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Enviroscan Ukrainian Institute of Speleology and Karstology

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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 non-point source is 1. any source, other than a point source, which discharges pollutants into air or water [22]. 2. source originating over broad areas, such as areas of fertilizer and pesticide application and leaking sewer systems, rather than from discrete points [22].?

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.
See all featured articles
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 computer (Keyword) returned 71 results for the whole karstbase:
Showing 61 to 71 of 71
Measurement of luminescent banding in speleothems: some techniques and limitations, 2012, Crowell Bryan E. , White William B.

Speleothems, especially flowstone and cylindrical stalagmites, exhibit phosphorescence which is often banded on the scale of a few tens of micrometers. The luminescence bands are paleoclimatic records with a very high temporal resolution. A technique has been developed using a laser source and a high resolution Raman spectrometer with microscope and computer-controlled translation stage for both luminescence profiles and luminescence spectroscopy. Luminescence intensity could be measured as a function of traverse distance with a spatial resolution of 2 – 3 μm. Potential sources of error include loss of intensity due to radiation damage by the laser beam, irregularities, cracks, and inclusions on the polished speleothem surface, and defocusing of the beam along the traverse path.


Wakulla Spring Underwater Cave System, Florida, 2012, Am Ende, Barbara Anne

Wakulla Spring, in the Woodville Karst Plain of western Florida, discharges an average of 11 m3 s−1 from a large, flooded, conduit. The conduit has been mapped with a computer-controlled underwater sonar mapper which provides extremely detailed wall geometry. The presently incomplete, surveyed length of the cave is 6400 meters with a maximum penetration distance of 5488 meters. Water quality has degraded in recent years and is an environmental issue. The cave is an important paleontological site with extensive recovery of mastodon skeletons.


Managing the Survey Information of the Caves of Judbarra / Gregory National Park, Northern Territory, 2012, Kershaw, Bob

The extensive caves in the Judbarra / Gregory National Park have been surveyed using traditional techniques since 1990. The techniques used have developed over time, as new technologies have become available to cavers. With the introduction of hardware such as Global Positioning System handheld units and electronic survey equipment, surveying has become easier, especially in small physically restricting passages. The use of computers and cave data reduction software since the mid-1990s has automated the calculation and plotting of survey shot data. Software that enables the production of maps is time-consuming to learn to use; however, the maps are of high quality, and are easy to maintain and adjust as subsequent expeditions continue to add cave survey data. As the amount of data and the number of users of the data grow, a set of protocols has been developed to ensure the integrity and security of a master data set.


Morphology and 3D images of the Kan-i-Gut mined cave, 2013, Tsibanov V. V. , Filippov A. G. , Dudashvili A. S.

Kan-i-Gut mined cave, located in Kyrgyzstan, is one of the most morphologically complex cavities of mixed genesis. For the first time, a 3D model was developed for this cave by comparative analyses and computer processing of cave maps and mine surveyor plan and profile, obtained from different sources. The methodology of transferring graphical data into digital format is described. Primary morphometric parameters of the mined cave are gathered, and 3D images of its main parts are presented. Essential morphological changes due to vast collapses during the last 50 years were discovered. 


Central concepts of karst hydrology, 2013, Palmer, Arthur N.

The solutional growth of karst features involves a simple mass transfer, in which the mass removed from the walls of a void equals the mass removed in solution by flowing water. Mass removed = volume  rock density, and mass in solution = discharge  solute concentration. Therefore (e.g., in a solution conduit) the rate of volume increase = discharge  gain in dissolved load  time / rock density. Density is essentially con-stant, so conduit size depends only on the cumulative values of discharge, dissolution rate, and time. All three are essential, and all are equally important.
Discharge in a conduit depends on catchment area and water balance; and the distribu-tion of water among all solution conduits depends on hydraulic variables and conduit geometry. Dissolution rate varies with rock type, undersaturation, and solution kinetics, the last of which can be determined by laboratory and field measurements. Together, they provide a tool for quantifying the local geomorphic history.
These relationships seem simple, but applying them quantitatively is complex. This requires a finely divided 2- or 3-dimensional grid in which each segment varies in dis-charge and dissolution rate within each of many small time increments. Computer modelers use this approach to simulate conduit growh; but the results depend on the specific boundary conditions of the model.
It is more challenging to use this concept intuitively to solve real field problems, where the variables are only partly understood. In this case, one must show that the water source, dissolution rate, and available time are all great enough to account for the ob-served solution features. All three variables are closely linked by a web of interactive processes, all of which can be expressed quantitatively. Whether the goal is to under-stand what is already known, or to predict the unknown, this approach provides a solid basis for interpreting karst systems.


GLACIER ICE-CONTACT SPELEOGENESIS, 2013, Lauritzen S. E. Skoglund R. Ø, .

 

The classic hypothesis of G. Horn’s (1935) subglacial speleogenesis as an explanation of the relatively small diameter cave conduits in the Scandinavian marble stripe karst is reviewed. Recent work, including accurate cave mapping and morphological analysis, radiometric dating of cave deposits, chemical kinetics experiments and computer simulations have challenged the old theory. Scandinavia has relatively small caves that often have surprisingly high ages, going beyond the limit of Th/U dating. The high ages are apparently compensated by correspondingly slow wall retreat rates in the icecontact regime, and longer periods when the caves were inactive. Ice-contact speleogenesis varied in time and space, in pace with waxing and waning of wet-based ice. Maze or labyrinth morphology appears as a characteristic feature of caves ascribed to these processes.


Effects of sinuosity factor on hydrodynamic parameters estimation in karst systems: a dye tracer experiment from the Beyyayla Sinkhole (Eskişehir, Turkey), 2013, Aydin H. , Ekmekci M. , Soylu M. E.

The sinuosity factor (SF) is a critical value in karst systems in terms of estimating their hydrodynamic parameters including groundwater velocity, coefficient of dispersion, etc., through dye tracer experiments. SF has been used in a number of different dye tracer experiments in karstic systems to estimate a representative flow path. While knowing SF is crucially important in the estimation of hydrodynamic parameters, its calculation is associated with significant uncertainty due to the complexity of subsurface karstic features. And yet, only a few studies have discussed its uncertainties, which might lead some errors in estimation of hydrodynamic parameters from dye tracer experiment. In this study, dye tracer experiments were conducted in two consecutive years (2003 and 2004) representing low and high flow conditions in the Beyyayla sinkhole (Eskişehir, Turkey) where the flow path is well known. Uranine was used in experiments as a tracer and QTRACER computer program was used to determine the hydrodynamic properties of the Beyyayla karst system as well as to gain insights into the effects of SF from dye tracer experiments on estimated parameters. The results showed that the breakthrough curve follows a unimodal and a bimodal distribution in low and high flow conditions, respectively. These different distributions stem from the water transport mechanisms, where velocities were calculated as 58.2 and 93.6 m h−1 during low and high flow conditions observed in a spring emerging from the south side of the studied system. The results also show that the coefficient of dispersion, Reynolds number, and Peclet number increased and longitudinal dispersivity decreased with the higher flow rate. Furthermore, the estimated parameters did not vary with either the flow conditions or the tracer transit time, but they have shown some variations with SF. When SF was increased by 50 %, a change in these parameters was obtained in the range of 50–125 %.


Niphargus: a silicon band-gap sensor temperature logger for high-precision environmental monitoring. , 2015,

A temperature logger, named “Niphargus”, was developed at the Geological Survey of Belgium to monitor temperature of local natural processes. It has a sensitivity of the order of a few hundredths of degrees on temperature variability in open air, caves, soils and river environment. The newly developed instrument uses a state-of-the-art band-gap silicon temperature sensor with integrated digital output. This sensor reduces the risk of drift associated with thermistor-based sensing devices, especially in humid environments. The Niphargus is designed to be highly reliable, low-cost and powered by a single lithium cell with up to several years autonomy, depending on the sampling rate and environmental conditions. A batch of Niphargus loggers was also compared to a precision thermistor to assess absolute temperature accuracy. Further characterization came from two field case studies in Belgium: monitoring of a mineralized water stream near the town of Spa and air temperature monitoring inside Han-sur-Lesse cave.


Niphargus: a silicon band-gap sensor temperature logger for high-precision environmental monitoring. , 2015,

A temperature logger, named “Niphargus”, was developed at the Geological Survey of Belgium to monitor temperature of local natural processes. It has a sensitivity of the order of a few hundredths of degrees on temperature variability in open air, caves, soils and river environment. The newly developed instrument uses a state-of-the-art band-gap silicon temperature sensor with integrated digital output. This sensor reduces the risk of drift associated with thermistor-based sensing devices, especially in humid environments. The Niphargus is designed to be highly reliable, low-cost and powered by a single lithium cell with up to several years autonomy, depending on the sampling rate and environmental conditions. A batch of Niphargus loggers was also compared to a precision thermistor to assess absolute temperature accuracy. Further characterization came from two field case studies in Belgium: monitoring of a mineralized water stream near the town of Spa and air temperature monitoring inside Han-sur-Lesse cave.


Procedural Modeling of Cave-like Channels, 2015, Pytel Alex, Mann Stephen

Hydraulic erosion that takes place underground leads to the formation of complex channel networks whose morphology emerges from the dynamic behavior of each channel, based on the presence of other channels nearby. Our approach to the problem of modeling such channel networks for computer graphics application involves a self-organized model of channel development and a two-stage simulation for constructing the geometry of the channels. By emphasizing self-organization of flow and pressure, our simulation is able to reproduce several types of channel behavior known from hydrogeomorphology, such as tributary capture.


A Three-dimensional Statistical Model of Karst Flow Conduits, 2016, Boudinet, P

It already exists several three-dimensional models dealing with groundwater circulation in karst systems. However, few of them are able either to give a large scale prediction of the repartition of the flow conduits or to make a comparison with real field data. Therefore, our objective is to develop a three-dimensional model about the early formation of karst flow conduits and to compare it with actual field data. This geometric and statistical model is based on percolation and random walks. It is computational and can be run on a personal computer. We examine the influence of fissures (joints and bedding planes) of variable permeability and orientations on the development or early flow conduits. The results presented here correspond to computations up to 2015. Because of long runtimes, we focused on some particular stereotypical situations, corresponding to some particular values of the parameters. Regarding the conduit patterns, the opening and directions of fissures have the same qualitative influence in the model than in actual systems. Two other predictions in good accordance with real karst are that flow conduits can either develop close to the water table or deeper, depending on the distribution of permeable fissures; and that, when viewed in the horizontal plane, conduits don't always develop close to the straight line between inlet and outlet. From a quantitative point of view, in the case of weak dips, our model predicts a realistic relationship between the stratal dip, the length of the system and the averaged depth of the conduits. Eventually, we show that the repartition of conduits depends not only on obvious geometrical parameters such as directions and sizes, but also also on other quantities difficult to measure such as the probability of finding open fissures. The lack of such data doesn't enable, at the present time, a whole comparison between model and reality.


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