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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 discharge, maximum is the maximum discharge of a river or spring during high flow conditions [16].?

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 modelling (Keyword) returned 156 results for the whole karstbase:
Showing 16 to 30 of 156
Modelling the genesis of karst aquifer systems using a coupled reactive network model., 1997,
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Clemens T. , Huckinghaus D. , Sauter M. , Liedl R. , Teutsch G.

Numerical versus statistical modelling of natural response of a karst hydrogeological system, 1997,
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Eisenlohr L, Bouzelboudjen M, Kiraly L, Rossier Y,
Structural and hydrodynamic characteristics of karst aquifers are mostly deduced from studies of global responses of karst springs (hydrographs, chemical or isotopic composition). In this case, global response is often used to make inferences with respect to infiltration and ground water How processes as well as on the hydrodynamic parameters. Obviously, the direct verification of these inferences is very difficult. We have used an indirect method of verification, introducing well defined theoretical karst structures into a finite element model and then analysing the simulated global response according to the currently accepted interpretation schemes. As we know what we are introducing into the numeric model, the consistency of the interpretation may be checked immediately. The results obtained in the hydrogeological study of two karst basins in the Swiss Jura and from 2-D and 3-D numerical simulations show the difficulty of finding structural parameters and hydrodynamic behaviour from statistical methods alone, i.e. correlation analyses discharge-discharge and precipitation-discharge. In effect, our first results show that the form of the correlograms depends on several factors besides the structure of the karst aquifer: (i) on the form of the floods. in other words the contrast between quick Row and base How, (ii) on the frequency of hydrological events during the period analysed and (iii) on the type of infiltration processes, in other words the ratio of diffuse infiltration to concentrated information. Obviously, the variability of a karst hydrograph is a result of a combination of these factors. Distinction between them is not always possible on hydrographs, and therefore on correlations (discharge-discharge and precipitation-discharge). (C) 1997 Elsevier Science B.V

The Chalk as a karstified aquifer: closed circuit television images of macrobiota, 1997,
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Waters A. , Banks D. ,
The use of closed circuit television (CCTV) imaging in the Chalk aquifer of the Thames catchment of southern England, has shed much light on the aquifer's flow mechanisms. CCTV images indicate that flow to a Chalk abstraction borehole is typically via a limited number of highly transmissive solutionenhanced fracture features. These bear some similarities to conduits found in true karstic aquifer systems, and have implications for the modelling of mass transport in the Chalk aquifer. Another feature, typical of karst aquifers, noted during CCTV surveys is the occasional presence of macroscopic biota, arthropods and annelids, apparently inhabiting the Chalk aquifer system

Role of Speleology in Karst Hydrology and Hydrogeology., 1997,
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Bonacci O.
Technology of speleological investigations enables special measurements of features of underground conduits, caves, pits, jamas, shafts and the other solutional sculpturings such as scallops and cave rocky relief. Speleologic investigations can reveal the positions, dimensions and interactions of underground and surface karst features and water flow in the karst and on its surface. Speleologists are capable of investigating the hydraulic conditions under which laminar or turbulent flows occur in conduits and small and narrow karst fractures. From such investigations crucial parameters for hydraulic, hydrologic and hydrogeologic modelling such as dissolution-bedform and hydraulically-transported sediment, can be obtained. For these reasons, the role of speleology in karst hydrology and hydrogeology should (and undoubtedly will) in future be given much more importance. This paper briefly explains the main theoretical aspects and gives some practical examples and experiences from Dinaric and others karst regions.

A modelling approach as an intermediate step for the study of protection zones in karstified limestones, 1997,
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Dassargues A. , Derouane J.

Characterization of karst aquifers by heat transfer., 1997,
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Huckinghaus D. , Liedl R. , Sauter M.
The paper presents a modelling approach which couples the hydraulically complex flow system and the heat transport processes within karst aquifers. Using this model together with quantitative measurements of flow and temperature in karst springs, it will be possible to obtain detailed information about the geometry (surface, diameter, etc.) of the conduit system.

Parameter identification in double-continuum models applied to karst aquifers., 1997,
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Mohrlok U. , Kienie J. , Teutsch G.
One modelling approach which proved successful in describing the groundwater flow within karst terraines is based on the double-continuum concept. This concept was first introduced by Teutsch (1988) and subsequently used by Teutsch & Sauter (1991), Sauter (1992), Lang (1995), Mohrlok (1996) and others to describe the ambivalent characteristics of karst aquifers. However, the approach has the drawback that the double-continuum model parameters can be determined only through model calibration (inverse approach), i.e. so far the model parameters cannot be related directly to physical field measurements. Therefore, in order to develop a better understanding of the physical significance of hydraulic parameters within double-continuum systems, a detailed numerical modeling study was conducted. For this purpose a number of synthetic but realistic karst aquifer network geometries were generated and analysed. The response of the karst network to recharge events was simulated using a detailed discrete fracture flow model with the resulting head and spring flow variographs being subsequently assumed as field measurements. This 'measured' data was then used for the calibration of a double-continuum model and the resulting parameters were compared to the original karst network geometry data. This comparison was used to develop mathematical/physical relationships between the discrete karst network geometry representing reality and the double-continuum parameter representation of it.

Modelling groundwater flow in a karst terrane using discrete and double-continuum approaches - importance of spatial and temporal distribution of recharge., 1997,
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Mohrlok U. , Sauter M.
Groundwater flow had been modelled in the karst catchment area 'Gallusquelle' (Swabian Alb, SW-Germany) using two different types of modelling approaches. The discrete and the double-continuum model differ in their respective representation of the conduit network and the formulation of the exchange flux of groundwater between fissured system and conduits. In the case of the discrete ipproach this exchange is determined by local hydraulic properties adjacent to the conduits. The double-continuum approach represents this exchange using a 'steady state', lumped parameter. As a result of this fundamental difference between the two approaches, the temporal distribution as well as the percentual allocation of groundwater recharge to conduits and fissured system plays a major role in (the respective model calibration

Karst aquifer genesis - Modelling approaches and controlling parameters, 1997,
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Sauter M. , Liedl R. , Clemens T. , Hiickinghaus D.
The quantification of regional groundwater flow and the transport of dissolved substances in a karst system generally poses problems in parameter identification as well as in the modelling of the above processes. On the other hand, available qualitative and quantitative geological information on the history of the development of karst aquifers, which can provide information on the distribution of karstitied horizons within the modelled domain, are generally not considered. A model has been developed, capable of simulating the interactions between the different processes, i.e. flow, transport coupled with carbonate dissolution, taking into account the varying boundary conditions, e.g. changes in geological and geomorphological (base level) and climatic conditions (recharge depth, temperature). A sensitivity analysis of the duration of karstification to changes in climatic parameters and physico-chemical constants of carbonate dissolution shows that the equilibrium concentration of calcium and the initial diameter of the conduits are very dominant factors.

The use of geophysical techniques in the detection of shallow cavities in limestone, MSc thesis, 1997,
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Walker, D. C.

Electromagnetic, resistivity and microgravity techniques were compared for their ability to delineate and resolve shallow natural cavity systems in limestone. Geophysical work was carried out at two field sites. Electromagnetic and resistivity constant-depth profiling surveys were carried out at Kitley Caves in Yealmpton, South Devon, with the purpose of determining the lateral extent of the already partially mapped system. Lower Long Chum Cave in Ribblesdale, North Yorkshire, was used as a control site for the testing of resistivity tomography and microgravity techniques. Several cavities had already been mapped at this site, and were known to be approximately cylindrical passages, with radii of 2-4m within a depth range of 5-20m, in the area to be surveyed.
At Kitley Caves, both the EM31 and resistivity surveys were carried out over a 20x30m grid, approximately 50m west of Western Ton's Quarry. The station interval for the EM31 survey was 2.5m, whereas resistivity readings were taken at 1m intervals. Both techniques identified a linear, low resistivity, anomaly orientated close to the primary joint direction. This feature is interpreted as a sediment-filled fissure, but excavation of the site would be required for verification.
The main Lower Long Chum Cave passage was also identified using EM mapping at 2.5m intervals. Four 155m lines were surveyed using resistivity tomography technique, with 32 electrodes at 5m spacing selected in a Wenner configuration. This survey successfully delineated Diccan Pot and Lower Long Churn caves in the locations and depth ranges expected, and also identified a previously unmapped feature that was interpreted as an air-filled cave or fissure 40m to the south of the main passage. The inversion process caused the features to be horizontally smeared to approximately twice their true dimensions, and in some cases anomalies from separate features were combined.
Lower Long Churn Cave was also successfully delineated using microgravity. Analysis of the residual Bouguer anomaly, combined with two dimensional forward modelling, implied a density contrast of 2.0g/cc, a radius of 2.1m and a depth of 5m. This agreed to within 2.5m with the depth given by resistivity. The position of the tunnel axis found using the two techniques differed by a maximum of 4m.
Resistivity tomography and microgravity were thus concluded to be techniques accurate in the delineation of shallow subsurface cavities. Future improvements in the latter method depend on the development of instruments that are sensitive enough to detect small changes in gravitational acceleration, whilst remaining relatively insensitive to background noise. Resistivity tomography is becoming an increasingly more valuable technique as refinements in the inversion process reduce smearing of anomalous features and improve the accuracy of the subsurface images produced.

Rapport entre karst et glaciers durant les glaciations dans les valles pralpines du sud des Alpes, 1998,
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Bini Alfredo, Tognini Paola, Zuccoli Luisa
At least 13 glaciations occurred during the last 2.6Ma in the Southern pre_alpine valleys. The glaciers scouring alpine and pre-alpine valleys had all the same feature, being valley temperated glaciers. Their tracks and feeding areas were always the same, just like the petrological contents of their deposits. Contrary to previous assumptions until a few years ago, the origin of these valleys and of the lakes occupying the floor of some of them (Orta, Maggiore, Como, Iseo, Garda Lakes) is due to fluvial erosion related to Messinian marine regression. The valley slopes modelling is Messinian in age, too, while most caves are older. As a general rule, glaciers worked on valley slopes just as a re_modelling agent, while their effects were greater on valley floors. The karstic evolution began as soon as the area was lifted above sea level (upper Oligocene - lower Miocene), in a palaeogeographical environment quite different from the present one, although the main valley floors were already working as a base level. During Messinian age, the excavation of deep canyons along pre-existing valleys caused a dramatic lowering of the base level, followed by a complete re-arrangement of the karstic networks, which got deeper and deeper. The Pliocene marine transgression caused a new re-arrangement, the karst network getting mostly drowned under sea level. During these periods, the climate was hot-wet tropical, characterised by a great amount of water circulating during the wet season. At the same time tectonic upliftings were at work, causing breaking up of the karst networks and a continuous rearrangement of the underground drainage system. In any case, karstic networks were already well developed long before the beginning of Plio-Quaternary glaciations. During glaciations, karst systems in pre-alpine valleys could have been submitted to different drainage conditions, being: a) isolated, without any glacial water flowing; b) flooded, connected to the glacier water-filled zone; c) active, scoured by a stream sinking at glacier sides or in a sub glacial position. The stream could flow to the flooded zone (b), or scour all the unflooded system long down to the resurgence zone, the latter being generally located in a sub glacier position. The glacier/karst system is a very dynamic one: it could get active, flooded or isolated depending on endo- and sub-glacial drainage variations. Furthermore, glaciers show different influences on karstic networks, thus working with a different effect during their advance, fluctuations, covering and recession phases. Many authors believe, or believed, the development of most surface and underground karst in the Alps is due to glaciations, with the last one held to be mostly responsible for this. Whatever the role of glaciers on karstic systems, in pre-alpine valleys caves, we do not have evidence either of development of new caves or of remarkable changes in their features during glaciations. It is of course possible some pits or galleries could have developed during Plio-Quaternary glaciations, but as a general rule glaciers do not seem to have affected karstic systems in the Southern pre-alpine valleys with any remarkable speleogenetic effects: the glaciers effects on them is generally restricted to the transport of great amounts of debris and sediments into caves. The spotting of boulders and pebbles trapped between roof stalactites shows that several phases of in- and out-filling of galleries occurred with no remarkable changing in pre-dating features, including cave decorations. The presence of suspended karst systems does not prove a glacial origin of the valleys, since most of them pre-date any Plio-Quaternary glaciation, as shown by calcite cave deposits older than 1,5Ma. The sediments driven into caves might have caused a partial or total occlusion of most galleries, with a remarkable re-arrangement of the underground drainage system. In caves submitted to periglacial conditions all glaciations long, we can find deposits coming from weathered surface sediments, sharp-edged gelifraction debris and, more rarely, alluvial deposits whose origin is not related to the circulation of the glacial meltwater. In caves lower than or close to the glaciers limit we generally find large amounts of glacier-related deposits, often partly or totally occluding cave galleries. These sediments may be directly related to glaciers, i.e. carried into caves by glacial meltwaters, resulting from surface glacial deposit erosion. They generally show 3 dominant facies: A) lacustrine deposits; B) alluvial deposits and C) debris flow deposits facies. The only way of testing the soundness of the forementioned hypothesis is to study the main characters and spreading of cave sediments, since they are the only real data on connection of glaciers to endokarst networks.

Modelling of karst structures by geophysical methods. An example: the doline of S Pietro dei Monti (Western Liguria), 1998,
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Armadillo E, Massa F, Caneva G, Gambetta M, Bozzo E,
Integrated geophysical investigations of karat structures were carried out in Liguria and Piedmont (NW Italy); this paper refers to the S. Pietro dei Monti doline, in the karat area of Mt. Carmo (Savona). The techniques used in the integrated study were magnetics, electromagnetics and seismic refraction. The target was to identify, without drilling, the nature of the doline, for example if it is of dissolution or collapse type. A preliminary susceptibility sampling of the outcrop and topsoil and the diffuse fractures with a probable water seepage suggested magnetics and VLF electromagnetics. Such methods applied in an area with an extremely low cultural noise allowed modelling of the buried structure of the doline

Evolution of size distributions of natural particles during aggregation: modelling versus field results, 1998,
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Atteia O,
In this paper a discretized model simulating aggregation of size distributions jointly with sedimentation and transport is presented. A review of the current theory provides some helpful hints about the relative importance of each aggregation process, i.e. Brownian motion, shear flow and differential sedimentation, which are tested by using collision efficiency factors. The novel aspect of the model arises from the use of a varying mean particle diameter in each size class. This allows both non-steady-state and steady-state calculations and free choice of size classes. A comparison with a classical approach shows the exactitude of the results and the improvment obtained for several cases. The simulations gave a family of curves characterized by three parts corresponding to peri-, and orthokinetic aggregation and to sedimentation. The role of collision effciency is crucial in the relative extent of each part of the size distribution. The comparison with a series of data from a karst spring showed that the model was able to fit most of the particle size distributions using significant values of each parameter. This allowed information about particle aggregation and transport within a non-accessible aquifer to be inferred.

Mapping Chicxulub crater structure with gravity and seismic reflection data, 1998,
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Hildebrand A. R. , Pilkington M. , Ortizaleman C. , Chavez R. E. , Urrutiafucugauchi J. , Connors M. , Granielcastro E. , Camarazi A. , Halpenny J. F. , Niehaus D. ,
Aside from its significance in establishing the impact-mass extinction paradigm, the Chicxulub crater will probably come to exemplify the structure of large complex craters. Much of Chicxulub's structure may be mapped' by tying its gravity expression to seismic-reflection profiles revealing an [~]180 km diameter for the now-buried crater. The distribution of karst topography aids in outlining the peripheral crater structure as also revealed by the horizontal gradient of the gravity anomaly. The fracturing inferred to control groundwater flow is apparently related to subsidence of the crater fill. Modelling the crater's gravity expression based on a schematic structural model reveals that the crater fill is also responsible for the majority of the negative anomaly. The crater's melt sheet and central structural uplift are the other significant contributors to its gravity expression. The Chicxulub impact released [~]1.2 x 1031 ergs based on the observed collapsed disruption cavity of [~]86 km diameter reconstructed to an apparent disruption cavity (Dad) of [~]94 km diameter (equivalent to the excavation cavity) and an apparent transient cavity (Dat) of [~]80 km diameter. This impact energy, together with the observed [~]2 x 1011 g global Ir fluence in the Cretaceous-Tertiary (K-T) fireball layer indicates that the impactor was a comet estimated as massing [~]1.8 x 1018 g of [~]16.5 km diameter assuming a 0.6 gcm-3 density. Dust-induced darkness and cold, wind, giant waves, thermal pulses from the impact fireball and re-entering ejecta, acid rain, ozone-layer depletion, cooling from stratospheric aerosols, H2O greenhouse, CO2 greenhouse, poisons and mutagens, and oscillatory climate have been proposed as deleterious environmental effects of the Chicxulub impact with durations ranging from a few minutes to a million years. This succession of effects defines a temperature curve that is characteristic of large impacts. Although some patterns may be recognized in the K-T extinctions, and the survivorship rules changed across the boundary, relating specific environmental effects to species' extinctions is not yet possible. Geochemical records across the boundary support the occurrence a prompt thermal pulse, acid rain and a [~]5000 year-long greenhouse. The period of extinctions seems to extend into the earliest Tertiary

The genesis of dedolomites: a disussion based on reactive transport modelling, 1998,
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Ayora C. , Taberner C. , Saaltink M. W. , Carrera J.

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