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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. ...

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That rockfall is the falling of bedrock from a cliff or steep slope [16].?

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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 karst bauxites (Keyword) returned 8 results for the whole karstbase:
Relations between the location of the karst bauxites in the northern hemisphere, the global tectonics and the climatic variations during geological time, 1979, Nicolas Jean, Bildgen Pierre,
The study of the distribution of the laterites and bauxites of karst in the Northern Hemisphere shows that their location is not erratic. Most of the bauxites are ordered after their age, according to alignments indicating the existence of palaeoclimatic belts of humid intertropical type that were susceptible of having generated a laterizing pedogenesis, during geological time when these bauxites and laterites were formed. In relation to the present network of latitudes, these palaeoclimatic belts gradually took up more southerly positions, as geological time passed. A few of these formations appear, however, to be located outside the palaeclimatic belts within which they should occur. To explains this apparent anomaly, it is in consequence necessary to call into play on the one hand, the drift of the palaeoclimatic belts from the north to the south, and on the other, the mechanisms of ocean-floor spreading and of the movement of the continental plates. The results of these processes are integrated into the framework of the principles of global tectonics. They also correspond to those obtained from other disciplines, such as palaeomagnetism, palaeoclimatology, biogeography, palaeontology, etc.Extension of this study to the Southern Hemisphere can not be realized for the present, because the results of the researches relating to it in the field with which we are concerned are much too imprecise and the bibliography linked up with it too summary

Karst Bauxites. Bauxite Deposits on Carbonate Rocks, 1982, Brdossy G.

Distribution of the rare earth elements (REE, including La-Lu, Y) along vertical profiles is presented for four well-studied karst-bauxite deposits from Yugoslavia and Greece. For one deposit from Jamaica, La and Y contents are given. All deposits display a downward enrichment of the REE culminating at the base, where authigenic REE minerals have been formed. This REE pattern is characteristic for karst-bauxites formed in situ through the bauxitization of argillaceous material collected in karstic depressions. In this way, the highest enrichment of the REE in the sedimentary cycle has been achieved. Both light REE (LREE) and heavy REE (HREE) were 'mobile' during the bauxitization process and were concentrated at the alkaline barrier of the carbonate footwall. In four out of five studied deposits, the ratios SIGMA-LREE/SIGMA-HREE and La/Y in bauxites decrease downwards, showing an enrichment of the HREE relative to LREE. A further fractionation of the REE took place in the formation of authigenic REE minerals, which exhibit a very high enrichment of LREE relative to HREE. In spite of this, these minerals and bauxites in four studied deposits have a general similarity of the REE distribution patterns, which indicate a close genetic relationship

Origin of Eocene-covered karst bauxites of the Transdanubian Central Range (Hungary); evidence for early Eocene volcanism, 1992, Dunkl I,

During the middle Cretaceous the karst bauxites of NW Sardinia are controlled by a favourable climate, an aluminous mother rock (Berriasian marls) and a significant tectonic instability which allows a morphostructural paleosurface to be constituted on the intracontinental areas, away from the eustatic changes of sea level. In connection with the uplift rate, the aluminous material is distributed into three types of deposit. Their genetic depositional system and main features are incorporated in a geodynamic model applicable to prospecting

Paleoalpine karstification - The longest paleokarst period in the Western Carpathians (Slovakia), 1995, Cincura J, Kohler E,
The considerable areal extent and great thicknesses of Middle/Upper Triassic carbonate complexes influenced favourably the formation of karst during subaerial periods. The lower boundary of the Paleoalpine karst period is age-determined by the gradual emergence of the basement - during the Upper Cretaceous in the Central Western Carpathians and even earlier in the Inner Carpathians. The upper boundary can be dated by marine transgression The start of the transgression is not synchronous and it varies in a broad range from Upper Cretaceous to Upper Eocene and maybe even up to Oligocene/Miocene. The typical products of the period include typical karst bauxites filling karst cavities, ferri crusts, red clays, collapse and crackle breccias with speleothems, freshwater limestones or polymict conglomerates

Ce-anomalies in the textural components of upper Cretaceous karst bauxites from the Apulian carbonate platform (southern Italy), 1997, Mongelli G. ,
The chemical and mineralogical composition of Upper Cretaceous Apulian karat bauxites (southern Italy) and their textural components, i.e. ooids and matrix, has been studied. The bulk samples are composed of boehmite, hematite, anatase and kaolinite. The samples collected along a vertical profile show a downward enrichment for the elements Rb, Sr, Ba, Ni and Cr. A similar distribution is observed in deposits bauxitized in situ at the expense of matrix-like material collected in the karst zone. The ooids consist mainly of hematite with minor boehmite and anatase, whereas in the matrix boehmite prevails on hematite, kaolinite and anatase. In the void fillings in the matrix there is a Ca-fluorocarbonate having a Ce/Ce* of 5.8. The ooids, with the exception of Ce, are enriched in REE and show a higher (La/Yb)(ch) ratio relative to the matrix. The matrix exhibits a large positive Ce-anomaly whereas the ooids have negative Ce-anomaly. The Ce fractionation between the textural components can be explained assuming: (1) Ce oxidation and cerianite precipitation in the uppermost part of the deposits; (2) scavenging of REE from Ce-depleted percolating solutions by the iron oxide, inducing both REE-enrichment and Ce-negative anomalies in ooids; (3) remobilization of cerium as fluoride complex, as a consequence of more acidic conditions in the uppermost part of the deposit, and precipitation of Ce3 as fluorocarbonate mineral toward the carbonate bedrock barrier, at alkaline pH. Alternatively, the cerium remobilization, possibly as a carbonate-fluoride complex, could be due to an Eh decrease, favoured by a rise of the groundwater level. (C) 1997 Elsevier Science B.V

Growth of hematite and boehmite in concretions from ancient karst bauxite: clue for past climate, 2002, Mongelli G. ,
In the Peri-Adriatic Apulia Carbonate Platform (southern Italy), late Cretaceous karst bauxites mark an emergence period during a wet tropical climate. Bauxite formed through clay accumulation in the karst, 'in situ' bauxitization and late formation of iron-rich concretions in a water-unsaturated pedogenic environment. The concretions, which are geochemical recorders of the environment of formation, have a large core of Al-hematite surrounded by a cortex of alternating M-hematite and boehmite. Boehmite forms instead of Al-hematite at lower water activity values. Using a model of molecular diffusion and assuming the fluid flow negligible, the time necessary for growth of the concretions has been calculated. The average-sized core grew in similar to180 ka. The Al-hematite accretionary band grew in similar to180 ka whereas the boehmite accretionary band grew in similar to4.5 ka. The average bulk concretions possibly formed in 300-400 ka. The growth of the concretions is assumed to be a two-stage process. In the first stage, the core grew in a relatively long period of wet tropical climate. In the second stage, drier conditions favouring boehmite stability alternated to a wetter climate favouring Al-hematite stability. The growth of the bulk concretions is consistent with the Earth's long eccentricity cycle. (C) 2002 Elsevier Science B.V. All rights reserved

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