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Featured articles from Cave & Karst Science Journals
Characterization of minothems at Libiola (NW Italy): morphological, mineralogical, and geochemical study, Carbone Cristina; Dinelli Enrico; De Waele Jo
Chemistry and Karst, White, William B.
The karst paradigm: changes, trends and perspectives, Klimchouk, Alexander
Long-term erosion rate measurements in gypsum caves of Sorbas (SE Spain) by the Micro-Erosion Meter method, Sanna, Laura; De Waele, Jo; Calaforra, José Maria; Forti, Paolo
The use of damaged speleothems and in situ fault displacement monitoring to characterise active tectonic structures: an example from Zapadni Cave, Czech Republic , Briestensky, Milos; Stemberk, Josef; Rowberry, Matt D.;
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 glacier (Keyword) returned 98 results for the whole karstbase:
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Ice and speleothems are widely regarded as mutually exclusive as the presence of liquid water is a fundamental prerequisite for speleothem deposition. Here we show that speleothems may form in caves overlain by a glacier, as long as the temperature in the cave is above freezing and the conduits are not completely flooded by melt water. Carbonate dissolution is accomplished via sulfide oxidation and the resultant speleothems show high [delta]13C values approaching and locally exceeding those of the parent host rock (lack of soil-derived biogenic C). The [delta]18O values reflect the isotopic composition of the melt water percolating into the karst fissure network and carry an atmospheric (temperature) signal, which is distinctly lower than those of speleothems formed during periods when soil and vegetation were present above the cave. These `subglacial' speleothems provide a means of identifying and dating the former presence of warm-based paleoglaciers and allow us to place some constraints on paleotemperature changes
The sympatric occurrence of two bathynellids previously considered races of Bathynella natans; natans and stammeri; is evaluated as a natural ecological-genetic experiment. Since no hybrids appear in mixed populations, these forms are proven to be full species: Bathynella natans Vejdovsky and Bathynella stammeri (Jakobi). Besides the form of the mandibles, which until now was the only taxonomically useful diagnostic character in the genus Bathynella, 7 additional, suitably applicable morphological characters have been found (Table 3). The Bathynella biotope investigated is assigned to the "eustygopsammal" subterranean life province (Husmann 1966), which is associated with the "Parastenocaris-Bathynella" biocoenosis (Husmann 1962). This particular biocoenosis is evidently resistant to organic pollution of ground water. The sympatric existence of Bathynella natans and B.stammeri can be explained by consideration of the geo-limnological developmental history of the interstitial zone of the North German low plain. Sands and gravels were widely deposited in the North German Basin by northward-retreating glaciers, creating microcavernous living space and passages for the interstitial fauna. This microfauna could find passages in layers of sand under and along the northward-flowing streams. Primitive Ice-Age streams (,,Urstromtàler" of Keilhack) formed east-to-west cross-connections between the south-north distributional corridors. The great geographical expansion of the tributary river courses which reached the north German plain before, during, and after the Ice Age suggests that ground water habitats were temporarily separated and later rejoined by orogenic movements of the earth's surface. Such an orogenically caused, geomorphological isolation lasting for a sufficiently long geological period could have led to the result that species, originating in isolation from the same phylogenetic stock, subsequently were brought together again in the same biotope. This is particularly true for bathynellids, which as archaic types (Lebensformtypen) of the ancient, extreme "mesopsammal" biotope (Remane) are quite likely to have become sympatric in such a manner.
The sympatric occurrence of two bathynellids previously considered races of Bathynella natans; natans and stammeri; is evaluated as a natural ecological-genetic experiment. Since no hybrids appear in mixed populations, these forms are proven to be full species: Bathynella natans Vejdovsky and Bathynella stammeri (Jakobi). Besides the form of the mandibles, which until now was the only taxonomically useful diagnostic character in the genus Bathynella, 7 additional, suitably applicable morphological characters have been found (Table 3). The Bathynella biotope investigated is assigned to the "eustygopsammal" subterranean life province (Husmann 1966), which is associated with the "Parastenocaris-Bathynella" biocoenosis (Husmann 1962). This particular biocoenosis is evidently resistant to organic pollution of ground water. The sympatric existence of Bathynella natans and B.stammeri can be explained by consideration of the geo-limnological developmental history of the interstitial zone of the North German low plain. Sands and gravels were widely deposited in the North German Basin by northward-retreating glaciers, creating microcavernous living space and passages for the interstitial fauna. This microfauna could find passages in layers of sand under and along the northward-flowing streams. Primitive Ice-Age streams (,,Urstromtàler" of Keilhack) formed east-to-west cross-connections between the south-north distributional corridors. The great geographical expansion of the tributary river courses which reached the north German plain before, during, and after the Ice Age suggests that ground water habitats were temporarily separated and later rejoined by orogenic movements of the earth's surface. Such an orogenically caused, geomorphological isolation lasting for a sufficiently long geological period could have led to the result that species, originating in isolation from the same phylogenetic stock, subsequently were brought together again in the same biotope. This is particularly true for bathynellids, which as archaic types (Lebensformtypen) of the ancient, extreme "mesopsammal" biotope (Remane) are quite likely to have become sympatric in such a manner.
Using Plummer et al.'s [11] rate equations on the dissolution and deposition of CaCO3 in H2O---CO2 systems, we have calculated deposition rates of CaCO3 to stalagmites in caves which are covered by glaciers or bare karst. In this case no biogenic CO2 from vegetated soil is available and the deposition of CaCO3 involves only atmospheric CO2. The mechanism of deposition proceeds by a temperature effect. Cold melting waters of about 0[deg]C dissolve CaCO3 under open system conditions at the surface of the rock. When this solution saturated with respect to CaCO3, flows through the limestone rock its temperature increases by several degrees. Therefore, it becomes supersaturated, and CaCO3 is deposited under open system conditions in the warmer cave. Maximal growth rates of about 10-3 cm/year are possible. From the kinetics of the deposition of CaCO3 from the thin water films present at the surface of stalagmites we are able to estimate the isotopic composition of carbon in the CaCO3 deposited on the stalagmites to be approximately [delta]13C = %, which is close to some observed values.From our data we conclude that substantial growth of stalagmites is possible during glacial periods as well as in areas of bare karst, a question which was not resolved up to now
THE UNDERGROUND SYSTEM OF PLATEAU DU SORNIN (VERCORS, FRANCE): THE GOUFFRE BERGER AND THE SCIALET DE LA FROMAGERE - Gouffre Berger (-1198m) and Scialet de La Fromagère (-902m) are the two main drains of an important underground complex, which develops 26 km inside Sornin table-land, massif du Vercors, Isère. The glaciers have left deep prints in the surface morphology (Schichttreppenkarst) and have played an important role in the genesis of the underground complex of Sornin. Most of morphological elements and dated witnesses (speleothems) testify to the primacy of this morphoclimatic term. Under present bioclimatic conditions (discontinuous forest - Raw weather climate, T? = 4?C, P = 1700mm), the specific dissolution is estimated to 120mm/ky. This dissolution is important in winter (2,5 times more than in summer). Sornin plateau belongs to an intermediary case between forests mountainous karsts and high karsts regarding the spatial distribution of the dissolution.
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 Würm; fluvio-glacial up-building of the Torcieu watergap and correlated water logging of the lower karst during Würm and Tardiglacial periods; probable direct action of glaciers during the Riss.
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