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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 water works is a plant where water is treated and prepared for municipal consumption [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 flux (Keyword) returned 160 results for the whole karstbase:
Showing 16 to 30 of 160
THE EVOLUTION OF THE MIDDLE TRIASSIC (MUSCHELKALK) CARBONATE RAMP IN THE SE IBERIAN RANGES, EASTERN SPAIN - SEQUENCE STRATIGRAPHY, DOLOMITIZATION PROCESSES AND DYNAMIC CONTROLS, 1993, Lopezgomez J. , Mas R. , Arche A. ,
The Upper Permian-Triassic strata of the SE Iberian Ranges, eastern Spain, display the classic Germanic-type facies of Buntsandstein, Muschelkalk and Keuper. The Muschelkalk is represented by two carbonate units with a siliciclastic-evaporitic unit in between. Their ages range from Anisian to basal Carnian (Middle Triassic to base of the Upper Triassic). The carbonate units represent ramps that evolved during the early thermal subsidence period which succeeded the first rift phase. Seven facies have been distinguished, representing shoals, tidal flats, organic buildups and lagoons, as well as a karst horizon in the lower carbonatic unit. Most of the carbonates were dolomitised. Three processes of dolomitization are invoked: mixing waters, penecontemporaneous seepage refluxion, and deep burial. The top of the Buntsandstein and the Muschelkalk facies are subdivided into two depositional sequences, including lowstand, transgressive and highstand systems tracts, with superimposed tectonic and eustatic controls

HYDROGEOCHEMISTRY OF GRAND-CAYMAN, BRITISH-WEST-INDIES - IMPLICATIONS FOR CARBONATE DIAGENETIC STUDIES, 1995, Ng K. C. , Jones B. ,
Groundwater in the dolostone aquifers of the Bluff Group (Oligocene-Miocene) on Grand Cayman is divided into fresh, lightly and highly brackish, and saline (Type I and II) zones according to chemical characteristics that were determined during a 3 year (1985-1988) monitoring program. Brackish and Type I saline waters display the greatest variation in chemical properties whereas the Type II saline water has the most stable chemical characteristics. Most groundwaters from these dolostone aquifers are thermodynamically capable of precipitating calcite and/or dolomite. The saturation indices for these minerals, however, vary through time and space even in the context of small water lens. Simple mixing of fresh and sea water cannot explain the chemistry of the water found in the joint and karst controlled dolostone aquifers of Grand Cayman. Deviation from a simple mixing model is due to variations caused by tidal fluctuation, the rate of rain water recharge, influx of Ca-rich groundwater from the surrounding limestone aquifers, influx of CO2-rich surface water from sinkholes and swamps, and water-rock interactions (dissolution and precipitation of calcite and dolomite). Sustained groundwater abstraction from a lens can significantly alter the hydrochemistry of the water lens. This suggests that hydrochemical characterization of small fresh water lenses, like those on Grand Cayman, cannot be based on spot or short-term sampling. Interpretation of such fluids in terms of calcite-dolomite precipitation and/or dissolution must be treated with caution if the data base has not been derived from long-term monitoring

High-resolution temporal record of Holocene ground-water chemistry; tracing links between climate and hydrology, 1996, Banner Jl, Musgrove M, Asmerom Y, Edwards Rl, Hoff Ja,
Strontium isotope analysis of precisely dated calcite growth layers in Holocene speleothems from Barbados, West Indies, reveals high-resolution temporal variations in ground-water composition and may provide a new approach to documenting the links between climate variability and fluctuations in the hydrologic cycle such as recharge rates and flow paths. The speleothems grew in a cave that developed in a fresh-water aquifer in uplifted Pleistocene reef limestones. Three periods of ground-water Sr isotope evolution are observed: 87 Sr/ 86 Sr values decreased from 6 to 4 ka, increased from 4 to 1 ka, and decreased again after 1 ka. The Sr isotope oscillations appear to record periodic variations in the relative Sr fluxes to ground water from exchangeable soil sites vs. carbonate mineral reactions, as reflected in 87 Sr/ 86 Sr values of modern Barbados ground waters. A hydrologic model that explains changes in ground-water flow routes in karst aquifers as a function of amount of rainfall recharge can account for the speleothem Sr isotope record. Independent Holocene climate records that indicate a major period of aridity at around 1.3-1.1 ka in the American tropics correspond with periodic variations in rainfall on Barbados that are predicted by this hydrologic model

An examination of short-term variations in water quality at a karst spring in Kentucky, 1996, Ryan M. , Meiman J. ,
Water quality at many karst springs undergoes very high amplitude but relatively brief degradation following influxes of runoff. Accurately recording transient variations requires more rigorous sampling strategies than traditional methods, A pilot study to determine the usefulness of high-frequency, flow-dependent sampling strategies, combined with coincidental quantitative dye tracer tests, was implemented in the Big Spring Ground-Water Basin in Mammoth Cave National Park, Kentucky. Data recorded following two separate runoff events showed that the concentrations of two nonpoint source pollutants, fecal coliform bacteria and suspended sediment, greatly exceeded prerunoff event values for very short periods of time, A phreatic conduit segment, calculated at 17 million liters in volume, instantaneously propagated head changes, caused by direct runoff entering the aquifer, from the ground-water inputs to Big Spring, A significant delay between the initial increases in discharge and the arrival of direct runoff, as indicated by a steady decrease in specific conductance, represented the time required to displace this volume of phreatic water, The delay showed that sampling a karst spring only during peak discharge would be an unreliable sampling method. Runoff from two different subcatchments was tagged with tracer dye and the timing of the passage of the resultant dye clouds through Big Spring were compared to water quality variations, Distinct lag times between the arrival of direct runoff at Big Spring and the bacteria and suspended sediment waveforms were shown through the concurrent quantitative tracer tests to be related to the areal distribution of land-cover type within the basin

Hydrogeologic controls on the groundwater interactions with an acidic lake in karst terrain, Lake Barco, Florida, 1996, Lee T. M. ,
Transient groundwater interactions and lake stage were simulated for Lake Barco, an acidic seepage lake in the mantled karst of north central Florida. Karst subsidence features affected groundwater flow patterns in the basin and groundwater fluxes to and from the lake. Subsidence features peripheral to the lake intercepted potential groundwater inflow and increased leakage from the shallow perimeter of the lake bed. Simulated groundwater fluxes were checked against net groundwater flow derived from a detailed lake hydrologic budget with short-term lake evaporation computed by the energy budget method. Discrepancies between modeled and budget-derived net groundwater flows indicated that the model underestimated groundwater inflow, possibly contributed to by transient water table mounding near the lake. Recharge from rainfall reduced lake leakage by 10 to 15 times more than it increased groundwater inflow. As a result of the karst setting, the contributing groundwater basin to the lake was 2.4 ha for simulated average rainfall conditions, compared to the topographically derived drainage basin area of 81 ha. Short groundwater inflow path lines and rapid travel times limit the contribution of acid-neutralizing solutes from the basin, making Lake Barco susceptible to increased acidification by acid rain

The Lower Triassic Montney Formation, west-central Alberta, 1997, Davies Gr, Moslow Tf, Sherwin Md,
The Lower Triassic Montney Formation was deposited in a west-facing, arcuate extensional basin, designated the Peace River Basin, on the northwestern margin of the Supercontinent Pangea, centred at about 30 degrees N paleolatitude. At least seasonally arid climatic conditions, dominance of northeast trade winds, minimum fluvial influx, offshore coastal upwelling, and north to south longshore sediment transport affected Montney sedimentation. Paleostructure, particularly highs over underlying Upper Devonian Leduc reefs and lows associated with graben trends in the Peace River area, strongly influenced Montney depositional and downslope mass-wasting processes. A wide range of depositional environments in the Montney is recorded by facies ranging from mid to upper shoreface sandstones, to middle and lower shoreface HCS sandstones and coarse siltstones, to finely laminated lower shoreface sand and offshore siltstones. and to turbidites. Dolomitized coquinal facies occur at seven stratigraphic horizons in the Montney. Some coquinas are capped by karst breccias and coarse-grained aeolian deflation lag sand residues indicating subaerial exposure. The Montney has been divided into three informal members that have been dated by palynology and compared with global Early Triassic sequences. The subdivisions are: the Lower member, of Griesbachian to Dienerian age, correlated with a third-order cycle; the Coquinal Dolomite Middle member, of mixed Dienerian and Smithian ages; and the Upper member, of Smithian to Spathian age, correlative with two, shorter-duration third-order cycles. A forced regressive wedge systems tract model is adopted for deposition of the Coquinal Dolomite Middle member and for turbidites in the Valhalla-La Glace area of west-central Alberta. With this model, coquinas and turbidites accumulated during falling base level to lowstand, with a basal surface of forced regression at the base of the coquina and a sequence boundary at the top of the coquinal member. This is supported by the evidence for subaerial exposure and maximum lowstand at the top of the coquina. Very limited grain size distribution in the Montney, dominantly siltstone to very fine-grained sandstone, but often very well sorted, is interpreted to reflect an aeolian influence on sediment source and transport, High detrital feldspar and detrital dolomite in the Montney are consistent with (but not proof of) aeolian source from an arid interior, as is high detrital mica content in finer size grades. Extensive and often pervasive dolomitization, and early anhydrite cementation within the Montney, are also consistent with an arid climatic imprint. As new exploratory drilling continues to reveal the wide range of facies in the Montney, it adds to both the complexity and potential of this relatively unique formation in western Canada

Geochemistry and water dynamics: Application to short time-scale flood phenomena in a small Mediterranean catchment .1. Alkalis, alkali-earths and Sr isotopes, 1997, Benothman D, Luck Jm, Tournoud Mg,
We report major, trace elements and Sr isotope data for water samples taken regularly during a four-day-long September flood of a Mediterranean river, the Vene (Herault, S. France). The objective is to combine all these data into a dynamic model that describes the origin(s) and movements of waters and their loads. This river drains the runoff from a small, mainly carbonate, partly karstified watershed with Miocene and Jurassic lithologies. The watershed is also impacted by both agricultural and urban activities. Both the dissolved and the particulate loads were analyzed. Concentrations of the dissolved components show major remobilization of almost all elements during the first few hours of the flood (water treatment plants and aerosol scavenging), followed by a sharp concentration decrease. Some major species return to their previous summer values (Ca, HCO3) while others reach low 'background' levels (Na, K, Cl, SO4). Some trace elements (Rb, Sr, Cs) show similar behaviour but (Ba) appears somewhat unaffected. Trace element concentrations and ratios define two main periods (three in the suspended particulate matter). Ratios do not allow distinguishing between the three main sources for the dissolved load in the first period (Miocene, Jurassic, water treatment plants), but clearly show the Jurassic karst influence later on. The Sr-87/Sr-86 Of the suspended particulate matter is more variable and more radiogenic than in the dissolved phase. Variations in concentration ratios and Sr isotope composition in particulates indicate the large and variable contribution of Miocene silicates with some carbonate. However, there is a need for another component with [Rb]/[Sr] higher than bedrocks, internal or external to the watershed, possibly due to differential erosion. Dissolved Ca and Mg fluxes during the flood were calculated at 0.26 ton and 0.029 ton/km(2), respectively. Even though the carbonate nature of the watershed restricts variability in Sr isotope composition in the dissolved load, we distinguish several endmembers: seawater(approximate to marine rain), Miocene marls, Jurassic limestones, water treatment plants (and possibly another attributable to fertilizers). Combined with major and trace element variational Sr isotope fluctuations indicate time-varying proportions of different water endmembers at the outflow and suggest a general dynamic model. Based on PCA (principal component analysis), a 3D representation allows to visualize the geochemical evolution of the Vene waters. In particular, Sr isotopes clearly indicate that the inflow of karstic waters during the flood was not continuous but occurred as a series of marked oscillations between flowing waters with chemical signature of Miocene lithologies and increasing flushes of deeper waters that interacted with Jurassic lithologies. (C) 1997 Elsevier Science B.V

Particle size distributions in waters from a karstic aquifer: from particles to colloids, 1997, Atteia O, Kozel R,
Waters from the surface hydrologic network and the spring of a karstic aquifer in Switzerland were sampled to analyse their colloidal content. The measurements were done weekly with a single particle counter and were verified by other techniques. The particle size distribution (PSD) was modelled in two portions, below and above 5 mu m, using two types of equation: a power law (Pareto distribution) and an exponential law. The model results matched well with the entire PSD data set by varying the parameter values. The parameters obtained from fitting the measured PSD curves were then interpreted in relation to environmental factors. It appears that the two parts of the curves vary independently. The first part of the PSD curve, relating to the smallest particles, is dependent on the pH value of the spring or the temperature of the surface brook. In contrast, the second part of the curve depends mostly on the spring discharge volume. During high flow events, the major effect of the discharge on particle size occurs during the rising limb of the hydrograph, interpreted as clays deposited in the aquifer and resuspended due to high water velocity. The contrasted behaviour of the two parts of the PSD curves suggested that the break point in the curves represents the limit between colloidal and particulate behaviour. Knowing these dependencies, and the characteristics of the particulate matter, allowed the estimation of the role of the colloids in contaminant transport. Large fluxes of suspended matter, specific to karstic aquifers, demonstrate the critical role of colloids in contaminant transport, which is markedly different from what typically occurs in porous media.

Geochemical evolution of a karst stream in Devils Icebox Cave, Missouri, USA, 1997, Wicks Carol M. , Engeln Joseph F. ,
A 3.7 km flowpath along the main stream channel in Devils Icebox Cave, Boone County, Missouri, was sampled on 23 January, 23 March and 18 September 1994. In January 1994, the water was oversaturated with respect to both calcite and dolomite, and only minor compositional changes were observed along the flowpath. In March 1994, the water was oversaturated with respect to calcite but undersaturated with respect to dolomite. Using a mass-balance approach, the composition of the stream water at downstream locations was predicted by dissolution of dolomite (a maximum of 0.16 mmol s-1) and by a minor amount of calcite precipitation (a maximum of 0.03 mmol s-1). In September 1994, there were increases in the Mg, Ca, and total inorganic carbon (TIC) mass fluxes that were due to the dissolution of dolomite (SIdolomiteSI is saturation index) and calcite (SIcalcite2 of the water should decrease downstream; however, we found an increase in the partial pressure of CO2 along the stream. The source of this additional CO2 is thought to be microbial degradation of bat guano. The decomposition of bat guano appeared to change the composition of the stream water during the period the bats are in the cave, and this change was reflected in the composition of the stream water collected in September 1994. Based on the length of the flowpath and on the average velocity of the water along the flowpath, the travel time of water in this karst stream is less than 4 days. The reactions that control the chemistry of the karst water must be those with equally short characteristic times: the dissolution of dolomite and calcite, CO2 exchange, and microbial degradation of organic matter

Modelling groundwater flow in a karst terrane using discrete and double-continuum approaches - importance of spatial and temporal distribution of recharge., 1997, Mohrlok U. , Sauter M.
Groundwater flow had been modelled in the karst catchment area 'Gallusquelle' (Swabian Alb, SW-Germany) using two different types of modelling approaches. The discrete and the double-continuum model differ in their respective representation of the conduit network and the formulation of the exchange flux of groundwater between fissured system and conduits. In the case of the discrete ipproach this exchange is determined by local hydraulic properties adjacent to the conduits. The double-continuum approach represents this exchange using a 'steady state', lumped parameter. As a result of this fundamental difference between the two approaches, the temporal distribution as well as the percentual allocation of groundwater recharge to conduits and fissured system plays a major role in (the respective model calibration

Storm pulses, thresholds, and fluid mechanics in the transport of clastic sediments in limestone aquifers., 1997, White W. B. , White E. L.
Active conduit systems carry a flux of water from recharge regions to discharge downstream at karst springs. They also carry a flux of clastic sediments. Transport of clastic sediments is episodic. Sediment piles are moved mainly during extreme floods. Relationships between sediment panicle sizes and stream flow can be used to determine paleoflow characteristics of caves passages from the clastic sediments and also to calculate the magnitude of flood pulses needed to maintain the sediment flux.

Symposium Abstract: Solute Flux in Cueva del Molino (Agua), Matienzo, Northern Spain, 1998, Quinn A.

Carbonate deposition, karst dissolution, and carbon dioxide flux in the QuaternaryInternational Geological Correlation Program, Project #37, 1998, Mylroie J. E.

Hydrogeology of Kartchner Caverns State Park, Arizona, 1999, Graf, C. G.
Three distinct hydrogeologic systems occur within Kartchner Caverns State Park, Arizona, each in fault contact with the other two. The southeastern corner and eastern edge of the park is part of the large graben that formed the San Pedro Valley during Miocene Basin and Range faulting. A thick alluvial sequence fills this graben and contains a regional aquifer covering 1000 km. One well in the park penetrates this aquifer. The groundwater level measured in this well was 226 m below land surface (1167 m msl), which is 233 m lower than the lowest measured point inside of Kartchner Caverns (1400 m msl). A pediment occupies a small part of the southwestern corner of the park. Structurally, this feature is part of the Whetstone Mountains horst rising above the park to the west. The pediment consists of a bedrock surface of Precambrian Pinal Schist overlain by a few tens of meters of granite wash sediments. Groundwater occurs at depths of 4-18 m below land surface in wells tapping the granite wash sediments. Data from these wells indicate that the zones of saturation within the granite wash sediments are probably of limited lateral extent and yield little water to wells. At the boundary between the pediment and the carbonate ridge containing Kartchner Caverns, the water table in the granite wash aquifer is 20 m higher than the bottom of the nearest known cave passage, located about 200 m to the east.The arid carbonate hills occupying the northwestern part of the park are the erosional remnants of a fault block (the Kartchner Block) that was displaced downward with respect to the Whetstone Mountains horst to the west. Kartchner Caverns is wholly contained in a ridge of highly faulted Mississippian Escabrosa Limestone and cuts conspicuously across Escabrosa beds dipping 10-40 to the southwest and west. Meteoric water enters the Kartchner Block and Kartchner Caverns from infiltration of runoff in washes that border the block and from overhead infiltration of precipitation. A small amount of groundwater also may flow into the Kartchner Block from the schist pediment to the south. Response in the cave to these fluxes is slow. As calculated from past records, the probability of flooding in the cave in any one year is about 57%.

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

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