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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 potential evapotranspiration is evapotranspiration occurring under adequate soilmoisture supply at all times for given temperature and humidity conditions [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 pipe flow (Keyword) returned 23 results for the whole karstbase:
Showing 1 to 15 of 23
Geophysical applications of heat and mass transfer in turbulent pipe flow, 1971, Wigley T. , Brown C. ,

HYDROLOGIC RESPONSE OF A KARST WATERSHED, 1994, Felton Gk,
A ground water catchment was instrumented as a karst hydrology and water quality laboratory to develop long-term flow and water quality data. This catchment located in Woodford and Jessamine Counties in the Inner Bluegrass, Central Kentucky encompasses approximately 1620 ha, 40 water wells, over 400 sinkholes, 2 karst windows, and 1 sinking stream. The land uses consist of approximately 59% beef pasture, horse farm, and golf course; 16% row crops; 6% orchard; 13%forest; and 6% residential. The instrumentation consisted of a recording rain gage, an H-flume, a water stage recorder, and an automated water sampler. Flow data for 312 days were analyzed, and a peak flow rate prediction equation, specific to this catchment, was developed Recession curves were analyzed and found to be of two distinct mathematical forms, log curves and exponential curves. Prediction equations were good for the log-type recession curve and fair for the exponential-type recession curve. For the exponential recessions, the peak flow rate was found to be bimodally distributed The recession events were classified as either high flow or low flow, with the point of separation at 113 L/s. It was hypothesized that the flow system was controlled by pipe flow above 113 L/s and by open channel flow below 113 L/s. Subsequent analysis resulted in adequate prediction for the low flow events. Explained variation associated with the high flow events was low and attributed to storage in the karst system that was not incorporated into the predictor equation

Determination of transmissivity from specific capacity tests in a karst aquifer, 1997, Mace R. E. ,
Specific capacity tests are useful for estimating transmissivity in aquifers that have few good-quality pump tests, In karst aquifers, this has been done by (1) correcting specific capacity for turbulent well loss and using analytical relationships between transmissivity and specific capacity, and (2) correcting specific capacity for well loss and deriving an empirical relationship between transmissivity and specific capacity. This study focuses on the uncertainties of estimating well loss and presents an empirical relationship between transmissivity and uncorrected specific capacity for a karst aquifer. Well loss is difficult to estimate without good-quality step-drawdown tests. Pipe-flow theory tends to underestimate well loss, and an empirical relationship between specific capacity and well-loss constant has a large prediction interval that leads to well loss exceeding measured drawdown, To overcome uncertainties of estimating web loss, transmissivity and uncorrected specific capacity were related for aquifer tests from the Edwards aquifer in Texas, The resulting best-fit line is T = 0.76(S-c)(1.08) for T and S-c in m(2) d(-1), with a coefficient of determination, R-2, Of 0.89 and a 95-percent prediction interval spanning approximately 1.4 log cycles, Though the prediction interval is large, approximate but useful estimates of transmissivity can be determined because the relationship extends over five orders of magnitude from 1 to 100,000 m(2) d(-1). The relationship is applicable in at least one other karst aquifer and therefore may be useful for others

Simulation of the development of karst aquifers by using a pipe flow model coupled to a continuum model, 2, Model verification and sensitivity analysis., 1998, Clemens T. , Huckinghaus D. , Sauter M. , Liedl R. , Teutsch G.

Characterisation of gypsum aquifers using a coupled continuum-pipe flow model, 2000, Birk S. , Liedl R. , Sauter M.

Modelling karst aquifer genesis using a coupled continuum-pipe flow model, 2000, Sauter M. , Liedl R.
This contribution presents a modeling approach for the simulation of karst aquifer genesis during geologic time periods. The approach used here is based upon a hydraulic coupling of a pipe network to a continuum in order to represent the well-known duality of karst aquifer flow systems. In addition, the growth of the karst conduits due to carbonate dissolution can be simulated so that a feedback mechanism with respect to the hydraulic properties of the pipe network is established. The model is applied to some typical scenarios of karst aquifer genesis, i. e. the evolution of a dendritic tube system and of a maze cave network. It is found that the model results can successfully reproduce the basic features of karst development, e. g. the development of maze caves in a carbonate aquifer which is covered by a sandstone caprock.

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

Simulating time-varying cave flow and water levels using the Storm Water Management Model, 2002, Campbell Cw, Sullivan Sm,
The Storm Water Management Model (SWMM) is an Environmental Protection Agency code used to estimate runoff through storm water drainage systems that include channels, pipes, and manholes with storage. SWMM was applied to simulate flow and water level changes with time for a part of Stephens Gap Cave in Jackson County, Alabama. The goal of the simulation was to estimate losses from a surface stream to the cave. The cave has three entrances that can remove water from the surface stream. These entrances connect through several passages to an 8-m (27-ft) high waterfall in a dome room. After a storm, the walls of this dome room had leaves on the wall as high as 4.6 m (15 ft) above the floor. The model showed that the height of the leaves did not represent a water level that could have occurred following any recent storm.Campbell, Livingston and Garza in 1997 developed the CLG model to estimate losses from karst surface streams. This model treats losses as pipe flow from a reservoir and gives the loss flow rate as ~h0.5 where h is the depth of flow in the surface stream. Losses to Stephens Gap Cave calculated with SWMM varied as h1.8. This depth dependence is more characteristic of flow over a weir than of pipe flow.The SWMM-calculated losses to Stephens Gap Cave showed no hysteresis, that is, the rising and falling limbs of the stage-discharge plot followed the same curve. Loss curves with significant hysteresis are difficult to simulate with simple models such as CLG or a weir flow model. However, an SWMM model of a simple hypothetical cave demonstrated that storage in Stephens Gap Cave is far below that required to cause hysteresis. Losses from many karst surface streams can probably be adequately estimated with a calibrated weir flow model. The utility of SWMM for analyzing cave flows was established. SWMM produced stable solutions with very low continuity errors for this cave

Modeling of karst aquifer genesis: Influence of exchange flow, 2003, Bauer S, Liedl R, Sauter M,
[1] This paper presents a numerical model study simulating the early karstification of a single conduit embedded in a fissured system. A hybrid continuum-discrete pipe flow model (CAVE) is used for the modeling. The effects of coupling of the two flow systems on type and duration of early karstification are studied for different boundary conditions. Assuming fixed head boundaries at both ends of the conduit, coupling of the two flow systems via exchange flow between the conduit and the fissured system leads to an enhanced evolution of the conduit. This effect is valid over a wide range of initial conduit diameters, and karstification is accelerated by a factor of about 100 as compared to the case of no exchange flow. Parameter studies reveal the influence of the exchange coefficient and of the hydraulic conductivity of the fissured system on the development time for the conduit. In a second scenario the upstream fixed head boundary is switched to a fixed flow boundary at a specified flow rate during the evolution, limiting the amount of water draining toward the evolving conduit. Depending on the flow rate specified, conduit evolution may be slowed down or greatly impaired if exchange flow is considered

Hydraulic boundary conditions as a controlling factor in karst genesis: A numerical modeling study on artesian conduit development in gypsum., 2003, Birk S. , R. Liedl. , M. Sauter. , Teutsch G.
doi:10.1029/2002WR001308.A coupled continuum-pipe flow model is employed to simulate the development of karst conduits in an artesian setting, where aggressive water flows upward from an insoluble aquifer into a gypsum unit. Speleogenetic processes and controlling parameters are identified first for single conduit development. It is demonstrated that transient flow from the conduit into the surrounding fissured system of the rock enhances solutional conduit enlargement. Moreover, single conduit development is found to be highly sensitive to variations in initial diameter and hydraulic gradient. Simulating the solutional enlargement of pipe networks reveals that these two factors determine the resulting conduit pattern. Structural preferences are found to be essential for horizontal conduit development, otherwise flow paths are solely enlarged in vertical direction following the hydraulic gradient. Hydraulic gradients that increase with time can limit the extension or completely inhibit the development of horizontal caves even if lateral conduit development was structurally preferred.

Hydraulic boundary conditions as a controlling factor in karst genesis: A numerical modeling study on artesian conduit development in gypsum - art. no. 1004, 2003, Birk S, Liedl R, Sauter M, Teutsch G,
A coupled continuum-pipe flow model is employed to simulate the development of karst conduits in an artesian setting, where aggressive water flows upward from an insoluble aquifer into a gypsum unit. Speleogenetic processes and controlling parameters are identified first for single conduit development. It is demonstrated that transient flow from the conduit into the surrounding fissured system of the rock enhances solutional conduit enlargement. Moreover, single conduit development is found to be highly sensitive to variations in initial diameter and hydraulic gradient. Simulating the solutional enlargement of pipe networks reveals that these two factors determine the resulting conduit pattern. Structural preferences are found to be essential for horizontal conduit development, otherwise flow paths are solely enlarged in vertical direction following the hydraulic gradient. Hydraulic gradients that increase with time can limit the extension or completely inhibit the development of horizontal caves even if lateral conduit development was structurally preferred

Simulation of the development of karst aquifers using a coupled continuum pipe flow model - art. no. 1057, 2003, Liedl R. , Sauter M. , Huckinghaus D. , Clemens T. , Teutsch G. ,
[1] This paper is intended to provide insight into the controlling mechanisms of karst genesis based on an advanced modeling approach covering the characteristic hydraulics in karst systems, the dissolution kinetics, and the associated temporal decrease in flow resistance. Karst water hydraulics is strongly governed by the interaction between a highly conductive low storage conduit network and a low-conductive high-storage rock matrix under variable boundary conditions. Only if this coupling of flow mechanisms is considered can an appropriate representation of other relevant processes be achieved, e.g., carbonate dissolution, transport of dissolved solids, and limited groundwater recharge. Here a parameter study performed with the numerical model Carbonate Aquifer Void Evolution (CAVE) is presented, which allows the simulation of the genesis of karst aquifers during geologic time periods. CAVE integrates several important features relevant for different scenarios of karst evolution: (1) the complex hydraulic interplay between flow in the karst conduits and in the small fissures of the rock matrix, (2) laminar as well as turbulent flow conditions, (3) time-dependent and nonuniform recharge to both flow systems, (4) the widening of the conduits accounting for appropriate physicochemical relationships governing calcite dissolution kinetics. This is achieved by predefining an initial network of karst conduits ('protoconduits'') which are allowed to grow according to the amount of aggressive water available due to hydraulic boundary conditions. The increase in conduit transmissivity is associated with an increase in conduit diameters while the conductivity of the fissured system is assumed to be constant in time. The importance of various parameters controlling karst genesis is demonstrated in a parameter study covering the recharge distribution, the upgradient boundary conditions for the conduit system, and the hydraulic coupling between the conduit network and the rock matrix. In particular, it is shown that conduit diameters increase in downgradient or upgradient direction depending on the spatial distribution (local versus uniform) of the recharge component which directly enters the conduit system

Conduit properties and karstification in the unconfined Floridan Aquifer, 2004, Screaton E. , Martin J. B. , Ginn B. , Smith L. ,
Exchange of water between conduits and matrix is an important control on regional chemical compositions, karstification, and quality of ground water resources in karst aquifers. A sinking stream (Santa Fe River Sink) and its resurgence (River Rise) in the unconfined portion of the Floridan Aquifer provide the opportunity to monitor conduit inflow and outflow. The use of temperature as a tracer allows determination of residence times and velocities through the conduit system. Based on temperature records from two high water events, flow is reasonably represented as pipe flow with a cross-sectional area of 380 m(2), although this model may be complicated by losses of water from the conduit system at higher discharge rates. Over the course of the study year, the River Rise discharged a total of 1.9 x 10(7) m(3) more water than entered the River Sink, reflecting net contribution of ground water from the matrix into the conduit system. However, as River Sink discharge rates peaked following three rainfall events during the study period, the conduit system lost water, presumably into the matrix. Surface water in high flow events is typically undersaturated with respect to calcite and thus may lead to dissolution, depending on its residence time in the matrix. A calculation of local denudation is larger than other regional estimates, perhaps reflecting return of water to conduits before calcite equilibrium is reached. The exchange of matrix and conduit water is an important variable in karst hydrology that should be considered in management of these water resources

A STEADY STATE HYDRAULIC MODEL OF A KARST AQUIFER, 2007, Turk, J.

It is known, that 90 % or even more of underground water flows through large conduits. Restrictions and siphons represent only small percentage of karstic aquifer. But because of them, con­duits, which transmit water, are only partly accessible. Difficult access is a reason why many water transmissions have not been explored yet. Because of this, geometry and length of all under­ground conduits is not known, it can be only predicted. In such a case processes of water flow in karstic conditions are more easily predictable by modeling. Basic physical models are usu­ally used. They are based on the conduit permeability of karst water. We assume conduits with different dimensions, smaller usually presenting areas of full pipe flow (under pressure) and larger open channel flow. We were interested in the hydraulic conditions, when does the change from open channel to full pipe flow occur and when does underground flow from main conduit divide into two neighbouring conduits. The response of a karst aquifer to a flood pulse was not studied in our model, but we observed its behaviour during a constant increase of re­charge into the karstic underground.


Conduit evolution in deep-seated settings: Conceptual and numerical models based on field observations, 2008, Rehrl C. , Birk S. , Klimchouk A. B.

To examine the interrelation between hydrogeological environment and conduit development in deep-seated settings, a conceptual model is tested by numerical modeling. Based on field observations, simplified model settings are designed and crucial parameters are varied. A coupled continuum-pipe flow model is employed for simulating conduit development within the soluble unit of a multilayer aquifer system. In agreement with field observations, the evolving cave patterns are characterized by pronounced horizontal passages and multiple vertical conduits at the bottom of the soluble unit but only few at the top. The frequency distribution of conduit diameters is found to be bimodal if the permeability of the rock formation is sufficiently high to allow competitive conduit development governed by the feedback between increasing flow and dissolution rates. This feedback, however, is suppressed in low-permeability formations. As a consequence, conduit development is uniform rather than competitive.


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