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Enviroscan Ukrainian Institute of Speleology and Karstology


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Community news

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 pisolite, pisolith is see cave pearl.?

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 africa (Keyword) returned 143 results for the whole karstbase:
Showing 46 to 60 of 143
THE EARLY PROTEROZOIC MISSISSIPPI VALLEY-TYPE PB-ZN-F DEPOSITS OF THE CAMPBELLRAND AND MALMANI SUBGROUPS, SOUTH-AFRICA - A REVIEW, 1995,
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Martini J. E. J. , Eriksson P. G. , Snyman C. P. ,
Pb-Zn-F deposits occur in the very late Archaean (2.55 Ga) shallow marine dolostone of the relatively undeformed Campbellrand and Malmani Sub-groups, which are overlain unconformably by the lower Proterozoic Postmasburg and Pretoria Group siliciclastics. They consist of stratiform deposits formed by replacement and porosity-filling, as well as pipes, ring-shaped and irregular bodies associated with collapse breccia. In the Transvaal basin the latter were generated during the karst denudation period between the deposition of the Chuniespoort Group (ending at similar to 2.4 Ga) and of the Pretoria Group (starting at 2.35 Ga). A part of these mineralisations were overprinted by the metamorphism of the Bushveld Complex intrusion at 2.06 Ga. In the Transvaal basin, the age of the mineralisation is constrained between the start of the Pretoria Group deposition and the Bushveld intrusion. It is concluded that, although most of the mineralisations are characteristic of the Mississippi Valley-type, some of the northernmost occurrences, rich in siderite, are less typical. A classic genetic model is proposed. In an environment characterised by tensional tectonics and basin development, brines of basinal origin were heated by circulation into pre-Chuniespoort rocks, leached metals from the rocks they permeated, and rose as hydrothermal plumes. At relatively shallow depth they deposited minerals after mixing with water of surficial origin

Geology and ore genesis of the manganese ore deposits of the Postmasburg manganese-field, South Africa, 1995,
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Plehweleisen E. , Klemm D. D. ,

GEOLOGY AND ORE GENESIS OF THE MANGANESE ORE-DEPOSITS OF THE POSTMASBURG MANGANESE-FIELD, SOUTH-AFRICA, 1995,
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Vonplehweleisen E. , Klemm D. D. ,
The Postmasburg Mn/Fe-ores occur exclusively in dolomitic Precambrian sinkhole structures with siliceous breccias and shales as hostrocks. The main manganese minerals are braunite and bixbyite, apart from secondary alteration products of the psilomelane-manganomelane family. Various generations of ore minerals could be identified. The ore mineralization is subdivided into three different genetic types. They are classified either as pure karst deposits or as combined formations of karst origin and shallow marine sedimentation due to the transgression of the Banded Iron Formation (BIF) sea. Post-sedimentary metamorphism is identified as very low grade. The development of the different ore types is illustrated schematically

Carbon Dioxide variations in Cango Cave, South Africa, 1996,
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Craven S. A.

Karst-hosted fresh-water Paleoproterozoic manganese deposits, Postmasburg, South Africa, 1996,
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Gutzmer Jens, Beukes Nicolas J. ,

Morphological affinities of the proximal ulna from Klasies River main site: Archaic or modern?, 1996,
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Churchill Se, Pearson Om, Grine Fe, Trinkaus E, Holliday Tw,
The Middle Stone Age (MSA) asociated hominids from Klasies River Mouth (KRM) have taken on a key role in debate about the origins of modern humans, with their craniofacial remains seen as either representing the earliest well-dated modern humans in southern Africa or orthognathic late archaic humans. Diagnostic postcranial remains from Klasies are few, but one specimen-a proximal right ulna from the lower SAS member-is useful For assessing the morphological affinities of these hominids. Canonical variates analysis using 14 proximal ulnar dimensions and comparative data from European, west Asian and African archaic humans, and Levantine Mousterian, European Upper Paleolithic, African Epipaleolithic and diverse recent modern human samples (many of recent African descent) were employed to assess the morphological affinities of this specimen. Results suggest an archaic total morphological pattern for the Klasies ulna. Analysis of diaphyseal cross-sectional geometry reveals an ulnar shaft with relatively thick cortical bone, but the specimen cannot be readily distinguished from Neandertals or early anatomically modem humans on the basis of shaft cross-sectional properties. If the isolated ulna from Klasies is indicative of the general postcranial morphology of these hominids, then the MSA-associated humans from KRM may not be as modern as has been claimed from the craniofacial material. It ii: possible also that the skeletal material from KRM reflects mosaic evolution-retention of archaic postcranial characteristics. perhaps indicating retention of archaic habitual behavior patterns, in hominids that were becoming craniofacially modern. (C) 1996 Academic Press Limited

Morphology of the border cave hominid ulna and humerus, 1996,
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Pearson O. M. , Grine F. E. ,
Hominid bones from Border Cave (BC) have been the subject of controversy with regard to the question of modern human origins. New dating assays suggest that while some of the BC remains are of comparatively recent age (i.e. < 20 kyr), several postcranial fragments derive from the Middle Stone Age (MSA) layers. Among the latter, a proximal ulna in comparable to one from the MSA at Klasies River Mouth, in that both have an archaic pattern of morphology in the relative height of the coronoid and olecranon processes. This configuration appears to characterize Neandertals, and is displayed also by more ancient African ulnae. The BC humeral diaphysis has moderately thick cortical bone, but us otherwise unremarkable. The proximal ulnar morphology might suggest that the MSA inhabitants of South Africa engaged in activities similar to those of Neandertals and other postcranially archaic hominids. If the modern-looking BC-1 cranium in contemporaneous with the BC postcranial bones, this would bear testament to the mosaic nature of human evolution. Alternatively, if BC-1 proves to be of recent derivation, and the postcrania are as old as the base of the BC MSA sequence has been claimed to be (c. 195 kyr), they might have been associated with more archaic crania (perhaps similar to Florisbad). Final resolution of these questions awaits determination of the absolute ages of the BC-1 cranium and the BC postcranial bones

The geomorphology of solution cave sequences in the Kalk Bay Mountains, southern Cape Peninsula. BSc thesis, 1996,
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Shearer, H.

The Kalk Bay Mountains of the southern Cape Peninsula, South Africa, show marked development of pseudokarstic features such as caverns, dolines and grikes. These features have formed over at least 100 million years on supposed inert quartzitic sandstones of the Peninsula Formation of the Table Mountain Group. Pseudokarst on sandstone is relatively rare world-wide and various aspects of cave genesis are highlighted in the Cape Peninsula. Cape Peninsula pseudokarst is relict, occurs at high altitudes above the present water table and could provide clues to palaeoenvironmental conditions during the African erosion period.
The cave systems in the Kalk Bay Mountains occur in at least three levels in the thickly-bedded sandstone. These different levels are the result of differential uplift during the Miocene and Pliocene. The Cape Peninsula Mountains are tabular and blocky, as opposed to the fold mountains of the rest of the South Western Cape. Much more of the overlying sedimentary layers in the Cape Peninsula have also been removed by weathering and erosive processes. The caves can be compared to similar pseudokarst features on sandstone in areas such as Gran Sabana, Venezuela. The acidic water chemistry in Venezuela contributes to a very intensive weathering environment. Present day humid tropical conditions in Venezuela are likely to be similar to palaeoclimatic conditions in the Kalk Bay Mountains, contributing to sandstone cave genesis.


Carbon Dioxide variations in Cango Cave, South Africa [Corrigendum], 1997,
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Craven S. A.

Phnomnes karstiques et pseudo-karstiques dans des quartzites au Burundi, 1997,
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Peyrot, Bernard
Central Africa, underground karstic caves are to be found in precambrian carbonated series, but also in quartzite as in the case of Burundi. The arenisation process which took place during very wet periods of intense biological activity may explain the origin of these caves and of karstic landforms such as pavements and pinnacles.

Geographic variation and genetic relationships in populations of the Androniscus dentiger complex from Central Italy (Isopoda, Oniscidea, Trichoniscidae), 1997,
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Allegrucci Giuliana, Gentile Gabriele
Androniscus dentiger is a terrestrial isopod distributed from Great Britain to North Africa, inhabiting humid edafic environments, superficial underground compartments and both natural and artificial caves. In this study allozyme data have been used to investigate the geographic variation and the genetic relationships of several populations of A. dentiger from Central Italy, using as outgroups populations from four congeneric species, A. calcivagus, A. cfr. subterraneus, A. spelaeorum, and A. degener. Multivariate analysis of A. dentiger allele frequencies indicates the existence of a group of populations (group A) distributed in a wide geographic area which are genetically slightly differentiated, and several populations (arbitrarily defined as group B) which show differentiation levels comparable to those observed between the morphologically well differentiated species. The low valley of the river Tiber seems to act as an effective geographic barrier between the populations from group A and the remaining ones. The genetic divergence between populations within the group A seems to have a recent origin. This is suggested by the low genetic distances and heterozygosity values within the group A, and by the very low number of private alleles occurring in this group. The high degree of intraspecific and interspecific genetic differentiation is not consistent with the levels of morphological differentiation traditionally used to distinguish different species within this genus. On the whole, these data suggest that A. dentiger might be considered as a complex of cryptic/sibling species.

The effect of metal cations on the kinetics of limestone neutralisation of acid waters, 1997,
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Vantonder G. J. , Schutte C. F. ,
Limestone (CaCO3), is a lower cost alternative to lime (CaO) for the neutralisation of acid water, but the limestone neutralisation reaction is impaired by iron(II), iron(III) and aluminium in solution. This paper describes the kinetics of limestone neutralisation in the presence of these metals. The reaction rate is affected by the type of metal cation, by the concentration of the cation and by pH. At pH levels below 2.0 the limestone dissolution reaction rate decreases sharply with increasing pH. In the pH range 4.0 to 5.5 the reaction rate decreases linearly with increasing pH. The pH range 2.0 to 4.0 is a transition range, from the non-linear to linear dissolution rate characteristics. Metal concentrations below 80 mg l(-1): At pH levels less than 4, iron(II) had the strongest suppressing effect followed by aluminium, while the presence of iron(III) increased the reaction rate. In the pH range 4.0 to 5.5 aluminium had the strongest suppressing effect followed by iron(III) and iron(II). Metal concentrations above 80 mg l(-1): Iron(II) and aluminium suppress the reaction rate at all pH levels. At pH levels less than 4 iron(II) had the strongest suppressing effect, followed by aluminium. In the pH range 4.0 to 5.5 aluminium had the strongest suppressing effect followed by iron(II). With iron(III) the rate is suppressed at pH levels below 2, however the rate is speeded up in the pH range 25 to 3.5. At higher pH levels, the iron(III) concentration is limited to less than 80 mg l(-1) because of precipitation of iron(III) at pH levels higher than 2.5. The extent to which the overall neutralisation reaction proceeds was modelled to assist in reactor design. The overall reaction is impaired most by aluminium, followed by iron(II) and iron(III)

Symposium Abstract: Speleology and Sedimentation at Makapansgat, Northern Transvaal, South Africa, 1998,
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Herries A. J. R. , Latham A. G.

The speleological potential of limestone karst in Zambia (Central Africa) - A reconnaissance survey, 1998,
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Kaiser T. M. , Seiffert C. , Truluck T.

Thesis Abstract: The geomorphology of solution cave sequences in the Kalk Bay mountains, southern Cape Peninsular [South Africa], 1998,
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Shearer H.

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