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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 nivo-karst is a karst-like topography produced by the differential chemical weathering beneath snowbanks from snowmelt containing carbonic acid. it is found mostly in periglacial areas [1].?

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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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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PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS
Journal of Geochemical Exploration, 2000, Vol 68, Issue 3, p. 211-229
Organic geochemistry of paleokarst-hosted uranium deposits, South China
Abstract:
The paleokarst-hosted uranium deposits in organic-matter, clay-rich Devonian-Carboniferous carbonates are an economically important, new type of uranium deposit in China. The organic matter intimately associated with the uranium mineralization in this type of deposit has been characterized by petrographic, isotopic, gas chromatographic, pyrolysis-gas chromatographic, infrared spectroscopic and elemental geochemical methods. Comparing genetic types of the organic matter in unmineralized and mineralized samples indicates that no fundamental differences are found. The organic matter is chiefly of marine origin and contains a minor terrestrial component. The immature nature of the indigenous organic matter in the unmineralized samples shows generally a low-temperature history (less than or equal to max. 65 degrees C), and geologic data show a shallow maximal burial depth. By combining the organic geochemistry with the geological data, U-Pb dating and temperature determinations, an overall formation process for this type of uranium deposit is deduced. The formation of the paleokarst-hosted uranium deposits in South China is the result of: (1) repeated paleokarstifications of the Devonian and Carboniferous organic, clay-rich carbonate along the faults and unconformities between different strata because of the Hercynian and Yanshanian regional tectonism, and extensive formation of solution-collapse, solution-fault breccias; (2) accumulation of organic matter and clays in the paleocaverns and matrix of the breccias, fixation and adsorption of uranium by the organic matter and clays from the paleokarst waterflows that leached metals from the uranium-bearing host carbonates during their passage towards the karst zones, (3) reduction of uranium by the organic matter and formation of protore and low-grade ore; (4) circulation of heated formational waters and deep circulating, uraniferous meteoric waters by tectonic pumping, reworking the uranium-rich, paleocave-fillings, protore and low-grade ore, reduction and formation of primary uranium minerals (uraninite and coffinite) because of the reducing environment resulting from organic matter and sulfide. (C) 2000 Elsevier Science B.V. Ail rights reserved