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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 point-bar deposit is sedimentation on the inside of a meander loop of a river or stream channel [16].?

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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 accuracy (Keyword) returned 49 results for the whole karstbase:
Showing 16 to 30 of 49
Meaning and representation of boundaries in karst type maps, 2001, Angsü, Sser Stephan

The paper deals with boundaries in general and specifically with boundaries in large scale karst type maps. On the basis of a differentiation into dependent and independent variables a methodological attempt is presented, allowing to integrate information about the boundary type and the boundary accuracy. This additional information should help karst researchers answering genetic questions.

Revising the Karst Map of the United States, 2002, Veni, G.
The production of the recently published Living with karst: Afragile foundation required a map showing the distribution of karst in the United States. William Davies et al. (1984) produced the last such map. I used their work as the basis in developing a revised US karst map, but delineated karst primarily on lithology rather than cave lengths. The categories are: exposed and buried carbonate and evaporite karst, and volcanic and unconsolidated pseudokarst. The new US karst map updates the previous map with data from more detailed regional karst maps. Scale and information availability limited the accuracy of the new map. Buried evaporites and unconsolidated pseudokarst are underrepresented due to insufficient delineation. I had to interpolate from available information to adjust for discrepancies due to different map projections and differences between maps. The new US karst map improves on earlier versions but is still incomplete and of low precision in some areas. Production of detailed karst maps with drainage basins and other land management factors is best left to state agencies. The US Geological Survey is developing a new US karst map and the NSS Section of Cave Geology and Geography is assisting with that effort. Uniform standards need to be established for definitions, scale, and map projections. Section members include the countrys most knowledgeable karst geoscientists and they play key roles in developing an accurate and definitive US karst map.

Modes de positionnement topographique et lectromagntique dun siphon. Exemple du Qattine Azar (Liban), 2002, Courbon, Paul
Topographical and electromagnetic positioning of a deep sump: Qattine Azar (Lebanon) - Wasting, pollution, climatic modifications, urbanisation and demographic explosion will generate a serious water scarcity in many countries, among them, the Middle East. In Lebanon, after the discovery of an important underground river, is established a water impounding project, needing a 280 meters drilling through limestone. The author describes the topographic method used to survey the cave and to set up the future drilling. The survey has been confirmed by an electromagnetic positioning ARCAS (radiolocation) perfected by Joan Erra. The accuracy of the two determinations is estimated.

Cambial growth of Swietenia macrophylla King studied under controlled conditions by high resolution laser measurements, 2003, Dunisch O, Schulte M, Kruse K,
The kinetics of phloem and xylem formation of two-year-old plants of Swietenia macrophylla King (true mahogany) was studied in a model system along the shoot circumference (experiment 1) and along the shoot axis (experiment 2). The radius increment of the shoot was registered by high resolution laser measurements (accuracy: 2 mum) in a spatial resolution of 7.8 to 41.3 mum along the stem circumference and 1.5 mm along the stem axis. The temporal resolution of the measurements was 2 s in experiment 1 and 20 s in experiment 2. The radius increment of the shoot detected by the laser measurements was predominately due to the radial enlargement of the phloem and xylem derivatives. On the phloem side the reinitiation of radial cell enlargement after a cambial dormancy occurred first in sieve tubes with contact to ray parenchyma cells, while on the xylem side the radial cell enlargement of vessels and paratracheal parenchyma was induced almost simultaneously along the shoot circumference. In the phloem and xylem derivatives, which were formed first after the cambial reactivation, radial cell enlargement was induced almost simultaneously along the shoot axis. In more advanced phases of phloem and xylem formation, radial cell enlargement of phloem and xylem derivatives was induced shoot downwards with a rate of approximately 13 mm per min. The mean rate of radial cell enlargement of the phloem and xylem derivatives was 2.26 and 4.37 mum per min, respectively. These findings suggest that the kinetics of cambial growth of tropical tree species differ significantly from kinetics observed in trees from temperate regions. The laser measurements might provide a useful experimental approach for studies of cambial activity in situ

Inversion strategy in crosshole radar tomography using information of data subsets, 2004, Becht A, Tronicke J, Appel E, Dietrich P,
Detecting discrete anomalies, such as cavities or tunnels, is an important application of crosshole radar tomography. However, crosshole tomographic inversion results are frequently ambiguous, showing smearing effects and inversion artifacts. These ambiguities lead to uncertainties in interpretation; hence, the size and position of anomalies can only be interpreted with limited accuracy and reliability. We present an inversion strategy for investigating discrete anomalies with crosshole radar tomography. In addition to the full traveltime data set, we use subsets of specified ray-angle intervals for tomographic inversion. By analyzing inversion results from different ray-angle intervals, a more accurate interpretation of anomalies is possible. The second step of our strategy is to develop a good inhomogeneous starting model from joint interpretation of the inversion results from different subsets. The third step is to invert the full data set using this new starting model and to evaluate the inversion results by analyzing the distributions of mean square traveltime residuals with respect to the ray angles. We use a synthetic model with two discrete anomalies located roughly at the same depth to demonstrate and evaluate our approach. This inversion strategy is also applied to a field data set collected to investigate karst cavities in limestone. From the inversion results of both examples, we show that horizontal smearing of anomalies can be reduced by eliminating near-horizontal rays. A good starting model can be obtained based on the joint interpretation of the inversion results of the different subsets; it leads to a high-resolution final image of the full data set

Lithuanian karst region rivers' water ecology: hydrochemical and hydrobiological evaluation, 2004, Tumas R. ,
The Lithuanian karst region covers about 1000 km(3) in the northern part of the country. This is the most vulnerable area from a pollution point of view. The structure of the total dissolved solids (TDS) shows that the flow of rivers in the karst region is from hydraulically interconnected aquifers. For the last decade (1991-2000) TDS has varied considerably, from 529 to 732 mg/l. The predominant sources of nitrogen and phosphorus within the headwaters of the monitored rivers were diffuse and agricultural in nature. Downstream from the towns nitrogen and especially phosphorus showed both diffuse and point source signals. Contributions of point sources to the stream pollution by nutrients prevail. The time series of monthly dissolved oxygen (O-2) in the main karst region river - the Musa - shows the existence of multiplicative seasonality. The trend cycle (1991-1999) shows low levels of dissolved oxygen in 1991-1993, with a similar fluctuation in 1994, 1995 and 1996 (due to point pollution from the town of Siauliai) and a gradually improving situation since 1997. The general multiplicative trend of dissolved oxygen in the lower reaches of the Musa river (near the border with Latvia) is decreasing (within the accuracy limits). The abundance and species of zoo benthos are suitable criteria (biotic index - 131) for evaluation of a river's biological water quality. Zoo benthos demonstrates tolerances that vary among species, the oxygen regime and the pollution with nitrogen. The best living conditions for invertebrates are in the riverhead of the karst region rivers - 131 = 5.62-6.74 (1991-1999), where pollution with nutrients is caused mostly by agricultural activity. Rare and asynchronous data of biological water quality shows up tendencies that invertebrates prefer less contaminated reaches of rivers

High-accuracy graphic representation of underground karst features and formations during cave mapping, 2004, Szunyogh Gá, Bor

We attempt to develop a new method of cave mapping, which would be superior in terms of the amount and quality of the documented information, relative to the "standard" methods of cave survey. The method envisages that everything that can be seen in the cave which is being surveyed, e.g., corrosional features, cave formations, water bodies, fallen rock blocks, fractures in cave walls, artificial (engineering) structures, etc., must be represented on the map. The method employs the traditional system of map symbols; the accuracy of the produced map, however, approaches the accuracy of the engineering survey maps. The maps accurately render positions, shapes and dimensions of cave features: for example all stalagmites with diameters greater than ca. 10 cm, and all rock blocks with linear sizes exceeding 0.5 m are shown on the maps individually. In the report we will elaborate on the most important aspects of this mapping method, including stages of survey and mapping, system of drawing, map symbols.

Measurement of pH for field studies in karst areas., 2005, Sasowsky I. D. , Dalton C. T.
The determination of pH in karst waters is important for evaluating such chemical processes as cave growth, speleothem deposition, and overall water chemistry. Relatively small errors in pH readings can result in significant misinterpretations of the chemical processes taking place. For example, a pH error of 0.5 units would produce a correlative error in SIcalcite of 0.5. To ensure accuracy, pH must be measured in the field, but the conditions in karst settings make this hard to accomplish, and there is minimal published guidance available. Actions that help to improve data quality include: use of a good meter/electrode (accurate to 2 decimal places), careful preparation before field activities, cautious transport of instruments, frequent calibration, measurement in a beaker (not the water body), and allowance of time for equilibration. Instrumentation that allows measurement of very small samples, samples in wells, or continuous monitoring are available, but are more expensive and usually not as accurate.

Test of a distributed modelling approach to predict flood flows in the karst Suoimuoi catchment in Vietnam, 2005, Liu Y. B. , Batelaan O. , De Smedt F. , Huong N. T. , Tam V. T. ,
The major obstacles for modelling flood processes in karst areas are a lack of understanding and model representations of the distinctive features and processes associated with runoff generation and often a paucity of field data. In this study, a distributed flood-modelling approach, WetSpa, is modified and applied to simulate the hydrological features and processes in the karst Suoimuoi catchment in northwest Vietnam. With input of topography, land use and soil types in a GIS format, the model is calibrated based on 15 months of hourly meteorological and hydrological data, and is used to Simulate both fast surface and conduit flows, and groundwater discharges from karst and non-karst aquifers. Considerable variability in the simulation accuracy is found among storm events and within the catchment. The simulation results show that the model is able to represent reasonably well the stormflows generated by rainfall events in the study catchment

The use of microgravity for cavity characterization in karstic terrains, 2005, Styles P. , Mcgrath R. , Thomas E. , Cassidy N. J. ,
Microgravity is the interpretation of changes in the subsurface density distribution from the measurement of minute variations in the gravitational attraction of the Earth. As a technique, it is particularly suited to the investigation of subsurface structures, mapping of geological boundaries and, most importantly in this case, the location and characterization of voids or cavities. Gravity variations due to the geological/petrophysical changes associated with fracturing and changes in pore composition are superimposed upon much larger variations due to elevation, latitude, topography, Earth tides and regional geological variations. However, these external changes can be modelled or monitored with sufficient accuracy to be removed from the data. With the recent development of high-resolution instruments, careful field acquisition techniques and sophisticated reduction, processing and analysis routines, anomalies as small as 10 microgal can be detected and interpreted effectively. This paper describes the state-of-the-art' application of the microgravity technique for the detection and characterization of karstic cavities in a variety of limestone terrains, including the Carboniferous Limestone of the United Kingdom and Eire and the coral limestones of the Bahamas. The case study examples show how the recorded gravity anomalies have revealed the location of density variations associated with underground cave systems and, ultimately, provided information on their depths, shapes and morphology from a combined analysis of their spectral content, characteristic gradient signatures and modelling responses. In addition, mass deficiencies have been estimated, directly from the anomaly map, by the use of Gauss's theorem without any prior knowledge of the exact location, or nature, of the causative bodies

The effect of binocular vision disorders on cave surveying accuracy, 2006, Dougherty, Mark
Binocular vision disorders such as heterophoria and hyperphoria are relatively common. This paper shows that, if a cave survey team does not take careful account of the possibility of one or more of its members suffering from such a disorder, very serious errors can occur. Theoretical and empirical evidence is presented. The likely magnitude of these errors implies that BCRA grade 5 cannot be achieved unless surveyors check for or, if necessary, correct for binocular vision disorders. Various techniques to eliminate such errors are explained and compared. Finally, a recommendation is made concerning an additional clause to the notes that accompany the BCRA cave surveying grade definitions. To achieve BCRA grade 5, the possibility of binocular vision disorders must be taken into account.

Correlating specific conductivity with total hardness in limestone and dolomite karst waters, 2006, Krawczyk W. E. , Ford D. C. ,
Under field conditions modern digital conductivity meters give standardized, rapid and reproducible measurements. Here we investigate the accuracy of their estimates of the composition of karst waters, as total hardness (TH, as mg/L CaCO3) for limestone and dolomite. These are the fundamental measures of process in carbonate karst geomorphology. PHREEQC theoretical curves for the dissolution of pure calcite/aragonite and dolomite in water at 25 degrees C are compared with water analyses from karst studies worldwide. Other principal ions encountered are sulphates, nitrates and chlorides (the 'SNC' group). From carbonate karsts, 2309 spring, well and stream samples were divided into uncontaminated (SNC < 10%), moderately contaminated (10 < SNC < 20%), and contaminated (SNC > 20%) classes. Where specific conductivity (SpC) is less than 600 mu S/cm, a clear statistical distinction can be drawn between waters having little contamination and substantially contaminated waters with SNC > 20%. As sometimes claimed in manufacturers' literature, in 'clean' limestone waters TH is close to 1/2SpC, with a standard error of 2-3 mg/L. The slope of the best-fit line for 1949 samples covering all SNC classes where SpC < 600 mu S/cm is 1.86, very close to the 1.88 obtained for clean limestone waters; however, the value of the intercept is ten times higher. The regression line for clean limestone waters where SpC > 600 mu S/cm helps to distinguish polluted waters from clean waters with possible endogenic sources of CO2. In the range 250 < SpC < 600 mu S/cm, dolomite waters can be readily distinguished from limestone waters. Copyright (C) 2005 John Wiley & Sons, Ltd

Using 2D inversion of magnetic resonance soundings to locate a water-filled karst conduit, 2006, Boucher M, Girard Jf, Legchenko A, Baltassat Jm, Dorfliger N, Chalikakis K,
SummaryA new methodology for magnetic resonance sounding (MRS) data acquisition and interpretation was developed for locating water-filled karst cavities. This methodology was used to investigate the Ouysse karst system in the Poumeyssens shaft in the Causse de Gramat (France). A new 2D numerical MRS response model was designed for improved accuracy over the previous 1D MRS approach. A special survey performed by cave divers confirmed the accuracy of the MRS results. Field results demonstrated that in favourable conditions (a low EM noise environment and a relatively shallow, large target) the MRS method, used with a coincident transmitter/receiver loop, can be an effective tool for locating a water-filled karst conduit. It was shown numerically that because an a priori orientation of the MRS profile with the karst conduit is used in the inversion scheme (perpendicular for instance), any error in this assumption introduces an additional error in locating the karst. However, the resulting error is within acceptable limits when the deviation is less than 30[deg]. The MRS results were compared with an electrical resistivity tomography (ERT) survey. It was found that in Poumeyssens, ERT is not able to locate the water-filled karst. On the other hand, ERT provides additional information about heterogeneities in the limestone

An assessment of the applicability of the heat pulse method toward the determination of infiltration rates in karst losing-stream reaches, 2007, Dogwiler T. , Wicks C. M. , And Jenzen E.
Quantifying the rate at which water infiltrates through sediment-choked losing stream reaches into underlying karstic systems is problematic, yet critically important. Using the one-dimensional heat pulse method, we determined the rate at which water infiltrated vertically downward through an estimated 600 m by 2 m sediment-choked losing-stream reach in the Devils Icebox Karst System of Central Missouri. The infiltration rate ranged from 4.9 3 1025 to 1.9 3 1026 m s21, and the calculated discharge through the reach ranged from 5.8 3 1022 to 2.3 3 1023 m3 s21. The heat pulse-derived discharges for the losing reach bracketed the median discharge measured at the outlet to the karst system. Our accuracy was in part affected by significant precipitation in the karst basin during the study period that contributed flow to the outlet from recharge areas other than the investigated losing reach. Additionally, the results could be improved by future studies that deal with identifying areas of infiltration in losing reaches and how that area varies in relation to changing flow conditions. However, the heat pulse method appears useful in providing reasonable estimates of the rate of infiltration and discharge of water through sediment-choked losing reaches.

Land cover mapping using Landsat satellite image classification in the Classical Karst - Kras region, 2007, Kokalj Ž, . , Oš, Tir K.

Such a diverse and sensitive eco-region as Karst needs to be managed with special attention and consideration of its natural and cultural resources. Land cover is an important indicator, which enables the analysis of their condition and development monitoring. Advanced satellite images classification represents an accurate and cost-effective alternative to the classical techniques of land cover mapping. The methods used to produce a reliable land cover map are presented in this paper. The complexity of the area requires a combination of various data such as Landsat satellite images, digital elevation model, digital orthophotos as well as existing topographic and thematic maps. The maximum likelihood algorithm was used as the main classifier and the accuracy of results was further improved by fuzzy classification, altitude and inclination filtering and auxiliary data integration.

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