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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 solution notch is these form wherever humic soil borders on a very steep or vertical limestone surface. the rock becomes undercut by water rich in biogenic co2. in the cone karst of the humid tropics, foot caves occur which are over-sized enlargements of solution notches [3].?

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.
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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 performance (Keyword) returned 22 results for the whole karstbase:
Showing 16 to 22 of 22
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.

The Seulo Caves Project, Sardinia: a report on archaeological work undertaken in 2009 and 2010, 2011, Skeates, R.

This report introduces a new archaeological research project investigating the human uses of caves in the territory of Seulo, central Sardinia, and presents the preliminary results of archaeological field-survey, cave-survey, and excavation work undertaken in 2009 and 2010. At least nine caves were occupied in this area during prehistory, between the Middle Neolithic and the Bronze Age (c.4700-850 cal BC). All appear to have been used for the performance of rituals, and can be compared to the ritual use of caves identified elsewhere in the Central Mediterranean region. Nevertheless, significant differences can also be identified at each cave, adding detail and diversity to our understanding of the human uses of caves.


Effects of dynamically variable saturation and matrix-conduit coupling of flow in karst aquifers, 2011, Reimann T. , Geyer T. , Shoemaker W. B. , Liedl R. , Sauter M.

Well-developed karst aquifers consist of highly conductive conduits and a relatively  low permeability fractured and/or porous rock matrix and therefore behave as a dualhydraulic  system. Groundwater flow within highly permeable strata is rapid and transient  and depends on local flow conditions, i.e., pressurized or nonpressurized flow. The  characterization of karst aquifers is a necessary and challenging task because information  about hydraulic and spatial conduit properties is poorly defined or unknown. To investigate  karst aquifers, hydraulic stresses such as large recharge events can be simulated with hybrid  (coupled discrete continuum) models. Since existing hybrid models are simplifications of  the system dynamics, a new karst model (ModBraC) is presented that accounts for unsteady  and nonuniform discrete flow in variably saturated conduits employing the Saint-Venant  equations. Model performance tests indicate that ModBraC is able to simulate (1) unsteady  and nonuniform flow in variably filled conduits, (2) draining and refilling of conduits with  stable transition between free-surface and pressurized flow and correct storage  representation, (3) water exchange between matrix and variably filled conduits, and (4)  discharge routing through branched and intermeshed conduit networks. Subsequently,  ModBraC is applied to an idealized catchment to investigate the significance of free-surface  flow representation. A parameter study is conducted with two different initial conditions:  (1) pressurized flow and (2) free-surface flow. If free-surface flow prevails, the systems is  characterized by (1) a time lag for signal transmission, (2) a typical spring discharge pattern  representing the transition from pressurized to free-surface flow, and (3) a reduced conduitmatrix  interaction during free-surface flow.


Assessing copepod (Crustacea: Copepoda) species richness at different spatial scales in northwestern Romanian caves, 2011, Ioana N. Meleg, Frank Fiers, Oana Moldovan

The aim of the present study was to assess copepod species richness in groundwater habitats from the Pădurea Craiului Mountains, Transylvania (northwestern Romania). Five species richness estimators (one asymptotic, based on species accumulation curves, and four non-parametric) were compared by testing their performances in estimating copepod species richness at three hierarchical spatial scales: cave, hydrographic basin, and karstic massif. Both epigean and hypogean species were taken in account. Two data sets were used in computing copepod species richness: 1. samples collected continuously during one year (dripping water) and seven months (pools) from five caves, and 2. samples collected from pools in twelve additional caves (data gathered from literature). Differences in copepod species richness among caves and hydrographic basins suggest that local environmental features are important in determining local species richness trends.


Swimming performance of epigeal and hypogeal species of Characidae, with an emphasis on the troglobiotic Stygichthys typhlops Brittan & Bhlke, 1965, 2012, Costa Sampaio F. A. , Santos Pompeu P. , De Andrade E Santos H. , Lopes Ferreira R.

Swimming performance of fish constitutes a good ecophysiological tool to evaluate the ability of species to use different types of habitats. In order to understand how the swimming performance is related to the hydraulic environment, we compared the critical velocity of five fish (Characidae): Stygichthys typhlops (groundwater troglobiotic); Piabina argentea and Bryconamericus stramineus (riverine); Hemigrammus marginatus (generalist, found in rivers and floodplains) and Psellogrammus kennedyi (lacustrine). Swimming speed tests were performed in a respirometer-type apparatus. Total body length was the variable that best explained the maximum speed attained by all species under study. The critical swimming speed values (in body lengths per second) for each species were as follows: P. argentea (13.75); B. stramineus (9.32); H. marginatus (6.32); P. kennedyi (4.00); and lower in hypogean species, S. typhlops (3.31). All data of this study suggest a strong correlation between swimming performance and the hydraulic environment in which the species are found. The riverine, generalist and lacustrine species (the troglobiotic being included in the last group) showed a trend toward a decrease in speed.

 


An electrical resistivity imaging-based strategy to enable site-scale planning over covered palaeokarst features in the Tournaisis area (Belgium), 2012, Kaufmann O. , Deceuster J. , Quinif Y.

Since the beginning of the 20th century, more than 150 sinkhole occurrences, mainly dropout (or covercollapse)sinkholes, have been reported in the Tournaisis area (south-eastern Belgium). Land-use planning in such a context has to take into account hazards linked with sinkhole subsidence and collapse. Management maps, drawn at a regional scale, point out zones where karstic risks have to be taken into account when dealing with infrastructure or building projects. However, karst hazard is highly variable in three dimensions at the local scale. Therefore, for such purposes, an accurate methodology is needed to detect and delineate covered karst features, especially when located in urbanized areas. As geophysical investigations are sensitive to contrasts in physical properties of soils, these methods can be useful to detect such targets. The specific karstic context encountered in the Tournaisis area strongly guides the choice of investigation techniques. Electrical resistivity imaging (ERI) methods were tested on a wellknown site where dropout sinkholes occurred formerly. This site was also studied using static cone penetration tests (CPT) and boreholes. A 3D inverted resistivity model was computed based on the 2D ERI models obtained after inversion. Resistivity profiles were extracted at each CPT location and compared to geotechnical results to determine an empirical and site-specific resistivity law that allows discrimination between weathered zones and sound limestone. Performance tests were conducted to evaluate the potential of the proposed methodology for two typical engineering problems based on two current hypotheses. Borehole data were used as ground truth. Similar performance tests were also computed using the CPT depth to bedrock model. The results of these performance tests are compared and discussed. Finally, an ERI-based investigation strategy is proposed to assess karst hazard in palaeokarstic context, such as encountered in the Tournaisis area, at the scale needed for building and infrastructure purposes. 


Evaluation of the US DOE’s conceptual model of hydrothermal activity at Yucca Mountain, Nevada, 2014,

A unique conceptual model describing the conductive heating of rocks in the thick unsaturated zone of Yucca Mountain, Nevada by a silicic pluton emplaced several kilometers away is accepted by the US Department of Energy (DOE) as an explanation of the elevated depositional temperatures measured in fluid inclusions in secondary fluorite and calcite. Acceptance of this model allowed the DOE to keep from considering hydrothermal activity in the performance assessment of the proposed high-level nuclear waste disposal facility. The evaluation presented in this paper shows that no computational modeling results have yet produced a satisfactory match with the empirical benchmark data, specifically with age and fluid inclusion data that indicate high temperatures (up to ca. 80 _C) in the unsaturated zone of Yucca Mountain. Auxiliary sub-models complementing the DOE model, as well as observations at a natural analog site, have also been evaluated. Summarily, the model cannot be considered as validated. Due to the lack of validation, the reliance on this model must be discontinued and the appropriateness of decisions which rely on this model must be re-evaluated.A unique conceptual model describing the conductive heating of rocks in the thick unsaturated zone of Yucca Mountain, Nevada by a silicic pluton emplaced several kilometers away is accepted by the US Department of Energy (DOE) as an explanation of the elevated depositional temperatures measured in fluid inclusions in secondary fluorite and calcite. Acceptance of this model allowed the DOE to keep from considering hydrothermal activity in the performance assessment of the proposed high-level nuclear waste disposal facility. The evaluation presented in this paper shows that no computational modeling results have yet produced a satisfactory match with the empirical benchmark data, specifically with age and fluid inclusion data that indicate high temperatures (up to ca. 80 _C) in the unsaturated zone of Yucca Mountain. Auxiliary sub-models complementing the DOE model, as well as observations at a natural analog site, have also been evaluated. Summarily, the model cannot be considered as validated. Due to the lack of validation, the reliance on this model must be discontinued and the appropriateness of decisions which rely on this model must be re-evaluated.


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