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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 shield; cave shield is 1. a thin circular disc of calcite projecting from a cave wall at any upward inclination, commonly a meter or more in diameter and with the underside draped with stalactites and curtains. the shield is actually a double disc with a thin central crack that acts as the continuation of a wallrock fracture. it grows by water moving up the crack under pressure and depositing calcite on both sides of its outer rim. shields are rare, but lehman cave, nevada, has more than a hundred of them [9]. 2. a disk-shaped speleothem standing edgewise at a high angle [10]. 3. a geologically stable and undisturbed continental block [16].?

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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
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Search in KarstBase

Your search for archaean (Keyword) returned 9 results for the whole karstbase:
Tunnel Caves in Swedish Archaean Rocks, 1981, Sjoberg R.

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

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

Fault and stratigraphic controls on volcanogenic massive sulphide deposits in the Strelley Belt, Pilbara Craton, Western Australia, 1998, Vearncombe S. , Vearncombe J. R. , Barley M. E. ,
Early Archaean, Fe-Zn-Cu volcanogenic massive sulphide deposits of the Strelley Belt, Pilbara Craton. occur at the top of a volcanic dominated sequence, at the interface of felsic volcanic rucks and siliceous laminites, beneath an unconformity overlain by elastic sedimentary rocks. The structure of the Sulphur Springs and Kangaroo Caves VMS deposits is relatively simple, with the present morphology reflecting original deposition rather than significant structural modification. The rocks have been tilted giving an oblique cross-sectional view of discordant high-angle, deep penetrating faults in the footwall, which splay close to the zones of voltcanogenic massive sulphide mineralization. Faults do not extend far into the overlying sedimentary cover, indicating their syn-volcanic and syn-mineralization timing. Both the Sulphur Springs and Kangaroo Caves sulphide deposits are located within elevated grabens in a setting similar to massive sulphide mineralization in modern back-are environments. Mineralization at Sulphur Springs and Kangaroo Caves is located at the edge of the grabens, at the site of intersecting syn-volcanic extensional faults.

Late Archaean foreland basin deposits, Belingwe greenstone belt, Zimbabwe, 2001, Hofmann A. , Dirks P. H. G. M. , Jelsma H. A. ,
The c. 2.65 Ga old sedimentary Cheshire Formation of the Belingwe greenstone belt (BDB), central Zimbabwe, has been studied in detail for the first time to shed some light on the much debated evolution of this classical belt. The Cheshire Formation rests sharply on a mafic volcanic unit (Zeederbergs Formation) and comprises a basal, eastward-sloping carbonate ramp sequence built of shallowing-upward, metre-scale sedimentary cycles. The cycles strongly resemble Proterozoic and Phanerozoic carbonate cycles and might have formed by small-scale eustatic sea level changes. The top of the carbonate ramp is represented by a karst surface. The carbonates are overlain by and grade laterally to the east into deeper water (sub-wave base) siliciclastic facies. Conglomerate, shale and minor sandstone were deposited by high- to low-density turbidity currents and were derived from the erosion of Zeederbergs-like volcanic rocks from the east. Shortly after deposition, the Cheshire Formation and underlying volcanics were affected by a northwest-directed thrusting event. Thrusting gave rise to the deformation of semi-consolidated sediments and resulted in the juxtaposition of a thrust slice of Zeederbergs basalts onto Cheshire sediments. The stratigraphy, asymmetric facies and sediment thickness distribution, palaeogeographic constraints and evidence for an early horizontal tectonic event suggest that the Cheshire Formation formed in a foreland-type sedimentary basin. (C) 2001 Elsevier Science B.V. All rights reserved

Palaeo-coastal morphology of the neoproterozoic Badami basin - Some field evidences from Khanapur, Bagalkot district, Karnataka, 2002, Dey S, Rao Rg, Kumar S, Veerabhaskar D,
The Neoproterozoic Badami Group of the Kaladgi-Badami basin consists of an undisturbed sequence of sandstone, shale and limestone exposed in the northern districts of Karnataka and adjoining parts of Maharashtra (Viswanathiah, 1977; Jayaprakash et al. 1987). The sequence unconformably overlies Archaean granitoids, schists and the Mesoproterozoic Bagalkot Group of sediments. The environment of deposition of the Badami Group has been interpreted as shallow marine (Sathyanarayan, 1994). This note presents some field evidences around Khanapur village, Bagalkot district revealing the nature of palaeo-coastal morphology during the deposition of Cave Temple arenite (CTa), the main sandstone member of the Badami Group

Contribution to the speleology of Sterkfontein cave, Gauteng province, South Africa., 2003, Keyser Andre, Martini Jacques E. J. , Moen Henri F. G. , Wipplinger Paul E.
The authors present more data about the speleological aspect of the Sterkfontein Cave, famous for its bone breccia which yielded abundant hominid remains. They also briefly review the previous voluminous studies by numerous authors, which are mainly dealing with the paleontology, stratigraphy and sedimentology of the breccia. The present investigations were oriented to hitherto poorly investigated aspects such as detail mapping of the cave, its country rock stratigraphy and recording the underground extension of the basal part of the breccia body. The cave consists of a complex network of phreatic channels, developed along joints in Neoarchaean cherty dolostone over a restricted surface of 250x250m. The combined length of all passages within this area amounts to 5,23km. The system extends over a height of about 50m and the dry part of it is limited downwards by the water-table appearing as numerous static pools. The fossiliferous breccia (= Sterkfontein Formation) forms an irregular lenticular mass 75x25m horizontally by 40m vertically, which is included within the passage network. It crops out at surface and in the cave, and resulted from the filling of a collapse chamber, which was de-roofed by erosion. The present investigation confirmed that the cave and the Sterkfontein Formation are part of a single speleogenetic event. The breccia resulted from cavity filling by sediments introduced from a pit entrance, whereas many of the phreatic passages around it, which are developed at the same elevation, were only partly filled or remained entirely open up to present. This filling took place mainly in a vadose environment. Taking into account the age of the Sterkfontein Formation (>3,3-1,5 My, from base to top), the geomorphic evolution of the landscape and the context of other caves in the region, it seems that the cave might have started to form 5 My ago. It has been continuously developing up to present as a result of a slow drop of the water-table.

Contribution to the speleology of Sterkfontein Cave, Gauteng Province, South Africa, 2004, Martini J. E. J. , Wipplinger P. E. , Moen H. F. G. , Keyser A.

The authors present more data about the speleological aspect of the Sterkfontein Cave, famous for its bone breccia which yielded abundant hominid remains. They also briefly review the previous voluminous studies by numerous authors, which are mainly dealing with the paleontology, stratigraphy and sedimentology of the breccia. The present investigations were oriented to hitherto poorly investigated aspects such as detail mapping of the cave, its country rock stratigraphy and recording the underground extension of the basal part of the breccia body. The cave consists of a complex network of phreatic channels, developed along joints in Neoarchaean cherty dolostone over a restricted surface of 250x250m. The combined length of all passages within this area amounts to 5,23km. The system extends over a height of about 50m and the dry part of it is limited downwards by the water-table appearing as numerous static pools. The fossiliferous breccia (= Sterkfontein Formation) forms an irregular lenticular mass 75x25m horizontally by 40m vertically, which is included within the passage network. It crops out at surface and in the cave, and resulted from the filling of a collapse chamber, which was de-roofed by erosion.
The present investigation confirmed that the cave and the Sterkfontein Formation are part of a single speleogenetic event. The breccia resulted from cavity filling by sediments introduced from a pit entrance, whereas many of the phreatic passages around it, which are developed at the same elevation, were only partly filled or remained entirely open up to present. This filling took place mainly in a vadose environment.
Taking into account the age of the Sterkfontein Formation (>3,3-1,5 My, from base to top), the geomorphic evolution of the landscape and the context of other caves in the region, it seems that the cave might have started to form 5 My ago. It has been continuously developing up to present as a result of a slow drop of the water-table.


STYLES OF HYPOGENE CAVE DEVELOPMENT IN ANCIENT CARBONATE AREAS OVERLYING NON-PERMEABLE ROCKS IN BRAZIL AND THE INFLUENCE OF COMPETING MECHANISMS AND LATER MODIFYING PROCESSES, 2009, Augusto S. Auler

A significant proportion of the karst areas in Brazil develop over ancient cratonic or tectonically stable zones overlying Precambrian quartzites or Archaean crystalline basement (granite, gneiss, schist). In such settings, due to the low transmissivity and highly anisotropic nature of the bedrock, major groundwater flow of regional scale tends to be restricted, and diffuse ascending cross-formational flow into the carbonate is limited to a few favourable input zones. Nevertheless, caves displaying hypogene features occur in several areas, although few contain the full suite of speleogenetic forms commonly found in “classic” better studied areas of Europe and North America. Major known hypogene caves in Brazil tend to be located in zones bordering the more stable cratonic areas, such as in Vazante and Toca da Boa Vista karst areas, where fault zones are likely candidates for providing ascending flow paths towards the carbonate. The absence of transmissive beds above the carbonate limits the existence of outflow routes. Brazilian hypogene caves develop in mostly horizontally bedded or gently dipping bedrock and typically do not display the three-dimensional character of many hypogene caves elsewhere. The speleogenetic role of competing mechanisms such as sulphuric acid dissolution due to pyrite oxidation and condensation corrosion tend to overprint original forms as well as produce similar convergent features.


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