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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. ...

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That alluvial plain is a plain formed by the deposition of water borne sediments [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.
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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 cave walls (Keyword) returned 47 results for the whole karstbase:
Showing 1 to 15 of 47
Geomorphology of Barber Cave, Cooleman Plain, New South Wales, 1968, Jennings, J. N.

Barber Cave is one of the Cooleman Plain caves known for a long time. Inscriptions on the cave walls take white man's knowledge of it at least back to 1875 when it was visited by a party led by John Gale of Queanbeyan. However, the actual date of discovery remains obscure and may belong to the period of the late 1830s to the early 'fifties when there were convict and ex-convict stockmen looking after T.A. Murray's (later Sir Terence Murray) stock on the plain. It is of modest dimensions with about 335m (1,100 ft) of passage, some 25m (80 ft) of overall height, and no spaces worthy of the name chamber. Within this small compass, nevertheless, it possesses such a good range of cave forms that it was selected o represent "karst cave" in the series of landform prototypes being described and illustrated briefly for teaching purposes in the Australian Geographer (Jennings, 1967b). Here a fuller account of its morphology is presented for speleologists.

A preliminary note on the spatial distribution of Meta menardi, Triphosa dubitata, Triphosa sabaudiata, Nelima aurantiaca and Culex pipiens within a cave ecosystem (Grotte de la Scierie: Haute-Savoie)., 1976, Bourne John D.
Following 8 months of observations in a richly populated cave, (Grotte de la Scierie, HauteSavoie, France), it has been possible to outline the movements and distribution of Meta menardi (Araneae), Nelima aurantiaca (Opiliones), Triphosa dubitata and Triphosa sabaudiata (Lepidoptera) and Culex pipiens (Diptera) within the cave ecosystem. Although no general rule can be postulated it appears that the morphology of the cave walls and the climatic conditions regulate the distribution of these 5 species within the cave ecosystem. The interactions between the 5 species have been investigated.

An Investigation of the Climate, Carbon Dioxide and Dust in Jenolan Caves, N.S.W., PhD Thesis, 1997, Michie, Neville

Pressure of use of Jenolan Caves as a tourist spectacle has raised concerns about the wellbeing of the caves, so three related physical subjects were reviewed and investigated; the cave microclimate, the carbon dioxide in the cave atmosphere and dustfall in the caves. The microclimate has been shown to be dominated by several physical processes: in the absence of air movement, conduction and radiation dominate; in association with air movement, convective coupled heat and mass transfer tends to dominate energy flows. A new approach using boundary conditions and qualitative characteristics of transient fronts enables accurate measurement and analysis of energy, heat and mass transfer. This technique avoids the dimensionless number and transfer coefficient methods and is not geometrically sensitive. Conditions in caves are also determined by the capillary processes of water in cave walls. Air movement in caves depends on surface weather conditions and special problems of surface weather observation arise. A series of experiments were undertaken to evaluate the cave and surface processes. The physical processes that collect, transport and release dust were measured and described. Dust in the caves was shown to be carried from the surface, mainly by visitors. The concept of the Personal Dust Ooud is developed and experimental measurements and analysis show that this process is a major threat to the caves. New techniques of measurement are described. An accurate physiological model has been developed which predicts most of the carbon dioxide measured in Jenolan Caves, derived mainly from visitors on the cave tours. This model, developed from previously published human physiological information also predicts the production of heat and water vapour by cave tourists. The effects of carbon dioxide on cave conditions has been investigated. Details of a two year program of measurements in the caves are given. The generalised approach and methods are applicable to other caves, mines and buildings.

Hydrobasaluminite and Aluminite in Caves of the Guadalupe Mountains, New Mexico, 1998, Polyak, V. J. , Provencio, P.
Hydrobasaluminite, like alunite and natroalunite, has formed as a by-product of the H2S-H2SO4 speleogenesis of Cottonwood Cave located in the Guadalupe Mountains of New Mexico. This mineral is found as the major component of white pockets in the dolostone bedrock where clay-rich seams containing kaolinite, dickite, and illite have altered during speleogenesis to hydrobasaluminite, amorphous silica, alunite, and hydrated halloysite (endellite). Gibbsite and amorphous silica are associated with the hydrobasaluminite in a small room of Cottonwood Cave. Opalline sediment on the floor of this room accumulated as the cave passage evolved. Jarosite, in trace amounts, occurs in association with the opalline sediment and most likely has the same origin as hydrobasaluminite and alunite. The hydrobasaluminite was found to be unstable at 25C and 50% RH, converting to basaluminite in a few hours. Basaluminite was not detected in the cave samples. Aluminite has precipitated as a secondary mineral in the same small room where hydrobasaluminite occurs. It comprises a white to bluish-white, pasty to powdery moonmilk coating on the cave walls. The bedrock pockets containing hydrobasaluminite provide the ingredients from which aluminite moonmilk has formed. It appears that recent cave waters have removed alumina and sulfate from the bedrock pocket minerals and have deposited aluminite and gypsum along the cave wall. Gypsum, amorphous silica and sulfate-containing alumina gels are associated with the aluminite moonmilk.

Diagenetic concretions from the cave clastic sediment, Cave in Tounj quarry, Croatia, 1998, Lackovič, Damir

Diagenetic concretions from Cave in Tounj quarry (central Croatia) are studied. Concretions are found in non-cemented unsorted clastic cave deposit. They consist of particles of different size (clay to pebble) and from different provenance. One part of calcite and clay minerals are coming from speleothems and cave walls limestone. Detrital particles: chert, quartz, muscovite, chlorite, ilmenite, magnetite and most of clay, are probable transported into the cave from Triassic and Pleistocene clastic sediments from the surface. Autochthonous constituents of concretions are limonitic pizoids and some calcite cement. Composition of concretion is similar to the composition of surrounding non-cemented sediment.

Microbiology and geochemistry in a hydrogen-sulphide-rich karst environment, 2000, Hose Louise D. , Palmer Arthur N. , Palmer Margaret V. , Northup Diana E. , Boston Penelope J. , Duchene Harvey R. ,
Cueva de Villa Luz, a hypogenic cave in Tabasco, Mexico, offers a remarkable opportunity to observe chemotrophic microbial interactions within a karst environment. The cave water and atmosphere are both rich in hydrogen sulphide. Measured H2S levels in the cave atmosphere reach 210 ppm, and SO2 commonly exceeds 35 ppm. These gases, plus oxygen from the cave air, are absorbed by freshwater that accumulates on cave walls from infiltration and condensation. Oxidation of sulphur and hydrogen sulphide forms concentrated sulphuric acid. Drip waters contain mean pH values of 1.4, with minimum values as low as 0.1.The cave is fed by at least 26 groundwater inlets with a combined flow of 200-300 l/s. Inlet waters fall into two categories: those with high H2S content (300-500 mg/l), mean PCO2=0.03-0.1 atm, and no measurable O2; and those with less than 0.1 mg/l H2S, mean PCO2=0.02 atm, and modest O2 content (up to 4.3 mg/l). Both water types have a similar source, as shown by their dissolved solid content. However, the oxygenated water has been exposed to aerated conditions upstream from the inlets so that original H2S has been largely lost due to outgassing and oxidation to sulphate, increasing the sulphate concentration by about 4%. Chemical modelling of the water shows that it can be produced by the dissolution of common sulphate, carbonate, and chloride minerals.Redox reactions in the cave appear to be microbially mediated. Sequence analysis of small subunit (16S) ribosomal RNA genes of 19 bacterial clones from microbial colonies associated with water drips revealed that 18 were most similar to three Thiobacilli spp., a genus that often obtains its energy from the oxidation of sulphur compounds. The other clone was most similar to Acidimicrobium ferrooxidans, a moderately thermophilic, mineral-sulphide-oxidizing bacterium. Oxidation of hydrogen sulphide to sulphuric acid, and hence the cave enlargement, is probably enhanced by these bacteria.Two cave-enlarging processes were identified. (1) Sulphuric acid derived from oxidation of the hydrogen sulphide converts subaerial limestone surfaces to gypsum. The gypsum falls into the cave stream and is dissolved. (2) Strongly acidic droplets form on the gypsum and on microbial filaments, dissolving limestone where they drip onto the cave floors.The source of the H2S in the spring waters has not been positively identified. The Villahermosa petroleum basin within 50 km to the northwest, or the El Chichon volcano [small tilde]50 km to the west, may serve as source areas for the rising water. Depletion of 34S values (-11.7[per mille sign] for sulphur stabilized from H2S in the cave atmosphere), along with the hydrochemistry of the spring waters, favour a basinal source

Acidic cave-wall biofilms located in the Frasassi Gorge, Italy, 2000, Vlasceanu L. , Sarbu S. M. , Engel A. S. , Kinkle B. K. ,
Acidic bioflms present on cave walls in the sulfidic region of the Frasassi Gorge, Italy, were investigated to determine their microbial composition and their potential role in cave formation and ecosystem functioning. All biofilm samples examined had pH values <1.0. Scanning electron microscopy of the biofilms revealed the presence of various filaments and rods associated in large clusters with mineral crystals. Qualitative energy-dispersive x-ray analysis was used to determine that the crystals present on the cave walls, associated with the microbial biofilm, were composed of calcium and barium sulfate. Ribosomal RNA-based methods to determine the microbial composition of these biofilms revealed the presence of at least two strains of potential acidophilic, sulfur-oxidizing bacteria, belonging to the genera Thiobacillus and Sulfobacillus. An acid producing strain of Thiobacillus sp. also was obtained in pure culture. Stable isotope ratio analysis of carbon and nitrogen showed that the wall biofilms are isotopically light, suggesting that in situ chemoautotrophic activity plays an important role in this subsurface ecosystem

Speleogenesis of the Black Hills Maze Caves, South Dakota, USA, 2000, Palmer A. N. , Palmer M. V.
Caves of the Black Hills of South Dakota, USA, are located in the Madison Limestone of Mississippian (early Carboniferous) age in a zone of diagenetic breccias and late-Mississippian paleokarst. Most of the caves are extremely complex networks with multiple stratigraphically controlled storeys. Today they are essentially hydrologic relics. Their history is as complex as the caves themselves: (1) The earliest cave openings were formed by diagenetic processes, mainly by the dissolution and reduction of sulfates. Oxidation of hydrogen sulfide produced many small and rather isolated voids lined by brecciated bedrock. (2) Late Mississippian exposure produced caves, dolines, and surface fissures, which were later filled with basal Pennsylvanian (late Carboniferous) sands and clays of the Minnelusa Formation. (3) Deposition of sedimentary strata buried these early karst features to depths of at least two kilometers. During this time, voids that had not been entirely filled by Pennsylvanian sediment were lined by a thin layer of scalenohedral calcite, and later by quartz. (4) Uplift of the Black Hills at the end of the Cretaceous Period exposed the Madison Limestone once again, allowing rapid groundwater flow through it. The earlier caves and solution pockets were enlarged at this time. (5) A thick layer of rhombohedral calcite precipitated on the cave walls, probably as the result of stagnation of groundwater caused by late Tertiary aggradation, which blocked spring openings. (6) Both before and after the calcite wall crust was deposited, deep subaerial weathering produced boxwork, with veins of calcite that had replaced earlier sulfates, as well as thick accumulations of carbonate sediment. The Tertiary cave enlargement probably involved mixing of at least two of the following water sources: artesian flow from recharge along the carbonate outcrop area, diffuse recharge through the overlying sandstone, and rising thermal water. There is evidence for all three sources, but the relative importance of each is still uncertain.

Mn-Fe deposits in shallow cryptic marine environment: examples in northwestern Mediterranean submarine caves, 2001, Allouc J, Harmelin Jg,
Black coating of hard substrates by Mn and Fe oxides has long been reported from shallow, dark, submarine caves. However, these littoral metallic deposits have never been studied in detail, despite expected analogies with deep-sea polymetallic crusts. Submarine caves are characterized by darkness and low rates of exchanges with the open sea. Lack of primary production and confinement of inner water bodies result in marked oligotrophy and extremely reduced biomass, i.e. conditions close to those prevailing in deep-sea habitats. Field evidences suggested that the formation of Mn-Fe coatings was closely tied to these particular environmental conditions. The goal of this study was to examine the detailed features of Mn-Fe coatings from dark caves with different local conditions, and to try to identify the processes responsible for their deposition. Study sites and methods Three sublittoral, single-entrance, caves were sampled by scuba diving along the coasts of Provence (France, Mediterranean Sea) (fig. 1). The first site is a large karstic cave (Tremies Cave, 16 m depth at entrance floor, 60 m long; Marseille-Cassis area) with an ascending profile which results in a buffered thermal regime and markedly oligotrophic conditions due to warm water trapping in its upper part (fig. 1 and 2). Wall fragments were sampled at 30 m (medium confinement : zone B) and 60 in (strong confinement : zone C) from the cave entrance. The second site is a large tubular cavity open in conglomerate formations (3PP Cave, 15 m depth at entrance floor, 120 m long; La Ciotat) with a descending profile which results in relative permanence of winter temperatures within the inner parts, complex water circulation and presumed greater input of sedimented particles than in the preceding cave (fig.1 and 2). Wall samples were taken at 25 m, 70 in and 100 m from entrance. The third site is a small, horizontal, cave open in quartzite formations (Bagaud Cave, 7 in depth at entrance floor, about 10 m long; WNW of Port-Cros Island, bay of Hyeres). Sampling was performed on walls of a narrow corridor between an anterior room and a smaller inner room. A sporadic outflow of continental waters is located in the inner room. The samples were preserved in 50% ethylic alcohol or studied soon after their sampling. Before carbon coating and SEM examination, or microanalyses with SEM-associated spectrometers, they were treated in a 33% Chlorox solution and thereafter washed in demineralized water and dried. Micromorphology At low-medium magnification (<20,000), the aspect of coatings varies between caves and, especially, between inner-cave locations. All the described structures are made up of Mn and Fe oxides. In Tremies Cave, coatings of walls from zone B are composed of irregular erected constructions (height : 10s to 100s μm) formed by the aggregation of roughly ovoid primary concretions of about 10 μm (fig. 3). The surface of those primary concretions displays numerous lacunose to reticulate films (pores, about 0.5 μm in diameter, are often subrounded). Remnants of these films and organomorphic corpuscles occur also within the primary concretions (fig. 4). On younger substrates (broken wall exposed since 1970), primary concretions are poorly developed and no prominent construction is visible (fig. 5). In more confined conditions (zone C), the erected constructions of ancient coatings are smaller and less numerous than in zone B but are well individualized (fig. 6). In this zone: C, besides some remnants of lacunose to reticulate films (fig. 7), there is an appearance of filaments and ovoid corpuscles (height/width : 10-30/5-15 μm), which seem to be linked to filaments by a short stalk (fig. 8). In 3 PP Cave, at 25-70 m from entrance, wall coatings present porous heaps of primary concretions (fig. 9). The surface and the inside of the latter comprise remnants of lacunose to reticulate films that evoke those observed in Tremies Cave (fig. 10 and 11). On younger substrates (hard parts of sessile invertebrates), coatings are restricted to micrometric organomorphic corpuscles with some remnants of lacunose or fibrous films (fig. 12). At 100 in from the entrance, coatings are shaped by numerous erected constructions, more or less coalescing (fig. 13). Besides remnants of lacunose films, the primary concretions contain interlacing filaments (diameter : 0.2-0.3 μm) forming cords or veils (fig. 14). In Bagaud Cave, the primary concretions are aggregated in irregular heaps (fig. 15). Lacunose films are particularly frequent and tend to form three-dimensional mamillated structures that were not observed in the other caves (fig. 16). In particular, there is an appearance of tubular structures (fig. 17) and of numerous hemispheroidal structures (diameter : 4-5 μm) with an upper orifice (fig. 18 and 19). At higher magnification (20,000), whatever the cave and inner-cave location, the aspect of oxide deposits is rather smooth or, especially, microgranular (fig. 20). Mineral composition The composition of coatings is different between caves and according to their inner-cave location. In both large caves (Tremies and 3 PP), the Mn/Fe ratio increases with the distance from the cave entrance, i.e. when exchanges with the open sea diminish (fig. 21a). This trend is particularly clear in Tremies Cave, where the confinement gradient is strongly marked. Besides, the Mn/Fe ratio also seems to increase when films are present in the analysed volume (some cubic micrometers) (fig. 21b). In Bagaud Cave, the Mn/Fe ratio reaches high values despite the small size of this cave and its low confinement level. Discussion and conclusions SEM observations suggest that in each studied cave, the Mn-Fe coatings are biosedimentary deposits. Genesis of these deposits is assumed to result mainly from the replacement of biofilms (composed of cells and slime, i.e, of extracellular polymeric substance produced by microorganisms) generated by microbial populations colonizing the cave walls. Considering the darkness of the cave-locations, microbes consist mainly in bacteria, but fungi are probably responsible for the filaments and ovoids corpuscules (evoking sporocysts) occurring in innermost parts. Observations at different scales of the morphological features of oxide deposits reveal a structured organisation which varies along the strong environmental gradients (particularly the confinement level) that occur from the entrance to the innermost parts : erected constructions made up of primary concretions become more and more defined and acquire a pseudo-columnar shape. The aspect of biofilms appears to be controlled by the same environmental parameters. In open or relatively open environments, they frequently show a three-dimensional development (with frequent skullcape-like shapes), while in more confined conditions they exhibit a planar layout. These changes reflect either the adaptation of the slime-producing bacteria to the local trophic resources (correlated to the rate of exchange with the open sea) and water movements, or spatial replacement of taxa. It is assumed that slime (mainly composed of water and exopolysaccharides) induces a local increase of the concentration in dissolved Mn and acts as an ion exchange resin that allows the retention of Mn on the functional groups of EPS. These conditions promote the nucleation of Mn oxide crystallites in the slime. Then. the anionic character of Mn oxides in seawater, and their capacity to catalyse the oxydation of Mn2 to Mn4, allow the process to go on without any other biological intervention; thus, the process of crystal growth becomes possible. In caves where Mn is only supplied by seawater (Tremies and 3 PP), the average value of the Mn/Fe ratio of coatings is negatively correlated to the local availability of nutrients. This trend is probably linked to changes in the selectivity of slimes towards the processes of retention of cations, because this ratio is clearly influenced by the occurrence of biofilms. However, independently from trophic resources, the Mn/Fe ratio can be notably increased when additional Mn is provided by the seeping or flowing of continental waters (Bagaud Cave)

Geomicrobiology of caves: A review, 2001, Northup D. E. , Lavoie K. H. ,
In this article, we provide a review of geomicrobiological interactions in caves, which are nutrient-limited environments containing a variety of redox interfaces. Interactions of cave microorganisms and mineral environments lead to the dissolution of, or precipitation on, host rock and speleothems (secondary mineral formations). Metabolic processes of sulfur-, iron-, and manganese-oxidizing bacteria can generate considerable acidity, dissolving cave walls and formations. Examples of possible microbially influenced corrosion include corrosion residues (e.g., Lechuguilla and Spider caves, New Mexico, USA), moonmilk from a number of caves (e.g., Spider Cave, New Mexico, and caves in the Italian Alps), and sulfuric acid speleogenesis and cave enlargement (e.g., Movile Cave, Romania, and Cueva de Villa Luz, Mexico). Precipitation processes in caves, as in surface environments, occur through active or passive processes. In caves, microbially induced mineralization is documented in the formation of carbonates, moonmilk, silicates, clays, iron and manganese oxides, sulfur, and saltpeter at scales ranging from the microscopic to landscape biokarst. Suggestions for future research are given to encourage a move from descriptive, qualitative studies to more experimental studies

On the genetic conditions of black manganese deposits from two caves of Eastern Serbia., 2001, Ljubojevic V. , Pafevski A. , Calicljubojevic J.
Portions of cave passages often have a black colour due to manganese deposits that occur as coatings on cave walls and ceilings, on clastic sediments, as well as on speleothems. On samples from the cave Buronov Ponor chemical analysis, infrared spectroscopy. X-ray diffraction and DTA analysis confirmed the presence of birnessite. In cave Cerjanska Pecina, the presence of manganese compounds in the black coating has been confirmed by chemical tests. In both caves it has been noted that cave passages with black coating have a distinct morphology. They are highly weathered showing an abundance of sharp prolusions, potholes in the streambed and scallops. The paper studies these occurrences and the possible link between the manganese deposition, hydrology and morphology of the passages and petrologic composition. Although this link was not identified, some interesting questions regarding manganese deposition arose. It remains unclear why manganese deposition is limited only to a certain part of cave Cerjanska Pecina, and what caused the cyclicity in manganese deposition in the cave Buronov ponor. manganese deposits, chemical analysis, speleomorphology

The hypogenic caves: a powerful tool for the study of seeps and their environmental effects, 2002, Forti P, Galdenzi S, Sarbu Sm,
Research performed in caves has shown the existence of significant effects of gas seeps, especially CO2 and H2S, within subterranean voids. Carbon dioxide causes important corrosive effects and creates characteristic morphologies (e.g., bell-shaped domes, bubble's trails), but is not involved in the deposition of specific cave minerals. On the other hand, in carbonate environments, hydrogen sulfide when oxidized in the shallow sections of the aquifer generates important corrosion effects and is also responsible for the deposition of specific minerals of which gypsum is the most common.Studies performed in the last few years have shown that H2S seeps in caves are associated with rich and diverse biological communities, consisting of large numbers of endemic species. Stable isotope studies (carbon and nitrogen) have demonstrated that these hypogean ecosystems are entirely based on in situ production of food by chemoautotrophic microorganisms using energy resulting from the oxidation of H2S.Although located only 20 m under the surface, Movile Cave does not receive meteoric waters due to a layer of impermeable clays and loess that covers the Miocene limestone in which the cave is developed. In the Frasassi caves, where certain amounts of meteoric water seep into the limestone, the subterranean ecosystems are still isolated from the surface. As the deep sulfidic waters mix with the oxigenated meteoric waters, sulfuric acid limestone corrosion is accelerated resulting in widespread deposition of gypsum onto the cave walls.Both these caves have raised a lot of interest for biological investigations regarding the chemoautotrophically based ecosystems, demonstrating the possibility of performing such studies in environments that are easily accessible and easy to monitor compared to the deep-sea environments where the first gas seeps were discovered

Origin of fine-grained carbonate clasts in cave sediments, 2002, Zupan Hajna, Nadja

In many samples of cave clastic sediments the high amount of carbonate clasts is significant. It was found out that their origin is usually in soft white zones of weathered carbonate rock on cave walls. Weathered zones of limestone or dolomite form on the cave walls when the selective corrosive is going on. Incomplete dissolution prepares the carbonate rock for the mechanical erosion and transport of its particles. Where the weathered carbonate rock is in contact with water, both flowing and dripping, it may tear off the particles resulting from selective corrosion. Water carries them along cave passages and when its transporting power decreases, particles accumulate in the form of a fine-grained autochthonous carbonate deposit, in size of clay, silt or fine sand.

On feasibility of condensation corrosion in caves (Comment to the paper: ''Hypogenic caves in Provence (France): Specific features and sediments'' by Ph. Audra, J.Y. Bigot and L. Mocochain), 2003, Dreybrodt, W.

In Fig. 6 of this paper the authors suggest how condensation corrosion could shape ceiling cupolas. Hot water containing high concentration of carbon dioxide rises to a lake filling the lower part of the cave room. Degassing of CO2 creates a CO2-containing atmosphere, which is heated by the warmer water below and becomes saturated with vapor, which condenses to the cooler wall of the cave, dissolves limestone and flows back to the lake.
If this process would continue in time it would be perfect to shape large cupolas. However, it does not because condensation stops when the temperature of the cave walls approaches that of the heated air. The reason is that condensation of water at the cave wall releases heat of condensation of 2.45 kJoule/g. This corresponds to an energy flux of 28 Watt/square-meter if a film of 1 mm depth would condensate to the wall in one day. In addition there is also a flux of heat from the warm air to the cave wall. Since the thermal conductivity of limestone (1.3 Watt/m°K) and its thermal diffusivity (5.6 x 10-7 m2/s) are low this heat cannot be rapidly transported into the bedrock, and consequently the temperature of the cave wall rises. Therefore the amount of condensation is reduced. 

One further comment should be given. There have been attempts to measure the effect of condensation corrosion by suspending gypsum plates freely in the air and determining weight loss after a defined time. For the reasons stated above the heat of condensation and the heat flux from the air raise the temperature of such samples much quicker than that of the cave walls. Reliable measurements can only be performed when such samples are fixed to the cave walls by using a high thermal conductivity glue.

A further suggestion to prove condensed water on cave walls is to take samples and analyse them for Ca-concentration and 13 carbon isotopic ratio. Since CO2 comes from the atmosphere exclusively should be below or close to zero, and Ca-concentration should be about 0.6 mmol/liter, when the pCO2 of the cave atmosphere is atmospheric.

Geochemistry of capillary seepage in Mammoth Cave., 2003, Palmer A. N. , Palme M. V.

Low-velocity capillary seepage in the vadose zone is responsible for a variety of geochemical processes in Mammoth Cave . Water that infiltrates through the cap-rock of detrital sandstone and shale is isolated from the high-CO 2 of the soil before it encounters the underlying carbonate rocks, so that carbonate dissolution in narrow fissures around the cave takes place under nearly closed conditions with respect to CO 2 . As a result, the equilibrium P CO2 of the capillary water decreases to nearly zero and the pH can rise to more than 9.0. When the water emerges into the cave it rapidly absorbs CO 2 from the cave air and becomes highly aggressive toward carbonate rocks. Where discrete trickles exit from fissures, deep irregular rills are formed. Where the flow is more diffuse, the cave walls are weathered to a chalky white by partial dissolution and recrystallization of the carbonate rock. If the water has acquired sulfate from oxidation of pyrite or dissolution of residual gypsum within the bedrock, the SO 4 = /CO 3 = ratio of the water rises sharply at the cave walls, promoting the replacement of carbonate bedrock by gypsum. The pH decrease caused by the uptake of CO 2 enables silica to precipitate in small amounts in the weathering rind. Direct measurement of capillary water chemistry is difficult because of the small quantity and inaccessibility of the water involved, but it can be reliably inferred from the geochemical setting and the effects upon the cave.

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