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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 energy head is hydraulic head plus velocity head [16].?

Checkout all 2699 terms in the KarstBase Glossary of Karst and Cave Terms

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KarstBase a bibliography database in karst and cave science.

Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
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Featured articles from other Geoscience Journals
Karst environment, Culver D.C.
Mushroom Speleothems: Stromatolites That Formed in the Absence of Phototrophs, Bontognali, Tomaso R.R.; D’Angeli Ilenia M.; Tisato, Nicola; Vasconcelos, Crisogono; Bernasconi, Stefano M.; Gonzales, Esteban R. G.; De Waele, Jo
Calculating flux to predict future cave radon concentrations, Rowberry, Matt; Marti, Xavi; Frontera, Carlos; Van De Wiel, Marco; Briestensky, Milos
Microbial mediation of complex subterranean mineral structures, Tirato, Nicola; Torriano, Stefano F.F;, Monteux, Sylvain; Sauro, Francesco; De Waele, Jo; Lavagna, Maria Luisa; D’Angeli, Ilenia Maria; Chailloux, Daniel; Renda, Michel; Eglinton, Timothy I.; Bontognali, Tomaso Renzo Rezio
Evidence of a plate-wide tectonic pressure pulse provided by extensometric monitoring in the Balkan Mountains (Bulgaria), Briestensky, Milos; Rowberry, Matt; Stemberk, Josef; Stefanov, Petar; Vozar, Jozef; Sebela, Stanka; Petro, Lubomir; Bella, Pavel; Gaal, Ludovit; Ormukov, Cholponbek;
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Your search for code (Keyword) returned 47 results for the whole karstbase:
Showing 1 to 15 of 47
Anomalous behaviour of specific electrical conductivity at a karst spring induced by variable catchment boundaries: the case of the Podstenjšek spring, Slovenia, , Ravbar, N. , Engelhardt, I. , Goldscheider, N.

Anomalous behaviour of specific electrical conductivity (SEC) was observed at a karst spring in Slovenia during 26 high-flow events in an 18-month monitoring period. A conceptual model explaining this anomalous SEC variability is presented and reproduced by numerical modelling, and the practical relevance for source protection zoning is discussed. After storm rainfall, discharge increases rapidly, which is typical for karst springs. SEC displays a first maximum during the rising limb of the spring hydrograph, followed by a minimum indicating the arrival of freshly infiltrated water, often confirmed by increased levels of total organic carbon (TOC). The anomalous behaviour starts after this SEC minimum, when SEC rises again and remains elevated during the entire high-flow period, typically 20–40 µS/cm above the baseflow value. This is explained by variable catchment boundaries: When the water level in the aquifer rises, the catchment expands, incorporating zones of groundwater with higher SEC, caused by higher unsaturated zone thickness and subtle lithologic changes. This conceptual model has been checked by numerical investigations. A generalized finite-difference model including high-conductivity cells representing the conduit network (“discrete-continuum approach”) was set up to simulate the observed behaviour of the karst system. The model reproduces the shifting groundwater divide and the nearly simultaneous increase of discharge and SEC during high-flow periods. The observed behaviour is relevant for groundwater source protection zoning, which requires reliable delineation of catchment areas. Anomalous behaviour of SEC can point to variable catchment boundaries that can be checked by tracer tests during different hydrologic conditions.

A New Equation Solver for Modeling Turbulent Flow in Coupled Matrix‐Conduit Flow Models, ,

Karst aquifers represent dual flow systems consisting of a highly conductive conduit system embedded in a less permeable rock matrix. Hybrid models iteratively coupling both flow systems generally consume much time, especially because of the nonlinearity of turbulent conduit flow. To reduce calculation times compared to those of existing approaches, a new iterative equation solver for the conduit system is developed based on an approximated Newton–Raphson expression and a Gauß–Seidel or successive over-relaxation scheme with a single iteration step at the innermost level. It is implemented and tested in the research code CAVE but should be easily adaptable to similar models such as the Conduit Flow Process for MODFLOW-2005. It substantially reduces the computational effort as demonstrated by steady-state benchmark scenarios as well as by transient karst genesis simulations. Water balance errors are found to be acceptable in most of the test cases. However, the performance and accuracy may deteriorate under unfavorable conditions such as sudden, strong changes of the flow field at some stages of the karst genesis simulations.

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Sport and Scout Caving - The Present Dilemma, 1987, Crabb, Evalt

This paper traces the evolution of organised caving as a post World War 2 phenomenon, and the changes in practice and attitude that have occurred. These practices are contrasted against stated behavioural codes. Parallel to this, the development of caving as a scouting activity is discussed, with reference to the general principles and practices of scouting. The author has been working toward evolving policies and practices within scouting which are consistent with the needs of conservation and the underlying philosophies of scouting. Implementation of these attitudes in one area is fully detailed, with some comment on the success and acceptability of the program. This training program is contrasted against the foreshadowed N.S.W. Branch Policy on Rock-Related Activities. The sequential discussion highlights some weaknesses within clubs and A.S.F., particularly in our methods of communication. There are no firm proposals, but possible directions for future discussions are indicated. It is the intention of this paper to give a historical perspective to some of the present perceived conflicts; in reality, the only conflict is between our oft-expressed aim of conservation of caves (i.e. safeguard the karst heritage of Australia), and our visible activity - use of caves for recreational activity. Both the intensity of expression of our concern, and lessening of self-constraint on recreational activity have greatly magnified with time; we are fast approaching a 'crossroads' scenario where our credibility is at great risk.

An instantaneous point injection of an artificial tracer makes it possible to identify the studied system directly. Whether or not convolutions can be carried out depends on the linearity and stationarity of the tracer-test system. Convolutions from the relations between the impulse responses and the hydrodynamic conditions in time-dependent systems are only allowed under special conditions. The framework in which such convolutions are possible is established and a convolution integral proposed which makes it possible to obtain the result of any input in time at one of the outlets of a vectorial system when an artificial tracer test has been carried out between the injection point and this outlet. A few theoretical examples of convolution results with variable flow rates are presented; these results were obtained with a computer code based on the proposed convolution integral

Numerical multisource and multiscale imagery in the study of the topographic surface. Hydrogeological application in a karstic environment: Verneuil-sur-Avre (Perche, France), 1996, Sykioti O. , Deffontaines B. , Chorowicz J. , Obert D. , Demarsily G. , Lauverjat J. , Carvalho J. ,
We propose a new method revealing geological structures and their possible relationships with water percolation. It is based on a combination of (1) numerical analysis of the topography (satellite imagery Landsat TM, HCMM, SAR-ERS1; digital elevation model and derived data: drainage network, slope map, summit level surfaces...); (2) classic geological approach (field work, geological mapping, gravimetry); and (3) hydrogeological approach (piezometric map, tracer experiments). The superimposition of these data into a geocoded data base leads to the identification and the location of morphostructures (synthetic structural map). Field data and tracer experiments confirm the validity of the results. We propose to take into consideration the present day stress regime in order to define main orientations of open fractures. In conclusion, this method provides structural information allowing a better understanding of geometry in karstic aquifers

Dedolomitization as a driving mechanism for karst generation in Permian Blaine formation, southwestern Oklahoma, USA, 1997, Raines M. A. , Dewers T. A. ,
Cyclic deposits of Permian shales, dolomites, and halite and gypsum-bearing strata in the Blaine Formation of Southwestern Oklahoma contain abundant karst features. The present study shows that an important mechanism of karst development in these sequences is dedolomitization, wherein gypsum and dolomite in close spatial proximity dissolve and supersaturate groundwaters with respect to calcite. The net loss of mass accompanying this process (dolomite and gypsum dissolution minus calcite precipitation) can be manifest in secondary porosity development while the coupled nature of this set of reactions results in the retention of undersaturated conditions of groundwater with respect to gypsum. The continued disequilibrium generates karst voids in gypsum-bearing aquifers, a mineral-water system that would otherwise rapidly equilibrate. Geochemical modeling (using the code PHRQPITZ, Plummer et al 1988) of groundwater chemical data from Southwestern Oklahoma from the 1950's up to the present suggests that dedolomitization has occurred throughout this time period in evaporite sequences in Southwestern Oklahoma. Reports from groundwater well logs in the region of vein calcite suggest secondary precipitation, an observation in accord with dedolomite formation In terms of the amounts of void space produced by dissolution, dedolomitization can dominate gypsum dissolution alone, especially in periods of quiescent aquifer recharge when gypsum-water systems would have otherwise equilibrated and karst development ceased. Mass balance modeling plus molar volume considerations show that for every cubic cm of original rock (dolomite plus gypsum), there is 0.54 cm(3) of calcite and 0.47 cm(3) of void space produced Only slightly more pore space results if the dedolomitization reaction proceeds by psuedomorphic replacement of dolomite by calcite than in a reaction mechanism based on conservation of bicarbonate

Least-squares fit of an ellipse to anisotropic polar data: Application to azimuthal resistivity surveys in karst regions, 1997, Hart D. , Rudman A. J. ,
Polar plots of various types of anisotropic data are often approximated by ellipses and used by earth scientists as part of the interpretation process. FITELLIPSE, a code to calculate the orientation and values of the major and minor axes of a best-fit ellipse to anisotropic data, is written using Maple, a standard commercial software. A nonlinear statistical parameter is calculated to evaluate the goodness-of-fit. Application to azimuthal resistivity in karst of Indiana demonstrates the direction and degree of the anisotropy. (C) 1997 Elsevier Science Ltd

The problem of modeling limestone springs: The case of Bagnara (north Apennines, Italy), 1997, Angelini P, Dragoni W,
The Bagnara spring (Central Italy), fed by a fractured, carbonate, and, in some areas, karstic aquifer, was examined. The available information is derived from geological mapping and daily flows over a period of 20 consecutive years. There are no data on the hydrogeological parameters nor on the aquifer hydraulic head, which is known only at the elevation of the spring. The objective of the work was to construct an appropriate mathematical model for the spring despite the scarcity of available information. The MODFLOW code was used to simulate the system following the equivalent porous media approach. The hydraulic conductivity and the specific yield equivalents were estimated by calibrating the model on the master depletion curve and taking into consideration the topographic elevation of the system's surface. The size of the protection area around the spring was investigated on the basis of the isochrons constructed from the results of the model

Bridging the gap between real and mathematically simulated karst aquifers, 1999, Groves C. , Meiman J. , Howard A. D.
Although several numerical codes have been developed to study the patterns of karst aquifer evolution and behavior, in the current generation of models simplifying assumptions must be made because of incomplete quantitative understanding of key processesA one-year, high-temporal-resolution study of carbonate chemistry with Mammoth Cave's Logsdon River, designed to investigate details of these processes, reveals that limestone dissolution rates vary appreciably over storm and seasonal time scales due to variations in the flux of CO2-rich waters that wash through, and flood, conduits during storm eventsThis undersaturated storm water dissolves rock within a flood zone 25-30 m thickThrough the year, waters were undersaturated only 31% of the timeTime scales of actual karst development may thus be impacted by time-varying processes different from the constant-input chemistry assumed in current published numerical codesA dual approach, coupling quantitative modeling and refinement of the models by careful measurement of processes within real karst aquifers, provides a framework for developing a comprehensive understanding of karst system behavior

Investigation of flow in water-saturated rock fractures using nuclear magnetic resonance imaging (NMRI), 1999, Dijk P. , Berkowitz B. , Bendel P.

The application of nuclear magnetic resonance imaging (NMRI) to the direct three-dimensional measurement of flow in rough-walled water-saturated rock fractures is presented for the first time. The study demonstrates the abilities of NMRI to noninvasively measure rock-water interfaces and water flow velocities in these fractures and investigates the effects of wall morphology on flow patterns inside a typical rock fracture. Two- and three-dimensional flow-encoded spin-echo pulse sequences were applied. The stability and reproducibility of the water flow patterns were confirmed by analyzing two-dimensional velocity images. A variety of geometrical and hydraulic features were determined from three-dimensional velocity images, including the rock-water interfaces, the fracture aperture distribution, and the critical aperture path; velocity profiles and volumetric flow rates; flow and stagnant regions; and the critical velocity path. In particular, the effects of a sharp step discontinuity of the fracture walls and the applicability of the cubic law were examined. As a result of the complex three-dimensional geometry, velocity profiles are generally parabolic but often highly asymmetric, with respect to the fracture walls. These asymmetric velocity profiles are clustered together, with significant correlations; they are not just local random phenomena. However, theoretical considerations indicate that the effects of the measured asymmetry on volumetric flow rates and hydraulic conductivities are insignificant, in that the overall flow inside rough fractures still obeys the cubic law. The features discussed in this study emphasize the strong heterogeneity and the highly three-dimensional nature of the flow patterns in natural rock fractures and consequently the need for three-dimensional flow analysis.

A strategy for modeling ground water rebound in abandoned deep mine systems, 2001, Adams R, Younger Pl,
Discharges of polluted water from abandoned mines are a major cause of degradation of water resources worldwide, Pollution arises after abandoned workings flood up to surface level, by the process termed ground water rebound, As flow in large, open mine voids is often turbulent, standard techniques for modeling ground water flow (which assume laminar flow) are inappropriate for predicting ground water rebound. More physically realistic models are therefore desirable, yet these are often expensive to apply to all but the smallest of systems. An overall strategy for ground water rebound modeling is proposed, with models of decreasing complexity applied as the temporal and spatial scales of the systems under analysis increase. For relatively modest systems (area < 200 km(2)), a physically based modeling approach has been developed, in which 3-D pipe networks (representing major mine roadways, etc.) are routed through a variably saturated, 3-D porous medium (representing the country rock). For systems extending more than 100 to 3000 km(2), a semidistributed model (GRAM) has been developed, which conceptualizes extensively interconnected volumes of workings as ponds, which are connected to other ponds only at discrete overflow points, such as major inter-mine roadways, through which flow can be efficiently modeled using the Prandtl-Nikuradse pipe-flow formulation. At the very largest scales, simple water-balance calculations are Probably as useful as any other approach, and a variety of proprietary codes may be used for the purpose

Dispersion, retardation and scale effect in tracer breakthrough curves in karst conduits, 2001, Hauns M. , Jeannin P. Y. , Atteia O. ,
Characteristics of tracer breakthrough curves in karst conduits are examined and compared to results generated using well known equations applied to porous media. The equations of the turbulent dispersion lead to a transport equation similar to the classical advection-dispersion equation for porous media with a slightly different meaning for the dispersion and advection terms. For investigations at the meter length scale, we used a three-dimensional (3-D) computational fluid dynamics (CFD) code to simulate tracer transport in several conduit geometries. The simulations show that turbulent dispersion can be considered as Fickian at a meter length scale of observation and that turbulent dispersivity depends linearly on the average flow velocity in the range of observed velocities. The simulations show that pools induce retardation (tailing of the breakthrough curve) due to flow reversal in eddies. Retardation has a complex relationship with the pool dimensions. Irregularity of the conduit cross-section along the investigated section clearly produces retardation. This is obvious at the meter length scale but may still be visible 10(3) m downstream from the injection point. A transfer function ('black box') approach is used for upscaling from a meter to a 10(3) m length scale. Before applying it to natural examples, the transfer function approach is tested by using the 3-D CFD code and appears to perform well. Several tests, based on numerical, laboratory and held experiments, of conduit segments which includes various dispersive features indicate that retardation tends to be transformed to symmetrical dispersion with distance. At large scale it appears that the dominant dispersion factor is the irregularity of the conduit geometry, which produces an increase in dispersivity with distance ('scale effect'), similar to that observed in porous media. In conclusion this suggests that retardation and high dispersion provide evidence of an irregular conduit, including either numerous dispersive features or large-scale ones (pools for example). Conversely no retardation and moderate dispersion (close to 0.012 m) must result from turbulent Row through a smooth conduit. (C) 2001 Elsevier Science B.V. All rights reserved

Geostatistical and geochemical analysis of surface water leakage into groundwater on a regional scale: a case study in the Liulin karst system, northwestern China, 2001, Wang Y. , Ma T. , Luo Z. ,
The Liulin karst system is typical of hydrogeological systems in northern China, with a group of springs as the dominant way of regional groundwater discharge. Surface water leakage into groundwater has been observed in six sections of the rivers in the study area. To extract hydrogeological information from hydrochemical data, 29 water samples were collected from the system. On a trilinear diagram, most of the groundwater samples are clustered around the surface waters, indicating the effect of leakage on their chemistry. R-mode factor analysis was made on seven variables (Na, Ca, Mg, SO4, Cl, HCO3, and NO3) of the samples and three principal factors were obtained: the F-1 factor is composed of Ca, Mg and SO4, the F-2 of HCO3 and NO3, and the F-3 of Na and Cl. These factors are then used as regionalized variables in ordinary Kriging for unbiased estimates of the spatial variations of their scores. Considering regional hydrogeological conditions, the hydrogeological implications of the spatial distribution of the factor scores as related to the effects of the surface leakage are discussed. To evaluate the geochemical processes, the geochemical modeling code NETPATH was employed. The modeling results: show that mixing commonly occurs in the system and dolomite dissolution is more important than calcite dissolution. Dedolomitization (calcite precipitation and dolomite dissolution driven by anhydrite dissolution) is locally important, in the western flank of the system where the surface water leakage has the least effect.

TRACER: An EXCEL Workbook to Calculate Mean Residence Time in Groundwater by Use of Tracers CFC-11, CFC-12 and Tritium, 2002, Bayari C. Serdar
An EXCEL workbook is presented for calculating the mean residence time of groundwater based on the environmental tracers, tritium, CFC-11 and CFC-12. The program TRACER is written in Visual Basic for Application language and uses piston, exponential, linear, exponential-piston and linear-piston flow types of lumped-parameter models. Input and output data are stored in worksheets and a graph of results that are best fitted to observations is drawn for visual evaluation. Recharge temperature and altitude are used to convert atmospheric partial pressures of CFC-11 and CFC-12 to dissolved concentrations to provide a direct comparison between the models' output and observed data. The model can also be used to check whether an inferred flow type could be valid in the groundwater system being investigated. Other radioactive and gaseous environmental tracers and reactions such as, sorption and degradation can be included either as decay constant or with modifications in the program code. TRACER matches, satisfactorily, the results obtained from other softwares.

HJWFTAC: software for Hantush-Jacob analysis of variable-rate, multiple-extraction well pumping tests, 2002, Fleming Sw, Ruskauff Gj, Adams A,
Analytical well test solutions are a powerful approach to aquifer characterization and the parameterization of comprehensive numerical models. In addition, wellfield drawdown tests, which consist of coordinated pumping and data collection at a suite of monitoring and operating production wells, are of growing significance due to increasing pressures upon groundwater resources and the consequent management and planning requirement for superior hydrogeologic characterization of existing production wellfields. However. few pumping test analysis codes accommodate the multiple extraction wells involved, particularly for more sophisticated analytic aquifer test solutions. We present and demonstrate here a FORTRAN code for analysis of drawdown at a monitor well due to simultaneous variable-rate pumping at multiple independent production wells, which we developed in response to a need to refine an existing numerical, coupled groundwater/surface water resource management model, Spatial and temporal superposition are used to accommodate the typical operational properties of wellfield pumping tests, The software invokes the well-accepted Hantush-Jacob method for semiconfined or 'leaky' aquifers in a forward simulation procedure and effectively assumes homogeneity in applicable aquifer parameters (transmissivity, coefficient of storage, and leakance). Intended for both professionals and students, the code is widely applicable and straightforward to use as written. However, it can be modified with relative ease to use alternative well test solutions and/or formal inverse modeling techniques, or to accommodate spatial hydrogeologic variability. An application to a pumping test conducted in a karst limestone aquifer at the Cross Bar Ranch wellfield in Tampa Bay, Florida, demonstrates the utility of the software. (C) 2002 Elsevier Science Ltd. All rights reserved

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