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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 breathing hole is opening in the roof of a cave, cavern or other underground void through which air is sucked in and expelled in a rhythmic manner similar to inhalation and exhalation of breath [20]. related to blow hole and steam hole. synonyms: (french.) trou souffleur; (german.) luftloch, (greek.) anapneousa opi spileou; (spanish.) respirador; (turkish.) esintili delik.?

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Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
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Calculating flux to predict future cave radon concentrations, Rowberry, Matt; Marti, Xavi; Frontera, Carlos; Van De Wiel, Marco; Briestensky, Milos
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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 yucca mountain (Keyword) returned 3 results for the whole karstbase:
Cavity-based secondary mineralization in volcanic tuffs of Yucca Mountain, Nevada: a new type of the polymineral vadose speleothem, or a hydrothermal deposit?, 2005, Dublyansky Y. V. , Smirnov S. Z.
Secondary minerals (calcite, chalcedony, quartz, opal, fl uorite, heulandite, strontianite) residing in open cavities in the Miocene rhyolite tuffs of Yucca Mountain, Nevada have been interpreted by some researchers as "speleothemic" formations, deposited as a result of downward infiltration of meteoric waters (DOE, 2001, Whelan et al., 2002). The major mineral of the paragenesis, calcite, shows spectacular trend of the textural and crystal morphology change: from anhedral granular occurrences, through (optional) platelet, bladed and scepter varieties, to euhedral blocky morphologies. The trend is consistent with the overall decrease in the supersaturation of the mineral forming solution. Stable isotope properties of calcite evolve from 13C-enriched (?13C = +4 to +9 PDB) at early stages of growth to 13C-depleted (-5 to -10 ) at late stages. The non-cyclic character of the isotope record and extreme variations of isotopic values argue against the meteoric origin of mineral forming fluids. The ?13C >4 PDB require isotope partitioning between dissolved CO2 and CH4, which is only possible in reducing anoxic environment, but not in aerated vadose zone. Fluid inclusions studied in calcite, quartz and fluorite revealed that the minerals were deposited from thermal solutions. The temperatures were higher at early stages of mineral growth (60 to 85oC) and declined with time. Most late-stage calcites contain only all-liquid inclusions, suggesting temperatures less than ca. 35-50oC. Minerals collected close to the major fault show the highest temperatures. Gases trapped in fluid inclusions are dominated by CO2 and CH4; Raman spectrometry results suggest the presence of aromatic/cyclic hydrocarbon gases. The gas chemistry, thus, also indicates reduced (anoxic) character of the mineral forming fluids. Secondary minerals at Yucca Mountain have likely formed during the short-term invasion(s) of the deep-seated aqueous fluids into the vadose zone. Following the invasion, fluids, initially equilibrated with the deep (reduced, anoxic) environment, evolved toward equilibrium with the new environment (cooling, degassing, mixing with shallow oxidizing waters, etc.). While some features of mineralization are compatible with the "speleothemic" or "meteoric infiltration" model, most of the evidence does not lend itself to rational explanation within this model.

Evidence for a hypogene paleohydrogeological event at the prospective nuclear waste disposal site Yucca Mountain, Nevada, USA, revealed by the isotope composition of !uid-inclusion water, 2010, Dublyansky Yuri V. , Spö, Tl Christoph

Secondary calcite residing in open cavities in the unsaturated zone of Yucca Mountain has long been interpreted as the result of downward infiltration of meteoric water through open fractures. In order to obtain information on the isotopic composition (delta 18O) of the mineral-forming water we studied fluid inclusions from this calcite. Water was extracted from inclusions by heated crushing and the delta D values were measured using a continuous-low isotope-ratio mass spectrometry method. The delta 18O values were calculated from the delta 18O values of the host calcite assuming isotopic equilibrium at the temperature of formation determined by fuid-inclusion microthermometry. The delta D values measured in all samples range between −110 and −90‰, similar to Holocene meteoric water. Coupled delta 18O– delta D values plot significantly, 2 to 8‰, to the right of the meteoric water line. Among the various processes operating at the topographic surface and/or in the unsaturated zone only two processes, evaporation and water–rock exchange, could alter the isotope composition of percolatingwater. Our analysis indicates, however, that none of these processes could produce the observed large positive delta 18O-shifts. The latter require isotopic interaction between mineral-forming fluid and host rock at elevated temperature (N100 °C), which is only possible in the deepseated
hydrothermal environment. The stable isotope data are difficult to reconcile with a meteoric origin of the water from which the secondary minerals at Yucca Mountain precipitated; instead they point to the deep-seated provenance of the mineral-forming waters and their introduction into the unsaturated zone from below, i.e. a hypogene origin.


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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