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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 sima is (spanish.) natural well that has vertical sides [10].?

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 modelling (Keyword) returned 156 results for the whole karstbase:
Showing 1 to 15 of 156
Anomalous behaviour of specific electrical conductivity at a karst spring induced by variable catchment boundaries: the case of the Podstenjšek spring, Slovenia, , Ravbar, N. , Engelhardt, I. , Goldscheider, N.

Anomalous behaviour of specific electrical conductivity (SEC) was observed at a karst spring in Slovenia during 26 high-flow events in an 18-month monitoring period. A conceptual model explaining this anomalous SEC variability is presented and reproduced by numerical modelling, and the practical relevance for source protection zoning is discussed. After storm rainfall, discharge increases rapidly, which is typical for karst springs. SEC displays a first maximum during the rising limb of the spring hydrograph, followed by a minimum indicating the arrival of freshly infiltrated water, often confirmed by increased levels of total organic carbon (TOC). The anomalous behaviour starts after this SEC minimum, when SEC rises again and remains elevated during the entire high-flow period, typically 20–40 µS/cm above the baseflow value. This is explained by variable catchment boundaries: When the water level in the aquifer rises, the catchment expands, incorporating zones of groundwater with higher SEC, caused by higher unsaturated zone thickness and subtle lithologic changes. This conceptual model has been checked by numerical investigations. A generalized finite-difference model including high-conductivity cells representing the conduit network (“discrete-continuum approach”) was set up to simulate the observed behaviour of the karst system. The model reproduces the shifting groundwater divide and the nearly simultaneous increase of discharge and SEC during high-flow periods. The observed behaviour is relevant for groundwater source protection zoning, which requires reliable delineation of catchment areas. Anomalous behaviour of SEC can point to variable catchment boundaries that can be checked by tracer tests during different hydrologic conditions.


Critical review of the kinetics of calcite dissolution and precipitation, 1979, Plummer L. N. , Parkhurst D. C. , Wigley T. M. L.

Subsidence hazard prediction for limestone terrains, as applied to the English Cretaceous Chalk, 1987, Edmonds Cn, Green Cp, Higginbottom Ie,
Soluble carbonate rocks often pose a subsidence hazard to engineering and building works, due to the presence of either metastable natural solution features or artificial cavities. There is also an inherent danger to the public and lives have been lost because of unexpected ground collapses. Although site investigation techniques are becoming increasingly elaborate, the detection of hazardous ground conditions associated with limestones is frequently difficult and unreliable. Remedial measures to solve subsidence problems following foundation failure are expensive. It would be advantageous if areas liable to subsidence could be identified in a cost-effective manner in advance of planning and ground investigation. Hazard mapping could then be used by planners when checking the geotechnical suitability of a proposed development or by engineering geologists/geotechnical engineers to design the type of ground investigation best suited to the nature and scale of the potential hazard. Recent research focussed on the English Chalk outcrop has led to the development of two new models to predict the subsidence hazard for both natural solution features and artificial cavities. The predictive models can be used to map the hazard at any given chalkland locality, as a cost-effective precursor to ground investigation. The models, although created for the Chalk outcrop, have important implications for all types of limestone terrain. The basis of the predictive modelling procedure is an analysis of the spatial distribution of nearly 1600 natural solution features, and more than 850 artificial cavity locations, identified from a wide varietyy of sources, including a special appeal organized by CIRIA. A range of geological, hydrogeological and geomorphological factors are evaluated to identify significant relationships with subsidence. These factors are ranked, numerically weighted and incorporated into two quantitative subsidence hazard model formulae. The models can be applied to perform hazard mapping

Thermal aspects of the East Midlands aquifer system, 1987, Wilson N. P. , Luheshi M. N. ,
A case study of a heat flow anomaly in the E Midlands of England is reported. The anomaly has been suggested to be an effect of water movement at depth within the E Midlands basin, with recharge to the Lower Carboniferous limestones in their outcrop, eastward movement and ascent of water up a steep faulted anticline at Eakring where the heat flow measurements were made. Numerical modelling of heat and fluid flow has been undertaken for a section running from the Peak District through Eakring to the coast. The results indicate that, although an anomaly is expected for reasonable values of hydrological parameters, its magnitude is less than that observed. The geological structure at Eakring is such that three-dimensional flow is likely to be important, and this could easily account for the discrepancy between the modelling results and the observations. The regional water flow regime has other effects on heat flow, notably the depression of heat flow above the Sherwood Sandstone aquifer

Field and modelling studies of Cambrian carbonate cycles, Virginia, Appalachians, 1989, Koerschner William F. , Read J. F. ,

Propositions pour une classification litho-gntique des phnomnes karstiques, 1990, Silvestru, E.
Proposals for a litho-genetical classification of karst and karst-like features - Based on two ubiquitous factors: lithology and core of modelling process, a separation of karst and karst-like features is proposed, into the following three categories: orthokarst, parakarst and pseudokarst, with several subcategories.

Regularities of the formation and modelling of hydrothermal karst, 1990, Dubljansky Ju. V.

An extended double-porosity concept as a practical modelling approach for a karstified terrain, 1993, Teutsch G.

Approche thorique _simplifie de la dissolution karstique, 1994, Gombert, P.
The specific behaviour of karsts makes the estimation of karstic denudation very difficult: discharge and water chemical variabili-ties are in fact major characteristics of aquifer karstic systems and cannot be properly estimated by the way of random sampling. The classical empirical methods provide generally high relative errors due to the bad knowledge of the hydrogeological catchment basin and even of the total number of springs. In the case of CORBEL's or WILLIAM's empirical formulas, average relative error can be estimated to about 100 % for a normally known aquifer karstic system : therefore it is impossible to compare different karsts that have not been studied with the same accuracy. The theoretical statisti-cal relationships between karstic denu-dation and a single climatic parameter (rainfall) are open to criticism: main authors tell that effective rainfall and pedological C02 are essential parame-ters of karstic denudation, which are never taken into account. For example, there are different PULINA's formula for different climatic types indicating that it is necessary to use another climatic parameter different from rain-fall! Moreover this way of modelling the data restrains the statistical repre-sentativity of each formula and intro-duces a difficult choice for karsts, which are at the border of two climatic types (or with mountainous parts). Another problem is the case of polar countries karsts where most precipitation is snowy and does not participate in karstic denudation. Therefore a mathematical modelling of carbonate dissolution is shown, based on infiltra-tion rate calculation and knowledge of calco-carbonic equilibrium. Temperature and rainfall are taken into account to determine the efficient part of precipitation, the productivity of pedogenetic C02 and the carbonate solubility constants. This theoretical approach gives the same results but with relative errors under 50 %. Consequently it is easy to compare different karstic countries in the world: hot and wet climates are confirmed to have the main karstogenetic activity but the role of cold countries is rehabilita-ted. Then paleokarstic denudation can be estimated.

SHALLOW KARST EXPLORATION USING MT-VLF AND DC RESISTIVITY METHODS, 1995, Guerin R. , Benderitter Y. ,
A geophysical test was carried out over a well-located and fairly embedded karstic conduit. The MT-VLF method was selected because of its high resolution and its ability to provide a resistivity parameter sensitive to water and clay. This method was used together with DC resistivity methods which allow vertical adjustment of the VLF data and show consistency between the investigation and target depths. After correcting the deformations due to the polarization of the primary field, the MT-VLF data show clearly, in the central part of the site, that the conduit does not coincide with an anomaly axis but coincides with the boundary between a conductive area and a resistive area. 2D modelling confirms that direct detection of the conduit is not feasible and that the conduit is located close to a conductive zone corresponding to a completely clay-filled fractured zone. This situation was observed on the whole site and the conduit seemed systematically to thread its way between the conductive zones to join the outlet. The distribution of the conductive fractured zones and the direction of the hydraulic gradient were two important elements in predicting the location of the conduits. A 3D approach would increase the probability of finding the conduits in such a case

Le karst du canyon du Lobos et son fonctionnement hydrogologique (Soria, Espagne), 1996, Sanzperez, E.
The massif of River Lobos, NW of the Iberian Range, is characterised by an important karst crossed by a canyon 26 km long. This canyon was dug into the Cretaceous limestones from a gradually eroded Neogene impervious cover by allogenic waters. The Cretaceous aquifer is drained by La Galiana spring. The general characteristics of the karstic relief and its hydrogeological functioning are descri-bed in this study. La Galiana spring is simulated by a mathematical model of precipitation-water flow. The results show a 4 to 5 day delay between precipi-tation and the spring flow.

Chemical and mathematical simulation of dissolving of carbonate rocks in natural waters. [in Spanish], 1996, Fagundo Juanr. , Alvarez E. , Benitez G. , Ferrera V. , Vega J.

Geomorphological evidence for anti-Apennine faults in the Umbro-Marchean Apennines and in the peri-Adriatic basin, Italy, 1996, Coltorti M, Farabollini P, Gentili B, Pambianchi G,
The Apennines are a relatively recent mountain chain which has been affected by uplift movements since the Upper Pliocene. In fact the remnants of an “erosional surface”, reduced close to base level, is preserved at the top of the relief. There is no general agreement on the geodynamic stress field and mechanisms which are creating the chain. However, it is largely accepted that uplift occurred together with the activation, on the western side of the chain, of extensive faults, oriented in the Apennine direction (NW-SE), which have been linked to the opening of the Tyrrhenian sea. A great debate is going on about the presence and significance of anti-Apennine faults (NE-SW) which have been observed by some authors but completely denied by others.The main evidence is represented by[ (1) block faulting of the remnants of the “erosional surface”. Along the Marchean Ridge, more elevated relief, delimiting relatively depressed areas, was created in correspondence with the Sibillini Mts. and Mt. S. Vicino. Similar evidence has been found in the Umbro-Marchean Ridge. Locally more than 1500 metres of displacement have been observed between more and less uplifted remnants. (2) Block faulting of fan deltas and related beaches, of Sicilian to Crotonian age, with more elevated sediments preserved between the Tronto and Tenna rivers and between the Musone and Esino rivers. Maximum displacement along a transect parallel to the coast is 200 metres. (3) fault-scarps affecting the Middle Pleistocene river terraces, as observed along the Esino, the Tronto, the Chienti and the Tenna river valleys. Maximum displacements are in the order of 50 metres. (4) Faulting of horizontal karst galleries and reorientation of the cave network, as in the Frasassi Gorge. Maximum displacements are about 100 metres. (5) Captures and alignments in the drainage network of the main river courses. (6) Large-scale gravitational movements, as in the Ancona landslide, and along the Chienti and Esino rivers.Their activation occurred in most cases after the Lower Pleistocene and although their displacements may be of relatively limited extent, dispite their recent activity, they played a major role in the modelling of the landscape. These faults display transtensive, extensional and trascurrent movements. Apart from the controversial geodynamic significance of these faults, from a geomorphological point of view they must be considered transverse elements of the stress field from blocks more or less uplifted along the Apennine chain.The importance and timing of activity of these faults in the Quaternary geomorphological evolution of the Umbria-Marchean Apennines is demonstrated using evidence usually underestimated by structural geologists, which can contribute to a debate based on a multidisciplinary approach

Petroleum geology of the Black Sea, 1996, Robinson A. G. , Rudat J. H. , Banks C. J. , Wiles R. L. F. ,
The Black Sea comprises two extensional basins formed in a back-arc setting above the northward subducting Tethys Ocean, close to the southern margin of Eurasia. The two basins coalesced late in their post-rift phases in the Pliocene, forming the present single depocentre. The Western Black Sea was initiated in the Aptian, when a part of the Moesian Platform (now the Western Pontides of Turkey) began to rift and move away to the south-east. The Eastern Black Sea probably formed by separation of the Mid-Black Sea High from the Shatsky Ridge during the Palaeocene to Eocene. Subsequent to rifting, the basins were the sites of mainly deep water deposition; only during the Late Miocene was there a major sea-level fall, leading to the development of a relatively shallow lake. Most of the margins of the Black Sea have been extensively modified by Late Eocene to recent compression associated with closure of the Tethys Ocean. Gas chromatography--mass spectrometry and carbon isotope analysis of petroleum and rock extracts suggest that most petroleum occurrences around the Black Sea can be explained by generation from an oil-prone source rock of most probably Late Eocene age (although a wider age range is possible in the basin centres). Burial history modelling and source kitchen mapping indicate that this unit is currently generating both oil and gas in the post-rift basin. A Palaeozoic source rock may have generated gas condensate in the Gulf of Odessa. In Bulgarian waters, the main plays are associated with the development of an Eocene foreland basin (Kamchia Trough) and in extensional structures related to Western Black Sea rifting. The latter continue into the Romanian shelf where there is also potential in rollover anticlines due to gravity sliding of Neogene sediments. In the Gulf of Odessa gas condensate has been discovered in several compressional anticlines and there is potential in older extensional structures. Small gas and oil discoveries around the Sea of Azov point to further potential offshore around the Central Azov High. In offshore Russia and Georgia there are large culminations on the Shatsky Ridge, but these are mainly in deep water and may have poor reservoirs. There are small compressional structures off the northern Turkish coast related to the Pontide deformation; these may include Eocene turbidite reservoirs. The extensional fault blocks of the Andrusov Ridge (Mid-Black Sea High) are seen as having the best potential for large hydrocarbon volumes, but in 2200 m of water

The applicability of numerical models to adequately characterize ground-water flow in karstic and other triple-porosity aquifers, 1996, Quinlan J. F. , Davies G. J. , Jones S. W. , Huntoon P. W.

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