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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 cave flower is an elongate curved deposit of gypsum or epsomite on a cave wall in which growth occurs at the attached end [10]. synonyms: gypsum flower; oulopholite. see also anthodite; cave cotton.?

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 karst modeling (Keyword) returned 38 results for the whole karstbase:
Showing 16 to 30 of 38
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

Toward understanding transport in the Floridan karst, 1999, Loper D.
There is a strong need for better scientific knowledge of groundwater behavior in Floridan-type karstic aquifers and for better mechanisms to transfer such knowledge into practiceTo facilitate this transfer, a new scientific organization called the Hydrogeology Consortium has recently been establishedThe Consortium is described in detail elsewhere in this volumeIts mission is to cooperatively provide scientific knowledge applicable to groundwater resource management and protectionA necessary adjunct to the mission of the Consortium is the development of better models of transport and dispersion in karstic aquifersA first step in this development is elucidation of the shortcomings of the standard model of dispersionIn this model, dispersion is represented by an effective diffusivity, called the dispersion coefficient, which is the product of the mean flow speed and the decorrelation distanceIt is shown that this model does not correctly describe dispersion in an aquifer having porosity that is weakly correlated on a large scaleThat is, the concept of a decorrelation distance is not viable for a non-homogeneous aquiferOne approach toward the quantification of transport and dispersion in karstic aquifers to model the aquifer as a classic Darcian porous medium riddled by a distribution of macroscopic conduitsThe flow properties of this model are compatible with the standard Darcian model, but its transport equation is non-autonomous; it has coefficients that depend on the elapsed time

Origin and attributes of paleocave carbonate reservoirs, 1999, Loucks R. G.
Paleocave systems form an important class of carbonate reservoirs that are products of near-surface karst processes and later burial compaction and diagenesisOrigins of fractures, breccias, sediment fills and other features associated with paleocave reservoirs have been studied in modem and ancient cave systemsInformation about such cave systems can be used to reconstruct the general evolution of paleocave reservoirs and understand their associated scale, pore networks, and spatial complexities

Temperature as a natural tracer of short residence times for groundwater in karst aquifers, 1999, Martin J. B. , Dean R. W.
Chemistry of karst waters is controlled by reactions with aquifer rocks, the extent of mixing between water sources, and variations in the composition of recharged waterThe extent of reactions and mixing may be determined uniquely if compositions of both recharged and discharged water are known, such as where sinking streams are linked to resurgent springs, and if residence time in the subsurface can be measuredSuch a linked system occurs along the Santa Fe River in north-central Florida, where the river flows underground for approximately 52 km as it crosses from confined to unconfined portions of the Floridan AquiferTemporal variations in temperature can be correlated between the river sink, the river rise, and Sweetwater Lake, a karst window approximately midway between the sink and riseDelays in the arrival time of temperature maxima and minima from the sink to Sweetwater Lake and from Sweetwater Lake to the Rise reflect the residence time of the river water in the subsurfaceResidence time correlates with the river stage and ranges from approximately 12 hours to more than four days at high and low stage, respectively between the river sink and SweetwaterLake, and from about six hours to nearly two days at high and low stage, respectively, between Sweetwater Lake and the river riseThese short residence times reflect minimum flow rates of between 13 and 9 km/day, indicating conduit flowKnowing the residence time at any stage allows sampling of water as it enters the aquifer, and then again as it dischargesChanges in the chemistry of water as it passes through the subsurface should reflect chemical reactions, mixing, or both

The development of basin-scale conceptual models of the active-flow conduit system, 1999, Meiman J. , Ryan M. T.

A conceptual view of carbonate island karst, 1999, Mylroie J. E. , Vacher H. L.
Conceptually, the karst of carbonate islands can be modeled as the result of eogenetic diagenesis, freshwater/ saltwater mixing, and glacioeustasyThe resulting eogenetic karst occurs in small, youthful limestone islands where the evolution of the karst is concurrent with meteoric diagenesis of the host rock, which has never been out of the active circulation of meteoric waterThe rearrangement of the material of high porosity / low permeability sediments into moderate porosity / high permeability rock feeds back to the nature of the diagenetic environment as the flow volume of the lens is reduced by increasing flow efficiencyLimestone islands are a constrained and simple environment, defined as carbonate islands (no noncarbonate rock) and composite islands (mixture of carbonate and non carbonate rock)Simple carbonate islands lack noncarbonate rocks within the active hydrological zone; carbonate-cover islands contain a noncarbonate contact that limits the freshwater lens and deflects vadose flowThe type of island greatly influences the subsequent karst hydrologyIncreasing island size appears to cross a threshold favoring conduit flowThe karst features resulting from these island types, combined with mixing geochemistry and glacioeustasy, differ from those in continental settings and require a unique conceptual approach to modeling

Anisotropy in carbonate aquifers,, 1999, Palmer A. N

A statistical evaluation of the structural influence on solution-conduit patterns, 1999, Palmer A. N.
Geologic mapping of accessible vadose and phreatic cave passages in a variety of carbonate aquifer types has quantified the relation between conduit trends and the local stratal dipGravitational flow in the vadose zone tends to follow the dip of the strata, with varied degrees of downward discordance across the strata according to the distribution of cross-cutting fracturesThis trend is strongest in prominently bedded strata of low dipLikewise there is a distinct tendency for phreatic flow to follow paths nearly parallel to the local strikeThis pattern is most favored in bedded rocks of all types, especially those of high dipHowever, in prominently fractured strata the dip orientation of vadose channels is faint, and there is no significant preference for strike orientation of phreatic conduitsThe data and interpretive methods described in this report pertain only to unconfined karst aquifers, and only to major flow paths that are capable of forming discrete solution conduits

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

Potential influence of aperture variability on the dissolutional enlargement of fissures, 1999, Rajaram H. , Cheung W. , Hanna B.

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

Subsidiary conduit systems: A hiatus in aquifer monitoring and modeling, 1999, Smart C. C.

Delineation of source-protection zones for carbonate springs in the Bear River Range, northeastern Utah, 1999, Spangler L. E.

Linear systems approach to modeling groundwater flow and solute transport through karstic basins, 1999, Wicks C. M. , Hoke J. A.
Modeling groundwater flow and solute transport in karst aquifers is complicated by the highly heterogeneous nature of the aquiferA linear systems approach provides a basin-scale perspective that does not require specific details of internal geometryIn this study, three kernel functions were derived: one that relates excess recharge to spring discharge; one that relates solute input from a point source to concentrations of the solute in the spring discharge; and one that relates input from a non-point source to concentrations of solute in the spring waterResults indicate that these kernel functions can be used to predict groundwater flow and solute transport through a large karstic basin

A comprehensive strategy for understanding flow in carbonate aquifers, 1999, Worthington S. R. H.

Studies of carbonate aquifers usually either concentrate on sampling the channel flow (egsink-to-spring tracer testing, spring monitoring) or on sampling the non-channel flow (egborehole measurements)A comprehensive approach is advocated here, involving the integration of both sources of information, as well as measurements of the porosity and permeability of the unfractured rockRepresentative sampling can be achieved by treating carbonates as triple-porosity aquifers, with one-, two-, and three-dimensional porosity elementsThe division of carbonate aquifers into "karstic" or "non-karstic" types is unwarranted


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