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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 Peclet number is 1. measure of the relative contribution of mechanical dispersion and diffusion to solute transport. it relates the effectiveness of mass transport by advection to the ??????????????vx d c x p c x e ????????????effectiveness of mass transport by either dispersion or diffusion . peclet p c x e ??????????????????2 2 numbers below .0.4 indicate diffusion/dispersion control; 0.4-6.0 suggest that diffusion/dispersion and advection are in transition and thus approximately equal to each other; and >6.0 indicate advection control. large peclet numbers indicate strongly advective systems. 2. a relationship between the advective and diffusive components of solute transport expressed as the ratio of the product of the average interstitial velocity, times the characteristic length, divided by the coefficient of molecular diffusion. small values indicate diffusion dominance, large values indicate advection dominance [22].?

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Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
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Featured articles from other Geoscience Journals
Karst environment, Culver D.C.
Mushroom Speleothems: Stromatolites That Formed in the Absence of Phototrophs, Bontognali, Tomaso R.R.; D’Angeli Ilenia M.; Tisato, Nicola; Vasconcelos, Crisogono; Bernasconi, Stefano M.; Gonzales, Esteban R. G.; De Waele, Jo
Calculating flux to predict future cave radon concentrations, Rowberry, Matt; Marti, Xavi; Frontera, Carlos; Van De Wiel, Marco; Briestensky, Milos
Microbial mediation of complex subterranean mineral structures, Tirato, Nicola; Torriano, Stefano F.F;, Monteux, Sylvain; Sauro, Francesco; De Waele, Jo; Lavagna, Maria Luisa; D’Angeli, Ilenia Maria; Chailloux, Daniel; Renda, Michel; Eglinton, Timothy I.; Bontognali, Tomaso Renzo Rezio
Evidence of a plate-wide tectonic pressure pulse provided by extensometric monitoring in the Balkan Mountains (Bulgaria), Briestensky, Milos; Rowberry, Matt; Stemberk, Josef; Stefanov, Petar; Vozar, Jozef; Sebela, Stanka; Petro, Lubomir; Bella, Pavel; Gaal, Ludovit; Ormukov, Cholponbek;
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Your search for karst genesis (Keyword) returned 30 results for the whole karstbase:
Showing 16 to 30 of 30
Karst genetic model for the French Bay Breccia deposits, San Salvador, Bahamas., 2001, Florea L. , Mylroie J. , Carew J.
On the Island of San Salvador in the Bahama archipelago 30 breccia deposits can be found along the French Bay sea cliffs on the southeastern coast of the island. Breccia deposits of this type have not been observed on any other location on the island. These deposits have traditionally been interpreted as paleo-talus deposits from an eroding sea cliff formed on a transgressive eolianite deposited at the start of the oxygen isotope substage 5e sea-level highstand (ca. 125,000 years before present). New evidence supports a karst genesis. A survey of several deposits revealed a vertical restriction of +2 to +7 meters above sea level consistent with flank margin caves developed during the substage 5e still-stand. The morphologies of the features were found to be globular and contain distinct caliche boundaries, overhung lips, and smooth undulating bases. Petrographic results support a model in which voids are created and then infilled with a soil breccia. It can be concluded from these results that the deposits reflect qualities of a lithified soil breccia filling in breached flank margin caves. karst breccia, paleokarst, San Salvador

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

Characterisation of karst systems by simulating aquifer genesis and spring responses: model development and application to gypsum karst., 2002, Birk S.
Karst aquifers are important groundwater resources, which are highly vulnerable to contamination due to fast transport in solutionally enlarged conduits. Management and protection of karst water resources require an adequate aquifer characterisation at the catchment scale. Due to the heterogeneity and complexity of karst systems, this is not easily achieved by standard investigation techniques such as pumping tests. Therefore, a process-based numerical modelling tool is developed, designed to support the karst aquifer characterisation using two complementary approaches: Firstly, the simulation of conduit enlargement, which aims at predicting aquifer properties by forward modelling of long-term karst genesis; secondly, the simulation of heat and solute transport processes, which aims at inferring aquifer properties from short-term karst spring response after recharge events. Karst genesis modelling is applied to a conceptual setting based on field observations from the Western Ukraine, where the major part of known gypsum caves is found. Gypsum layers are typically supplied by artesian flow of aggressive water from insoluble aquifers underneath. Processes and parameters, controlling solutional enlargement of single conduits under artesian conditions, are identified in detailed sensitivity analyses. The development of conduit networks is examined in parameter studies, suggesting that the evolution of maze caves is predetermined by structural preferences such as laterally extended fissure networks beneath a horizon less prone to karstification. Without any structural preferences vertical shafts rather than maze caves are predicted to develop. The structure of the mature conduit system is found to be determined during early karstification, which is characterised by high hydraulic gradients and low flow rates in the gypsum layer. Short-term karst spring response after recharge events is firstly examined in parameter studies by forward modelling. The numerical simulations reveal that different controlling processes of heat and solute transport account for the different behaviour of water temperature and solute concentration frequently observed at karst springs. It is demonstrated that these differences may be employed to reduce the ambiguity in the aquifer characterisation. In order to test the feasibility of the corresponding inverse approach, which aims at inferring aquifer properties from the karst spring response, the model is applied to a field site in Southern Germany (Urenbrunnen spring, Vohringen). Data input is provided by both literature and own field work. Several models, which reproduce the results of a combined tracer and recharge test, are calibrated to spring discharges and solute concentrations measured after a recharge event. In order to validate the calibrated models, the measured spring water temperatures are simulated by heat transport modelling. The model application yields information on aquifer properties as well as flow and transport processes at the field site. Advection is identified as the dominant transport process, whereas the dissolution reaction of gypsum is found to be insignificant in this case. The application to gypsum aquifers demonstrates that both suggested approaches are suitable for the characterisation of karst systems. Model results, however, are highly sensitive to several input parameters, in particular in karst genesis modelling. Therefore, extensive field work is required to provide reliable data for site-specific model applications. In order to account for uncertainties, it is recommended to conduct parameter studies covering possible ranges of the most influential parameters.

Characterisation of karst systems by simulating aquifer genesis and spring responses: model development and application to gypsum karst, PhD thesis, 2002, Birk, S.

Karst aquifers are important groundwater resources, which are highly vulnerable to contamination due to fast transport in solutionally enlarged conduits. Management and protection of karst water resources require an adequate aquifer characterisation at the catchment scale. Due to the heterogeneity and complexity of karst systems, this is not easily achieved by standard investigation techniques such as pumping tests. Therefore, a process-based numerical modelling tool is developed, designed to support the karst aquifer characterisation using two complementary approaches: Firstly, the simulation of conduit enlargement, which aims at predicting aquifer properties by forward modelling of long-term karst genesis; secondly, the simulation of heat and solute transport processes, which aims at inferring aquifer properties from short-term karst spring response after recharge events.
Karst genesis modelling is applied to a conceptual setting based on field observations from the Western Ukraine, where the major part of known gypsum caves is found. Gypsum layers are typically supplied by artesian flow of aggressive water from insoluble aquifers underneath. Processes and parameters, controlling solutional enlargement of single conduits under artesian conditions, are identified in detailed sensitivity analyses. The development of conduit networks is examined in parameter studies, suggesting that the evolution of maze caves is predetermined by structural preferences such as laterally extended fissure networks beneath a horizon less prone to karstification. Without any structural preferences vertical shafts rather than maze caves are predicted to develop. The structure of the mature conduit system is found to be determined during early karstification, which is characterised by high hydraulic gradients and low flow rates in the gypsum layer.
Short-term karst spring response after recharge events is firstly examined in parameter studies by forward modelling. The numerical simulations reveal that different controlling processes of heat and solute transport account for the different behaviour of water temperature and solute concentration frequently observed at karst springs. It is demonstrated that these differences may be employed to reduce the ambiguity in the aquifer characterisation.
In order to test the feasibility of the corresponding inverse approach, which aims at inferring aquifer properties from the karst spring response, the model is applied to a field site in Southern Germany (Urenbrunnen spring, Vohringen). Data input is provided by both literature and own field work. Several models, which reproduce the results of a combined tracer and recharge test, are calibrated to spring discharges and solute concentrations measured after a recharge event. In order to validate the calibrated models, the measured spring water temperatures are simulated by heat transport modelling. The model application yields information on aquifer properties as well as flow and transport processes at the field site. Advection is identified as the dominant transport process, whereas the dissolution reaction of gypsum is found to be insignificant in this case.
The application to gypsum aquifers demonstrates that both suggested approaches are suitable for the characterisation of karst systems. Model results, however, are highly sensitive to several input parameters, in particular in karst genesis modelling. Therefore, extensive field work is required to provide reliable data for site-specific model applications. In order to account for uncertainties, it is recommended to conduct parameter studies covering possible ranges of the most influential parameters.


Hydraulic boundary conditions as a controlling factor in karst genesis: A numerical modeling study on artesian conduit development in gypsum., 2003, Birk S. , R. Liedl. , M. Sauter. , Teutsch G.
doi:10.1029/2002WR001308.A coupled continuum-pipe flow model is employed to simulate the development of karst conduits in an artesian setting, where aggressive water flows upward from an insoluble aquifer into a gypsum unit. Speleogenetic processes and controlling parameters are identified first for single conduit development. It is demonstrated that transient flow from the conduit into the surrounding fissured system of the rock enhances solutional conduit enlargement. Moreover, single conduit development is found to be highly sensitive to variations in initial diameter and hydraulic gradient. Simulating the solutional enlargement of pipe networks reveals that these two factors determine the resulting conduit pattern. Structural preferences are found to be essential for horizontal conduit development, otherwise flow paths are solely enlarged in vertical direction following the hydraulic gradient. Hydraulic gradients that increase with time can limit the extension or completely inhibit the development of horizontal caves even if lateral conduit development was structurally preferred.

Hydraulic boundary conditions as a controlling factor in karst genesis: A numerical modeling study on artesian conduit development in gypsum - art. no. 1004, 2003, Birk S, Liedl R, Sauter M, Teutsch G,
A coupled continuum-pipe flow model is employed to simulate the development of karst conduits in an artesian setting, where aggressive water flows upward from an insoluble aquifer into a gypsum unit. Speleogenetic processes and controlling parameters are identified first for single conduit development. It is demonstrated that transient flow from the conduit into the surrounding fissured system of the rock enhances solutional conduit enlargement. Moreover, single conduit development is found to be highly sensitive to variations in initial diameter and hydraulic gradient. Simulating the solutional enlargement of pipe networks reveals that these two factors determine the resulting conduit pattern. Structural preferences are found to be essential for horizontal conduit development, otherwise flow paths are solely enlarged in vertical direction following the hydraulic gradient. Hydraulic gradients that increase with time can limit the extension or completely inhibit the development of horizontal caves even if lateral conduit development was structurally preferred

Simulation of the development of karst aquifers using a coupled continuum pipe flow model - art. no. 1057, 2003, Liedl R. , Sauter M. , Huckinghaus D. , Clemens T. , Teutsch G. ,
[1] This paper is intended to provide insight into the controlling mechanisms of karst genesis based on an advanced modeling approach covering the characteristic hydraulics in karst systems, the dissolution kinetics, and the associated temporal decrease in flow resistance. Karst water hydraulics is strongly governed by the interaction between a highly conductive low storage conduit network and a low-conductive high-storage rock matrix under variable boundary conditions. Only if this coupling of flow mechanisms is considered can an appropriate representation of other relevant processes be achieved, e.g., carbonate dissolution, transport of dissolved solids, and limited groundwater recharge. Here a parameter study performed with the numerical model Carbonate Aquifer Void Evolution (CAVE) is presented, which allows the simulation of the genesis of karst aquifers during geologic time periods. CAVE integrates several important features relevant for different scenarios of karst evolution: (1) the complex hydraulic interplay between flow in the karst conduits and in the small fissures of the rock matrix, (2) laminar as well as turbulent flow conditions, (3) time-dependent and nonuniform recharge to both flow systems, (4) the widening of the conduits accounting for appropriate physicochemical relationships governing calcite dissolution kinetics. This is achieved by predefining an initial network of karst conduits ('protoconduits'') which are allowed to grow according to the amount of aggressive water available due to hydraulic boundary conditions. The increase in conduit transmissivity is associated with an increase in conduit diameters while the conductivity of the fissured system is assumed to be constant in time. The importance of various parameters controlling karst genesis is demonstrated in a parameter study covering the recharge distribution, the upgradient boundary conditions for the conduit system, and the hydraulic coupling between the conduit network and the rock matrix. In particular, it is shown that conduit diameters increase in downgradient or upgradient direction depending on the spatial distribution (local versus uniform) of the recharge component which directly enters the conduit system

An overview of the current research carried out in the French Western Alps karsts, 2004, Audra, Philippe

Current research encloses karst systems geomorphologic approach, recent advances in study of karst structures which date back from the Upper Miocene. Karst genesis in Western Alps is brought up by systemic analysis, according to a geomorphologic approach. It uses the "karst immunity" that conserves old drainage structures and their associated sediments. Karst landscapes can be sorted into horizontal and vertical forms. Speleothems are clearly connected to the presence of vegetation but they also record geomorphic crisis. Clastic sediments reveal mechanical erosion. This approach concludes with karst genesis and speleogenesis reconstruction, which blend together evolution stages, environment characterization and processes. Researchers reconsider the preponderant part previously attributed to glaciers. Karst appears immediately when a gradient exists and when the aquifer is stripped of its impervious cover. Such conditions occurred from the Upper Miocene and sometimes before. Karsts of the Pleistocene age are only met in the Inner Alps where cover stripping occurred later. Vertical systems composed of shaft series are old and become more complex. Field evidence refutes Ford's classification, which assigns a deep phreatic origin. A brief account of the present state of knowledge, according to region and researcher's scientific themes, allows establishing the last decade's advances. It also shows a disparity between the North and the South Western Alps, where Vercors appears to be one of the best studied massifs in the Alps.


Karst groundwater: a challenge for new resources, 2005, Bakalowicz M,
Karst aquifers have complex and original characteristics which make them very different from other aquifers: high heterogeneity created and organised by groundwater flow; large voids, high flow velocities up to several hundreds of m/h, high flow rate springs up to some tens of in 3/S. Different conceptual models, known from the literature, attempt to take into account all these particularities. The study methods used in classical hydrogeology-bore hole, pumping test and distributed models-are generally invalid and unsuccessful in karst aquifers, because the results cannot be extended to the whole aquifer nor to some parts, as is done in non-karst aquifers. Presently, karst hydrogeologists use a specific investigation methodology (described here), which is comparable to that used in surface hydrology. important points remain unsolved. Some of them are related to fundamental aspects such as the void structure only a conduit network, or a conduit network plus a porous matrix -, the functioning - threshold effects and nonlinearities -, the modeling of the functioning - double or triple porosity, or viscous flow in conduits - and of karst genesis. Some other points deal with practical aspects, such as the assessment of aquifer storage capacity or vulnerability, or the prediction of the location of highly productive zones

Modeling the influence of epikarst evolution on karst aquifer genesis: A time-variant recharge boundary condition for joint karst-epikarst development, 2005, Bauer S, Liedl R, Sauter M,
The epikarst, a zone of increased weathering near the land surface, determines the distribution of recharge to a karst aquifer in both space and time. It links climatic and near-surface geological conditions with the karstification of a limestone aquifer, defining both the hydraulic and the chemical boundary conditions for the development of the karst system. Realistic modeling of the epikarst is therefore a prerequisite for the simulation of karst aquifer genesis. A conceptual model of the joint karst-epikarst evolution is presented in this paper. An epikarst module is developed and implemented in a numerical continuum-discrete conduit flow model for karst genesis, which accounts for the joint evolution of the epikarst and the main karstic conduit network under unconfined conditions. The influence of epikarst genesis on the evolution of the underlying karst aquifer is investigated in four scenarios. It is found that only the interaction of epikarst and initial heterogeneity in the underlying carbonate rock leads to the development of a dendritic cave system. If no heterogeneity in the initial conduit network or in the recharge distribution is included, maze-type caves develop

Reactive transport modeling and hydrothermal karst genesis: The example of the Rocabruna barite deposit (Eastern Pyrenees), 2006, Corbella M, Ayora C, Cardellach E, Soler A,
In western Europe and North Africa, many sulfide and barite deposits appear to be related to the pre-Triassic paleosurface. Some of these mineralizations have traditionally been interpreted as the result of mineral fillings of previously formed karstic cavities. However, reactive transport modeling suggests that those minerals may have originated at depth and simultaneous with the cavity in the carbonate rocks. Numerical simulations using the Rocabruna deposit as an example recreate the genesis of such cavities and their filling by new minerals in a hydrothermal environment. Two warm (T = 150 [deg]C) fluids with different compositions but both saturated with dolomite were allowed to mix at a fracture intersection; the resulting solution strongly corroded the dolomite host rock and was able to create large voids in a hundred thousand year time scale. Our results show that equidimensional cavities originate from mixtures with equal fluxes of the contributing fluids, but elongated dissolution zones appear when the flux ratios were different from unity and the slowest flow direction coincided with the longest dimension of the void. Moreover, when the fluid mixture was dominated by a diluted and slightly alkaline groundwater instead of a 50-50 mixture with an acidic brine, dolomite dissolution or corrosion was more effective. Sulfide minerals precipitate around cavity walls replacing the host dolostone as the dolomite dissolution reaction couples with that of sulfide precipitation. This coupling produces some porosity, which is negligible compared to that caused by the mixing itself. Barite may also precipitate inside the forming cavity, but as the sulfate mineral precipitation reaction is not coupled with that of dolomite dissolution, barite grows in open space

Modle dvolution de paysages, application aux karsts en cockpit de Jamaque, 2007, Fleurant Cyril , Tucker Gregory, Viles Heather
LANDSCAPE EVOLUTION MODEL, EXAMPLE OF COCKPIT KARST TERRAINS, JAMAICA. A model of cockpit karst landscape evolution is presented. After explaining implementation of dissolution processes of limestone in the landscape evolution model CHILD, we develop a model of limestone denudation based on epikarst theory processes. The model takes into account an anisotropic dissolution in space and time according to what is observed in reality or described by scenarios of cockpit karst landscape evolution. This model requires a fractures network to take into account subsurface flow. Then, dissolution and thus fractures widening are computed and show a positive feedback between dissolution and flow. The relation between subcutaneous dissolution of fractures and denudation of the topography is introduced by means of an empirical equation associated with epikarst processes: the denudation is taken to be proportional to the dissolution in the subcutaneous zone. Simulated cockpit karst terrains are compared with real landscapes by means of morphometric criteria. Results of the model are very close to reality which hence confirms the importance of anisotropic dissolution processes and above all could be a numerical validation of the epikarst processes to describe cockpit karst genesis.

GEOMECHANICAL HYPOTHESIS OF KARST GENESIS, 2008,

The authors have founded a new hypothesis that relates various karsts’ genesis, including hydrothermal-karstic ore deposits, and evolution of rock masses in the areas of endogenous ring structures. The hypothesis is backed by the fact that karstic manifestations stick to the ring morpho-structures. The presented substantiation grows strong with the physical and numerical modeling of the kasrt formation mechanics and comparison of the modeling results and field data.


New Insight into Karst Genesis, 2010,

The paper sets forth a new hypothesis that connects karst origin with rock mass evolution in

the area of endogenous ring structures. The hypothesis is confirmed by correlation of karst

manifestations on the Earth’s surface with ring structures, by results of karst formation

physical and digital modelling and by resemblance of the modelling results and field

observation data


Volcanism-induced karst landforms and speleogenesis, in the Ankarana Plateau (Madagascar). Hypothesis and preliminary research., 2014,

The Ankarana is a limestone plateau in the northern part of Madagascar, where a cave system, more than 120 km long, has been explored. The plateau is bordered by volcanoes and is cut across by several canyons. An analysis of surface landforms and caves suggests that the karst genesis was probably initiated by volcanism beneath an impervious cover. Volcanic bulging and magma intrusions may have favored a basalt-limestone assimilation process and metamorphism. The ascent of deep volcanic fluids (CO2 and SO2) from magma degassing and from limestone metamorphism, may explain the speleogenesis. Once denuded, the karst evolved classically, but the selective erosion of metamorphosed rocks (more likely to be weathered than pure limestone), resulted in the creation of unusual landforms such as canyons and large circular basins.


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