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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 ground-water mound is a raised area in a water table or other potentiometric surface created by ground-water recharge [22].?

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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 forecasting (Keyword) returned 10 results for the whole karstbase:
Relations between the structure of storage and the transport of chemical compounds in karstic aquifers, 1997, Vaute L. , Drogue C. , Garrelly L. , Ghelfenstein M. ,
Study of the movement of chemical compounds naturally present in the water, or which result from pollution, are examined according to the reservoir structure in karstic aquifers. Structure is represented by a simple geometrical model; slow Row takes place in blocks with a network of low-permeability cracks. The blocks are separated by highly permeable karstic conduits that allow rapid flow, and these form the aquifer drainage system. The karat studied covers 110 km(2). It is fed by an interrupted stream draining a 35 km(2) non-karstic basin, contaminated at the entry to the karst by effluents from a sewage treatment station. The underground water reappears as a resurgence with an annual average flow of approximately 1 m(3) s(-1), after an apparent underground course of 8 km in the karst. Several local sources of pollution (effluent from septic tanks) contaminate the underground water during its course. Sixteen measurement operations were performed at 12 water points, between the interrupted stream and the spring. Some sampling points were at drains, and others were in the low-permeability fissured blocks. Comparison at each point of the concentrations of 14 chemical compounds gave the following results: when pollutant discharge occurs in a permeable zone, movement is rapid in the drainage network formed by the karstic conduits, and does not reach the less permeable fissured blocks which are thus protected; however, if discharge is in a low-permeability zone, the flow does not allow rapid movement of the polluted water, and this increases the pollutant concentration at the discharge, This simple pattern can be upset by a reversal of the apparent piezometric gradient between a block and a conduit during Floods or pumping; this may reverse flow directions and hence modify the movement of contaminants. The study made it possible to site five boreholes whose positions in the karstic structure were unknown, showing the interest of such an approach for the forecasting of the impact of potential pollution.

Ecological incidents in Northern Adriatic Karst (Croatia), 2000, Geres D, Rubinic J, Ozanic N,
In spite of growing efforts to preserve the quality of groundwater resources, accidental pollution is becoming increasingly frequent, resulting in long-lasting impact on the groundwater status. The consequences of ecological accidents are particularly expressed in karst regions, which are caused by the geological properties of the area where the groundwater aquifers are situated, as well as by hydrological circumstances which also influence the dynamic mechanisms of water flow and transportation of pollution in the karst environment. The paper stresses the hydrological component of karst aquifer function and the related role of hydrology in assessment of the hazards caused by accidental pollution and, once the accident has happened, in monitoring the situation and forecasting the possible impact on water resources. The analysis of ecological accidents in the karst has been made, based on the actual examples of accidents involving fuel substances recorded in the Northern Adriatic karst area in Croatia in the period from 1990 to 1998. The basic characteristics of the mechanism of water movement in the karst are presented from the hydrological standpoint, as well as the related risk of rapid transportation of pollutants into the parts of the aquifers used for water supply. The paper also contains proposals for possible approaches to protection of particularly valuable water resources in the karat from accidental pollution occurring in road transport

Forecasting of turbid floods in a coastal, chalk karstic drain using an artificial neural network, 2001, Beaudeau P, Leboulanger T, Lacroix M, Hanneton S, Wang Hq,
Water collected at the Yport (eastern Normandy, France) Drinking Water Supply well, situated on a karst cavity, is affected by surface runoff-related turbidity spikes that occur mainly in winter, In order to forecast turbidity, precipitation was measured at the center of the catchment basin over two years, while water level and turbidity were monitored at the web site. Application of the approach of Box and Jenkins (1976) leads to a linear model that can accurately predict major floods about eight hours in advance, providing an estimate of turbidity variation on the basis of precipitation and mater level variation over the previous 24 hours. However, this model is intrinsically unable to deal with (1) nonstationary changes in the time process caused by seasonal variations of in ground surface characteristics or tidal influence within the downstream past of the aquifer, and (2) nonlinear phenomena such as the threshold for the onset of runoff. This results in many false-positive signals of turbidity in summer. Here we present an alternative composite model combining a conceptual runoff submodel with a feedforward artificial neural network (ANN), This composite model allows us to deal with meaningful variables, the actioneffect of which on turbidity is complex, nonlinear, temporally variable and often poorly described. Predictions are markedly improved, i.e,, the variance of the target variable explained by 12-hour forward predictions increases from 28% to 74% and summer inaccuracies are considerably lowered. The ANN can adjust itself to new hydrological conditions, provided that on-line learning is maintained

Possibilities of geoelectrical and seismo-electrical monitoring in investigations of the karst phenomena, 2002, Bogolubov An, Kamshilin An, Volkova En,
One of the main problems of modern karst investigations is to forecast a place and time of possible depression formation, A solution to this problem requires investigations of karst dynamics by different methods, including geophysical methods. Karst dynamics is determined, in general, by movement of underground waters. At the same time, it is known that electric fields and electric properties of rocks are very sensitive to variations of fluid amounts and their characteristics. Thus, geoelectrical methods of monitoring are useful for investigation of karst dynamics in general and for forecasting karst depressions in particular. Authors have introduced two methods of geophysical monitoring: geoelectrical and seismo-electrical. The main features of instruments and methods of measurement are explained, and the results of the field investigations are shown. The possibilities of the application of these methods to karst dynamics investigations are discussed

Karstification and Groundwater Flow, 2003, Kiraly, L.

One of the principal aims of hydrogeology is to propose a reasonably adequate reconstruction of the groundwater flow field, in space and in time, for a given aquifer. For example, interpretation of the chemical and isotopic composition of groundwater, understanding of the geothermal conditions (anomalies) or forecasting the possible effects of industrial waste disposals and of intensive exploitation nearly always would require the knowledge of the regional and/or local groundwater flow systems such as defined by Toth (1963). The problem of estimating the groundwater flow field in fractured and karstified aquifers is approached within the framework of a conceptual diagram showing the relationship between groundwater flow, hydraulic parameters (aquifer properties and boundary conditions), distribution of voids and geological factors.
Autoregulation between groundwater flow and karst aquifer properties, duality of karst, nested model of geological discontinuities, scale effect on hydraulic parameters and use of numerical finite element models to check the interpretation of the global response of karst springs are some of the subjects addressed by the author. Inferences on groundwater flow regime with respect to the stage of karst evolution can be made only if the hydraulic parameter fields and the boundary conditions are known by direct observations, or estimated by indirect methods for the different types of karst. Practical considerations on the monitoring strategies applied for karst aquifers, and on the interpretation of the global response obtained at karst springs will complete the paper, which throughout reflects the point of view of a hydrogeologist.

Numerical analysis of conduit evolution in karstic aquifers. PhD Thesis, 2003, Annable, W. K.

Fractured and solutionally enhanced carbonate aquifers supply approximately 20 percent of the Worlds potable water supply. Although in rare cases these geologic settings can geochemically evolve into conduits which are of sufficient size to be explored and interpreted by researchers, the majority of the solutionally enlarged networks providing fresh water supplies remain too small to be directly measured. As such, we rely upon indirect hydraulic testing and tracer studies to infer the complexity and size of such aquifers. Because solutionally enhanced (karstic) aquifers have multiple scales of porosity ranging from matrix flow, fracture flow and open channel conduit flow, they are particularly vulnerable to contamination due to the high rates of chemical transport. In this study, a numerical model which solves for the variably-saturated flow, chemically-reactive transport and sediment transport within fractured carbonate aquifers has been developed to investigate the evolution of proto conduits from discrete fractures towards the minimum limits of caves which can be explored. The model results suggest that, although potentiometric surfaces can be of assistance in forecasting the possible locations of proto conduits at depth, many conduits are never detected using conventional observation wells relying upon hydraulic head data. The model also demonstrates the strong dependence in the pattern of vertical jointing on how conduits may evolve: fractures oriented similar to the mean groundwater flow direction show conduits evolving along the vertical fracture orientation; however, vertical fractures that differ significantly from the mean groundwater flow direction have vastly more complex dissolution networks. The transport of fine-grained sediments within the fractures has been shown to reduce the rates of conduit development in all but the highest velocity regions, resulting in simplified conduit networks, but at accelerated dissolution rates. The fully-coupled advective-dispersive and reactive chemistry equations were employed strictly with equilibrium reactions to simulate calcite dissolution. This study further shows that higher order kinetics in the form of the kinetic trigger effect of White (1997) are not required if diffusion between the rock matrix and the fracture surfaces account for multi-component matrix diffusion effects between the evolving conduits and the carbonate rock matrix according to the diffusional characteristics of the fractured rock system at hand.

Forecasting Versus Predicting Solute Transport in Solution Conduits for Estimating Drinking-Water Risks, 2004, Field, Malcolm S.

Contaminant releases in karstic terranes can cause rapid and devastating affects on drinking-water supplies. Because future contaminant releases are likely it is necessary that local water managers develop release scenarios so as to be prepared prior to an actual contaminant release occurring. Release scenarios may be forecasted using appropriate historical data or they may be predicted using selected measured parameters. Forecasting contaminant releases to drinking-water supplies in karstic terranes is best accomplished by conducting numerous tracer tests from each potential source location to each exposure point so that acceptable solute-transport parameters for each solution conduit may be estimated from analyses of the breakthrough curves. Compositing the numerous breakthrough curves and fitting a quintic spline allows development of a single representative breakthrough curve that may then be used to forecast the effects of a release. Predicting contaminant releases is accomplished by combining basic measured field parameters for selected solution conduits in functional relationships for application in solute-transport models. The resulting breakthrough curve and solute-transport parameters can be used to predict the effects of a release. The forecasting and prediction methodologies were tested using a hypothetical release into a solution conduit developed in a karstic aquifer. Both methods were shown to produce reasonably acceptable results. The prediction methodology produced better time-of-travel results and better mass recovery and exposure concentration results than did the forecasting methodology.

Non-stationary spatiotemporal analysis of karst water levels, 2005, Dryden Il, Markus L, Taylor Cc, Kovacs J,
We consider non-stationary spatiotemporal modelling in an investigation into karst water levels in western Hungary. A strong feature of the data set is the extraction of large amounts of water from mines, which caused the water levels to reduce until about 1990 when the mining ceased, and then the levels increased quickly. We discuss some traditional hydrogeological models which might be considered to be appropriate for this situation, and various alternative stochastic models. In particular, a separable space-time covariance model is proposed which is then deformed in time to account for the non-stationary nature of the lagged correlations between sites. Suitable covariance functions are investigated and then the models are fitted by using weighted least squares and cross-validation. Forecasting and prediction are carried out by using spatiotemporal kriging. We assess the performance of the method with one-step-ahead forecasting and make comparisons with naive estimators. We also consider spatiotemporal prediction at a set of new sites. The new model performs favourably compared with the deterministic model and the naive estimators, and the deformation by time shifting is worthwhile

Stochastic modeling of surface stream flow at different time scales: Sangsoorakh karst basin, Iran, 2010, Ghanbarpour M. R. , Abbaspour K. C. , Jalalvand G. , And Moghaddam G. A.
Karstic watersheds are one of the most important areas for water supply. Because the role of groundwater contribution to surface water flow in karst watersheds is not well understood, the commonly used hydrologic models in most regular basins do not provide satisfactory estimates of runoff in karstic regions. This paper uses time-series analysis to model karstic flow in the Sangsoorakh karst drainage basin in the Karkheh subbasin of southwest Iran. The comparison of model forecasting performance was conducted based upon graphical and numerical criteria. The results indicate that autoregressive integrated moving average (ARIMA) models perform better than deseasonalized autoregressive moving average (DARMA) models for weekly, monthly and bimonthly flow forecasting applications in the study area.

Influence of Karst Landscape on Planetary Boundary Layer Atmosphere: A Weather Research and Forecasting (WRF) ModelBased Investigation, 2011, Leeper R. Mahmood R, Quintanar A. I.

Karst hydrology provides a unique set of surface and subsurface hydrological components that affect soilmoisture variability. Over karst topography, surface moisture moves rapidly below ground via sink holes,vertical shafts, and sinking streams, reducing surface runoff and moisture infiltration into the soil. In addition,subsurface cave blockage or rapid snowmelt over karst can lead to surface flooding. Moreover, regionsdominated by karst may exhibit either drier or wetter soils when compared to nonkarst landscape. However,because of the lack of both observational soil moisture datasets to initialize simulations and regional landsurface models (LSMs) that include explicit karst hydrological processes, the impact of karst on atmosphericprocesses is not fully understood. Therefore, the purpose of this study was to investigate the importance ofkarst hydrology on planetary boundary layer (PBL) atmosphere using the Weather Research and ForecastingModel (WRF). This research is a first attempt to identify the impacts of karst on PBL. To model the influenceof karst hydrology on atmospheric processes, soil moisture was modified systematically over the WesternKentucky Pennyroyal Karst (WKYPK) region to produce an ensemble of dry and wet anomaly experiments.Simulations were conducted for both frontal- and nonfrontal-based convection. For the dry ensemble, cloudcover was both diminished downwind of karst because of reduced atmospheric moisture and enhanced slightlyupwind as moist air moved into a region of increased convection compared to control simulations (CTRL).Moreover, sensible (latent) heat flux and PBL heights were increased (decreased) compared to CTRL. Inaddition, the wet ensemble experiments reduced PBL heights and sensible heat flux and increased cloud coverover karst compared to CTRL. Other changes were noted in equivalent potential temperature (ue) andvertical motions and development of new mesoscale circulation cells with alterations in soil moisture overWKYPK. Finally, the location of simulated rainfall patterns were altered by both dry and wet ensembles withthe greatest sensitivity to simulated rainfall occurring during weakly forced or nonfrontal cases. Simulatedrainfall for the dry ensemble was more similar to the North American Regional Reanalysis (NARR) thanCTRL for the nonfrontal case. Furthermore, the initial state of the atmosphere and convective triggers werefound to either enhance or diminish simulated atmospheric responses

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