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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 drainage pattern is a geometric arrangement of stream segments in a drainage system [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 transfer functions (Keyword) returned 10 results for the whole karstbase:
Results of a study about tracing tests transfer functions variability in karst environment, 1997, Doerfliger N.
Artificial tracing tests are often used to simulate migration of a point-source contaminant under various hydrological conditions in karst hydrogeological impact assessment or to define groundwater protection zones. Due to economic reasons, it is rather difficult to carry out adequate tracing tests to determine what are the possible recovery curves over range of discharges at the outlet, are the tracer test results representative of the spring watercatchment being protected ? Our objective was to characterize the tracing-systems in a karst environment by a mean transfer function; such transfer function may be used to predict the breakthrough curve of a point-source contaminant taking into account an error factor. A Jura mean transfer function with + and -95% interval confidence functions can be established and differentiated from the Alps mean transfer function. The use of this transfer function to predict the response of a point-source contaminant requires considerations of water catchment size, thickness or the aquifer and discharge at the outlet. The results of this variability analysis confirm that the transfer functions by themselves may not be used to protect the whole karst spring water catchment, as this one is affected by the heterogeneity of the physical parameters. At the scale of a water catchment, transfer functions are not the major tool to protect the groundwater. But with a multiattribute approach of vulnerability mapping, transfer functions contribute to the development of groundwater protection strategy.

Characteristics of the recharge-discharge relation of the karst aquifer in the background of the Vipava springs (Slovenia), 2000, Petrič, Metka

In the presented research I tried to find answers to the following questions: what the characteristics of the relation between recharge and discharge of the karst aquifer in the background of the Vipava springs are and which conclusions about the functioning of the karst system can be made based on stated relations between its input and output signal. Several different models of the system recharge-discharge were set. For each the conversion of the input signal to the system response was defined by transfer functions, which express conditions and processes in the karst system in mathematical form. Based on the comparison of the suitability of these different models an important influence of vegetation and processes in atmosphere and soil on the quantity of water that actually enters the karst aquifer and is expressed as recharge function was proved. An increase in the accuracy of the simulation was obtained also by the temporal distribution of recharge in fast and slow component, which is in agreement with the double mechanism of the functioning of the system: fast flow through the karst drainage net and longer retardation in the system with storage of water in less permeable zones.

Inverse modeling of the hydrological and the hydrochemical behavior of hydrosystems: Characterization of karst system functioning, 2001, Pinault J. L. , Plagnes V. , Aquilina L. , Bakalowicz M. ,
Inverse modeling of mass transfer characterizes the dynamic processes affecting the function of karst systems and can be used to identify karst properties. An inverse model is proposed to calculate unit hydrographs as well as impulse response of fluxes from rainfall-runoff or rainfall-flux data, the purpose of which is hydrograph separation. Contrary to what hydrologists have been doing for years, hydrograph separation is carried out by using transfer functions in their entirety, which enables accurate separation of fluxes, as was explained in the companion paper [Pinault et al., this issue]. The unit hydrograph as well as impulse response of fluxes is decomposed into a quick and a slow component, and, consequently, the effective rainfall is decomposed into two parts, one contributing to the quick flow (or flux) and the other contributing to the slow flow generation. This approach is applied to seven French karstic aquifers located on the Larzac plateau in the Grands Causses area (in the south of France). Both hydrodynamical and hydrogeochemical data have been recorded from these springs over several hydrological cycles. For modeling purposes, karst properties can be represented by the impulse responses of flow and flux of dissolved species. The heterogeneity of aquifers is translated to time-modulated flow and transport at the outlet. Monitoring these fluxes enables the evaluation of slow and quick components in the hydrograph. The quick component refers to the 'flush flow' effect and results from fast infiltration in the karst conduit network when connection is established between the infiltration and phreatic zones, inducing an increase in water head. This component reflects flood events where flow behavior is nonlinear and is described by a very short transfer function, which increases and decreases according to water head. The slow component consists of slow and fast infiltration, underground runoff, storage in annex-to-drain systems, and discharge from the saturated zone. These components can be further subdivided by measuring chemical responses at the karst outlet. Using Such natural tracers enables the slow component of the unit hydrograph to be separated into preevent water, i.e., water of the reservoir and event water, i.e., water whose origin can be related to a particular rainfall event. These measurements can be used to determine the rate of water renewal. Since the preevent water hydrograph is produced by stored water when pushed by a rainfall event and the event water hydrograph reflects rainwater transfer, separating the two components can yield insights into the characteristics of karst aquifers, the modes of infiltration, and the mechanisms involved in karstification, as well as the degree of organization of the aquifer

Last glacial-Holocene paleoceanography of the Black Sea and Marmara Sea: stable isotopic, foraminiferal and coccolith evidence, 2002, Aksu Ae, Hiscott Rn, Kaminski Ma, Mudie Pj, Gillespie H, Abrajano T, Yasar D,
Multi-proxy data and radiocarbon dates from several key cores from the Black Sea and Marmara Sea document a complex paleoceanographic history for the last ~30[punctuation space]000 yr. The Marmara Sea was isolated from both the Black Sea and the Aegean Sea during glacial periods when global sea-level lowering subaerially exposed the shallow sills at the Straits of Bosphorus and Dardanelles (i.e. lake stage), and reconnected through both straits during interglacial periods, when rise of global sea level breached the shallow sills (i.e. gateway stage). Micropaleontological data show that during the `lake stage' the surface-water masses in both the Marmara Sea and Black Sea became notably brackish; however, during the `gateway stages' there was a low-salinity surface layer and normal marine water mass beneath. Two sapropel layers are identified in the Marmara Sea cores: sapropels M2 and M1 were deposited between ~29.5 and 23.5 ka, and ~10.5 and 6.0 ka, respectively. Micropaleontological and stable isotopic data show that the surface-water salinities were reduced considerably during the deposition of both sapropel layers M2 and M1, and calculation using planktonic foraminiferal transfer functions shows that sea-surface temperatures were notably lower during these intervals. The presence of fauna and flora with Black Sea affinities and the absence of Mediterranean fauna and flora in sapropels M1 and M2 strongly suggest that communication existed with the Black Sea during these times. A benthic foraminiferal oxygen index shows that the onset of suboxic conditions in the Marmara Sea rapidly followed the establishment of fully marine conditions at ~11-10.5 ka, and are attributed to Black Sea outflow into the Marmara Sea since 10.5 ka. These suboxic conditions have persisted to the present. The data discussed in this paper are completely at odds with the `Flood Hypothesis' of Ryan et al. (1997), and Ryan and Pitman (1999)

Composite transfer functions for karst aquifers., 2003, Denicjukic V. , Jukic D.

Composite transfer functions for karst aquifers, 2003, Icjukic V. , Jukic D. ,
Linear transfer functions have been extensively used in hydrological studies. Generally, we support this conclusion: rainfall-runoff models based on the convolution between rainfall rates and a nonparametric transfer function (NTF) are not successful at simulating karst spring discharges during long recession periods. The tails of identified transfer functions have irregular shapes and they are not accurate physical representation of the transport through a karst system. Irregularities are the result of unavoidable errors in input and output time series and simplifications made by considering the system as linear and time invariant. This paper deals with a new form of the transfer functions for karst aquifers, the so-called composite transfer function (CTF). The CTF simulates discharges by two transfer functions adapted for the quick flow and the slow flow hydrograph component modeling. NTF is responsible for the quick flow component. The slow flow component is modeled by a parametric transfer function that is an instantaneous unit hydrograph mathematically formulated and defined from a conceptual model. By using the CTF, the irregular shape of the tail of the identified transfer function can be avoided, and the simulation of long recession periods as well as the simulation of a complete hydrograph becomes more successful. The NTF, the Nash model, the Zoch model and other similar conceptual models can be considered separately as simplified forms of the CTF. The rainfall-runoff model based on the convolution between rainfall rates and the CTF was tested on the Jadro Spring in Croatia. The results of the application are compared with the results obtained by applying NTFs independently. (C) 2003 Elsevier Science B.V. All rights reserved

Trace elements in speleothems. A short review of the state of the art., 2004, Verheyden Sophie
A state of the art of the research on trace elements of speleothems is given. First studies focussed on problems such as the colour of speleothems and the aragonite problem. Insitu studies and studies oriented towards a better understanding of vadose hydrology brought new insights in the controls on trace elemental composition of speleothems. Recent studies deal with microscale analyses and annual and intra-annual chemistry changes. Further in-situ studies should be performed to further differentiate influences, such as climate, soil/weathering and local hydrology in order to better constrain possible transfer functions between the surface and a speleothem.

A frequency domain approach to groundwater recharge estimation in karst, 2004, Jukic D. , Icjukic V. ,
This paper presents an alternative method for determining the values of parameters of a groundwater recharge model. The phreatic zone of a karst aquifer is considered as the linear and time-invariant filter that transforms the input signal of groundwater recharge rates into the output signal of spring discharges. Similarities between transfer functions of total rainfall rates and transfer functions of groundwater recharge rates are the basis for developing the parametric periodogram depending on parameters of a groundwater recharge model. The values of parameters are estimated by minimizing the differences between the parametric periodogram and a periodogram of spring discharges. The approximate Whittle log likelihood function is the criterion for determining the optimal values of the parameters. By using this frequency domain approach, groundwater-balance calculations are avoided so the method can be applied on unexplored karst aquifers when groundwater-balance cannot be achieved without extensive geologic and hydrogeologic investigations. The results of the applications on two springs located in the Dinaric karst area in Croatia are discussed. (C) 2003 Elsevier B.V. All rights reserved

Linear model describing three components of flow in karst aquifers using O-18 data, 2004, Long A. J. , Putnam L. D. ,
The stable isotope of oxygen, 180, is used as a naturally occurring ground-water tracer. Time-series data for 5 180 are analyzed to model the distinct responses and relative proportions of the conduit, intermediate, and diffuse flow components in karst aquifers. This analysis also describes mathematically the dynamics of the transient fluid interchange between conduits and diffusive networks. Conduit and intermediate flow are described by linear-systems methods, whereas diffuse flow is described by mass-balance methods. An automated optimization process estimates parameters of lognormal, Pearson type III, and gamma distributions, which are used as transfer functions in linear-systems analysis. Diffuse flow and mixing parameters also are estimated by these optimization methods. Results indicate the relative proximity of a well to a main conduit flowpath and can help to predict the movement and residence times of potential contaminants. The three-component linear model is applied to five wells, which respond to changes in the isotopic composition of point recharge water from a sinking stream in the Madison aquifer in the Black Hills of South Dakota. Flow velocities as much as 540 m/d and system memories of as much as 71 years are estimated by this method. Also, the mean, median, and standard deviation of traveltimes; time to peak response; and the relative fraction of flow for each of the three components are determined for these wells. This analysis infers that flow may branch apart and rejoin as a result of an anastomotic (or channeled) karst network. Published by Elsevier B.V

Trace elements in speleothems: a short review of the state of the art, 2005, Verheyden, S.

A state of the art of the research on trace elements of speleothems is given. First studies focussed on problems such as the colour of speleothems and the aragonite problem. In-situ studies and studies oriented towards a better understanding of vadose hydrology brought new insights in the controls on trace elemental composition of speleothems. Recent studies deal with microscale analyses and annual and intra-annual chemistry changes. Further in-situ studies should be performed to further differentiate influences, such as climate, soil/weathering and local hydrology in order to better constrain possible transfer functions between the surface and a speleothem.

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