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Enviroscan Ukrainian Institute of Speleology and Karstology

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Speleology in Kazakhstan

Shakalov on 04 Jul, 2018
Hello everyone!   I pleased to invite you to the official site of Central Asian Karstic-Speleological commission ("Kaspeko")   There, we regularly publish reports about our expeditions, articles and reports on speleotopics, lecture course for instructors, photos etc. ...

New publications on hypogene speleogenesis

Klimchouk on 26 Mar, 2012
Dear Colleagues, This is to draw your attention to several recent publications added to KarstBase, relevant to hypogenic karst/speleogenesis: Corrosion of limestone tablets in sulfidic ground-water: measurements and speleogenetic implications Galdenzi,

The deepest terrestrial animal

Klimchouk on 23 Feb, 2012
A recent publication of Spanish researchers describes the biology of Krubera Cave, including the deepest terrestrial animal ever found: Jordana, Rafael; Baquero, Enrique; Reboleira, Sofía and Sendra, Alberto. ...

Caves - landscapes without light

akop on 05 Feb, 2012
Exhibition dedicated to caves is taking place in the Vienna Natural History Museum   The exhibition at the Natural History Museum presents the surprising variety of caves and cave formations such as stalactites and various crystals. ...

Did you know?

That gravity spring is see spring, gravity.?

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

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What is Karstbase?



Browse Speleogenesis Issues:

KarstBase a bibliography database in karst and cave science.

Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
See all featured articles
Featured articles from other Geoscience Journals
Karst environment, Culver D.C.
Mushroom Speleothems: Stromatolites That Formed in the Absence of Phototrophs, Bontognali, Tomaso R.R.; D’Angeli Ilenia M.; Tisato, Nicola; Vasconcelos, Crisogono; Bernasconi, Stefano M.; Gonzales, Esteban R. G.; De Waele, Jo
Calculating flux to predict future cave radon concentrations, Rowberry, Matt; Marti, Xavi; Frontera, Carlos; Van De Wiel, Marco; Briestensky, Milos
Microbial mediation of complex subterranean mineral structures, Tirato, Nicola; Torriano, Stefano F.F;, Monteux, Sylvain; Sauro, Francesco; De Waele, Jo; Lavagna, Maria Luisa; D’Angeli, Ilenia Maria; Chailloux, Daniel; Renda, Michel; Eglinton, Timothy I.; Bontognali, Tomaso Renzo Rezio
Evidence of a plate-wide tectonic pressure pulse provided by extensometric monitoring in the Balkan Mountains (Bulgaria), Briestensky, Milos; Rowberry, Matt; Stemberk, Josef; Stefanov, Petar; Vozar, Jozef; Sebela, Stanka; Petro, Lubomir; Bella, Pavel; Gaal, Ludovit; Ormukov, Cholponbek;
See all featured articles from other geoscience journals

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Your search for components (Keyword) returned 137 results for the whole karstbase:
Showing 121 to 135 of 137
Relative importance of the saturated and the unsaturated zones in the hydrogeological functioning of karst aquifers: The case of Alta Cadena (Southern Spain), 2011,
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Mudarra M. , Andreo B.

From analysis of the hydrodynamic and hydrochemical responses of karst springs, it is possible to know the behaviour of the aquifers they drain. This manuscript aims to contribute to the characterization of infiltration process, and to determine the relative importance of the saturated zone and of the unsaturated zone in the hydrogeological functioning of carbonate aquifers, using natural hydrochemical tracers. Thus, chemical components together with temperature and electrical conductivity (both punctual and continuous records) have been monitored in three springs which drain Alta Cadena carbonate aquifer, Southern Spain. An evaluation of the percentage of the electrical conductivity frequency peaks determined for each of the three springs is linked to the chemical parameters that comprise the conductivity signal. One of these springs responds rapidly to precipitation (conduit flow system), due to the existence of a high degree of karstification in the unsaturated zone and in the saturated zone, both of which play a similar role in the functioning of the spring. Another spring responds to precipitation with small increases in water flow, somewhat lagged, because the aquifer has a low degree of karstification, even in the unsaturated zone, which seems to influence its functioning more strongly than does the saturated zone. The third spring drains a sector of the aquifer with a moderately developed degree of karstification, one that is intermediate between the other two, in which both the unsaturated zone and the saturated zone participate in the functioning of the spring, but with the latter zone having a stronger influence. These three springs show different hydrogeological functioning although they are in similar geological and climatic contexts, which show the heterogeneity of karst media and the importance of an adequate investigation for groundwater management and protection in karst areas.

Research highlights
- From analysis of the hydrodynamic and hydrochemical responses of karst springs. - Characterization of the relative importance of the saturated (SZ) and unsaturated (NSZ) zones - Villanueva del Rosario: NSZ and SZ play similar roles in the functioning of the system. ► Pita: NSZ seems to affect its functioning more than SZ. - Parroso: NSZ and SZ participate in the functioning of the system, but SZ is more active.

Mineralogy of Iza Cave (Rodnei Mountains, N. Romania), 2011,
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Tă, Maş, Tudor, Kristly Ferenc, Barbutudoran Lucian

The secondary minerals from Iza Cave result from the interactions of karst water and/or cave atmosphere over a variety of sedimentary and metamorphic rocks. The cave passages expose at various extents Eocene limestones and conglomerates, Oligocene black shales, Upper Precambrian micaschists, marble and dolomitic marble and associated ore deposits.
Twelve secondary minerals identified in the cave (carbonates, sulfates, phosphates, oxides and hydroxides, and silicates) are presented in this study. Calcite, aragonite, gypsum, brushite and hydroxylapatite are the components of common speleothems in the limestone, dolomite and conglomerate areas of the cave. Ankerite crusts are related to areas with pyrite mineralization within the metamorphic carbonate rocks. Goethite, jarosite, hematite and gypsum form various speleothems in the sectors within micaschists and conglomerates. Large weathering deposits occurring in passage areas developed within micaschists consist of illite, kaolinite, jarosite, goethite, gypsum and alunite. The extent of the weathering deposits occurring on non-karst rocks in the underground environment makes this cave a particularly interesting site for studies of water-rock interactions.

Influence of Karst Landscape on Planetary Boundary Layer Atmosphere: A Weather Research and Forecasting (WRF) ModelBased Investigation, 2011,
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Leeper R. Mahmood R, Quintanar A. I.

Karst hydrology provides a unique set of surface and subsurface hydrological components that affect soilmoisture variability. Over karst topography, surface moisture moves rapidly below ground via sink holes,vertical shafts, and sinking streams, reducing surface runoff and moisture infiltration into the soil. In addition,subsurface cave blockage or rapid snowmelt over karst can lead to surface flooding. Moreover, regionsdominated by karst may exhibit either drier or wetter soils when compared to nonkarst landscape. However,because of the lack of both observational soil moisture datasets to initialize simulations and regional landsurface models (LSMs) that include explicit karst hydrological processes, the impact of karst on atmosphericprocesses is not fully understood. Therefore, the purpose of this study was to investigate the importance ofkarst hydrology on planetary boundary layer (PBL) atmosphere using the Weather Research and ForecastingModel (WRF). This research is a first attempt to identify the impacts of karst on PBL. To model the influenceof karst hydrology on atmospheric processes, soil moisture was modified systematically over the WesternKentucky Pennyroyal Karst (WKYPK) region to produce an ensemble of dry and wet anomaly experiments.Simulations were conducted for both frontal- and nonfrontal-based convection. For the dry ensemble, cloudcover was both diminished downwind of karst because of reduced atmospheric moisture and enhanced slightlyupwind as moist air moved into a region of increased convection compared to control simulations (CTRL).Moreover, sensible (latent) heat flux and PBL heights were increased (decreased) compared to CTRL. Inaddition, the wet ensemble experiments reduced PBL heights and sensible heat flux and increased cloud coverover karst compared to CTRL. Other changes were noted in equivalent potential temperature (ue) andvertical motions and development of new mesoscale circulation cells with alterations in soil moisture overWKYPK. Finally, the location of simulated rainfall patterns were altered by both dry and wet ensembles withthe greatest sensitivity to simulated rainfall occurring during weakly forced or nonfrontal cases. Simulatedrainfall for the dry ensemble was more similar to the North American Regional Reanalysis (NARR) thanCTRL for the nonfrontal case. Furthermore, the initial state of the atmosphere and convective triggers werefound to either enhance or diminish simulated atmospheric responses

A new karren feature: hummocky karren, 2012,
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Plan Lukas, Renetzeder Christa, Pavuza Rudolf, Krner Wilfried

Karren are small-scale landforms on karst surfaces and many types have been described so far. Here we present an apparently new feature which was found on the Hochschwab karst massive in the Northern Calcareous Alps of Austria. So far only few outcrops each having less than 1 m² within a very restricted area have been found. Morphometric analysis reveals that the karren consist of a randomly distributed, dispersed assemblage of small hummocks and depressions in between. The mean distance between neighbouring hummocks is 4 to 5 cm and the mean height is 0.85 cm. Longitudinal sections are gently sinuous. The occurrences are delimited by thin soil cover with grassy vegetation. The karst features continue below that vegetation cover. Therefore, it is clear that the karren have formed subcutaneously. Corroded fissures where water could infiltrate into the epikarst are absent. The bedrock lithology is Middle Triassic limestone of the Wetterstein Formation in lagoonal facies. Geological structures do not govern the feature. The surface is not a bedding plane and small joints and fractures do not govern the arrangement of the hummocks. Thin section analysis regarding rock texture and dolomite components show that there is no compositional difference between hummocks and depressions. Geochemical analyses show that the limestone is very pure with a very low content of Magnesia. Slightly higher Magnesia contents at the hummock surfaces are significant. The data obtained so far only indicate that some dissolution mechanism but not any rock property governs the irregular array. As there exist no descriptions of comparable features in literature, the name “hummocky karren” is suggested for that type of karren landform.

Radionuclides as natural tracers for the characterization of fluids in regional discharge areas, Buda Thermal Karst, Hungary, 2012,
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Eross A. , Mdlszonyi J. , Surbeck H. , Horvth . , Goldscheider N. , Csoma A. .

The Buda Thermal Karst (Budapest, Hungary) developed in the regional discharge zone of a carbonate rock aquifer system. High radioactivity of the spring waters has already been reported in 1912, but there has been no detailed study and no consistent explanation for its origin. In this area mixing of cold and hot karst waters was hitherto assigned to be responsible for cave formation. However, the dissimilarity of the discharging waters within Budapest (in the North: Rozsadomb; in the South: Gellert Hill), may suggest also different cave forming processes. The application of radionuclides as natural tracers represents a novel approach to investigate these questions. For this study, we used uranium, radium and radon to identify mixing of fluids in the Buda Thermal Karst system and to infer the temperature and chemical composition of the end members. Chloride as a conservative component allowed the mixing ratios for the sampled waters to be calculated. Their fluid compositions were modeled and through the comparison of modeled and measured values, the end members were validated. As the result of this study, it was possible to characterize the mixing end members for the Rozsadomb area, whereas for the Gellert Hill discharge zone, mixing components could not be identified with the aid of radionuclides. Therefore, it is suggested that different processes are responsible for cave formation in these areas. In the Rozsadomb area, structurally-controlled mixing is the dominant cave forming process, whereas in the Gellert Hill area, due to the lack of mixing members, other processes have to be found, which are responsible for the formation of the caves, such as retrograde calcite solubility and/or geogenic acids, such as H2S. The application of radionuclides thus further supported the differences between the two study areas. This study identified moreover the source of elevated radon content of the waters in the Gellert Hill area in form of iron-hydroxide precipitates that accumulate in the spring caves. These precipitates are highly efficient in adsorbing radium, which generates radon by alpha decay, and hence act as local radon source for the waters. In this study we showed that uranium, radium and radon naturally occurring in groundwater can be used to characterize fluids of different flow systems in regional discharge areas owing to the contrasting geochemical behaviors of these elements

Simulation of flow processes in a large scale karst system with an integrated catchment model (Mike She) Identification of relevant parameters influencing spring discharge, 2012,
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Doummar J. , Sauter M. , Geyer T.

In a complex environment such as karst systems, it is difficult to assess the relative contribution of the different components of the system to the hydrological system response, i.e. spring discharge. Not only is the saturated zone highly heterogeneous due to the presence of highly permeable conduits, but also the recharge processes. The latter are composed of rapid recharge components through shafts and solution channels and diffuse matrix infiltration, generating a highly complex, spatially and temporally variable input signal. The presented study reveals the importance of the compartments vegetation, soils, saturated zone and unsaturated zone. Therefore, the entire water cycle in the catchment area Gallusquelle spring (Southwest Germany) is modelled over a period of 10 years using the integrated hydrological modelling system Mike She by DHI (2007). Sensitivity analyses show that a few individual parameters, varied within physically plausible ranges, play an important role in reshaping the recessions and peaks of the recharge functions and consequently the spring discharge. Vegetation parameters especially the Leaf Area Index (LAI) and the root depth as well as empirical parameters in the relationship of Kristensen and Jensen highly influence evapotranspiration, transpiration to evaporation ratios and recharge respectively. In the unsaturated zone, the type of the soil (mainly the hydraulic conductivity at saturation in the water retention and hydraulic retention curves) has an effect on the infiltration/evapotranspiration and recharge functions. Additionally in the unsaturated karst, the saturated moisture content is considered as a highly indicative parameter as it significantly affects the peaks and recessions of the recharge curve. At the level of the saturated zone the hydraulic conductivity of the matrix and highly conductive zone representing the conduit are dominant parameters influencing the spring response. Other intermediate significant parameters appear to influence the characteristics of the spring response yet to a smaller extent, as for instance bypass and the parameters a in the Van Genuchten relation for soil moisture content curves.

Spatially dense drip hydrological monitoring and infiltration behaviour at the Wellington Caves, South East Australia, 2012,
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Jex Catherine N. , Mariethoz Gregoire, Baker Andy, Graham Peter, Andersen Martin S. , Acworth Ian, Edwards Nerilee, Azcurra Cecilia

Despite the fact that karst regions are recognised as significant groundwater resources, the nature of groundwater flow paths in the unsaturated zone of such fractured rock is at present poorly understood. Many traditional methods for constraining groundwater flow regimes in karst aquifers are focussed on the faster drainage components and are unable to inform on the smaller fracture or matrix-flow components of the system. Caves however, offer a natural inception point to observe both the long term storage and the preferential movement of water through the unsaturated zone of such fractured carbonate rock by monitoring of drip rates of stalactites, soda straws and seepage from fractures/micro fissures that emerge in the cave ceiling. Here we present the largest spatial survey of automated cave drip rate monitoring published to date with the aim of better understanding both karst drip water hydrogeology and the relationship between drip hydrology and surface climate. By the application of cross correlation functions and multi-dimensional scaling, clustered by k-means technique, we demonstrate the nature of the relationships between drip behaviour and initial surface infiltration and similarity amongst the drip rate time series themselves that may be interpreted in terms of flow regimes and cave chamber morphology and lithology.

Carbon cycle in the epikarst systems and its ecological effects in South China, 2012,
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Jiang Z. , Lian Y. , Qin X.

The carbon cycle in a global sense is the biogeochemical process by which carbon is exchanged among the biosphere, pedosphere, geosphere, hydrosphere, and atmosphere of the earth. For epikarst systems, it is the exchange of carbon among the atmosphere, water, and carbonate rocks. Southern China is located in the subtropical zone; its warm and humid weather creates favorable conditions for the dynamic physical, chemical, and ecological processes of the carbon cycle. This paper presents the mechanisms and characteristics of the carbon cycle in the epikarst systems in south China. The CO2 concentration in soils has clear seasonal variations, and its peak correlates well with the warm and rainy months. Stable carbon isotope analysis shows that a majority of the carbon in this cycle is from soils. The flow rate and flow velocity in an epikarst system and the composition of carbonate rocks control the carbon fluxes. It was estimated that the karst areas in south China contribute to about half of the total carbon sink by the carbonate system in China. By enhancing the movement of elements and dissolution of more chemical components, the active carbon cycle in the epikarst system helps to expand plant species. It also creates favorable environments for the calciphilic plants and biomass accumulation in the region. The findings from this study should help in better understanding of the carbon cycle in karst systems in south China, an essential component for the best management practices in combating rock desertification and in the ongoing study of the total carbon sink by the karst flow systems in China

Spent carbide waste retains toxicity long term after disposal in caves and mines , 2012,
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Semikolennykh Andrew A. , Rahleeva Anna A. , Poputnikova Tatjana B.
We studied the environmental impact of wastes derived from calcium carbide, which is widely used for generating acetylene in industry and speleology. It was shown that spent carbide is toxic for biota and harmful to cave ecosystems and the surrounding environment. The toxic components of spent carbide waste were found to include calcium hydroxide, strontium and polycyclic aromatic hydrocarbons. The 50% lethal doses (LD 50%) of fresh spent carbide waste were calculated as 0.28-0.32 g/l in biotests with daphnia, infusoria, and fishes. The toxicity of spent carbide declined only slowly over time, with toxicity still present in 13-year-old samples. Spent carbide should be disposed of with great care to ensure that it cannot be disseminated into natural water systems. Spent carbide deactivation could be provided within isolated bowls filled with water (micro sediment bowls) or within water-proof storage containers, and complete recycling could be achieved through the addition of deactivated waste to solid building materials.

Five Blues Lake National Park, Belize: a cautionary management tale, 2012,
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Day M. , Reynolds B. ,

Karst is inherently dynamic, and this may be manifest in unexpected ways, which may have major implications for management of protected areas, where changes may have major impacts on visitor numbers and revenue streams. In Five Blues Lake National Park, Belize, the principal visitor focus is Five Blues Lake itself. An anomalous feature with characteristics of a karst window or cenote but in the setting of a polje or ponor lake, Five Blues has both surface and underground drainage components. Establishment of the national park proceeded under the impression that the lake was a permanent feature, but over July 20 to 25, 2006, the lake drained rapidly underground. Without the lake, visitor numbers and park revenues declined, and the park was all but abandoned. The lake refilled in 2007, but visitor numbers continue to lag. Management and promotion of hydrologic features within protected areas needs to take such possibilities into account, emphasizing variability and change and avoiding a focus on conditions that may not prevail at any given time.

Cure from the cave: volcanic cave actinomycetes and their potential in drug discovery, 2013,
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Cheeptham N. , Sadoway T. , Rule D. , Watson K. , Moote P. , Soliman L. C. , Azad N. , Donkor K. K. , Horne D.

Volcanic caves have been little studied for their potential as sources of novel microbial species and bioactive compounds with new scaffolds. We present the first study of volcanic cave microbiology from Canada and suggest that this habitat has great potential for the isolation of novel bioactive substances. Sample locations were plotted on a contour map that was compiled in ArcView 3.2. Over 400 bacterial isolates were obtained from the Helmcken Falls cave in Wells Gray Provincial Park, British Columbia. From our preliminary screen, of 400 isolates tested, 1% showed activity against extended spectrum ß-lactamase E. coli, 1.75% against Escherichia coli, 2.25% against Acinetobacter baumannii, and 26.50% against Klebsiella pneumoniae. In addition, 10.25% showed activity against Micrococcus luteus, 2% against methicillin resistant Staphylococcus aureus, 9.25% against Mycobacterium smegmatis, 6.25% Pseudomonas aeruginosa and 7.5% against Candida albicans. Chemical and physical characteristics of three rock wall samples were studied using scanning electron microscopy and f lame atomic absorption spectrometry. Calcium (Ca), iron (Fe), and aluminum (Al) were the most abundant components while magnesium (Mg), sodium (Na), arsenic (As), lead (Pb), chromium (Cr), and barium (Ba) were second most abundant with cadmium (Cd) and potassium (K) were the least abundant in our samples. Scanning electron microscopy (SEM) showed the presence of microscopic life forms in all three rock wall samples. 16S rRNA gene sequencing of 82 isolates revealed that 65 (79.3%) of the strains belong to the Streptomyces genus and 5 (6.1%) were members of Bacillus, Pseudomonas, Nocardia and Erwinia genera. Interestingly, twelve (14.6%) of the 16S rRNA sequences showed similarity to unidentif ied ribosomal RNA sequences in the library databases, the sequences of these isolates need to be further investigated using the EzTaxon-e database (http://eztaxon-e. to determine whether or not these are novel species. Nevertheless, this suggests the possibility that they could be unstudied or rare bacteria. The Helmcken Falls cave microbiome possesses a great diversity of microbes with the potential for studies of novel microbial interactions and the isolation of new types of antimicrobial agents.

Atmospheric Processes in Caves, 2013,
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James, J. M.

The cave atmosphere is placed in context as a geomorphic agent. The composition of cave air in well-ventilated caves isgoverned by exchange between surface and cave air. In poorly ventilated caves, its composition can be altered by dilution and production, and depletion of its components in the cave. Relative humidity is used to introduce water vapor as a critical component of cave air and its variations that result in evaporation of water and condensation of water vapor. The biogenicand inorganic reactions of oxygen and carbon dioxide control solution of limestone and precipitation of calcite. Condensation corrosion is a visual manifestation of atmospheric processes on bedrock and speleothems. Theories and experiment shave resulted in rates for condensation corrosion, which allow a preliminary assessment of its role as aspeleogenetic agent. The cave air carries particulates of both biogenic and inorganic origin; these can influence geomorphic processes in caves and provide significant paleoenvironmental information so as to past cave and surface events and climates. It is concluded that anthropogenic impacts can alter the atmospheric processes in caves.

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Florea Lee J.


This manuscript offers preliminary geochemical evidence that investigates the potential for hypogene speleogenesis in the Cumberland Plateau of southeastern Kentucky, U.S.A. The region was traditionally considered a classic example of epigenic karst, but new insights have uncovered tantalizing observations that suggest alternatives to simple carbonic acid speleogenesis. Such first-order observations have included natural petroleum seeps at the surface and in caves, occasional cave morphologies consistent with action of hypogene fluids, and prolific gypsum within cave passages. To this point, geochemical data from caves and springs verify carbonic acid as the primary dissolutional agent; however, these same analyses cannot rule out sulfuric acid as a secondary source of dissolution. In this paper, Principal Component Analysis of ionic data reveals two components that coordinate with parameters associated with “karst water” and shallow brine. In contrast, molar ratios of Ca+ and Mg+ as compared to HCO3 - and SO4 2- closely follow the reaction pathway stipulated by the carbonate equilibria reactions. Despite these data, the role, if any, of hypogene speleogenesis in the karst of the Cumberland Plateau remains inconclusive. It is very likely that carbonic acid dominates speleogenesis; however, contributions from sulfuric acid may influence our understanding of “inception” and carbon flux within these aquifers.

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Andreychouk Viacheslav, Tyc Andrzej

Karst hazards are an important example of natural hazards. They occur in areas with soluble rocks (carbonates, mostly limestone, dolomite, and chalk; sulfates, mostly gypsum and anhydrite; chlorides, mostly rock salt and potassium salt; and some silicates, quartzite and amorphous siliceous sediments) and efficient underground drainage. Karst is one of the environments in the world most vulnerable to natural and human-induced hazards. Karst hazards involve fast-acting processes, both on the surface and underground (e.g., collapse, subsidence, slope movements, and floods) and their effects (e.g., sinkholes, degraded aquifers, and land surface). They frequently cause serious damage in karst areas around the world, particularly in areas of intense human activity. Karst threat is the potential hazard to the life, health, or welfare of people and infrastructure, arising from the particular geological structure and function of karst terrains. The presence of underground cavities in the karst massif masks the threat from the hazards of collapse. This means that in some instances, the potential threats from karst, which are inherent features of the karst environment, become hazards. They range in category from potential to real. The term (karst hazards) is related to two other terms, used mostly in applied geosciences, particularly engineering geology – risk assessment and mitigation. Risk is the probability of an occurrence, and the consequential damages are defined as hazards. Risk assessment is the determination of quantitative or qualitative value of risk related to a concrete situation and a recognized hazard. Quantitative risk assessment requires calculations of two components: the magnitude of the potential loss and the probability that the loss will occur. Risk assessment is a step in a risk management. Mitigation may be defined as the reduction of risk to life and the environment by reducing the severity of collapse or subsidence, building subsidence-resistant constructions, restricting land use, etc.

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Bayari C. S. , Ozyurt N. N.

Initiation and development of karstification requires a con­tinuous flushing of pore water in equilibrium with carbon­ate minerals. Under confined flow conditions, the energy required for pore water transport is supplied by external pressure sources in addition to the by earth’s gravity. Earth tides and water loads over the confined flow system are the main sources of ex­ternal pressure that drives the pore water. Earth tides, created by the sum of the horizontal components of tide generation forces of moon and sun, causes expansion and contraction of the crust in horizontal direction. Water load on top of the confined flow system causes vertical loading/unloading and may be in the form of recharge load or ocean loading in the inland and sub-oceanic settings, respectively. Increasing and decreasing tide generating force results in pore water transport in the confined system by means of contraction and expansion, respectively. Since these forces operate in perpendicular directions, pore water flushing by earth tides becomes less effective when water load on top of the confined flow system increases. Temporal variation of fresh­water content in a submarine cave is presented as an example of groundwater discharge driven by earth tides and recharge load.

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