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Enviroscan Ukrainian Institute of Speleology and Karstology

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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 meander belt is a zone within which meandering of a stream occurs [16].?

Checkout all 2699 terms in the KarstBase Glossary of Karst and Cave Terms

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What is Karstbase?



Browse Speleogenesis Issues:

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;
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Your search for calcification (Keyword) returned 7 results for the whole karstbase:
Carte hydrogomorphologique, hydrogologie et hydrochimie du karst de Dorvan (Ain), 1983,
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Gibert J. , Laurent R. , Maire R.
PRESENTATION OF THE HYDROGEOMORPHOLOGICAL MAP AT 1/100,000 ON KARST OF DORVAN (SOUTHERN JURA, AIN, FRANCE. Main researches about hydrology and hydrochemistry on this karst - The Dorvan massif is a low mountain Jurassian karst with a wet temperate climate and a little nival influence. The surface relief is covered with important decalcification clay. The drainage of the karst is assumed by superimposed systems, according to the excavation of the Torcieu watergap. The flow of the main outlet (Pissoir) is a pluvial type, which presents an annual cycle with a maximum in winter and a minimum in summer. The specific discharge is 31.4 l/s/km2. The dissolution rate is high: 81 mm/ky. 50% of the corrosion interests the epikarst, 50% interests the endokarst. During the Pleistocene, the glaciations played a direct or indirect role on the evolution of the Dorvan karst: nivo-karst during the Wrm; fluvio-glacial up-building of the Torcieu watergap and correlated water logging of the lower karst during Wrm and Tardiglacial periods; probable direct action of glaciers during the Riss.

Impact des proprits hydrodynamiques du substrat karstique sur la nature du sol en milieu mditerranen, 1989,
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Verheye, W. H.
The impact of the hydrodynamic properties of the karst substratum over the soil characteristic in mediterranean areas - The weathering and pedogenetic evolution on limestones in mediterranean areas leads to the formation of a more or less decarbonated red soil. This evolution passes through successive stages of decarbonatation, rubification and decalcification and can be associated with a colour change, which includes lithochromic, brown and red phases. It is obviously influenced by the hydrodynamic properties of the soils and by the underground drainage characteristics of the substratum: hence soils developed over almost impermeable marly limestones remain at the lithochromic and/or brown levels, and decarbonatation remains weak; on hard and fractured limestones, pedogenesis is much more active and, even if the weathering volume on this rather pure rocks is small, the soil profile becomes almost completely devoid of free lime; under certain conditions a slight decalcification of the soil sorption complex may even be observed.

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Turner S. J. , Flindell P. A. , Hendri D. , Hardjana I. , Lauricella P. F. , Lindsay R. P. , Marpaung B. , White G. P. ,
The Ratatotok district in the Minahasa Regency of North Sulawesi, Indonesia is an area of significant gold mineralisation. Gold has been mined in the district since at least the 1850s, and intensively by the Dutch between 1900 and 1921 with a recorded production of 5,060 kg of gold. Newmont began exploring the district in 1986, and has delineated a major sediment-hosted replacement-style deposit at Mesel, and other smaller deposits in an 8 X 5 km area. A total drill-indicated resource of over 60 metric tonnes of gold ( 2 Moz) is reported for Mesel, and three of the smaller deposits. Approximately 80% of this resource is refractory. Silver grades are usually low (< 10 g/t). The Mesel deposit is similar to many Carlin-type deposits in carbonate hostrocks, alteration, geochemical signature and ore mineralogy, but is distinct in tectonic setting. The discovery of replacement-style mineralisation at Mesel, in an impure limestone within a Tertiary island arc environment, demonstrates that deposits with outward characteristics similar to Carlin-type mineralisation are not restricted to a continental setting. Carbonate sediments in the Ratatotok district were deposited in a Late Miocene restricted basin. Later compressional tectonics caused uplift that resulted in karst development in the limestone and erosion of the adjacent volcanic arc with deposition of a thick epiclastic unit. This was followed by intrusion of shallow level pre-mineral andesite into the sequence. Mineralisation at Mesel, and probably elsewhere in the district, is synchronous with the late-stage reactivation of strike-slip faults. Mineralising fluids at Mesel were focussed along steep structures sympathetic to these faults, and trapped below a relatively impermeable andesite cap rock. Hydrothermal fluids caused decalcification of the silty, more permeable carbonate units with the formation of secondary dolomite, deposition of fine arsenian pyrite, silica veinlets and gold. Volume loss due to decalcification and dolomite formation caused collapse brecciation which enhanced fluid flow and further mineralisation. This locally culminated in total decarbonation and deposition of massive silica. Late-stage stibnite occurs in structural zones within the ore deposit, whereas arsenic (as realgar and orpiment) and mercury (as cinnabar) are concentrated on the periphery. Elsewhere in the Ratatotok district, gold mineralisation is restricted to replacement-style mineralisation in permeable zones along limestone-andesite contacts, open-space-filling quartz-calcite veins and stockworks, and residual quartz-clay breccias. The residual breccias are developed in-situ, and are interpreted to form by dissolution of the wallrock limestone from around pre-existing mineralisation. This has resulted in widespread eluvial gold occurrences

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Jones B. ,
The twilight zone of a cave, an environment transitional between the well-illuminated environment outside the cave and the dark environment of the cave interior, is one of the most unusual microenvironments of the karst terrain. Walls in the twilight zone of caves on Grand Cayman and Cayman Brac are coated with a biofilm that incorporates a diverse assemblage of epilithic microbes and copious mucus. Most microbes are different from those found elsewhere in the karst terrains of the Cayman Islands, probably because they have adapted to life in the poorly illuminated twilight zone. None of the microbes employ an endolithic life mode, and less than 10% of them show evidence of calcification. The biofilm does, however, provide a medium in which a broad spectrum of destructive and constructive processes operate. Etching, the dominant destructive process, produces residual dolomite, residual calcite, blocky calcite, and spiky calcite. Constructive processes include precipitation of calcite, dolomite, gypsum, halite, and sylvite. Although filamentous microbes are common, examples of detrital grains trapped and bound to the substrate are rare. Destructive processes are more common than constructive ones

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Jones B. , Kahle C. F. ,
Cavities in the dolostones of the Cayman Formation (Miocene) on Grand Cayman and Cayman Brac commonly contain spar calcite cements and/or a variety of exogenetic (derived from sources external to the bedrock) and endogenetic (derived from sources in the bedrock) internal sediments. Micrite is a common component in many of these internal sediments. The exogenetic micrite, which is typically laminated and commonly contains fragments of marine biota, originated from the nearby shallow lagoons. The endogenetic micrite formed as a residue from the breakdown of spar calcite crystals by etching, as constructive and destructive envelopes developed around spar calcite crystals, by calcification of microbes, by breakdown of calcified filamentous microbes, and by precipitation from pore waters. Once produced, the endogenetic micrite may be transported from its place of origin by water flowing through the cavities. Endogenetic micrite can become mixed with the exogenetic micrite. Subsequently, it is impossible to recognize the origin of individual particles because the particles in endogenetic micrite are morphologically like the particles in exogenetic micrite. Formation of endogenetic micrite is controlled by numerous extrinsic and intrinsic parameters. In the Cayman Formation, for example, most endogenetic micrite is produced by etching of meteoric calcite crystals that formed as a cement in the cavities or by microbial calcification. As a result, the distribution of the endogenetic micrite is ultimately controlled by the distribution of the calcite cement and/or the microbes-factors controlled by numerous other extrinsic variables. Irrespective of the factors involved in its formation, it is apparent that endogenetic micrite can be produced by a variety of processes that are operating in the confines of cavities in karst terrains

Laltration de type "fantme de roche" : processus, volution et implications pour la karstification, 2011,
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Quinif Yves, Bruxelles Laurent

Depuis plusieurs années, de nombreux exemples de fantômes de roche ont été reconnus dans les karsts en Belgique, en France et en Italie. Ils correspondent à des poches ou à des couloirs de décalcification emplis d’altérite in situ. Leur genèse relève d’un cas spécial de karstification où, à l’inverse des phénomènes de karstification par enlèvement total, le résidu insoluble ou moins soluble reste en place et forme un squelette qui mime la structure initiale de la roche (fossiles, joints, lits de chailles, etc.). Cette altérite, qui peut également se développer sous une voûte calcaire, forme un vaste réseau interconnecté et calé sur la fracturation. De fait, elle constitue une discontinuité importante au sein des massifs karstiques. Lorsque le niveau de base s’abaisse, l’altérite s’effondre sur elle-même puis elle est érodée par des circulations souterraines qui se mettent en place à son toit. Des réseaux de galeries mais aussi des formes de surface se forment alors rapidement, essentiellement par évidement de l’altérite. Ce phénomène est maintenant reconnu dans le monde entier, affectant tous les types de roches, carbonatées ou non.

For several years, numerous examples of ghost rocks have been recognised in karst areas in Belgium, in France and in Italy. They correspond to decalcified pockets but also to decalcified corridors filled with in-situ alterite. It is a special case of karstification where a non-soluble skeleton remains and preserves the structures of the initial rock (fossils, joints, levels of cherts, etc.). This alterite, which can also be formed under a safe roof, draws a large maze following the tectonic patterns. It constitutes an important discontinuity inside the karstic areas. When the base level drops, the structure of the alterite collapses and a void is formed on his top. Then runoff can use this void and erode the soft alterite. Cave network but also surface features can develop quickly, mainly by the cleaning of the alterite. Now, some examples of this phenomenon have been recognised all around the world and occur in different sorts of rocks, carbonated or not.

The nature and origin of the ghost-rocks at Bullslaughter Bay, South Wales, 2012,
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Rowberry Matt D. , Battiauqueney Yvonne, Blazejowski Blazej, Walsh Peter

The ‘ghost-rocks’ of the British Isles have attracted very little research interest over the years despite being widely distributed. In South Wales, the ghost-rocks of the Pembroke Peninsula are usually associated with the mudrock formations immediately above and below the Carboniferous Limestone. This study focuses on their nature and origin through a detailed investigation of the cliff sections at Bullslaughter Bay. The investigated ghost-rocks are associated with a suite of breccias, collectively termed the Gash Breccias. These are an enigmatic suite of around twenty-five large breccia masses located exclusively in the eastern part of the peninsula. They comprise huge masses of coarse, chaotic, clast-supported, monomictic breccia and represent highly disturbed features in the otherwise unbroken sequences of Carboniferous Limestone. Their origin may be karstic, tectonic, or a combination of the two. They could, theoretically, have formed at any point between the end of the Carboniferous and the Pliocene. If their origin is karstic, it cannot yet be determined if the processes were attributable to per descensum or per ascensum groundwater systems. If tectonic, it is not known whether they formed during periods of compression or extension. From our own geological and geophysical fieldwork, we believe that the breccias originated as a result of subterranean karstic processes whilst retaining an open mind with regard to the role played by tectonics. The breccia and ghost-rocks are both displayed in fine cliff exposures around Bullslaughter Bay. These sections, although not extensive, are extremely instructive. The processes that generate ghost-rock result in isovolumetric weathering of the host rock and an associated loss of density and strength. They may or may not involve the removal of certain chemical constituents in the regolith through solution and hydrolysis followed by the formation of secondary minerals, frequently clay. In reality, the precise weathering process differs according to the type of rock. The process is controlled by the permeability of each rock type in banded rocks such as mudstones or shale with banded chert whereas it is controlled by fissures and faults in homogenous rocks. This control is clearly seen in the Carboniferous Limestone around Bullslaughter Bay, where ghost-rocks are present, more commonly in case of impure or dolomitic limestone. At present, it is not clear whether the groundwater movements were caused by hydrothermal or meteoric processes and this forms the basis of ongoing research. Finally, the study considers the relationship that exists between the ghost-rock and the Gash Breccia. We examine whether there is a logical correlation between the processes that came to generate the ghost-rock and the processes responsible for the generation of the breccia. It may then be possible to accurately state whether the ghost-rock formed before, during, or after, the breccia. The reasons that the ghost-rocks of the British Isles have attracted very little research interest may stem from the fact that they have no current commercial value, have seldom presented engineering problems, and are normally difficult to date. It is clear that numerous karst related sag-subsidences in the British Isles result from the large-scale decalcification of the Carboniferous Limestone (e.g. the Tortonian Brassington Formation of the southern Pennines). There is, however, an increasingly large body of evidence to suggest that these subsidences result from the same processes that generate ghost-rock rather than those that create endokarstic voids. The subsidences may preserve stratigraphical sequences several decametres thick and reach depths and widths of many hectometres. Unfortunately, the masses of decalcified limestone below the Tortonian sediments are of no commercial interest and have hardly ever been penetrated by boreholes. Therefore, we do not know exactly what underlies the karstic fills. The possibility that most of these structures are best explained as the result of per ascensum groundwater flow is discussed.

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