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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 column is 1. a subsurface dripstone formation produced by the union of a stalactite and a stalagmite in a cave [20]. 2. a flowstone formation, generally cylindrical, formed by the union of a stalactite and stalagmite [10]. not to be confused with pillar. synonyms: (french.) colonne, pillier stalamitique; (german.) tropfstein-saule; (greek.) stalaktitike stele; (italian.) colonna (stalagmitica o stalattitica) (russian.) kolona; (spanish.) columna; (turkish.) sutun; (yugoslavian.) stup, steber, stolpic. see also pillar.?

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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 release (Keyword) returned 79 results for the whole karstbase:
Showing 16 to 30 of 79
Geochemistry of Fluorite and Related Features of the Kugitangtou Ridge Caves, Turkmenistan, 1998, Maltsev, V. , Korshunov, V.
This paper presents a model explaining the fluorine geochemistry in the Cupp-Coutunn Cave System, in the Kugitangtou Ridge, southeastern Turkmenistan. By the corrosive activity of biologically derived sulfuric acid, HF gas is released by weathering of fluorite in residual cave deposits and in speleothems formed during a period of thermal activity. Secondary fluorite is produced, and conditions are provided for silica and aluminum mobility in the caves. The latter process helps to explain the origin of the clay mineral sauconite, Zn3(Si4O10)(OH)2nH2O, and fraipontite, (Zn,Al)3(SiAl)2O5(OH)4, a member of the kaolinite-serpentine group.

Mapping groundwater vulnerability: the Irish perspective, 1998, Daly D, Warren Wp,
The groundwater protection scheme used in the Republic of Ireland since the 1980s had not encompassed the vulnerability mapping concept. Yet internationally, vulnerability maps were becoming an essential part of groundwater protection schemes and a valuable tool in environmental management. Consequently, following a review of protection schemes world-wide, the scheme used in Ireland was updated and amended to include vulnerability maps as a crucial component of the scheme. The approach taken to vulnerability assessments and mapping in the Republic of Ireland has been dictated by the following fundamental questions: Vulnerability of what? Vulnerability to what? Which factors determine the degree of vulnerability? What is the appropriate scale for map production? How can limitations and uncertainties be taken into account? How can vulnerability assessments be integrated into environmental and resource management? The following decisions were made: (i) we should map the vulnerability of groundwater, not aquifers or wells/springs; (ii) the position in the groundwater system specified to be of interest is the water-table (i.e. first groundwater encountered) in either sand/gravel aquifers or in bedrock; (iii) we should map the vulnerability of groundwater to contaminants generated by human activities (natural impacts are a separate issue); (iv) as the main threat to groundwater in Ireland is posed by point sources, we should map the vulnerability of groundwater to contaminants released at 1-2 m below the ground surface; (v) the characteristics of individual contaminants should not be taken into account; (vi) the natural geological and hydrogeological factors that determine vulnerability are the sub-soils above the watertable, the recharge type (whether point or diffuse) and, in sand/gravels, the thickness of the unsaturated zone; (vii) based on these factors, four vulnerability categories are used (extreme, high, moderate and low); (viii) map scales of 1:50 000 and 1:10 000 are preferred; (ix) limitations and uncertainties are indicated by appropriate wording on the maps and a disclaimer; (x) vulnerability maps should be incorporated into groundwater protection schemes, which should be used in decision-making on the location and control of potentially polluting developments. Vulnerability maps have now been produced for a number of local authority areas. They are an important part of county groundwater protection schemes as they provide a measure of the likelihood of contamination, assist in ensuring that protection schemes are not unnecessarily restrictive of human economic activity, help in the choice of engineering preventative measures, and enable major developments, which have a significant potential to contaminate, to be located in areas of relatively low vulnerability and therefore of relatively low risk, from a groundwater perspective

Mapping Chicxulub crater structure with gravity and seismic reflection data, 1998, Hildebrand A. R. , Pilkington M. , Ortizaleman C. , Chavez R. E. , Urrutiafucugauchi J. , Connors M. , Granielcastro E. , Camarazi A. , Halpenny J. F. , Niehaus D. ,
Aside from its significance in establishing the impact-mass extinction paradigm, the Chicxulub crater will probably come to exemplify the structure of large complex craters. Much of Chicxulub's structure may be mapped' by tying its gravity expression to seismic-reflection profiles revealing an [~]180 km diameter for the now-buried crater. The distribution of karst topography aids in outlining the peripheral crater structure as also revealed by the horizontal gradient of the gravity anomaly. The fracturing inferred to control groundwater flow is apparently related to subsidence of the crater fill. Modelling the crater's gravity expression based on a schematic structural model reveals that the crater fill is also responsible for the majority of the negative anomaly. The crater's melt sheet and central structural uplift are the other significant contributors to its gravity expression. The Chicxulub impact released [~]1.2 x 1031 ergs based on the observed collapsed disruption cavity of [~]86 km diameter reconstructed to an apparent disruption cavity (Dad) of [~]94 km diameter (equivalent to the excavation cavity) and an apparent transient cavity (Dat) of [~]80 km diameter. This impact energy, together with the observed [~]2 x 1011 g global Ir fluence in the Cretaceous-Tertiary (K-T) fireball layer indicates that the impactor was a comet estimated as massing [~]1.8 x 1018 g of [~]16.5 km diameter assuming a 0.6 gcm-3 density. Dust-induced darkness and cold, wind, giant waves, thermal pulses from the impact fireball and re-entering ejecta, acid rain, ozone-layer depletion, cooling from stratospheric aerosols, H2O greenhouse, CO2 greenhouse, poisons and mutagens, and oscillatory climate have been proposed as deleterious environmental effects of the Chicxulub impact with durations ranging from a few minutes to a million years. This succession of effects defines a temperature curve that is characteristic of large impacts. Although some patterns may be recognized in the K-T extinctions, and the survivorship rules changed across the boundary, relating specific environmental effects to species' extinctions is not yet possible. Geochemical records across the boundary support the occurrence a prompt thermal pulse, acid rain and a [~]5000 year-long greenhouse. The period of extinctions seems to extend into the earliest Tertiary

Oxidation of organic matter in a karstic hydrologic unit supplied through stream sinks (Loiret, France), 1998, Alberic P, Lepiller M,
The aim of this paper is to appraise the ability of the oxidation of riverine organic matter in the control of limestone dissolution, in a karst network. Biogeochemical processes during infiltration of river water into an alluvial aquifer have already been described for an average flow velocity of 4-5 m d(-1) (Jacobs, L. A., von Gunten, H. R., Keil, R, and Kuslys, M. (1988) Geochemical changes along a river-groundwater infiltration flow path: Glattfelden, Switzerland. Geochim. Cosmochim. Acta 52, 2693-2706; Von Gunten, H. R., Karametaxas, G., Krahenbuhl, U., Kuslys, M., Giovanoli R., Hoehn E. and Keil R. (1991) Seasonal biogeochemical cycles in riverborne groundwater. Geochim. Cosmochim. Acta 55, 3597-3609; Bourg, A. C. M. and Bertin, C. (1993) Quantitative appraisal of biogeochemical chemical processes during the infiltration of river water into an alluvial aquifer. Environ. Sci. Technol. 27, 661-666). Karstic drainage networks, such as in the River Loire-Val d'Orleans hydrologic system (Fig. 1), make possible flow velocities up to 200 m h(-1 a) and provide convenient access to different water samples several tens of km apart, at both extremities of the hydrologic unit (Chery, J.-L. (1983) Etude hydrochimique d'un aquifere karstique alimente par perte de cours d'eau (la Loire): Le systeme des calcaires de Beauce sous le val d'Orleans. These, Universite d'Orleans; Livrozet, E. (1984) Influence des apports de la Loire sur la qualite bacteriologique et chimique de l'aquifere karstique du val d'Orleans. These, Universite d'Orleans). Recharge of the karstic aquifer occurs principally from influent waters from stream sinks, either through coarse alluvial deposits or directly from outcrops of the regional limestone bedrock (Calcaires de Beauce). Recharge by seepage waters From the local catchment basin is small (Zunino, C., Bonnet, M. and Lelong, F. (1980) Le Val d'Orleans: un exemple d'aquifere a alimentation laterale. C. R. somm. Soc. Geol. Fr. 5, 195-199; Gonzalez R. (1992) Etude de l'organisation et evaluation des echanges entre la Loire moyenne et l'aquifere des calcaires de Beauce. These, Universite d'Orleans) and negligible in summer. This karstic hydrologic: system is the largest in France in terms of flow (tens to hundreds of m(3)/s) and provides the main water resource of the city of Orleans. Chemical compositions of influent waters (River Loire) and effluent waters (spring of the river Loiret) were compared, in particular during floods in summer 1992 and 1993 (Figs 2-4). Variation of chloride in the River Loire during the stream rise can be used as an environmental tracer of the underground flow (Fig. 2). Short transit times of about 3 days are detectable (Fig, 2) which are consistent with earlier estimations obtained with chemical tracers (Ref. in Chery, J.-L. (1983) These, Universite d'Orleans). Depending on the hydrological regime of the river, organic carbon discharge ranges between 3-7 and 2-13 mg/l for dissolved and particulate matter respectively (Fig. 3). Eutrophic characteristics and high algal biomasses are found in the River Loire during low water (Lair, N. and Sargos, D. (1993) A 10 year study at four sites of the middle course of the River Loire. I - Patterns of change in hydrological, physical and chemical variables in relation to algal biomass. Hudroecol. Appl. 5, 1-27) together with more organic carbon rich suspended particulate matter than during floods (30-40 C-org % dry weight versus 5-10%). Amounts of total organic carbon and dissolved oxygen (Fig. 3) dramatically decrease during the underground transport, whereas conversely, dissolved calcium, alkalinity and inorganic carbon increase (Fig. 4). Anoxia of outflows map start in April. Dissolution of calcium carbonates along the influent path outweighs closed system calcite equilibrium of inflow river waters (Table 3). The impact of organic matter oxidation on calcite dissolution may be traced by variations of alkalinity and total carbonates in water. Following, Jacobs, L. A., von Gunten, H. R., Keil, R. and Kuslys, M. (1988) Geochemical changes along a river-groundwater infiltration flow path: Glattfelden, Switzerland. Geochim. Cosmochim. Acta 52, 2693-2706), results are shown graphically (Fig. 5). Extent of reactions is controlled by the consumption of dissolved O-2 and nitrate for organic matter oxidation and by the release of Ca2 for calcite dissolution (Table 2). The karstic network is considered to behave like a biological reactor not exchanging with the atmosphere, with steady inhabitant microbial communities (Mariotti A., Landreau A, and Simon B. (1988) N-15 isotope biogeochemisrry and natural denitrification process in groundwater: Application to the chalk aquifer of northern France. Geochim. Cosmochim. Acta 52, 1869-1878; Gounot, A.-M. (1991) Ecologie microbienne des eaux ei des sediments souterrains. Hydrogeologie, 239-248). Thus, energy requirements only are considered, not carbon assimilation. Moreover, there is no necessity to invoke any delay for nitrification enhancement, as observed elsewhere, after waste water discharge into the river (Chesterikoff, A., Garban, B., Billen, G. and Poulin, M. (1992) Inorganic nitrogen dynamics in the River Seine downstream from Paris (France). Biogeochem. 17, 147-164). Main microbial processes are assumed to be aerobic respiration, nitrification and denitrification. Reactions with iron and manganese, real but not quantitatively important, were neglected. Sulphate reduction and methane formation, certainly not active, were not considered. Denitrification, which is suggested by low nitrate and ammonium concentrations and anoxia in the outflow, is known to be rapid enough to be achieved in a short time (Dupain, S. (1992) Denitrification biologique heterotrophe appliquee au traitement des eaux d'alimentation: Conditions de fonclionnement et mise au point d'un procede. These, Universite Claude Bernard, Lyon). Reaction are somewhat arbitrary but conform to general acceptance (Morel, M. M. and Hering, J. G. (1993) Principles and Applications of Aquatic Chemistry. Wiley, New York). Anaerobic ammonium oxidation (Mulder A., van de Graaf, A. A., Robertson, L: A. and Kuenen, J. G. (1995) Anaerobic ammonium oxidation discovered in a denitrifying fluidized bed reactor. FEMS Microbiol. Ecol. 16, 177-184). although possible, was not considered. In fact, C/N ratio of the reactive organic matter has only mild repercussions on the results; i.e. in the same range as the analytical errors for alkalinity and total carbonates. The objective was simply to roughly confront characteristics of outflowing waters and the calculation. Respective roles of aerobes and denitrifiers, for instance, are not certain. Several periods during low water or floods were selected with various ranges for calcium dissolution or nitrate and oxygen concentrations. The result is that in most cases simulation and data are in reasonable accordance (Fig. 5). Amounts of organic matter in River Loire are generally sufficient to sustain the process (Table 3. Particulate organic matter is probably the most reactive. The balance of oxidation of organic matter indicates that about 65 mu g C-org/l.h are oxidized during the transport without much variation with the river regime or organic discharge. It is concluded that limestone dissolution is directly dependent on organic matter oxidation, but variation occurs (7-29 mg CuCO3/l) with the level of bases that can be neutralized in the River Loire water. (C) 1998 Elsevier Science Ltd. All rights reserved

CO2 source-sink in karst processes in karst areas of China, 1999, Jiang Z. C. , Yuan D. X. ,
The CO2 source-sink of atmospheric greenhouse has a close relationship with karst processes. The corrosion of carbonate rocks lends to the sink of atmospheric CO2, whereas the deposition of carbonate rocks gives off CO2 into atmosphere, which is one of the sources of atmospheric CO2. According to the exposed areas of carbonate rocks in China, the flux of atmospheric CO2 consumed in karst processes is estimated at about 1.77 x 10(13) g CO2/a, Considering the global karst area the flux Of atmospheric CO2 consumed in corrosion may be an important parr of the missing sink. And the sink has a tendency of continuous increase. The release of CO2 from karst water is usually less than the sink of atmospheric CO2 consumed in karst processes. But in active tectonic zone the release of high CO2 concentration of mantle source in the geothermal karst water should not be neglected

The inhibiting action of intrinsic impurities in natural calcium carbonate minerals to their dissolution kinetics in aqueous H2O-CO2 solutions, 1999, Eisenlohr L, Meteva K, Gabrovsek F, Dreybrodt W,
We have measured the surface controlled dissolution rates of natural calcium carbonate minerals (limestone and marble) in H2O-CO2 solutions by using free drift batch experiments under closed system conditions with respect to CO2, at 10 degrees C with an initial partial pressure of carbon dioxide of 5.10(-2) atm. All experiments revealed reaction rates F, which can be described by the empirical relation: F-n1 = k(n1) . (1 - c/c(eq))(n1) for c < c(s), which switches to a higher order n(2) for calcium concentrations c greater than or equal to c(s) described by F-n2 = k(n2) . (1 - c/c(eq))(n2) . k(n1) and k(n2) are rate constants in mmole/(cm(2) . s), c(eq) is the equilibrium concentration with respect to calcite. The values of the constants n(1), n(2), k(n1), k(n2) and c(s) depend on the V/A ratio employed, where V is the volume of the solution and A is the surface area of the reacting mineral. Different calcium carbonate minerals exhibit different values of the kinetic constants. But generally with increasing V/A, there is a steep variation in the values of all kinetic constants, such that the rates are reduced with increasing V/A ratio. Finally with sufficiently large V/A these values become constant. These results are explained by assuming intrinsic inhibitors in the bulk of the mineral. During dissolution these are released from the calcite matrix and are adsorbed irreversibly at the reacting surface, where they act as inhibitors. The thickness d of the mineral layer removed by dissolution is proportional to the VIA ratio. The amount of inhibitors released per surface area is given by d c(int), where c(int) is their concentration id the bulk of the mineral. At low thicknesses up to approximate to 3 . 10(-4) cm in the investigated materials, the surface concentration of inhibitors increases until saturation is attained for thicknesses above this value. To analyze the surface concentration and the type of the inhibitors we have used Auger spectroscopy, which revealed the presence of aluminosilicate complexes at the surface of limestone, when a thickness of d approximate to 10(-3) cm had been removed by dissolution. In unreacted samples similar signals, weaker by one order of magnitude, were observed. Depth profiles of the reacted sample obtained by Ar-ion sputtering showed the concentration of these complexes to decrease to the concentration observed in the unreacted sample within a depth of about 10 nm. No change of the concentration with depth was observed in unreacted samples. These data suggest that complexes of aluminosilicates act as inhibitors, although other impurities cannot be excluded. Copyright (C) 1999 Elsevier Science Ltd

Soil-released carbon dioxide from microbial biomass carbon in the cultivated soils of karst areas of southwest China, 2000, Piao H. C. , Wu Y. Y. , Hong Y. T. , Yuan Z. Y. ,

A model of early evolution of karst conduits affected by subterranean CO2 sources, 2000, Gabrovsek F, Menne B, Dreybrodt W,
In investigating early karstification of one-dimensional conduits by computer models, so far one has assumed that the CO2 content of the calcite aggressive water stems entirely from the surface. Subterranean sources of CO2, however, can rejuvenate the solutional power of water already close to equilibrium with respect to calcite, and boast dissolution rates. In a first scenario we have investigated the influence of a punctual source of CO2 as the most simple case of release of CO2 into a karstifiable fracture at some position KL from its entrance of the widening joint with length L, (K < 1). The results show that only a small increase of the p(CO2) in the solution to about 0.01 atm is sufficient to reduce the breakthrough times to about 0.3 with respect to the case, where no CO2 is delivered. Other sources of CO2 are due to the metabolic activity of microorganisms. The existence of such diverse subterraneous microbial life in karst systems demonstrated. Whether situated on the fissure surfaces or free floating in the karst water, one basic product of their metabolism is CO2. This contributes over the whole flow path to the p(CO2) of the karst water. Therefore in a second scenario we assumed a constant rate of CO2-input along parts of the fracture, as could be delivered by the activity of aerobic bacteria dwelling at its walls. Such a scenario also applies to an extended diffuse CO2 migration from volcanic activity deep underground. In this case drastic reductions of the breakthrough time by about one order of magnitude are observed. These reductions are enhanced when the fracture aperature width of the initial fracture decreases. The physicochemical mechanisms of enhancement of karstification are discussed in detail by considering the evolution of the fracture aperature width and of the dissolution rates in space and time

Simulated effect of vadose infiltration on water levels in the Northern Guam Lens Aquifer, 2000, Contractor Dn, Jenson Jw,
Regional-scale hydrology of the fresh water lens in the Northern Guam Lens Aquifer has been simulated in the past using a finite element, sharp interface computer model, SWIG2D. Systematic differences exist between observed and computed water levels. Computed seasonal peak water levels are higher, and the computed seasonal lows are lower than the respective observed levels. It is hypothesized that vadose storage must store a substantial amount of water during the wet season and release it gradually into the lens during the dry season. Flow through the vadose zone was simulated with a one-dimensional finite element, unsaturated flow program UNSATID, in which the van Genuchten model is used to characterize unsaturated diffuse flow through the matrix of the vadose zone. An additional parameter (SINK) was added to the van Genuchten set to account for rapid infiltration down open pathways (fractures) associated with the closed depressions of the karst terrain. A global-optimization technique (Shuffled Complex Evolution or SCE-UA Method) was used to obtain the parameters that minimized the difference between simulated and observed water levels. Simulations incorporating the van Genuchten model were accomplished by combining the two programs, UNSATID and SWIG2D, into a single program. The sum-of-squared-errors (SSE) between computed and observed water levels in four observation wells was minimized using SCE-UA, reducing the arithmetically averaged SSE of the four wells by 30% compared with the SSE obtained when the vadose zone was not modeled. These results suggest that vadose storage is significant. On the other hand, the fact that the best fit obtained with an optimum parameter set was able to reduce the SSE by no more than 30% suggests that additional phenomena have yet to be accounted for to mon fully explain differences between simulated and observed well water levels. (C) 2000 Elsevier Science B.V. All rights reserved

Quantification of thermo-erosion in pro-glacial areas - examples from Svalbard, 2000, Etzelmuller B,
Surface changes in recently deglaciated terrain are calculated by comparing air-photo derived digital elevation models (DEMs) from four pro-glacial areas on Svalbard. The paper quantifies the amount of material mobilised due to thermo-karst processes and discusses the influence of the process on the sediment budget of terrestrial arctic glacier basins underlain by permafrost. The study shows that thermo-erosion in deglaciated terrain is an important process which falls within the concept of paraglacial activity. The average annual material mobilisation due to thermo-erosion can be in the same order of magnitude as field-measured total annual suspended sediment transfer out of the catchments. The study implies further that ice-cored moraines are important sediment magazines, which release more material during warmer periods than during colder periods

Water-upwelling pipes and soft-sediment-deformation structures in lower Pleistocene calcarenites (Salento, southern Italy), 2001, Massari F. , Ghibaudo G. , D'alessandro A. , Davaud E. ,
A thin sedimentary blanket, consisting mostly of subtidal, unconformity-bounded calcarenite units, was deposited in the small Novoli graben (Apulian foreland, southern Italy) in Pliocene-Pleistocene time. In a limited part of the study area the lower Pleistocene 'Calcarenite di Gravina,' forming the thicker part of this blanket, is crossed by continuous to discontinuous cylindrical pipes as much as 12 m high, most commonly consisting of stacked concave- upward laminae, locally grading upward into soft-sediment-deformation features and large dishes. The evidence favors an origin linked to upwelling of overpressured groundwater from a large karstic reservoir hosted in the Mesozoic carbonate rocks; the reservoir periodically developed a relatively high hydrostatic head due to Tertiary to Pleistocene cover acting as an aquitard or aquiclude. As a result, submarine springs were generated, the activity of which was primarily controlled by relative sea-level fluctuations. It is suggested that the pipes were located in those points where the hydrostatic pressure was sufficient to fluidize the overlying sediment and could be released without notably affecting the surrounding sediments. Some pipes cross calcarenitic infills of karstic sinkholes developed in the underlying units, whereas others follow the course of vertical to high-angle extensional synsedimentary tectonic fractures generated when the calcarenites were still in an unconsolidated to semiconsolidated state. The former relationships suggest that vertical routes of water upwelling during highstand of base level commonly coincided with axes of vadose solution during base-level lowstand; the latter suggest that opening of fractures enhanced the connection of the deep aquifer with the surface, hence intensifying water upwelling. We think that fluidization along the fractures was not hindered by the partially coherent state, and that pipes with a cylindrical geometry could form in spite of the planarity of the fractures. The formation of the pipes and their internal structure of stacked concave-upward laminae is thought to be consistent with a process of fluidization due to through-flowing waters. We believe that essential in this process is the role of upward-migrating transient water-filled cavities, akin to the voidage waves (Hassett's [1961a, 1961b] parvoids) experimentally reproduced by several authors in liquid fluidized beds, and regarded as true instability phenomena of a fluidized suspension occurring above minimum fluidization velocity. It is suggested that the process is akin to the production of the dish structure. It consists of the filling of transient, upward-migrating, water-filled cavities through steady fallout of particles from the cavity roof, their redeposition in a more consolidated state, and subsidence of the roof due to water seepage upward from the cavity. The process was accompanied by segregation of grains according to their size and density, as well by elutriation of finest particles, and led to a new pattern of sediment texture, packing, and fabric with respect to the surrounding calcarenites

Derivation of effective hydraulic parameters of a karst aquifer from discharge hydrograph analysis, 2001, Baedke Sj, Krothe Nc,
In well-developed karst terrains, three or more distinct portions of the karst continuum can be identified from hydrographs of springs issuing from the karat aquifer. Hydrographs from mio karat springs within the same drainage basin at the Crane Naval Surface Warfare Center, Indiana, have been analyzed, and ratios of transmissivity and specific yield (T/S-y) have been established for the conduit and diffuse flow systems. These ratios have been compared with values of T derived from aquifer tests, so that independent values of S-y can be calculated for the diffuse system. Similarly, if the value of S-y is assumed to be 1.0 for a pure conduit, then independent values of T can be calculated for this end-member of the karst continuum. The values of T and S-y derived from this study are similar to values obtained from a dye trace of the conduit-dominated flow system and of values derived from aquifer tests of the diffuse flow system. Values of T for the conduit system of these springs may need to be established at a local scale, while the values for the diffuse flow system may be applicable at a regional scale. A hydrograph separation using isotopic data suggests that the intermediate-flow system represents a mix of water from the conduit and diffuse flow systems. If this portion of the hydrograph is a truly mixing phenomena, ratios of TIS cannot be determined from the hydrograph analysis presented herein. However. if instead, the intermediate-flow system represents water released from a third reservoir (such as small fractures), ratios of T/S, can be established for the intermediate-flow system

Dynamics of Cave development by Allogenic water, 2001, Palmer, Arthur N.

Streams that drain from non karstic surfaces tend to have great discharge fluctuations and low concentrations of dissolved solids. Where these streams encounter karstic rocks they can form caves with hydraulic and chemical dynamics quite different from those fed by autogenic recharge (e.g. through dolines). Caves in carbonate rocks that are fed by allogenic streams have a relatively short inception period, after which the mean annual rate of dissolutional wall retreat is typically about 0.01 cm/yr. Most of the annual growth takes place during a few major floods that occupy only a small fraction of the year. Local growth rates can be enhanced by abrasion from sediment. During floods, highly aggressive water is delivered rapidly to points deep within the karst aquifer. As flood discharge increases, cave streams become ponded by constrictions caused by detrital sediment, insoluble beds, or collapse material. Because the discharge during a flood rises by several orders of magnitude, the head loss across constrictions can increase enormously, causing water to fill parts of the cave under considerable pressure. This highly aggressive water is injected into all available openings in the surrounding bedrock, enlarging them at a rapid and nearly uniform rate. Depending on the structural nature of the bedrock, a dense array of blind fissures, pockets, anastomoses, or spongework is formed. Many such caves develop traversable mazes that serve either as bypass routes around constrictions, or as "karst annexes", which store and later release floodwaters. Many features that are sometimes attributed to slow phreatic flow or mixing corrosion are actually generated by ponded floodwaters. In caves that experience severe flooding, adjacent fissures or bypass routes with initial widths at least 0.01 cm can grow to traversable size within 10,000 years.

Ochtina Aragonite Cave (Western Carpathians, Slovakia): Morphology, mineralogy of the fill and genesis, 2002, Bosak P, Bella P, Cilek V, Ford Dc, Hercman H, Kadlec J, Osborne A, Pruner P,
Ochtina Aragonite Cave is a 300 m long cryptokarstic cavity with simple linear sections linked to a geometrically irregular spongework labyrinth. The metalimestones, partly metasomatically altered to ankerite and siderite, occur as isolated lenses in insoluble rocks. Oxygen-enriched meteoric water seeping along the faults caused siderite/ankerite weathering and transformation to ochres that were later removed by mechanical erosion. Corrosion was enhanced by sulphide weathering of gangue minerals and by carbon dioxide released from decomposition of siderite/ankerite. The initial phreatic speleogens, older than 780 ka, were created by dissolution in density-derived convectional cellular circulation conditions of very slow flow. Thermohaline convection cells operating in the flooded cave might also have influenced its morphology. Later vadose corrosional events have altered the original form to a large extent. Water levels have fluctuated many times during its history as the cave filled during wet periods and then slowly drained. Mn-rich loams with Ni-bearing asbolane and bimessite were formed by microbial precipitation in the ponds remaining after the floods. Allophane was produced in the acidic environment of sulphide weathering. La-Nd-phosphate and REE enriched Mn-oxide precipitated on geochemical barriers in the asbolane layers. Ochres containing about 50 wt.% of water influence the cave microclimate and the precipitation of secondary aragonite. An oldest aragonite generation is preserved as corroded relics in ceiling niches truncated by corrosional bevels. Thermal ionisation mass spectrometry and alpha counting U series dating has yielded ages of about 500-450 and 138-121 ka, indicating that there have been several episodes of deposition, occurring during Quaternary warm periods (Elsterian 1/2, Eemian). Spiral and acicular forms representing a second generation began to be deposited in Late Glacial (14 ka - Allerod) times. The youngest aragonite, frostwork, continues to be deposited today. Both of the, younger generations have similar isotopic compositions, indicating that they originated in conditions very similar, or identical, to those found at present in the cave

Effects of precipitation events on colloids in a karst aquifer, 2002, Shevenell L. , Mccarthy J. F. ,
The effects of precipitation events on colloid mobilization were evaluated during several storms from six wells in a karstic aquifer at the Oak Ridge Y-12 Plant in eastern Tennessee (USA). Turbidity increases and rapidly recedes following rain events. Although the magnitude of the turbidity increases are relatively small (less than or equal to4.78 NTU), the increased turbidity suggests transient increases in colloid abundance during storm versus non-storm periods. During the larger storms (> 19 mm), the increased turbidity is associated with increases in pH, total organic carbon (TOC) and temperature, and with decreases in dissolved oxygen (DO). These larger storms result in flushing of a greater proportion of higher pH, TOC (and lower DO) soil or matrix waters into the fractures and conduits than occurs during smaller storms. Smaller storms also result in increases in turbidity, but show increases in DO and decreases in pH reflecting less influence on the water chemistry from the longer residence time epikarst or and matrix waters, and greater impact from the more dilute, newly recharged waters. Due to the complexity of karst flow and temporal variations in flow and chemistry, controls on turbidity are not consistent through time and space at the wells. During smaller storms. recharge by lower ionic strength waters may promote colloid release and thus contribute to observed increases in turbidity. During larger storms, elevated turbidity may be more related to pH increases resulting from greater influx of matrix and soil waters into fractures and conduits. Chemical factors alone cannot account for the changes in turbidity observed during the various storms. Because of the complicated nature of flow and particle transport in karst aquifers, the presence of colloids during precipitation events is dictated by a complex interplay of chemical reactions and the effects of physical perturbations due to increased flow through the conduits and fractures. Simple trends in water quality parameters could not be identified, and broad generalizations cannot easily be made in karst settings, and some of the expected correlations between chemical parameters during the storms were not observed in this work. (C) 2002 Elsevier Science B.V. All rights reserved

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