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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 standing line is a rope of approximately 0.4375 inches or 11 mm in diameter that is tied to a solid anchor and is used for descending and ascending [13]. see also ascender; knot; mechanical ascender; prusik knot; prusiking.?

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;
See all featured articles from other geoscience journals

Mineralogical Magazine, 2001, Vol 65, Issue 1, p. 81-101
Mineralogy and geochemistry of trace elements in bauxites: the Devonian Schugorsk deposit, Russia
Abstract:
Processes of mineral alteration involving the mobilization and deposition of more than 30 chemical elements during bauxite formation and epigenesis have been studied on specimens from the Devonian Schugorsk bauxite deposit, Timan, Russia. Chemical analyses of the minerals were obtained by electron microprobe and element distribution in the minerals was studied by element mapping. Interpretation of these data also utilized high-resolution BSE and SE images. The main rock-forming minerals of the Vendian parent rock are calcite, dolomite, feldspar, aegirine, riebeckite, mica, chlorite and quartz; accessory minerals are pyrite, galena, apatite, ilmenite, monazite, xenotime, zircon, columbite, pyrochlore, chromite, bastnaesite and some others. Typically, the grain-size of the accessory minerals in both parent rock and bauxite is from 1 to 40 {micro}m. However, even within these rather small grains, the processes of crystal growth and alteration during weathering can be determined from the zonal distribution of the elements. The most widespread processes observed are: (1) Decomposition of Ti-bearing minerals such as ilmenite, aegirine and riebeckite with the formation of leucoxene', which is the main concentrator of Nb, Cr, V and W. Crystal growth can be traced from the zonal distribution of Nb (up to 16 wt.%). Vein-like leucoxene' is also observed in association with organics. (2) Weathering of columbite and pyrochlore: the source of Nb in leucoxene' is now strongly weathered columbite, while the alteration of pyrochlore is expressed in the growth of plumbopyrochlore rims around Ca-rich cores. (3) Dissolution of sulphide minerals and apatite and the formation of crandallite group minerals: crandallite' crystals of up to 40 {micro}m size show a very clear zonation. From the core to the rim of a crystal, the following sequence of elements is observed: Ca [->] Ba [->] Ce [->] Pb [->] Sr [->] Nd. Sulphur also shows a zoned but more complicated distribution, while the distribution of Fe is rather variable. A possible source of REE is bastnaesite from the parent rock. More than twelve crandallite type cells can be identified in a single crandallite' grain. (4) Alteration of stoichiometric zircon and xenotime with the formation of metamict solid solution of zircon and xenotime: altered zircon rims also bear large amounts of Sc (up to 3.5 wt.%), Fe, Ca and Al in the form of as yet unidentified inclusions of 1-2 {micro}m. Monazite seems to be the least altered mineral of the profile. In the parent rock, an unknown mineral of the composition (wt.%): ThO2 - 54.8; FeO - 14.6; Y2O5 -2.3; CaO - 2.0; REE - 1.8; SiO2 - 12.2; P2O5 - 2.8; total - 94.2 (average from ten analyses) was determined. In bauxite, another mineral was found, which has the composition (wt.%): ThO2 - 24.9; FeO - 20.5; Y2O5 - 6.7; CaO - 2.0; ZrO - 17.6; SiO2 - 8.8; P2O5 - 5.4; total - 89.3 (F was not analysed; average from nine analyses). Presumably, the second mineral is the result of weathering of the first one. Although the Th content is very high, the mineral is almost free of Pb. However, intergrowths of galena and pyrite are observed around the partially decomposed crystals of the mineral. Another generation of galena is enriched in chalcophile elements such as Cu, Cd, Bi etc., and is related to epigenetic alteration of the profile, as are secondary apatite and muscovite