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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 alluvial is pertaining to or composed of alluvium or deposited by a stream or running water [6]. also applies to material lining the floor of a cave and deposits at the mouth of a spring.?

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

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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
See all featured articles from other geoscience journals

Search in KarstBase

Your search for products (Keyword) returned 66 results for the whole karstbase:
Showing 16 to 30 of 66
Finding minimal herbicide concentrations in ground water? Try Looking for their degradates, 2000, Kolpin D. W. , Thurman E. M. , Linhart S. M. ,
Extensive research has been conducted regarding the occurrence of herbicides in the hydrologic system, their fate, and their effects on human health and the environment. Few studies, however, have considered herbicide transformation products (degradates). In this study of Iowa ground water, herbicide degradates were frequently detected. In fact, herbicide degradates were eight of the 10 most frequently detected compounds. Furthermore, a majority of a herbicide's measured concentration was in the form of its degradates - ranging from 55 to over 99%. The herbicide detection frequencies and concentrations varied significantly among the major aquifer types sampled. These differences, however, were much more pronounced when herbicide degradates were included. Aquifer types presumed to have the most rapid recharge rates (alluvial and bedrock/karst region aquifers) were those most likely to contain detectable concentrations of herbicide compounds. Two indirect estimates of ground-water age (depth of well completion and dissolved-oxygen concentration) were used to separate the sampled wells into general vulnerability classes (low, intermediate, and high). The results show that the herbicide detection frequencies and concentrations varied significantly among the vulnerability classes regardless of whether or not herbicide degradates were considered. Nevertheless, when herbicide degradates were included, the frequency of herbicide compound detection within the highest vulnerability class approached 90%, and the median total herbicide residue concentration increased over an order of magnitude, relative to the parent compounds alone, to 2 mu g/l. The results from this study demonstrate that obtaining data on herbicide degradates is critical for understanding the fate of herbicides in the hydrologic system. Furthermore, the prevalence of herbicide degradates documented in this study suggests that to accurately determine the overall effect on human health and the environment of a specific herbicide its degradates should also be considered. (C) 2000 Elsevier Science B.V. All rights reserved

Occurrence of cyanazine compounds in groundwater: Degradates more prevalent than the parent compound, 2001, Kolpin D. W. , Thurman E. M. , Linhart S. M. ,
A recently developed analytical method using liquid chromatography/mass spectrometry was used to investigate the occurrence of cyanazine and its degradates cyanazine acid (CAC), cyanazine amide (CAM), deethylcyanazine (DEC), and deethylcyanazine acid (DCAC) in groundwater. This research represents some of the earliest data on the occurrence of cyanazine degradates in groundwater. Although cyanazine was infrequently detected in the 64 wells across Iowa sampled in 1999, cyanazine degradates were commonly found during this study. The most frequently detected cyanazine compound was DCAC (32.8%) followed by CAC (29.7%), CAM (17.2%), DEC (3.1%), and cyanazine (3.1%). The frequency of detection for cyanazine or one or more of its degradates (CYTOT) was more than 12-fold over that of cyanazine alone (39.1% for CYTOT Versus 3.1% for cyanazine). Of the total measured concentration of cyanazine, only 0.2% was derived from its parent compound-with DCAC (74.1%) and CAC (18.4%) comprising 92.5% of this total. Thus, although DCAC and CAC had similar frequencies of detection, DCAC was generally present in higher concentrations. No concentrations of cyanazine compounds for this study exceeded water-quality criteria for the protection of human health. Only cyanazine, however, has such a criteria established. Nevertheless, because these cyanazine degradates are still chlorinated, they may have similar toxicity as their parent compound-similar to what has been found with the chlorinated degradates of atrazine. Thus, the results of this study documented that data on the degradates for cyanazine are critical for understanding its fate and transport in the hydrologic system. Furthermore, the prevalence of the chlorinated degradates of cyanazine found in groundwater suggests that to accurately determine the overall effect on human health and the environment from cyanazine its degradates should also be considered. In addition, because CYTOT was found in 57.6% of the samples collected from alluvia[ aquifers, about 2-5 times more frequently than the other major aquifer types (glacial drift, bedrock/karst, bedrock/nonkarst) under investigation, this finding has long-term implications for the occurrence of CYTOT in streams. It is anticipated that low-level concentrations of CYTOT will continue to be detected in streams for years after the use of cyanazine has terminated (scheduled for the year 2000 in the United States), primarily through its movement from groundwater into streams during base-flow conditions

Chemical and physical controls on waters discharged from abandoned underground coal mines, 2001, Lopez D. L. , Stoertz M. W. ,
Abandoned up-dip drift mines in high-sulphur coal are a major source of acid mine drainage (AMD) in Appalachia. Studies of mines in the Monday Creek watershed of southeastern Ohio show that mines are recharged by surface runoff into subsidence features that dilate the natural stress-relief fracture system. The direct connection between the ground surface and the mines leads to a rapid response in the hydrograph, with a one- to four-day lag between precipitation and corresponding peak mine discharge. Subsidence occurs in topographic depressions where overburden is presumably relatively thin. Subsidence features drain 20-36% of the surface area. Unsaturated storage appears to be volumetrically insignificant, so that far more recharge occurs than the 5% often assumed for this region. Mine storage can change rapidly due to subsidence recharge. Hydrologically, mines with subsidence features behave like karst systems, with meteoric quickflow' representing more than 50% of the total flow. Mine discharge concentrations are relatively uniform through time, suggesting either equilibrium controls on chemistry or drainage of a well-mixed pool, or both. Evidence of dilution by high flows is slight. The first high flows after a baseflow period show only a slight increase in concentrations, attributed to flushing of stored reaction products. Loadings (concentrations x flow) depend on volumetric discharge and as a consequence are highly variable. The Eh/pH environment in up-dip drift mines indicates that mine waters are in contact with the atmosphere at least part of the time, unlike a true groundwater. Iron buffering partly controls pH, which clusters around values of 3.6-5.0

Partitioning of Sr2 and Mg2 into calcite under karst-analogue experimental conditions, 2001, Huang Yiming, Fairchild Ian J. ,
There is a paucity of experimental data on calcite precipitation from waters at low ionic strength and low ratios of Mg/Ca and Sr/Ca, using controlled and constant precipitation rates. Such data are particularly needed for studies of speleothem geochemistry in relation to palaeoclimates.We carried out a series of experiments using a karst-analogue set-up in a chamber of constant temperature and 100% humidity. A steady flow of NaHCO3 and CaCl2 solutions at PCO2 around 10-3.2 were mixed just before passage through a tube (analogous to a soda-straw stalactite) and allowed to drip onto a surface, analogous to a stalagmite. Growth rates were comparable with linear extension rates of natural speleothems.Analytical spots gave reproducible analyses in later analytical cycles after ablation of surface calcite with Na and Mg contamination. Different crystals from the same experiment tended to show positive covariation of Na and Mg with negative covariation with Sr. This may be due to the presence of growth hillocks with vicinal faces with differential partitioning behaviour.The result for the partition coefficient for Mg (DMg) at 25[deg]C is 0.031 0.004, which is quantitatively in good agreement with the trends of previous workers. At 15[deg]C, the result is 0.019 0.003. The temperature dependency is higher than experimental data on seawater-analogue solutions, but lower than a previous estimate based on a comparison of speleothem chemistry with single water analyses.Data for DSr are mainly in the range of 0.057 to 0.078, with a possible weak dependency on growth rate, consistent with previous experimental work. Absolute values are higher than studies in Mg-free saline solutions, which is attributed mainly to salinity effects. Values of DSr are nevertheless somewhat lower than in natural caves, which may relate to crystal growth factors.Mg partition coefficient values should allow robust determination of solution Mg/Ca compositions in enclosed caves, which are at constant temperature on the decadal timescale. The inferred sensitivity of DSr to growth rate factors implies that Sr values should be interpreted more cautiously. Muted changes could relate entirely to growth rate variations, whereas changes of large magnitude imply a control by solution composition. The absence of local (tens of micron scale) antipathetic variations in Sr and Mg in studied natural speleothems, implies that intracrystalline zoning phenomena, if present, are on a finer scale in those natural materials compared with experimental products

Palaeo-mixing zone karst features from Palaeocene carbonates of north Spain: criteria for recognizing a potentially widespread but rarely documented diagenetic system, 2001, Bacetaa J. I. , Wrightb V. P. , Pujalte V.

Marine-meteoric mixing zone dissolution effects are a major feature of present day karst systems in carbonate platforms,yet are rarely reported in the geological record. An example is described from the upper Danian platform limestones of the Alava province,in  the western Pyrenees,north Spain. This consists of several narrow zones with sponge-like porosity analogous to the "Swiss-cheese" features found in present day mixing  zones. These zones are stained by Fe-oxides and overlie limestones which are irregularly  dolomitized  and contain disseminated pyrite. These high-porosity  zones are interpreted as having developed in marine mixing zones where mixing corrosion and microbially  mediated processes increased dissolution. If collapsed,ancient mixing zones could be misinterpreted as "terra-rossa" palaeosols. The main criteria to identify them as mixing zone products are their occurrence below a palaeo-meteoric phreatic zone,their association with stratified oxic and anoxic redox zones and petrographic evidence for highly variable calcite saturation states.


Palaeo-mixing zone karst features from Palaeocene carbonates of north Spain: criteria for recognizing a potentially widespread but rarely documented diagenetic system , 2001, Baceta J. I. , Wrightb V. P. , Pujaltec V.

Marine-meteoric mixing zone dissolution effects are a major feature of present day karst systems in carbonate platforms,yet are rarely reported in the geological record. An example is described from the upper Danian platform limestones of the Alava province,in the western Pyrenees,north Spain. This consists of several narrow zones with sponge-like porosity analogous to the "Swiss-cheese" features found in present day mixing zones. These zones are stained by Fe-oxides and overlie limestones which are irregularly dolomitized and contain disseminated pyrite. These high-porosity zones are interpreted as having developed in marine mixing zones where mixing corrosion and microbially mediated processes increased dissolution. If collapsed,ancient mixing zones could be misinterpreted as "terra-rossa" palaeosols. The main criteria to identify them as mixing zone products are their occurrence below a palaeo-meteoric phreatic zone,their association with stratified oxic and anoxic redox zones and petrographic evidence for highly variable calcite saturation states


Existence of karsts into silicated non-carbonated crystalline rocks in Sahelian and Equatorial Africa, hydrogeological implications, 2002, Willems Luc, Pouclet Andre, Vicat Jean Paul,
Various cavities studied in western Niger and South Cameroon show the existence of important karstic phenomena into metagabbros and gneisses. These large-sized caves resulted from generalized dissolution of silicate formations in spite of their low solubility. Karstification is produced by deep hydrous transfer along lithological discontinuities and fracture net works. The existence of such caves has major implications in geomorphology, under either Sahelian and Equatorial climate, and in hydrogeology and water supply, particularly in the Sahel area. Introduction. - Since a few decades, several karst-like morphologies are described in non-carbonated rocks (sandstones, quartzites, schistes, gneisses...) [Wray, 1997 ; Vicat and Willems, 1998 ; Willems, 2000]. The cave of Guessedoundou in West Niger seems to be due to a large dissolution of metagabbros. The cave of Mfoula, South Cameroon, attests for the same process in gneisses. This forms proof that big holes may exist deeper in the substratum even of non-carbonated silicate rocks. Their size and number could mainly influence the landscape and the hydrogeology, especially in the Sahelian areas. Guessedoundou, a cave into metagabbros in West Niger. - The site of Guessedoundou is located 70 km south-west of Niamey (fig. 1). The cave is opened at the top of a small hill, inside in NNE-SSW elongated pit (fig. 2 ; pl. I A). The hole, 3 to 4 m deep and 20 m large, has vertical walls and contains numerous sub-metric angular blocks. A cave, a few meters deep, comes out the south wall. Bedrocks consist of metagabbros of the Makalondi greenstone belt, a belt of the Palaeoproterozoic Birimian Formations of the West Africa craton [Pouclet et al., 1990]. The rock has a common granular texture with plagioclases, partly converted in albite and clinozoisite, and pyroxenes pseudomorphosed in actinote and chlorite. It is rather fairly altered. Chemical composition is mafic and poorly alkaline (tabl. I). A weak E-W schistosity generated with the epizonal thermometamorphism. The site depression was created along a N010o shear zone where rocks suffered important fracturation and fluid transfers, as shown by its silification and ferruginisation. The absence of human activity traces and the disposition of the angular blocks attest that the pit is natural and was due to the collapse of the roof of a vast cavity whose current cave is only the residual prolongation. To the vertical walls of the depression and at the cave entry, pluridecimetric hemispheric hollows are observed (pl. I B). Smooth morphology and position of these hollows sheltered within the depression dismiss the assumptions of formation by mechanical erosion. In return, these features are typical shape of dissolution processes observed into limestone karstic caves. That kind of process must be invoked to explain the opening of the Guessedoundou cave, in the total lack of desagregation materials. Dissolution of metagabbro occurred during hydrous transfer, which was probably guided by numerous fractures of the shear zone. Additional observations have been done in the Sirba Valley, where similar metabasite rocks constitute the substratum, with sudden sinking of doline-like depressions and evidence of deep cavities by core logging [Willems et al., 1993, 1996]. It is concluded that karstic phenomena may exist even in silica-aluminous rocks of crystalline terrains, such as the greenstones of a Precambrian craton. Mfoula a cave into gneisses in South Cameroon. - The cave of Mfoula is located 80 km north-east of Yaounde (fig. 3). It is the second largest cave of Cameroon, more than 5,000 m3, with a large opening in the lower flank of a deep valley (pl. I C). The cavity is about 60 m long, 30 m large and 5 to 12 m high (fig. 4; pl. I D). It is hollowed in orthogneisses belonging to the Pan-African Yaounde nappe. Rocks exhibit subhorizontal foliation in two superposed lithological facies: the lower part is made of amphibole- and garnet-bearing layered gneisses, and the upper part, of more massive granulitic gneisses. Average composition is silico-aluminous and moderately alkaline (tabl. I). The cave is made of different chambers separated by sub-cylindrical pillars. The ceiling of the main chamber, 6 m in diameter, is dome-shaped with a smooth surface (D, fig. 4). The walls have also a smooth aspect decorated with many hemispherical hollows. The floor is flat according to the rock foliation. They are very few rock debris and detrital fragments and no traces of mechanical erosion and transport. The general inner morphology is amazingly similar to that of a limestone cave. The only way to generate such a cavity is to dissolve the rock by water transfer. To test the effect of the dissolution process, we analysed a clayey residual sampled in an horizontal fracture of the floor (tabl. I). Alteration begins by plagioclases in producing clay minerals and in disagregating the rock. However, there is no more clay and sand material. That means all the silicate minerals must have been eliminated. Dissolution of silicates is a known process in sandstone and quartzite caves. It may work as well in gneisses. To fasten the chemical action, we may consider an additional microbial chemolitotrophe activity. The activity of bacteria colonies is known in various rocks and depths, mainly in the aquifer [Sinclair and Ghiorse, 1989 ; Stevens and McKinley, 1995]. The formation of the Mfoula cave is summarized as follow (fig. 5). Meteoric water is drained down along sub-vertical fractures and then along horizontal discontinuities of the foliation, particularly in case of lithological variations. Chemical and biological dissolution is working. Lateral transfers linked to the aquifer oscillations caused widening of the caves. Dissolved products are transported by the vertical drains. Regressive erosion of the valley, linked to the epeirogenic upwelling due to the volcano-tectonic activity of the Cameroon Line, makes the cavities come into sight at the valley flanks. Discussion and conclusion. - The two examples of the Guessedoundou and Mfoula caves evidence the reality of the karsts in non-carbonated silicated rocks. The karst term is used to design >> any features of the classical karst morphology (caves, dolines, lapies...) where dissolution plays the main genetical action >> [Willems, 2000]. Our observations indicate that (i) the karst genesis may have occurred into any kind of rocks, and (ii) the cave formation is not directly dependent of the present climate. These facts have major consequences to hydrogeological investigations, especially for water supply in Sahelian and sub-desertic countries. Some measurements of water transfer speed across either sedimentary pelitic strata of the Continental terminal or igneous rocks of the substratum in West Niger [Esteves and Lenoir, 1996 ; Ousmane et al., 1984] proved that supplying of aquifers in these silico-aluminous rocks may be as fast as in a karstic limestone. That means the West Niger substratum is highly invaded by a karstic net and may hidden a lot of discontinuous aquifers. The existence of this karst system can be easily shown by morphological observations, the same that are done in karstic limestone regions (abnormally suspended dry valleys, collapses, dolines...). Clearly, this must be the guide for any search of water, even in desertic areas where limestones are absent

Microgranulometric approach to a chalk karst, western Paris Basin, France, 2002, Lacroix M. , Rodet J. , Wang H. Q. , Laignel B. , Dupont J. P. ,
By definition, karst is the result of dissolution, and if the rock is not completely soluble, residues will remain ('acquired' particles). These insoluble residues provide a history of karstic activity and can be found in the outflows after a possible storage period in the endokarst. A direct connection, even if temporary, between the endokarst and the surface is reflected by the contribution of particles, which are referred to as 'inherited'. We have studied the chalk karsts of Haut Normandie by comparing microgranulometric spectra of suspended matter (SM), in subterranean waters and in solutions of the main surface formations (Clay-with-Flints Complex (CFC) and loess) and the Chalk dissolution products of all local stratigraphic levels. Based on these microgranulometric spectra, we propose a conceptual model for processes occurring in chalk karsts and a classification scheme for karstified systems according to how such systems deal with particles. In a 'closed' karst, the suspended matter tends to come from the Chalk itself, while in the case of an 'open' karst, the majority of suspended particles comes from surface formations. This notion of 'openness' differs from the currently used categorization into allogenic and autogenic systems, which depends upon an impermeable cover concentrating the infiltration. (C) 2002 Elsevier Science B.V All rights reserved

Sequence Stratigraphy of the Neoproterozoic Infra Krol Formation and Krol Group, Lesser Himalaya, India, 2002, Jiang Ganqing, Christieblick Nicholas, Kaufman Alan J. , Banerjee Dhiraj M. , Rai Vibhuti,
A sequence stratigraphic study of terrigenous and carbonate rocks of the Infra Krol Formation and Krol Group in the Lesser Himalaya fold and thrust belt of northern India was undertaken as part of a broader investigation of the significance of carbon isotope data in Neoproterozoic successions. Eight regional stratigraphic discontinuities were traced over a distance of nearly 300 km, and interpretations were anchored in a series of local studies involving the mapping of key beds and the measurement of closely spaced sections. Three of the regional surfaces are interpreted as sequence boundaries on the basis of (1) locally developed incised valleys < 60 m deep; (2) paleokarstic depressions with < 50 m of mappable relief; (3) subaerial dissolution and weathering products (breccias and calcrete) filling vertical fissures, dikes, cavities, and shallow depressions in underlying carbonate rocks; and (4) small-scale evidence for subaerial exposure at an erosion surface. The remaining five discontinuities are regional flooding surfaces identified on the basis of either facies changes with an abrupt upward deepening across the surface or transitions in facies stacking patterns, typically from forestepping to backstepping. A glacio-eustatic origin is permitted, although not required, for the three sequence boundaries, but no evidence has been found for marked lowering of sea level at other horizons. A mismatch between the stratigraphic location of sequence boundaries and carbon isotope minima suggests that local diagenetic alteration or oceanographic phenomena unrelated to glaciation may be in part responsible for observed isotopic variation, and that small ice sheets may have existed during apparently nonglacial times without producing either cap carbonates or negative carbon isotope excursions

Melting of the glacier base during a small-volume subglacial rhyolite eruption: evidence from Blahnukur, Iceland, 2002, Tuffen H. , Pinkerton H. , Mcgarvie D. W. , Gilbert J. S. ,
Although observations of recent volcanic eruptions beneath Vatnajokull, Iceland have improved the understanding of ice deformation and meltwater drainage, little is known about the processes that Occur at the glacier base. We present observations of the products of a small-volume, effusive subglacial rhyolite eruption at Blahnukur. Torfajokull, Iceland. Lava bodies, typically 7 m long, have unusual conical morphologies and columnar joint orientations that suggest emplacement within cavities melted into the base of a glacier. Cavities appear to have been steep-walled and randomly distributed. These features can be explained by a simple model of conductive heat loss during the ascent of a lava body to the glacier base. The released heat melts a cavity in the overlying ice. The development of vapour-escape pipes in the waterlogged, permeable breccias surrounding the lava allows rapid heat transfer between lava and ice. The formed meltwater percolates into the breccias, recharging the cooling system and leaving a steam-filled cavity. The slow ascent rates of intrusive rhyolitic magma bodies provide ample time for a cavity to be melted in the ice above, even during the final 10 m of ascent to the glacier base. An equilibrium Cavity Size is Calculated at which melting, is balanced by creep closure, This is dependent upon the heat input and the difference between glaciostatic and cavity pressure. The cavity sizes inferred from Blahnukur are consistent with a pressure differential of 2-4 MPa, suggesting that the ice was at least 200 m thick. This is consistent with the volcanic stratigraphy, which indicates that the ice exceeded 350 in in thickness, Although this is the first time that a subglacial cavity system of this type has been reconstructed from an ancient volcanic sequence. it shares many characteristics with the modem fim cave system formed by fumarolic melting within the summit crater of Mount Rainier. Washington, At both localities, it appears that localised heating at the glacier base has resulted in heterogeneous melting patterns. Despite the different theological properties of ice and fim, similar patterns of cavity roof deformation are inferred. The development of low-pressure subglacial cavities in regions of high heat nux may influence the trajectory of rising magma, with manifold implications for eruptive mechanisms and resultant subglacial volcanic landforms. (C) 2002 Elsevier Science B.V. All rights reserved

Lower Miocene gypsum palaeokarst in the Madrid Basin (central Spain): dissolution diagenesis, morphological relics and karst end-products, 2002, Rodriguezaranda J. P. , Calvo J. P. , Sanzmontero M. E. ,
The Miocene sedimentary record of the Madrid Basin displays several examples of palaeokarstic surfaces sculpted within evaporite formations. One of these palaeokarstic surfaces represents the boundary between two main lithostratigraphic units, the Miocene Lower and Intermediate units of the Madrid Basin. The palaeokarst formed in lacustrine gypsum deposits of Aragonian age and corresponds to a surface palaeokarst (epikarst), further buried by terrigenous deposits of the overlying unit. Karst features are recognized up to 5.5 m beneath the gypsum surface. Exokarst and endokarst zones are distinguished by the spatial distribution of solution features, i.e. karren, dolines, pits, conduits and caves, and collapse breccias, sedimentary fills and alteration of the original gypsum across the karst profiles. The development of the gypsum palaeokarst began after drying out of a saline lake basin, as supported by recognition of root tubes, later converted to cylindrical and funnel-shaped pits, at the top of the karstic profiles. The existence of a shallow water table along with low hydraulic gradients was the main factor controlling the karst evolution, and explains the limited depth reached by both exokarst and endokarst features. Synsedimentary fill of the karst system by roughly laminated to massive clay mudstone with subordinate carbonate and clastic gypsum reflects a punctuated sedimentation regime probably related to episodic heavy rainfalls typical of arid to semi-arid climates. Duration of karstification is of the order of several thousands of years, which is consistent with previous statements that gypsum karstification can develop rapidly over geologically short time periods

MEDICAL SURVEY OF THE STAFF WORKING IN THE ŠKOCJAN CAVES, SLOVENIA , 2002, Debevec Gerjevič, Vanja

The cave microclimate is distinguished by many parameters that could underlie some physiological changes in human body when exposed for an extended period of time. Beside temperature, air-flow, the absence of sunlight and humidity, which vary according to the location and structure of the underground space, radon radiation is present as well. Park Škocjanske jame, Slovenia, has been performing a regular and continuous monitoring of radon and its daughter products for about five years now. All measurements are done by the Institute for Occupational Safety, Ljubljana. The accurate evidence of time spent in the cave is kept for every member of the staff. This enables us to combine the data with radon concentration and determine the maximum dose of radiation that one has received during one year working period. According to national regulation and law, stated by National Health Inspector and Ministry of Health, a regular medical survey has been established. Detailed medical exams are performed each year or less frequently in order to prevent health problems. Blood tests enable us to observe radiation impact. In the following work a short overview of microclimates impacts will be presented as health and risk factors.


Karst processes from the beginning to the end: How can they be dated?, 2003, Bosk, B

Determining the beginning and the end of the life of a karst system is a substantial problem. In contrast to most of living systems development of a karst system can be „frozen“ and then rejuvenated several times (polycyclic and polygenetic nature). The principal problems may include precise definition of the beginning of karstification (e.g. inception in speleogenesis) and the manner of preservation of the products of karstification. Karst evolution is particularly dependent upon the time available for process evolution and on the geographical and geological conditions of the exposure of the rock. The longer the time, the higher the hydraulic gradient
and the larger the amount of solvent water entering the karst system, the more evolved is the karst. In general, stratigraphic discontinuities, i.e. intervals of nondeposition (disconformities and unconformities), directly influence the intensity and extent of karstification. The higher the order of discontinuity under study, the greater will be the problems of dating processes and events. The order of unconformities influences the stratigraphy of the karst through the amount of time available for subaerial processes to operate. The end of karstification can also be viewed from various perspectives. The final end occurs at the moment when the host
rock together with its karst phenomena is completely eroded/denuded. In such cases, nothing remains to be dated. Karst forms of individual evolution stages (cycles) can also be destroyed by erosion, denudation and abrasion without the necessity of the destruction of the whole sequence of karst rocks. Temporary and/or final interruption of the karstification process can be caused by the fossilisation of karst due to loss of its hydrological function. Such fossilisation can be caused by metamorphism, mineralisation,
marine transgressions, burial by continental deposits or volcanic products, tectonic movements, climatic change etc. Known karst records for the 1st and 2nd orders of stratigraphic discontinuity cover only from 5 to 60 % of geological time. The shorter the time available for karstification, the greater is the likelihood that karst phenomena will be preserved in the stratigraphic record. While products of short-lived karstification on shallow carbonate platforms can be preserved by deposition during the immediately succeeding sea-level rise, products of more pronounced karstification can be destroyed by a number of different geomorphic
processes. The longer the duration of subaerial exposure, the more complex are those geomorphic agents.
Owing to the fact that unmetamorphosed or only slightly metamorphosed karst rocks containing karst and caves have occurred since Archean, we can apply a wide range of geochronologic methods. Most established dating methods can be utilised for direct and/or indirect dating of karst and paleokarst. The karst/paleokarst fills are very varied in composition, including a wide range of clastic and chemogenic sediments, products of surface and subsurface volcanism (lava, volcaniclastic materials, tephra), and deepseated
processes (hydrothermal activity, etc). Stages of evolution can also be based on dating correlated sediments that do not fill karst voids directly. The application of individual dating methods depends on their time ranges: the older the subject of study, the more limited is the choice of method. Karst and cave fills are relatively special kinds of geologic materials. The karst environment favours both the preservation of paleontological remains and their destruction. On one hand, karst is well known for its richness of paleontological sites, on the other hand most cave fills are complete sterile, which is true especially for the inner-cave facies. Another
problematic feature of karst records is the reactivation of processes, which can degrade a record by mixing karst fills of different ages.


Nonsulfide Zinc Mineralization in Europe: An Overview, 2003, Boni M, Large D,
A number of occurrences and deposits of nonsulfide zinc ores in Europe were the historical basis for the development of the zinc mining and smelting industry. The principal occurrences in Silesia (Poland), Sardinia (Italy), and northern Spain are described. These deposits are products of the supergene oxidation of primary carbonate-hosted sulfide minerals during the complex interplay of tectonic uplift, karst development, changes in the level of the water table, and weathering. The nonsulfide zinc mineral deposits in the Irish Midlands may represent an example of surface oxidation of primary sulfide mineral deposits, redeposition, and preservation under glacial till. The willemite-dominated mineralization at La Calamine, Belgium, may be related to paleoweathering or be of possible hydrothermal origin, similar to other willemite deposits in the world

Evolution of the gypsum karst of Sorbas (SE Spain), 2003, Calaforra Jm, Pulidobosch A,
The gypsum karst of Sorbas is developed within Messinian gypsum characterized by an interbedded sequence of selenitic gypsum beds and marls. This geological configuration has led to the development of an interstratal karst in which galleries have developed in the marl levels, but not in the gypsum ones. Up to six cave passage levels have been detected in the gypsum caves following stratification planes between the impervious intercalated marls and the pervious gypsum strata. The explanation for this lies in the hydrogeological history of the area. Initially, the gypsum karst evolved as a multi-layer, semi-confined aquifer under phreatic conditions, enabling the formation of small proto-conduits in the individual gypsum beds, while the intervening marls and clays acted as impervious barriers. During a second stage, after lowering of the piezometric level, vadose conditions were established in which mechanical erosion processes in the intercalated marls and clays became predominant.. This genetic duality means that the gypsum karst at Sorbas can be taken as an example of interstratal karstification where the contemporary underground erosion processes and those of karstic evolution should be, considered products of the hydrogeological development. The total lowering of the piezometric level during the Quaternary is at least of 120 in in the centre of the basin. Interstratal vadose caves more than 120 in below the surface possess phreatic proto-channels in their upper levels which identify the past phreatic conditions in the genesis of the caves. (C) 2002 Elsevier Science B.V. All rights reserved

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