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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 streamline is a curve that is everywhere tangent to the specific discharge vector and indicates the direction of flow at every point in a flow domain.?

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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 preferential flow (Keyword) returned 31 results for the whole karstbase:
Showing 1 to 15 of 31
Modeling of regional groundwater flow in fractured rock aquifers, PhD Thesis, 1990, Kraemer, S. R.

The regional movement of shallow groundwater in the fractured rock aquifer is examined through a conceptual-deterministic modeling approach. The computer program FRACNET represents the fracture zones as straight laminar flow conductors in connection to regional constant head boundaries within an impermeable rock matrix. Regional scale fracture zones are projected onto the horizontal plane, invoking the Dupuit-Forchheimer assumption for flow. The steady state flow solution for the two dimensional case is achieved by requiring nodal flow balances using a Gauss-Seidel iteration. Computer experiments based on statistically generated fracture networks demonstrate the emergence of preferred flow paths due to connectivity of fractures to sources or sinks of water, even in networks of uniformly distributed fractures of constant length and aperture. The implication is that discrete flow, often associated with the local scale, may maintain itself even at a regional scale. The distribution of uniform areal recharge is computed using the Analytic Element Method, and then coupled to the network flow solver to complete the regional water balance. The areal recharge weakens the development of preferential flow pathways. The possible replacement of a discrete fracture network by an equivalent porous medium is also investigated. A Mohr's circle analysis is presented to characterize the tensor relationship between the discharge vector and the piezometric gradient vector, even at scales below the representative elementary volume (REV). A consistent permeability tensor is sought in order to establish the REV scale and justify replacement of the discrete fracture network by an equivalent porous medium. Finally, hydrological factors influencing the chemical dissolution and initiation of conduits in carbonate (karst) terrain are examined. Based on hydrological considerations, and given the appropriate geochemical and hydrogeological conditions, the preferred flow paths are expected to develop with time into caves.


USING GROUND-PENETRATING RADAR TO INVESTIGATE A SUBSURFACE KARST LANDSCAPE IN NORTH-CENTRAL FLORIDA, 1994, Collins Me, Cum M, Hanninen P,
Doline formation in karst areas has been a major concern in Florida. Recently, there has been increased interest in investigating the subsurface conditions that influences preferential flow in these karst landscapes. This information is necessary to improve transport and fate models of contaminants. In addition, there is interest in knowing if the formation and expansion of dolines can be predicted by studying subsurface conditions and flow patterns. The soils on the Newberry Limestone Plain are typically sandy above a thin or absent phosphatic, clayey Hawthorne Formation. Underlying this formation is the Crystal River Limestone. A field survey with ground-penetrating radar (GPR) was conducted on the Newberry Limestone Plain at a site with recently formed dolines. The objectives were (i) to investigate the subsurface materials, (ii) to ascertain subsurface landscape variability, (iii) to relate the subsurface landscapes to subsurface flow patterns, and (iv) to predict doline growth and formation in the study area. The results of this study indicated that the subsurface features; presence of clay over limestone, location of solution pipes and paleo-dolines are variable. In general, the subsurface landscape does not follow the surface topography. Subsurface solute movement can be estimated in these landscapes assuming the clay layer that drapes the limestone acts as an aquatarde. Thus, subsurface modeling of flow at the study site is improved. Locations of paleo-dolines and solution pipes were obvious in the radar data. Predictions, though, of future doline formation and growth at the study site were difficult with GPR. Fracture patterns, e.g. dips in the limestone, can be evaluated and weak zones where paleo-dolines have formed can be identified. This study would not have been possible without the use of the GPR. The radar was able to obtain continuous information on 16% of the site to a depth of 3 m. A highly detailed soil survey using conventional methods would have provided only 0.8% coverage of the site

ESTIMATION OF PREFERENTIAL MOVEMENT OF BROMIDE TRACER UNDER FIELD CONDITIONS, 1994, Jabro J. D. , Lotse E. G. , Fritton D. D. , Baker D. E. ,
Leaching of agricultural chemicals from the root and vadose zones into groundwater is an important environmental concern. To procure a better understanding of the movement and transport of agricultural chemicals through the soil profile, a field research study was conducted to estimate bromide leaching losses under saturated conditions where preferential flow is occurring. The field data were then used to evaluate the LEACHM model. Eighteen double-ring infiltrometers were used to apply a pulse (100 mm depth) of bromide tracer on two previously saturated soils located in a karst region of southeastern Pennsylvania. Internal drainage over the next seven days resulted in nearly 51 % of the applied Br- being leached to a depth below 0.80 m. The LEACHM model was used to simulate the amount of bromide leached in each infiltrometer. The model predicted, accurately, an average of 46% of the applied Br- leached below the 0.80 m depth. Mcan values of bromide concentration in the soil profile were predicted within two standard deviations of the measured mean for all depths except for the 0.20-0.40 m depth increment where the model overpredicted the bromide concentration. The model predictions of Br- leached were tested against field measurements using several statistical tests. The LEACHM model performed adequately under preferential flow conditions, perhaps because the infiltration rate at each site was used as a model input. This, actually, is some measure of the macropore flow process and suggests that simple models such as LEACHM can be used in the field, as long as a distribution of infiltration rates is used as an input

EARLY DEVELOPMENT OF KARST SYSTEMS .1. PREFERENTIAL FLOW PATH ENLARGEMENT UNDER LAMINAR-FLOW, 1994, Groves C. G. , Howard A. D. ,
Modeling of flow and solutional processes within networks of interconnected conduits in limestone aquifers indicates that enlargement occurs very selectively during the early stages of karst aquifer development under laminar flow. If initial flow paths are uniform in size, almost all enlargement occurs along a single set of connected conduits that lie along a direct path between recharge and discharge locations and are aligned along the hydraulic gradient. With a sufficiently large variation in initial aperture widths, enlargement occurs along the flow path offering the least resistance to flow, but since flow rates in laminar flow are proportional to the fourth power of diameter but only linearly proportional to hydraulic gradient, the preferentially enlarged set of fractures may follow an indirect path. Results disfavor earlier suggestions that nonselective cave patterns result from artesian flows (at least under laminar flow conditions) and that all passages should be competitive until the onset of turbulent flow

Using ground-penetrating radar to investigate a subsurface karst landscape in north-central Florida, 1994, Collins M. E. , Cure M. , Hanninen P.

Doline formation in karst areas has been a major concern in Florida. Recently, there has been increased interest in investigating the subsurface conditions that influences preferential flow in these karst landscapes. This information is necessary to improve transport and fate models of contaminants. In addition, there is interest in knowing if the formation and expansion of dolines can be predicted by studying subsurface conditions and flow patterns. The soils on the Newberry Limestone Plain are typically sandy above a thin or absent phosphatic, clayey Hawthorne Formation. Underlying this formation is the Crystal River Limestone. A field survey with ground-penetrating radar (GPR) was conducted on the Newberry Limestone Plain at a site with recently formed dolines. The objectives were (i) to investigate the subsurface materials, (ii) to ascertain subsurface landscape variability, (iii) to relate the subsurface landscapes to subsurface flow patterns, and (iv) to predict doline growth and formation in the study area. The results of this study indicated that the subsurface features; presence of clay over limestone, location of solution pipes and paleo-dolines are variable. In general, the subsurface landscape does not follow the surface topography. Subsurface solute movement can be estimated in these landscapes assuming the clay layer that drapes the limestone acts as an aquatarde. Thus, subsurface modeling of flow at the study site is improved. Locations of paleo-dolines and solution pipes were obvious in the radar data. Predictions, though, of future doline formation and growth at the study site were difficult with GPR. Fracture patterns, e.g. dips in the limestone, can be evaluated and weak zones where paleo-dolines have formed can be identified. This study would not have been possible without the use of the GPR. The radar was able to obtain continuous information on 16% of the site to a depth of 3 m. A highly detailed soil survey using conventional methods would have provided only 0.8% coverage of the site


INFILTRATION MECHANISMS RELATED TO AGRICULTURAL WASTE TRANSPORT THROUGH THE SOIL MANTLE TO KARST AQUIFERS OF SOUTHERN INDIANA, USA, 1995, Iqbal M. Z. , Krothe N. C. ,
A hydrogeological study was conducted, during the 1991-1992 water year, in the clay-soil mantled portion of a limestone terrain in southern Indiana. The purpose of the study was to investigate the modes of soil-water infiltration contributing to rapid transport of nitrate to the saturated zone. The I-year-cycle profiles of nitrate concentration vs. time show a consistent increase of nitrate at various depths in the unsaturated zone during the period of investigation. The increase of nitrate in soil water is attributed to the rapid flushing of the inorganic fertilizers from the fields after the area received sufficient rainfall in late fall. The investigation also showed a major movement of nitrate in quick pulses through the unsaturated zone, rather than a slow uniform recharge, immediately after a major storm event. The asymmetric profiles of nitrate concentration vs. depth point to the existence of preferential flow through macropores in the clay-soil mantle above the bedrock. Soil-water transport between storm events is by matrix type flow. Nitrogen isotopes were analyzed for representative groundwater samples collected before and immediately after fertilization of fields in the summer, 1991. The delta(15)N values of the samples did not show any major shift in nitrate sources between the sampling periods. The summer of 1991 was extremely dry prohibiting vertical transport of nitrate from the fields to the groundwater system. Any change in nitrate concentration in groundwater during this time is attributed to the mixing through lateral flow within the aquifer

Endokarst processes in the Alburni massif (Campania, southern Italy): evolution of ponors and hydrogeological implications, 1997, Santangelo N. , Santo A. ,
The Alburni carbonatic massif located within the southern Apennines chain, represents one of the most important Italian karstic areas. Within an area of about 280 square kilometres more than 200 caves are known and many important basal springs are present. This paper concerns ponor systems which are among the best developed endokarst morphologies in the area. In particular it deals with their morphological evolution and with their role in the underground hydrological circulation of the massif. The ponors can be defined as ''contact ponors'' since their entrances are always located at the contact between permeable carbonatic rocks and impermeable flysch formations. Two categories of ponors are present, active and inactive ones, latter due to erosion and lowering of the boundary between impermeable and permeable deposits. The ponors are located on the Alburni highland at a mean altitude of 1100 metres and they transfer water collected by catchment basin laying on flysch deposits down to the main basal springs, the altitudes of which range from 250 to 70 metres a.s.l. The structural setting of the massif strongly influences both the main directions along which the caves develop and the underground hydric circulation flows. Surface and underground morphostructural data have been compared, showing a general agreement, with frequency peaks at the N50 degrees and N140 degrees directions, though the underground data also outline the existence of a more ancient N90 degrees trend. As shown by speleological survey and tracing tests, the underground drainage is strongly influenced by the presence of karstic channels, and its preferential flow direction points towards the southern sector of the massif, according to the general dipping of the strata

Influence of aperture variability on dissolutional growth of fissures in karst formations, 1998, Hanna R. B. , Rajaram H. ,
The influence of aperture variability on dissolutional growth of fissures is investigated on the basis of two-dimensional numerical simulations. The logarithm of the fissure aperture before dissolution begins is modeled as a Gaussian stationary isotropic random field. The initial phase of dissolutional growth is studied up to the time when turbulent flow first occurs at a point within the fissure (the breakthrough time). The breakthrough time in variable aperture fissures is smaller than that in uniform fissures and decreases as the coefficient of variation of the aperture field (sigma/mu) increases. In comparing uniform and variable aperture fissures in limestone, the breakthrough time with sigma/mu = 0.1 is about a factor of 2 smaller than that in a uniform fissure. The breakthrough time is reduced by about an order of magnitude with sigma/mu = 2.0. The mechanism leading to reduced breakthrough times is the focusing of flow into preferential flow channels which are enlarged at a faster rate than the surrounding regions of slower flow. Dissolution channels are narrower and more tortuous as sigma/mu. increases. Investigations of the influence of reaction rate reveal that the influence of aperture variability is more pronounced in rapidly dissolving rock. In uniform fissures in rapidly dissolving minerals, breakthrough times are very long since water becomes saturated with respect to the mineral within a short distance of the entrance to the flow path. However, in variable aperture fissures, breakthrough occurs rapidly because of selective growth along preferential flow channels, which progressively capture larger fractions of the total flow. These results partly explain why conduits develop rapidly in gypsum, although previous one-dimensional studies suggest that conduit growth will not occur

Spatialized morphological analysis: A method of detecting faults, a necessity for hydrodynamic and karstologic studies of cracked aquifers. Examples of the chalky aquifers of Northern France, 1999, Bonnet T, Colbeaux Jp,
Spatialized Morphological Analysis is a new method of detecting faults which uses the morphometric relief data (slope, aspect, elevation) taken from a precise Digital Elevation Model by a computer program. This program, taking the principles of the evolution of relief into account (rock type, climate, chronology), allows the statistical identification of morphometric standards for each type of morphology and the extraction of anomalies to these standards. Some of these anomalies, after a processing of spatial classification, are considered as tectonic tracks. The actual existence of faults, corresponding with anomalies, is verified by classical methods of structural geology. By a better localisation and geometrical definition of faults, this method can allow the optimization of hydrodynamical studies of cracked aquifers, and in case of calcareous ones, a spatial approach to karstification. This method is applied to the north of France chalky aquifer, where, associated with detailed hydrogeological records, it allowed the identification of rapid transfers of groundwater at the level of faults. Even so, exokarstic phenomena are uncommon in this area. Some chemical and textural particularities of Quaternary chalk cover may be the cause of rainwater inhibition, and it is possible that the karstic responses observed are due to considerable mechanical dissolution in the saturated area where tectonic activity (neotectonic faults have been observed) creates environments of preferential flow. (C) Elsevier, Paris

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

Speleogenesis in the Picos de Europa massif, Northern Spain, 2000, Fernandezgibert E. , Calaforra J. M. , Rossi C.
The Picos de Europa mountain range in Northern Spain represents one of the most important alpine karsts in the world, containing a great concentration of deep limestone caves. It comprises Carboniferous limestones with thicknesses up to 2000 m and severely deformed by tectonic action. The structure and geological evolution, fracturing and Quaternary glaciation are among the main factors influenced the development of the caves. This paper proposes a speleogenetic model of the evolution, with an initial stage during which a Permo-Triassic cover provided semiconfinement for the entire carbonate series. Under these circumstances, the earliest known phreatic conduits were formed. Occasional relict sediments in them are related to the erosion of the cover. During the second stage, with the uplift of the massif, the cover was eroded and vadose conditions established; they were linked to glacial processes that intensified karstification, creating an unsaturated zone almost 2000 m thick. The karstification and vadose entrenchment in this zone are especially marked along preferential flow paths coinciding with pre-existing dolomitized and sulfide-mineralized fractures in the massif. These fractures may also have played a precursor role in the karstic evolution of the massif, as the source for more aggressive waters with a higher content of weak acids due to the oxidation of sulfides.

Field-scale variation of preferential flow as indicated from dye coverage, 2002, Ohrstrom P. Persson M. Albergel J. Zante P. , Nasri S. Berndtsson R. , Olsson J.
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Soil and karst aquifer hydrological controls on the geochemical evolution of speleothem-forming drip waters, Crag Cave, southwest Ireland, 2003, Tooth Anna F. , Fairchild Ian J. ,
In recent years there has been increased interest in cave speleothems as archives of palaeoclimate. Monitoring of rainfall and soil and karst water chemistries was performed at Crag Cave, Castleisland, Co. Kerry, southwest Ireland, in August 1997 and January 1998 in order to understand temporal and spatial variations in karst water hydrology and chemistry and their implications for interpreting the potential palaeohydrological signal preserved by speleothems at this site. Temporal variations in karst water drip rates and geochemistry allow drips to be classified by hydrological response to rainfall and the associated processes of dilution, piston flow, source change and prior calcite precipitation during aquifer throughflow. Evolution from soil matrix and preferential flow solutions has also been determined to exert an important control on karst water chemistries. As a result of these findings we present hydrogeochemical models and plumbing diagrams that delineate the controls on karst water evolution at a number of sampling locations within the cave at this site. We propose that a palaeohydrological signal may be recorded by Crag Cave speleothems that may be interpreted via the study of Mg/Ca ratios in speleothems linked to monitoring of modern drip water chemistry

Using state-wide GIS data to identify the coincidence between sinkholes and geologic structure., 2005, Florea L.
The Kentucky GIS coverage of sinkholes, completed in 2003, consists of 101,176 polygons representing the upper-most closed contour of every karst sinkhole identified using USGS 1:24,000 scale topographic maps. This resource is a useful tool for delineating karst landscapes in Kentucky because karstified limestones underlie 55% of the aerial surface of the state. For hydrologic studies, alignments of sinkholes commonly indicate preferential flowpaths for groundwater; and this information aids in large-scale planning and zoning. In this paper, I demonstrate the effectiveness of using this sinkhole coverage as a tool for delimiting structural features of Kentucky.

Estimation of denitrification potential in a karst aquifer using the N-15 and O-18 isotopes of NO3-, 2005, Einsiedl F, Maloszewski P, Stichler W,
A confined aquifer in the Malm Karst of the Franconian Alb, South Germany was investigated in order to understand the role of the vadose zone in denitrifiaction processes. The concentrations of chemical tracers Sr2 and Cl- and concentrations of stable isotope O-18 were measured in spring water and precipitation during storm events. Based on these measurements a conceptual model for runoff was constructed. The results indicate that pre-event water, already stored in the system at the beginning of the event, flows downslope on vertical and lateral preferential flow paths. Chemical tracers used in a mixing model for hydrograph separation have shown that the pre-event water contribution is up to 30%. Applying this information to a conceptual runoff generation model, the values of delta(15)N and delta(18)O in nitrate could be calculated. Field observations showed the occurence of significant microbial denitrification processes above the soil/ bedrock interface before nitrate percolates through to the deeper horizon of the vadose zone. The source of nitrate could be determined and denitrification processes were calculated. Assuming that the nitrate reduction follows a Rayleigh process one could approximate a nitrate input concentration of about 170 mg/l and a residual nitrate concentration of only about 15%. The results of the chemical and isotopic tracers postulate fertilizers as nitrate source with some influence of atmospheric nitrate. The combined application of hydrograph separation and determination of isotope values in delta(15)N and delta(18)O of nitrate lead to an improved understanding of microbial processes (nitrification, denitrification) in dynamic systems

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