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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. ...

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That alluvial apron is a fan-like plain from the deposition of glacial outwash [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 phreatic zone (Keyword) returned 70 results for the whole karstbase:
Showing 16 to 30 of 70
Estimating subsurface fissure apertures in karst aquifers from equilibrium activities, 1998, Field Ms, Mose Dg,
Rn-222 activities were determined for the karst aquifer underlying Walkersville, Maryland, in an area of ground-water discharge from a single geological unit during the summer and fall seasons, Radon-222 equilibrium activities in karst ground waters can be employed in mass-balance models to estimate microfissure, macrofissure, and conduit aperture dimensions, This approach defines Rn-222 generation and loss in karst aquifers as a function of fissure apertures and the U-238 content of the rock, High Rn-222 activities occur in tight fissures and low Rn-222 activities occur in conduits, In the vadose zone, Rn-222 activities are low as a result of degassing, especially if flow is turbulent and activities are decoupled from the phreatic zone, In the phreatic zone, if recharge to fissures causes a reduction of residence time below that required for equilibrium (approximate to 26 days), Rn-222 activities fall, At springs and in the vadose zone, after a rainfall event, Rn-222 activities increase as waters with long residence and with high Rn-222 activities are expelled from fissure and fracture storage, Field data and selected literature values were used to test the model, Models used to predict median microfissure apertures for this karst aquifer yield aperture estimates ranging from 2.8 mu m to 9.2 mu m. Median macrofissure apertures ranged from 5.53 cm to 5.88 cm, Median conduit apertures ranged from 1.16 m to 1.24 m, Comparison of the models results with published data on karst aquifers and observations at the field site suggest that the predicted apertures are reasonable

Unusual flooding in the Calernakm shaft (Alpes-maritimes, France) Origin and consequences of the phenomen on the deep drainage organisation, 1998, Audra Ph.
The Calernakm shaft is located in the Southern french Alps, near Nice It contains large galleries reaching -478 m deep During unusual high waters, the lower part floods over 100 m height The flooding is linked to a semi-dammed karst structure The galleries organisation proves that the karstification privileges subhorizontal conduits in the epiphreatic zone, without favouring any deep phreatic passages The origin of deep phreatic karsts is discussed

Structure et comportement hydraulique des aquifers karstiques, DSc. Thesis, faculte des Sciences de l'Universite de Neuchatel., 1998, Jeannin Py.
This thesis aims to provide a better knowledge of karst flow systems, from a functional point of view (behaviour with time), as well as from a structural one (behaviour in space). The first part of the thesis deals with the hydrodynamic behaviour of karst systems, and the second part with the geometry of karstic networks, which is a strong conditioning factor for the hydrodynamic behaviour. Many models have been developed in the past for describing the hydrodynamic behaviour of karst hydrogeological systems. They usually aim to provide a tool to extrapolate, in time and/or space, some characteristics of the flow fields, which can only be measured at a few points. Such models often provide a new understanding of the systems, beyond what can be observed directly in the field. Only special field measurements can verify such hypotheses based on numerical models. This is an significant part of this work. For this purpose, two experimental sites have been equipped and measured: Bure site or Milandrine, Ajoie, Switzerland, and Holloch site, Muotathal, Schwyz, Switzerland. These sites gave us this opportunity of simultaneously observe hydrodynamic parameters within the conduit network and, in drillholes, the "low permeability volumes" (LPV) surrounding the conduits. These observations clearly show the existence of a flow circulation across the low permeability volumes. This flow may represent about 50% of the infiltrated water in the Bure test-field. The epikarst appears to play an important role into the allotment of the infiltrated waters: Part of the infiltrated water is stored at the bottom of the epikarst and slowly flows through the low permeability volumes (LPV) contributing to base flow. When infiltration is significant enough the other part of the water exceeds the storage capacity and flows quickly into the conduit network (quick flow). For the phreatic zone, observations and models show that the following scheme is adequate to describe the flow behaviour: a network of high permeability conduits, of tow volume, leading to the spring, is surrounded by a large volume of low permeability fissured rock (LPV), which is hydraulically connected to the conduits. Due to the strong difference in hydraulic conductivity between conduits and LPV, hydraulic heads and their variations in time and space are strongly heterogeneous. This makes the use of piezometric maps in karst very questionable. Flow in LPV can be considered as similar to flow in fractured rocks (laminar flow within joints and joints intersections). At a catchment scale, they can be effectively considered as an equivalent porous media with a hydraulic conductivity of about 10-6 to 10-7 m/s. Flow in conduits is turbulent and loss of head has to be calculated with appropriate formulas, if wanting any quantitative results. Our observations permitted us to determine the turbulent hydraulic conductivity of some simple karst conduits (k',turbulent flow), which ranges from 0.2 to 11 m/s. Examples also show that the structure of the conduit network plays a significant role on the spatial distribution of hydraulic heads. Particularity hydraulic transmissivity of the aquifer varies with respect to hydrological conditions, because of the presence of overflow conduits located within the epiphreatic zone. This makes the relation between head and discharge not quadratic as would be expected from a (too) simple model (with only one single conduit). The model applied to the downstream part of Holloch is a good illustration of this phenomena. The flow velocity strongly varies along the length of karst conduits, as shown by tracer experiments. Also, changes in the conduit cross-section produce changes in the (tow velocity profile. Such heterogeneous flow-field plays a significant role in the shape of the breakthrough curves of tracer experiments. It is empirically demonstrated that conduit enlargements induce retardation of the breakthrough curve. If there are several enlargements one after the other, an increase of the apparent dispersivity will result, although no diffusion with the rock matrix or immobile water is present. This produces a scale effect (increase of the apparent dispersivity with observation scale). Such observations can easily be simulated by deterministic and/or black box models. The structure of karst conduit networks, especially within the phreatic zone, plays an important role not only on the spatial distribution of the hydraulic heads in the conduits themselves, but in the LPV as well. Study of the network geometry is therefore useful for assessing the shape of the flow systems. We further suggest that any hydrogeological study aiming to assess the major characteristics of a flow system should start with a preliminary estimation of the conduit network geometry. Theories and examples presented show that the geometry of karst conduits mainly depends on boundary conditions and the permeability field at the initial stage of the karst genesis. The most significant boundary conditions are: the geometry of the impervious boundaries, infiltration and exfiltration conditions (spring). The initial permeability field is mainly determined by discontinuities (fractures and bedding planes). Today's knowledge allows us to approximate the geometry of a karst network by studying these parameters (impervious boundaries, infiltration, exfiltration, discontinuity field). Analogs and recently developed numerical models help to qualitatively evaluate the sensitivity of the geometry to these parameters. Within the near future, new numerical tools will be developed and will help more closely to address this difficult problem. This development will only be possible if speleological networks can be sufficiently explored and used to calibrate models. Images provided by speleologists to date are and will for a long time be the only data which can adequately portray the conduit networks in karst systems. This is helpful to hydrogeologists. The reason that we present the example of the Lake Thun karst system is that it illustrates the geometry of such conduits networks. Unfortunately, these networks are three-dimensional and their visualisation on paper (2 dimensions) is very restrictive, when compared to more effective 3-D views we can create with computers. As an alternative to deterministic models of speleogenesis, fractal and/or random walk models could be employed.

Overview of Kartchner Caverns, Arizona, 1999, Hill, C. A.
In this paper, the sequence of events for Kartchner Caverns and surrounding region are correlated and traced from the Mississippian Period to the present. Pre-cave events include the deposition of the Escabrosa Limestone during the Mississippian Period and block faulting and hydrothermal activity in the Miocene Epoch. The cave passages formed in the shallow phreatic zone ~ 200 Ka. Vadose events in the cave include the inwashing of pebble gravels and a maximum deposition of travertine during the Sangamon interglacial. Backflooding by undersaturated water caused bevelling of the limestone and travertine. Recent events include the habitation of the cave by vertebrates and invertebrates, and the discovery and development of the cave by humans.

Karst and the evolution of rivers: a case study of Ardennes, 1999, Quinif Y. ,
In karstic areas, tectonic phenomena have two major influences. (i) By uplift, they give potential energy to karst and valley hollowing. (ii) An active tectonic regime is necessary for the development of karstification. The opposition between the development of valleys or karstic networks depends on the type of dissipated energy. Karstic systems in the Ardennes Massif are essentially between 5 and 15 m above the water table for the dry networks, and in the phreatic zone for the active parts. The structuration of the karstic systems is dependent on the uplift of Ardennes and an active tectonic regime is necessary for the genesis of large caves. It is during the Upper and Middle Pleistocene that the Ardennes area underwent tectonic activity; these karstic levels are more than 400 000 years old. (C) Elsevier, Paris

Karst et evolution des rivieres: le cas de l'Ardenne, 1999, Quinif Yves,
In karstic areas, tectonic phenomena have two major influences. (i) By uplift, they give potential energy to karst and valley hollowing. (ii) An active tectonic regime is necessary for the development of karstification. The opposition between the development of valleys or karstic networks depends on the type of dissipated energy. Karstic systems in the Ardennes Massif are essentially between 5 and 15 m above the water table for the dry networks, and in the phreatic zone for the active parts. The structuration of the karstic systems is dependent on the uplift of Ardennes and an active tectonic regime is necessary for the genesis of large caves. It is during the Upper and Middle Pleistocene that the Ardennes area underwent tectonic activity; these karstic levels are more than 400 000 years old.ResumeDans les regions karstiques comprenant des vallees epigenetiques, les phenomenes tectoniques ont deux influences majeures: a) la surrection donne de l'energie potentielle en creant des differences d'altitude, generant a la fois le creusement des vallees et celui du karst; b) une tectonique active est necessaire pour que le processus de karstification debute. L'opposition entre le developpement privilegie soit des vallees, soit des reseaux karstiques depend ainsi du type d'energie dissipee. Les reseaux karstiques de l'Ardenne se situent surtout entre 5 et 15 m au-dessus de la surface piezometrique pour les reseaux secs, et dans la zone saturee pour les parties actives. La structuration de ces reseaux karstiques est favorisee par un ralentissement de la surrection et une activite tectonique. Cette periode se situe dans le Pleistocene moyen et recent, d'apres les datations U/Th de speleothemes

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

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

Le karst haut-alpin du Kanin (Alpes Juliennes, Slovnie-Italie), 2000, Audra, Philippe
Kanin is a high-alpine karst located in the Italo-slovenian Julian Alps. Its surface was elaborated by the quaternary glaciers and includes some inherited discreet tertiary morphological features. Recent dye tracing has shown that the structural setting permits water infiltrated in Italian catchments to contribute to Slovene springs. Hydrodynamic and physico-chemical water analyses show extremely quick transfers of water during snow melt or heavy storms; these create spectacular overflows, such as the Boka spring which emerges as a 100 m high waterfall. The phreatic zone, linked to the impermeable dam of the So_a valley, does not significantly slow these transfers. Nevertheless, it contributes to the occurrence of low water levels during recession periods, giving highly mineralised water after long resident periods. The presence of very deep and developed karst systems is explained by the combination of advantageous factors: thick and jointed limestone, important height gradient, and considerable precipitation. Paleomagnetic dating in one of the largest systems (_rnelsko brezno) attributes some glacial sediments to the Lower Pleistocene period. Their configuration seems to show that this karst system is pre-quaternary.

Plio-Quaternary karst development in the French Prealps: Speleogenesis and significance of cave fills, 2000, Audra P.
Three French cave systems in the Prealps in the Vercors and Devoluy mountain areas are described. It is possible to reconstruct their evolution by analyzing their morphology and by dating the karst fill using paleomagnetism and U/Th. Cave development began at the end of the Miocene during uplift when inclined tubes formed in the epiphreatic zone. Later the tubes were partially blocked by weathered detritus from the surface. Uplift diverted former recharge away from the caves and extensive calcite deposition occurred. The cave systems were reactivated during glaciations, with flooding to considerable depths. The epiphreatic zone was blocked with calcareous varves from meltwater. During interglacial periods, either calcite deposition or dissolution occurred, depending on the altitude and density of the soil cover.

Genesis of a large cave system: the case study of the North of Lake Thun system (Canton Bern, Switzerland), 2000, Jeannin Py. , Bitterli T. , Hauselmann P.
The genesis of the cave system in the region Hohgant-Sieben Hengste-Lake of Thun (more than 250 km of surveyed passage) has been reconstructed based on speleomorphological observations (mainly by observing where the morphology changes from vadose to phreatic). Eight flow systems (phases) and their respective conduit networks have been distinguished so far. The oldest had a phreatic level at an altitude of 1950 m a.s.l. The last corresponds to today's phreatic zone located at 658 m a.s.l. Between each system, the water table dropped several hundred meters. This appears to be a consequence of changes in boundary conditions, mainly the springis position, which moved down as a tectonic uplift and deepening of the nearby valleys occured. Observations demonstrate that phreatic conduits are sometimes developed close to the ancient water table, but often much deeper, down to 200 to 400 m below this level. The change from one phase to the next seems to have been quick. This stepwise evolution is compatible with the results of computer models which give durations of 10'000 to 30i000 years for conduits systems to develop. Analysis of the conduit networks of each flow system shows that their geometry is mainly influenced by the hydraulic gradients and the overall geometry of the aquifer. The orientation of discontinuity surfaces (fractures and bedding planes) and/or their intersections, play a subordinate role. This is also supported by numerical models found in the literature. As, despite a high fracture density, we observe deep rather than shallow phreatic loops, we assume that the heterogeneity of the discontinuity openings plays a more important role in the depth of karstification than the frequency of the discontinuities.

Solutional and erosional morphology, 2000, Lauritzen Se. , Lundberg J.
Caves are produced through the action of speleogenetic agents acting under various constraints to produce speleogenetic facies. These facies, expressed at the meso- and micro-scale, reflect the major and minor speleogenetic agents that operated on that cave; they also reflect the history of the cave, both during speleogenesis proper and during the post-speleogenetic phase, in particular the most recent history. Geological control is evident through the association of caves with guiding voids (the singularities that govern permeability) and passage shape with rock chemistry (solubility). Hydrological control guides the locus and direction of dissolution; phreatic conditions support omnidirectional dissolution and thus hydraulically controlled tubular forms, while vadose conditions allow only unidirectional dissolution and thus gravity-controlled canyon forms and karren-like features. Of the micro-forms, scallops are specific flow indicators that yield both directional and quantitative information like flow rates and various hydraulic parameters specific to the cave passages. The presence of a sediment fill may further direct corrosion; in the phreatic zone this causes paragenesis; in the vadose zone, sediments cause lateral undercutting and eventually collapse. Vadose streams display many of the forms of surface streams, such as migrating meanders, entrenchment, rock-mill pot-holes, and waterfalls. Vadose shafts, dome-pits and condensation-corrosional forms are perhaps specific to the cave enviroment. The various vadose, phreatic and certain water-table-specific forms are, in combination, powerful methods for reconstructing phases of speleogenesis as well as external base levels. Combined with speleothem dating techniques, they become important methods for determining erosion rates and landscape evolution.

Les stalagmites d'argile, indicateurs de mises en charge, 2001, Audra Ph.
Detailed morphological description and growing processes linked to backflooding in the epiphreatic zone. These are climatic records, particularly concerning rare floodings.

Inverse modeling of the hydrological and the hydrochemical behavior of hydrosystems: Characterization of karst system functioning, 2001, Pinault J. L. , Plagnes V. , Aquilina L. , Bakalowicz M. ,
Inverse modeling of mass transfer characterizes the dynamic processes affecting the function of karst systems and can be used to identify karst properties. An inverse model is proposed to calculate unit hydrographs as well as impulse response of fluxes from rainfall-runoff or rainfall-flux data, the purpose of which is hydrograph separation. Contrary to what hydrologists have been doing for years, hydrograph separation is carried out by using transfer functions in their entirety, which enables accurate separation of fluxes, as was explained in the companion paper [Pinault et al., this issue]. The unit hydrograph as well as impulse response of fluxes is decomposed into a quick and a slow component, and, consequently, the effective rainfall is decomposed into two parts, one contributing to the quick flow (or flux) and the other contributing to the slow flow generation. This approach is applied to seven French karstic aquifers located on the Larzac plateau in the Grands Causses area (in the south of France). Both hydrodynamical and hydrogeochemical data have been recorded from these springs over several hydrological cycles. For modeling purposes, karst properties can be represented by the impulse responses of flow and flux of dissolved species. The heterogeneity of aquifers is translated to time-modulated flow and transport at the outlet. Monitoring these fluxes enables the evaluation of slow and quick components in the hydrograph. The quick component refers to the 'flush flow' effect and results from fast infiltration in the karst conduit network when connection is established between the infiltration and phreatic zones, inducing an increase in water head. This component reflects flood events where flow behavior is nonlinear and is described by a very short transfer function, which increases and decreases according to water head. The slow component consists of slow and fast infiltration, underground runoff, storage in annex-to-drain systems, and discharge from the saturated zone. These components can be further subdivided by measuring chemical responses at the karst outlet. Using Such natural tracers enables the slow component of the unit hydrograph to be separated into preevent water, i.e., water of the reservoir and event water, i.e., water whose origin can be related to a particular rainfall event. These measurements can be used to determine the rate of water renewal. Since the preevent water hydrograph is produced by stored water when pushed by a rainfall event and the event water hydrograph reflects rainwater transfer, separating the two components can yield insights into the characteristics of karst aquifers, the modes of infiltration, and the mechanisms involved in karstification, as well as the degree of organization of the aquifer

Palaeo-mixing zone karst features from Palaeocene carbonates of north Spain: criteria for recognizing a potentially widespread but rarely documented diagenetic system, 2001, Bacetaa J. I. , Wrightb V. P. , Pujalte V.

Marine-meteoric mixing zone dissolution effects are a major feature of present day karst systems in carbonate platforms,yet are rarely reported in the geological record. An example is described from the upper Danian platform limestones of the Alava province,in  the western Pyrenees,north Spain. This consists of several narrow zones with sponge-like porosity analogous to the "Swiss-cheese" features found in present day mixing  zones. These zones are stained by Fe-oxides and overlie limestones which are irregularly  dolomitized  and contain disseminated pyrite. These high-porosity  zones are interpreted as having developed in marine mixing zones where mixing corrosion and microbially  mediated processes increased dissolution. If collapsed,ancient mixing zones could be misinterpreted as "terra-rossa" palaeosols. The main criteria to identify them as mixing zone products are their occurrence below a palaeo-meteoric phreatic zone,their association with stratified oxic and anoxic redox zones and petrographic evidence for highly variable calcite saturation states.

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