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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 freezing point is the point at which a liquid solidifies [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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Your search for mechanisms (Keyword) returned 221 results for the whole karstbase:
Showing 1 to 15 of 221
Recharge of Phreatic Aquifers in (Semi-)Arid Areas, ,
Groundwater use is of fundamental importance to meet the rapidly expanding urban, industrial and agricultural water requirements in (semi) arid areas. Quantifying the current rate of groundwater recharge and define its variability in space and time are thus prerequesites for efficient groundwater resource managment in these regions, where such resources are often the key to economic development. Attention focuses on recharge of phreatic aquifers, often the most readily-available and affordable source of water in (semi) arid regions. These aquifers are also the most susceptible to contamination, with the recharge rate determining their level of vulnerability. (Semi) arid zone recharge can be highly variable, the greater the aridity, the smaller and potentially more variable the natural flux. Its determination is an iterative process, involving progressive data collection and resource evaluation; there is also a need to use more than one technique to verify results. Direct, localised and indirect recharge mechanisms from a spectrum of known sources are addressed in the framework of recharge from precipitation, intermittant flow and permanent water bodies. The approach taken for each of these reflects the nature and current understanding of the processes involved. The volume also reviews current recharge estimation challenges, outlines recent developments and offers guidance for potential solutions.

Sulfate reducing bacteria in microbial mats: Changing paradigms, new discoveries, 0000, Baumgartner Lk, Reid Rp, Dupraz C, Decho Aw, Buckley Dh, Spear Jr, Przekop Km, Visscher Pt,
Sulfate reducing bacteria (SRB) have existed throughout much of Earth's history and remain major contributors to carbon cycling in modern systems. Despite their importance, misconceptions about SRB are prevalent. In particular, SRB are commonly thought to lack oxygen tolerance and to exist only in anoxic environments. Through the last two decades, researchers have discovered that SRB can, in fact, tolerate and even respire oxygen. Investigations of microbial mat systems have demonstrated that SRB are both abundant and active in the oxic zones of mats. Additionally, SRB have been found to be highly active in the lithified zones of microbial mats, suggesting a connection between sulfate reduction and mat lithification. In the present paper, we review recent research on SRB distribution and present new preliminary findings on both the diversity and distribution of [delta]-proteobacterial SRB in lithifying and non-lithifying microbial mat systems. These preliminary findings indicate the unexplored diversity of SRB in a microbial mat system and demonstrate the close microspatial association of SRB and cyanobacteria in the oxic zone of the mat. Possible mechanisms and further studies to elucidate mechanisms for carbonate precipitation via sulfate reduction are also discussed

Preference responses and tolerances of the troglobitic Carabid Beetle, Rhadine subterranea., 1971, Mitchell Robert W.
Studies were made on the preference responses and tolerances of the troglobitic carabid beetle Rhadine subterranea to light, temperature, and relative humidity. The beetles are weakly photonegative and appear to have a strong preference far atmospheres of low saturation deficit. Both these responses seem to be orthokineses. They have a strongly developed temperature sense, and their temperature preferendum shifts seasonally. This response seems to be a klinotaxis. They are neither strongly stenothermal nor stenohygrobic. The preference responses, especially that of temperature, are probably mechanisms tending to restrict the beetles to their habitat. The tolerance data suggest that the epigeum could, at times, be used as a dispersal route.

Preference responses and tolerances of the troglobitic Carabid Beetle, Rhadine subterranea., 1971, Mitchell Robert W.
Studies were made on the preference responses and tolerances of the troglobitic carabid beetle Rhadine subterranea to light, temperature, and relative humidity. The beetles are weakly photonegative and appear to have a strong preference far atmospheres of low saturation deficit. Both these responses seem to be orthokineses. They have a strongly developed temperature sense, and their temperature preferendum shifts seasonally. This response seems to be a klinotaxis. They are neither strongly stenothermal nor stenohygrobic. The preference responses, especially that of temperature, are probably mechanisms tending to restrict the beetles to their habitat. The tolerance data suggest that the epigeum could, at times, be used as a dispersal route.

Flow of fossil groundwater, 1977, Bourdon Dj,
The great groundwater basins of North Africa and Arabia extend over an area of some 6.5 million square kilometres. Gradients on the isopiezometric surfaces of their confined ground-waters are generally interpreted as indicating present-day flow of groundwater. Can such flow occur in basins where most or all of the groundwater is fossil and where effective infiltration and recharge may have ceased some 10 000 years ago? Assuming that there is indeed no current recharge in these arid and sem-arid regions, the paper identifies seven groups totalling 12 possible mechanisms which can contribute in varying degrees to maintaining flow of groundwater long after effective recharge has ceased. These are: (i) Residual heads; (ii) Tilting of basin; (iii) Compaction effects, in terms of sediment loading, basalt loading and water loading/unloading; (iv) Thermal drive; (v) Gas drive; (vi) Lowering of discharge level, by tectonic displacement, by pressure bursts and by collapse of cover; and (vii) Evaporation in the discharge zone, such as lowering of lake levels and evaporation from sabkhas. Nine additional mechanisms were considered but rejected. Combinations of these mechanisms can produce heads inducing flow of fossil groundwater, but appear to be insufficient to account for present hydraulic regimes without some current surface recharge. The findings have direct application to studies leading to the development, use and management of these major water resources of the arid zones of the Sahara and Arabia

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

Water Chemistry of the Atea Kananda and the Related Drainage Area, 1980, James, Julia M.

The Ca2+, Mg2+, alkalinity, pH and temperature have been measured in water from the Atea Kananda cave and related surface sites on the Muller Plateau (Papua New Guinea). A wide variation in the Ca2+ and Mg2+ values was found and this has been attributed to the lithology and nature (open or closed) of the water courses. From alkalinity measurements anions other than bicarbonate, probably sulphate are expected to be present in significant quantities in the cave waters. Most of the waters are aggressive. The Ca2+/Mg2+ x 10 ratio is shown to be a useful tool in predicting the origin of unknown waters in the cave. The variations of the measured and calculated parameters for groups of related surface and underground sites are presented and discussed. Tentative solution erosion rates for the Muller Plateau have been calculated and the conclusion reached that where the erosion can be placed as largely occuring on pure limestone these are high. Impure limestones and non-calcareous rocks in their catchments give anomalously low results for the main rivers. A scheme for cave development on the Muller Plateau by solution mechanisms is presented.


Underground Streams on Acid Igneous Rocks in Victoria, 1981, Finlayson, Brian

Underground streams occur in valley floors on acid igneous rocks over a wide area of eastern Victoria. In some cases the underground passage is capable of accommodating all streamflow levels so that there is no active surface channel. Three of them contain passages accessible to cavers. The literature contains very few references to features of this kind and there is some confusion as to whether they should be called 'pseudokarst'. Detailed descriptions and diagrams are presented for two of the sites, Labertouche and Brittania Creek. At North Maroondah, sinking streams on dacite have caused complications for hydrological experiments. Possible origins of these features are discussed and it is obvious that several mechanisms are feasible. One of the difficulties in determining modes of formation is that a variety of processes could lead to very similar end products. Three main theories on the mode of formation are suggested.


Granite Caves in Girraween National Park, South-East Queensland, 1982, Finlayson, Brian

Four caves and two underground streams in granite occur within the Girraween National Park. Only two of these sites have previously been reported. They mainly occur on the margins of major joints in the granite where streams descend into troughs along the joints. The caves are themselves formed in minor joints. In some cases streams have worked their way down from the surface along a joint but at three of the sites streams flow through horizontal joints in the granite which have not been opened from the surface. For these sites it is not clear how the initial passage was opened up underground. The two possible mechanisms suggested here are solution and joint opening following pressure release. The cave morphology clearly indicates that once the path flow is open, abrasion becomes the major process. Flowstone terraces, 'cave coral', and cemented gravels are found in the caves. The speleothems and the cement are amorphous silica (Opal A). Caves in granite may be more common than was previously thought.


Growth mechanisms of speleothems in Castleguard Cave, Columbia Icefields, Alberta, Canada, 1983, Atkinson T. C.

Time-Keeping Mechanisms and Their Ecological Significance in Cavernicolous Animals, 1985, Lamprecht Gnther, Weber Friedrich

Shallow-marine carbonate facies and facies models, 1985, Tucker M. E. ,
Shallow-marine carbonate sediments occur in three settings: platforms, shelves and ramps. The facies patterns and sequences in these settings are distinctive. However, one type of setting can develop into another through sedimentational or tectonic processes and, in the geologic record, intermediate cases are common. Five major depositional mechanisms affect carbonate sediments, giving predictable facies sequences: (1) tidal flat progradation, (2) shelf-marginal reef progradation, (3) vertical accretion of subtidal carbonates, (4) migration of carbonate sand bodies and (5) resedimentation processes, especially shoreface sands to deeper subtidal environments by storms and off-shelf transport by slumps, debris flows and turbidity currents. Carbonate platforms are regionally extensive environments of shallow subtidal and intertidal sedimentation. Storms are the most important source of energy, moving sediment on to shoreline tidal flats, reworking shoreface sands and transporting them into areas of deeper water. Progradation of tidal flats, producing shallowing upward sequences is the dominant depositional process on platforms. Two basic types of tidal flat are distinguished: an active type, typical of shorelines of low sediment production rates and high meteorologic tidal range, characterized by tidal channels which rework the flats producing grainstone lenses and beds and shell lags, and prominent storm layers; and a passive type in areas of lower meteorologic tidal range and higher sediment production rates, characterized by an absence of channel deposits, much fenestral and cryptalgal peloidal micrite, few storm layers and possibly extensive mixing-zone dolomite. Fluctuations in sea-level strongly affect platform sedimentation. Shelves are relatively narrow depositional environments, characterized by a distinct break of slope at the shelf margin. Reefs and carbonate sand bodies typify the turbulent shelf margin and give way to a shelf lagoon, bordered by tidal flats and/or a beach-barrier system along the shoreline. Marginal reef complexes show a fore-reef--reef core--back reef facies arrangement, where there were organisms capable of producing a solid framework. There have been seven such phases through the Phanerozoic. Reef mounds, equivalent to modern patch reefs, are very variable in faunal composition, size and shape. They occur at shelf margins, but also within shelf lagoons and on platforms and ramps. Four stages of development can be distinguished, from little-solid reef with much skeletal debris through to an evolved reef-lagoon-debris halo system. Shelf-marginal carbonate sand bodies consist of skeletal and oolite grainstones. Windward, leeward and tide-dominated shelf margins have different types of carbonate sand body, giving distinctive facies models. Ramps slope gently from intertidal to basinal depths, with no major change in gradient. Nearshore, inner ramp carbonate sands of beach-barrier-tidal delta complexes and subtidal shoals give way to muddy sands and sandy muds of the outer ramp. The major depositional processes are seaward progradation of the inner sand belt and storm transport of shoreface sand out to the deep ramp. Most shallow-marine carbonate facies are represented throughout the geologic record. However, variations do occur and these are most clearly seen in shelf-margin facies, through the evolutionary pattern of frame-building organisms causing the erratic development of barrier reef complexes. There have been significant variations in the mineralogy of carbonate skeletons, ooids and syn-sedimentary cements through time, reflecting fluctuations in seawater chemistry, but the effect of these is largely in terms of diagenesis rather than facies

Evidence for karstic mechanisms involved in the evolution the Moroccon hamadas., 1986, Castellani Vittorio, Dragoni Walter
Underground tubular karst features, observed in an arid envinronment of southern Morocco, are described. On the basis of various evidences, it is suggested that such features were originated mainly by condensation water. A computation of the time necessary for their formation supports this hypothesis.

Le karst du massif des Calanques (Marseille Cassis), 1988, Blanc J. J. , Monjeau R.
THE KARST OF THE CALANQUES massif - Description of karstic morphology in relation to lithology and tectonic framework; actual hydrography. Sedimentary analysis applied to speleothems (calcitic deposits, hardened silts with rubefaction, upper stalagmitic layers, eolianites). Relations with some recent tectonic mechanisms. Hydrogeology: marine resurgences, subterranean rivers (Port-Miou and Le Bestouan).

Pseudosinella revisited (Collembola, Entomobryinae), 1988, Christiansen Kenneth, Moberg Thomas
Eight controversies are active in the study of macroevolution. These are: 1) the meaning of the term macroevolution, 2) the role of chance, 3) the role of stasis and gradualism, 4) whether significant change Is Iimited to speciation events, 5) the environmental conditions where macroevolutionary change occurs, 6) whether Neodarwinian mechanisms are adequate to explain change, 7) the existence and nature of hierarchical evolutonary processes, and 8) Darwin's views about all this. After a brief examination of each of these issues we used the extensive data available for 9 species of European and Nearctic cave Pseudosinella to examine the third, fourth and fifth controversies mentioned above. Our conclusions are that while we are unable to demonstrate ongoing directional selection, we have clear evidence that significant adaptive change is not limited to speciation events. It does however appear that the amount of adaptive change is greater in the process of speciation than in between. We also show that there is no evidence for clear periods of stasis in the evolution of these forms. This leads us to a new model of the macroevolutionary process combining features of gradualism and punctuated equilibrium. We also showed that evolutionary change Is not associated with unstable environments but rather with more stable ones.

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