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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. ...

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. ...

Speleology in Kazakhstan

Shakalov on 11 Jul, 2012
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 glaciokarst is 1. a karst landscape that was glaciated during the cold periods of the pleistocene and displays major landforms of relict glacial origin. bare rock scars, locally with glacial striations, and limestone pavements are characteristic, due to the lack of rapid soil formation on the limestones since glacial stripping. dolines within a glaciokarst are mostly small and immature, as are caves, except where pre-glacial passages are intercepted. glaciokarst is almost synonymous with alpine karst, and some of the finest is developed on the high plateaus of the calcareous alps, south of salzburg, austria [9]. 2. a glaciated limestone region possessing both glacial and karst characteristics [10]. (french.) karst glaciaire; (german.) gebiet mit karst und glazial-formen; (greek.) pagheto-karst; (spanish.) glaciokarst; (turkish.) buzul karsti; (yugoslavian.) glaciokrs, glaciokras, glaciokarst. see also alpine karst; nival karst.?

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.
Engineering challenges in Karst, Stevanović, Zoran; Milanović, Petar
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Featured articles from other Geoscience Journals
Geochemical and mineralogical fingerprints to distinguish the exploited ferruginous mineralisations of Grotta della Monaca (Calabria, Italy), Dimuccio, L.A.; Rodrigues, N.; Larocca, F.; Pratas, J.; Amado, A.M.; Batista de Carvalho, L.A.
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
See all featured articles from other geoscience journals

Search in KarstBase

Your search for transvaal (Keyword) returned 11 results for the whole karstbase:
Some aspects of the Magnesium Problem in Karst Weathering with special reference to the North-east Transvaal, South Africa, 1973, Marker M. E.

Caves of the Strydpoort Mountains, Northeastern Transvaal, South Africa, 1974, Marker Margaret E.

The karst of Transvaal (South Africa)., 1976, Kavalieris I. , Martini Jacques E. J.
The Transvaal Karst is a world important example of a Karst developed on a very old dolomite. Its unique character is due to the composition of the rock and history of development. The dissolution of the dolomite is interesting and has an important effect on the character of the caves developed. The caves preserved in this area include the longest known in South Africa and are perhaps among the largest dolomite systems known in the world. They are very old and in some cases contain important palaeontological deposits (Australopithecine fauna). The caves to various degrees are in a state of de-generation, having been exposed for a very long period above the water-table. For the greater part of the Karst area, aggressive vadose waters, and long exposure has resulted in the accumulation of a thick covering of residual material. The plateau-like geomorphology and low rainfalls has prevented physical erosion and significant removal of this debris from the land surface. The caves themselves are often characterized by collapse and in general lack of formations. Massive calcite formation in the caves is usually partly or nearly completely redissolved and are relics of past colder climatic periods with winter rains. Formations active now are small, usually delicate and often due directly to evaporation. The heavy mantle of residual debris preserved under some of the more ancient of South African landsurface relics (the African Surface) poses a serious economic problem of stability, with mans' utilization of the environment. A greater understanding of the Karst, its evolution and properties is thus of considerable practical importance.

Alpha-radiation in Karst areas of the Transvaal, South Africa, 1981, Gamble Frances M.

Les cavits d'Afrique du Sud, 1985, Martini, J.
Caves of South Africa - A general description of the caves of South Africa is given. This includes a brief account of caving techniques and aspects of research on the geology, hydrology, morphology and mineralogy of the caves. Although caves systems are well developed in the country, a surface karst morphology is often non existent. Throughout emphasis is placed on the variable nature of the caves resulting from differences in lithology, e.g. complex hyperphreatic mazes in Proterozoic dolomite, shallow phreatic tubes in late Precambrian limestone, phreatic caves in soft Miocene lime-stone, and unusual vadose caves in quartzite and diabase.

Modern stromatolites in a karst structure from the Malmani Subgroup, Transvaal Sequence, South Africa, 1985, De Ncg,

THE EARLY PROTEROZOIC MISSISSIPPI VALLEY-TYPE PB-ZN-F DEPOSITS OF THE CAMPBELLRAND AND MALMANI SUBGROUPS, SOUTH-AFRICA - A REVIEW, 1995, 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

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

An overview of the geology of the Transvaal Supergroup dolomites (South Africa), 1998, Eriksson Pg, Altermann W,
In the Neoarchaean intracratonic basin of the Kaapvaal craton, between approximately 2640 Ma and 2516 Ma, two successive stromatolitic carbonate platforms developed. Deposition started with the Schmidtsdrif Subgroup, which is probably oldest in the southwestern part of the basin, and which contains stromatolitic carbonates, siliciclastic sediments and minor lava flows. Subsequently, the Nauga formation carbonates were deposited on peritidal flats located to the southwest and were drowned during a transgression of the Transvaal Supergroup epeiric sea, around 2550 Ma ago. This transgression led to the development of a carbonate platform in the areas of the preserved Transvaal and Griqualand West basins, which persisted for 30-50 Ma. During this time, shales were deposited over the Nauga Formation carbonates in the south-western portion of the epeiric sea. S subsequent period of basin subsidence led to drowning of the stromatolitic platform and to sedimentation of chemical, iron-rich silica precipitates of the banded iron formations (BIF) over the entire basin. Carbonate precipitation in the Archaean was largely due to chemical and lesser biogenic processes, with stromatolites and ocean water composition playing an important role. The stromatolitic carbonates in the preserved Griqualand West and Transvaal basins are subdivided into several formations, based on the depositional facies, reflected by stromatolite morphology, and on a intraformational unconformities; interbedded tuffs and available radiometric age data do not ye permit detailed correlation of units from the two basins. Thorough dolomitisation of most formations took place at different post-depositional stages, but mainly during early diagenesis. Partial silification was the result of diagenetic and weathering processes. Karstification of the carbonate rocks was related to periods of exposure to subaerial conditions and to percolation of groundwater. Such periods occurred locally at the time of carbonate and BIF deposition. Main karstification, however, probably took place during an erosional period between approximately 2430 Ma and 2320 Ma

Symposium Abstract: The relationship of palaeokarst to modern cave forming processes in the Transvaal, South Africe, 2001, Herries A. I. R.

Sedimentary manganese metallogenesis in response to the evolution of the Earth system, 2006, Roy Supriya,
The concentration of manganese in solution and its precipitation in inorganic systems are primarily redox-controlled, guided by several Earth processes most of which were tectonically induced. The Early Archean atmosphere-hydrosphere system was extremely O2-deficient. Thus, the very high mantle heat flux producing superplumes, severe outgassing and high-temperature hydrothermal activity introduced substantial Mn2 in anoxic oceans but prevented its precipitation. During the Late Archean, centered at ca. 2.75[no-break space]Ga, the introduction of Photosystem II and decrease of the oxygen sinks led to a limited buildup of surface O2-content locally, initiating modest deposition of manganese in shallow basin-margin oxygenated niches (e.g., deposits in India and Brazil). Rapid burial of organic matter, decline of reduced gases from a progressively oxygenated mantle and a net increase in photosynthetic oxygen marked the Archean-Proterozoic transition. Concurrently, a massive drawdown of atmospheric CO2 owing to increased weathering rates on the tectonically expanded freeboard of the assembled supercontinents caused Paleoproterozoic glaciations (2.45-2.22[no-break space]Ga). The spectacular sedimentary manganese deposits (at ca. 2.4[no-break space]Ga) of Transvaal Supergroup, South Africa, were formed by oxidation of hydrothermally derived Mn2 transferred from a stratified ocean to the continental shelf by transgression. Episodes of increased burial rate of organic matter during ca. 2.4 and 2.06[no-break space]Ga are correlatable to ocean stratification and further rise of oxygen in the atmosphere. Black shale-hosted Mn carbonate deposits in the Birimian sequence (ca. 2.3-2.0[no-break space]Ga), West Africa, its equivalents in South America and those in the Francevillian sequence (ca. 2.2-2.1[no-break space]Ga), Gabon are correlatable to this period. Tectonically forced doming-up, attenuation and substantial increase in freeboard areas prompted increased silicate weathering and atmospheric CO2 drawdown causing glaciation on the Neoproterozoic Rodinia supercontinent. Tectonic rifting and mantle outgassing led to deglaciation. Dissolved Mn2 and Fe2 concentrated earlier in highly saline stagnant seawater below the ice cover were exported to shallow shelves by transgression during deglaciation. During the Sturtian glacial-interglacial event (ca. 750-700[no-break space]Ma), interstratified Mn oxide and BIF deposits of Damara sequence, Namibia, was formed. The Varangian ([identical to] Marinoan; ca. 600[no-break space]Ma) cryogenic event produced Mn oxide and BIF deposits at Urucum, Jacadigo Group, Brazil. The Datangpo interglacial sequence, South China (Liantuo-Nantuo [identical to] Varangian event) contains black shale-hosted Mn carbonate deposits. The Early Paleozoic witnessed several glacioeustatic sea level changes producing small Mn carbonate deposits of Tiantaishan (Early Cambrian) and Taojiang (Mid-Ordovician) in black shale sequences, China, and the major Mn oxide-carbonate deposits of Karadzhal-type, Central Kazakhstan (Late Devonian). The Mesozoic period of intense plate movements and volcanism produced greenhouse climate and stratified oceans. During the Early Jurassic OAE, organic-rich sediments host many Mn carbonate deposits in Europe (e.g., Urkut, Hungary) in black shale sequences. The Late Jurassic giant Mn Carbonate deposit at Molango, Mexico, was also genetically related to sea level change. Mn carbonates were always derived from Mn oxyhydroxides during early diagenesis. Large Mn oxide deposits of Cretaceous age at Groote Eylandt, Australia and Imini-Tasdremt, Morocco, were also formed during transgression-regression in greenhouse climate. The Early Oligocene giant Mn oxide-carbonate deposit of Chiatura (Georgia) and Nikopol (Ukraine) were developed in a similar situation. Thereafter, manganese sedimentation was entirely shifted to the deep seafloor and since ca. 15[no-break space]Ma B.P. was climatically controlled (glaciation-deglaciation) assisted by oxygenated polar bottom currents (AABW, NADW). The changes in climate and the sea level were mainly tectonically forced

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