cambrian through Mississippian carbonate sectionThese rocks are collectively called the lower Paleozoic carbonates and comprise the Redwall-Muav aquifer where saturatedThe morphologies of the caves are primarily a function of whether the carbonates are unconfined or confined, a distinction that has broad significance for groundwater exploration and which appears to be generally transferable to other carbonate regionsCaves in unconfined high-gradient environments tend to be highly localized, partially saturated, simple tubes, whereas those in confined low-gradient settings are saturated 2- or even 3-dimensional mazesThe highly heterogeneous distribution of the unconfined conduits makes for difficult drilling targets, whereas the more ubiquitously distributed confined mazes are far easier to targetThe distinctions between the storage characteristics within the two classes is probably even more importantThere is minimal groundwater storage in the unconfined systems because they are well drainedIn contrast, the saturated mazes exhibit maximal storageConsequently, system responses to major storm recharge events in the unconfined systems is often dominated by flow-through rather than the pulse-through hydraulics as found in the confined systemsSpring discharges from the unconfined systems tends to be both flashy and highly variable from season to season, but total dissolved solids are smallIn contrast, the pulse-through hydraulics in the artesian systems causes spring discharge responses to be highly moderated and, in the larger basins, remarkably steadyBoth total dissolved solids and temperatures in the waters from the confined aquifers tend to be elevated because most of the water is derived from storageKarst permeability is created by the flow system, consequently predicting where the permeability is best developed in a carbonate section involves determining how circulation should be ideally organized through an examination of the geometry of the flow systemThe areas where flow concentrates are the areas where karstification will maximize, provided enough time has elapsed to allow dissolution to adjust to the imposed boundary conditionsThe rate of adjustment in the Grand Canyon region appears to be related to the degree of saturationThe artesian systems are far better adjusted to hydraulic gradients than the unconfined systems, a finding that probably implies that there is greater contact between the solvent and rock in the saturated confined systems

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

From a conceptual model of karst hydrological systems to water-vulnerability mapping, 1999, Jeannin Py. , Zwahlen F. , Doerfliger N.
A conceptual model of karst hydrological systems is presented hereIt considers that water flows through four cascading subsystems: soils, epikarst, unsaturated zone, and saturated zoneThis model lead us to define four criteria which appear to be significant for intrinsic vulnerability assessment with respect to a spring or a well: characteristics of epikarst (E), characteristics of protective cover (P), recharge or infiltration type (I) and presence/absence of a well-developed conduit network (K)The method has proved to be adequate for karst in Central EuropeIn the future, it should be tested in other areas and compared to numerical approaches of karst systems

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