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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 seep is 1. an area, generally small, where water or oil percolates slowly to the land surface. see seepage and spring [22]. 2. to move slowly through small openings of a porous material [22].?

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

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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;
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Your search for flows (Keyword) returned 315 results for the whole karstbase:
Showing 301 to 315 of 315
Rockmagnetic and palaeomagnetic studies of unconsolidated sediments of Bukovynka Cave ( Chernivtsi region, Ukraine), 2014, Bondar K. , Ridush B.

Rockmagnetic, palaeomagnetic, and paleontological studies of loamy non-consolidated sediments of the Bukovynka Cave (Chernivtsi region, Ukraine) have been carried out. The sections include three main types of deposits: 1 – fluvial deposits containing travertine grus derived from the karst massif, 2 – fluvial deposits derived from temporary waterflows from outside the cave, 3 – aeolian deposits. Deposits of type 2 and 3 were examined in Sections 1 and 2 in the Trapeznyi Chamber. Their low field magnetic susceptibility (χ) reflects climatic conditions in the Late Pleistocene. The layer with cave hyena bones has higher magnetic susceptibility and appeared to indicate warmer climate. Deposits of type 1 and 2 were investigated in the Section 3 in the Dry Chamber of the cave. Low-field magnetic susceptibility of fluvial deposits, derived from inside of the karst massif, is much higher than for deposits derived from outside the cave. Deposits in Section 3 sharply differ in χ, NRM intensity and Keonigsberger ratio. The fluvial strata of type 1 in Section 3, dated using paleontological remains as Holocene, contains the record of palaeosecular variations of the geomagnetic field. The Etrussia excursion dated 2.8 ka BP was found at 1 m depth in Section 3. The lowest layer has anomalous polarity.
 


Paleoflood events recorded by speleothems in caves, 2014, Gazquez F. , Calaforra J. M. , Forti P. , Stoll H. , Ghaleb B. , Delgadohuertas A.

Speleothems are usually composed of thin layers of calcite (or aragonite). However,
cemented detrital materials interlayered between laminae of speleothemic carbonate have been also observed in many caves. Flowstones comprising discontinuous carbonate layers form due to flowing water films,while flood events introduce fluviokarstic sediments in caves that, on occasion,are recorded as clayey layers inside flowstones and stalagmites. This record provides a potential means of understand­ing the frequency of palaeofloods using cave records.In this work,we investigate the origin of this type of detritaldeposit in El Soplao Cave (Northern Spain). The age of the lowest aragonite layer
of a flowstone reveals that the earliest flood period occurred before 500 ka, though most of the flowstone formed between 422 +69/-43 ka and 400 +66/-42 ka. This suggests that the cave was periodically affected by palaeoflood events that introduced detrital sediments from the surface as a result of occasional extreme rainfall events,especially at around 400 ka.The mineralogical data enable an evolutionary modelfor this flowstone to be generated based on the alternation offload events with laminar flows and carbonate layers precipitation that can be extrapolated to other caves in which detrital sediments inside speleothems have been found. 


Hydrological role of karst in the Chalk aquifer of Upper Normandy, France, 2014, Janyani S. El, Dupont J. P. , Massei N. , Slimani S. , Dörfliger N.

The role of karst on large-scale groundwater flow is defined for the Chalk aquifer of Upper Normandy (western Paris Basin), France. In the regional context, chalk plateaus occupy the greater part of watersheds and are the main sites of groundwater recharge. Previous studies focused on karstic output systems in the valleys and less on water-level variations in the recharge zones upstream. This study assesses the relevant hydrogeological processes using time-series data (boreholes and springs) recorded along a down-gradient hydrologeological cross-section in two selected watersheds. These hydrological data are interpreted in the framework of previous descriptions of the morphological organization of the study area’s karst network. The results highlight the hydrological role of (1) the input karst (vertical conduits) which drains recharging water, (2) the output karst (sub-horizontal conduits widely developed in the vicinity of valleys in the surface watersheds) which drains the output flows, and (3) the connections between these two (input and output) networks, which control the upstream water levels and allow quick transfer to springs, particularly after strong rainfall events. A conceptual model of the hydrological functioning of this covered karst aquifer is established, which should serve for the structuring and parameterization of a numerical model


Identification of the Exchange Coefficient from Indirect Data for a Coupled Continuum Pipe-Flow Model, 2014, Wu X. , Kugler Ph. , Lu Sh.

Calibration and identification of the exchange effect between the karst aquifers and the underlying conduit network are important issues in order to gain a better understanding of these hydraulic systems. Based on a coupled continuum pipe-flow (CCPF for short) model describing flows in karst aquifers, this paper is devoted to the identification of an exchange rate function, which models the hydraulic interaction between the fissured volume (matrix) and the conduit, from the Neumann boundary data, i.e., matrix/conduit seepage velocity. The authors formulate this parameter identification problem as a nonlinear operator equation and prove the compactness of the forward mapping. The stable approximate solution is obtained by two classic iterative regularization methods, namely, the Landweber iteration and Levenberg-Marquardt method. Numerical examples on noisefree and noisy data shed light on the appropriateness of the proposed approaches


The role of condensation in the evolution of dissolutional forms in gypsum caves: Study case in the karst of Sorbas (SE Spain), 2014, Gazquez F. , Calaforra J. M. , Forti P. , Waele J. D. , Sanna L.

The karst of Sorbas (SE Spain) is one of the most important gypsum areas worldwide. Its underground karst network comprises over 100 km of cave passages. Rounded smooth forms, condensation cupola and pendant-like features appear on the ceiling of the shallower passages as a result of gypsum dissolution by condensation water. Meanwhile, gypsum speleothems formed by capillarity, evaporation and aerosol deposition such as coralloids, gypsum crusts and rims are frequently observed closer to the passages floors. The role of condensation-dissolution mechanisms in the evolution of geomorphological features observed in the upper cave levels has been studied by means of long-term Micro-Erosion Meter (MEM) measurements, direct collection and analysis of condensation waters, and micrometeorological monitoring. Monitoring of erosion at different heights on gypsum walls of the Cueva del Agua reveals that the gypsum surface retreated up to 0.033 mm yr- 1 in MEM stations located in the higher parts of the cave walls. The surface retreat was negligible at the lowest sites, suggesting higher dissolution rates close to the cave ceiling, where warmer and moister air flows. Monitoring of microclimatic parameters and direct measurements of condensation water were performed in the Covadura Cave system in order to estimate seasonal patterns of condensation. Direct measurements of condensation water dripping from a metal plate placed in the central part of the El Bosque Gallery of Covadura Cave indicate that condensation takes place mainly between July and November in coincidence with rainless periods. The estimated gypsum surface lowering due to this condensation water is 0.0026 mm yr- 1. Microclimatic monitoring in the same area shows differences in air temperature and humidity of the lower parts of the galleries (colder and drier) with respect to the cave ceiling (warmer and wetter). This thermal sedimentation controls the intensity of the condensation-evaporation mechanisms at different heights in the cave.


Speleothem and biofilm formation in a granite/dolerite cave, Northern Sweden., 2014,

Tjuv-Antes grotta (Tjuv-Ante's Cave) located in northern Sweden is a round-abraded sea cave ('tunnel cave'), about 30 m in length, formed by rock-water abrasion in a dolerite dyke in granite gneiss. Abundant speleothems are restricted to the inner, mafic parts of the cave and absent on granite parts. The speleothems are of two types: cylindrical (coralloid, popcorn-like), and flowstone (thin crusts). Coralloids correspond to terrestrial stromatolite speleothems in which layers of light calcite alternate with dark, silica-rich laminae. The dark laminae are also enriched in carbon and contain incorporated remains of microorganisms. Two types of microbial communities can be distinguished associated with the speleothems: an Actinobacteria-like biofilm and a fungal community. Actinobacteria seem to play an important role in the formation of speleothem while the fungal community acts as both a constructive and a destructive agent. A modern biofilm dominated by Actinobacteria is present in the speleothem-free parts of the dolerite and located in cave ceiling cracks. These biofilms may represent sites of early speleothem formation. Because of its unusual position in between two types of host rock, Tjuv-Ante's Cave represents a unique environment in which to study differences in microbe-rock interactions and speleothem genesis between the granite and dolerite host rock. Our study shows that the mafic rock is superior to the granite in hosting a microbial community and to support formation of speleothems.


Incipient vertical traction carpets within collapsed sinkhole fills, 2014,

Small vertically oriented traction carpets are reported from the collapsed sandy fills of 100 m deep Devonian limestone sinkholes underlying the Lower Cretaceous Athabasca oil sands deposit in north-eastern Alberta, Western Canada. Dissolution of 100 m of underlying halite salt beds caused cataclysmic collapse of the sinkhole floors and water saturated sinkhole sand fills to descend very rapidly. Turbulent currents flushed upper sinkhole fills of friable sandstone blocks and disaggregated sand and quartz pebble for tens of metres. Laminar deposits with inverse grading accumulated as many as six to eight curvilinear entrained pebble streaks, 10 to 30 cm long, vertically impinged against the sides of descending collapse blocks. These deposits were initiated as vertically oriented early stage traction carpets that interlocked fine sand grains and inversely graded overlying pebbles entrained below the dilute overlying turbulent flows. Vortexes that flushed these sinkhole fills and induced these depositional processes may have lasted only seconds before the very rapid descents abruptly halted. Some of the fabrics were suspended vertically in-place and preserved from unlocking and obliteration. These small fabrics provide insight into the instability and ephemeral character of the transition from strong gravity-driven grain falls to very early stages of traction carpet formation. These short-lived deposits of very thin sand layers resulted from sufficient incipient frictional freezing that grain interlocking overcame, however briefly, the strong gravity drives of the vertical falls that would have otherwise dispersed grains and obliterated any organized fabric patterns. Tenuous frictionally locked grains were also suspended at the centres of hyperbolic grain fall flows that briefly developed between turbulent flow eddies, some of which were fortuitously preserved. Some of these suspended grain locking zones passed downward onto the relatively more stable surfaces of the rapidly descending block surfaces. The morphogenesis of these early stage traction carpets differ from more fully developed deposits elsewhere because of their short-lived transport, dynamic instability and vertical orientation.


Hydrogeology of northern Sierra de Chiapas, Mexico: A conceptual model based on a geochemical characterization of sulfide-rich karst brackish springs, 2014,

Conspicuous sulfide-rich karst springs flow from Cretaceous carbonates in northern Sierra de Chiapas, Mexico. This is a geologically complex, tropical karst area. The physical, geologic, hydrologic and chemical attributes of these springs were determined and integrated into a conceptual hydrogeologic model. A meteoric source and a recharge elevation below 1500 m are estimated from the spring water isotopic signature regardless of their chemical composition. Brackish spring water flows at a maximum depth of 2000 m, as inferred from similar chemical attributes to the produced water from a nearby oil well. Oil reservoirs may be found at depths below 2000 m. Three subsurface environments or aquifers are identified based on the B, Li+, K+ and SiO2 concentrations, spring water temperatures, and CO2 pressures. There is mixing between these aquifers. The aquifer designated Local is shallow and contains potable water vulnerable to pollution. The aquifer named Northern receives some brackish produced water. The composition of the Southern aquifer is influenced by halite dissolution enhanced at fault detachment surfaces. Epigenic speleogenesis is associated with the Local springs. In contrast, hypogenic speleogenesis is associated with the brackish sulfidic springs from the Northern and the Southern environments.


The role of condensation in the evolution of dissolutional forms in gypsum caves: Study case in the karst of Sorbas (SE Spain), 2015, Gazquez Fernando, Calaforra José Maria, Forti Paolo, De Waele Jo, Sanna Laura

The karst of Sorbas (SE Spain) is one of the most important gypsum areas worldwide. Its underground karst network comprises over 100 km of cave passages. Rounded smooth forms, condensation cupola and pendant-like features appear on the ceiling of the shallower passages as a result of gypsum dissolution by condensation water. Meanwhile, gypsum speleothems formed by capillarity, evaporation and aerosol deposition such as coralloids, gypsum crusts and rims are frequently observed closer to the passage floors. The role of condensation–dissolution mechanisms in the evolution of geomorphological features observed in the upper cave levels has been studied by means of long-term micro-erosion meter (MEM) measurements, direct collection and analysis of condensation waters, and micrometeorological monitoring. Monitoring of erosion at different heights on gypsum walls of the Cueva del Agua reveals that the gypsum surface retreated up to 0.033 mm yr−1 in MEM stations located in the higher parts of the cave walls. The surface retreat was negligible at the lowest sites, suggesting higher dissolution rates close to the cave ceiling, where warmer and moister air flows. Monitoring of microclimatic parameters and direct measurements of condensation water were performed in the Covadura Cave system in order to estimate seasonal patterns of condensation. Direct measurements of condensation water dripping from a metal plate placed in the central part of the El Bosque Gallery of Covadura Cave indicate that condensation takes place mainly between July and November in coincidence with rainless periods. The estimated gypsum surface lowering due to this condensation water is 0.0026 mm yr−1. Microclimatic monitoring in the same area shows differences in air temperature and humidity of the lower parts of the galleries (colder and drier) with respect to the cave ceiling (warmer and wetter). This thermal sedimentation controls the intensity of the condensation–evaporation mechanisms at different heights in the cave.


Long-term erosion rate measurements in gypsum caves of Sorbas (SE Spain) by the Micro-Erosion Meter method, 2015, Sanna Laura, De Waele Jo, Calaforra José Maria, Forti Paolo

The present work deals with the results of long-term micro-erosion measurements in the most important gypsum cave of Spain, the Cueva del Agua (Sorbas, Almeria, SE Spain). Nineteen MEM stations were positioned in 1992 in a wide range of morphological and environmental settings (gypsum floors and walls, carbonate speleothems, dry conduits and vadose passages) inside and outside the cave, on gypsum and carbonate bedrocks and exposed to variable degree of humidity, different air flowand hydrodynamic conditions. Four different sets of stations have been investigated: (1) the main cave entrance (Las Viñicas spring); (2) the main river passage; (3) the abandoned Laboratory tunnel; and (4) the external gypsum surface. Data over a period of about 18 years are available. The average lowering rates vary from 0.014 to 0.016 mm yr−1 near the main entrance and in the Laboratory tunnel, to 0.022 mm −1 on gypsum floors and 0.028 mm yr−1 on carbonate flowstones. 

The denudation data from the external gypsum stations are quite regular with a rate of 0.170 mm yr−1. The observations allowed the collecting of important information concerning the feeding of the karst aquifer not only by infiltrating rainwater, but under present climate conditions also by water condensation of moist air flow. This contribution to the overall karst processes in the Cueva del Agua basin represents over 20% of the total chemical dissolution of the karst area and more than 50% of the speleogenetically removed gypsum in the cave system, thus representing all but a secondary role in speleogenesis. Condensation–corrosion is most active along the medium walls, being slower at the roof and almost absent close to the floor. This creates typical corrosion morphologies such as cupola, while gypsum flowers develop where evaporation dominates. This approach also shows quantitatively the morphological implications of condensation–corrosion processes in gypsum karst systems in arid zones, responsible for an average surface lowering of 0.047 mm yr−1, while mechanical erosion produces a lowering of 0.123 mm yr−1.


Research frontiers in speleogenesis. Dominant processes, hydrogeological conditions and resulting cave patterns, 2015,

Speleogenesis is the development of well-organized cave systems by fluids moving through fissures of a soluble rock. Epigenic caves induced by biogenic CO2 soil production are dominant, whereas hypogenic caves resulting from uprising deep flow not directly connected to adjacent recharge areas appear to be more frequent than previously considered. The conceptual models of epigenic cave development moved from early models, through the “four-states model” involving fracture influence to explain deep loops, to the digital models demonstrating the adjustment of the main flow to the water table. The relationships with base level are complex and cave levels must be determined from the elevation of the vadose-phreatic transitions. Since flooding in the epiphreatic zone may be important, the top of the loops in the epiphreatic zone can be found significantly high above the base level. The term Paragenesis is used to describe the upward development of conduits as their lower parts fill with sediments. This process often records a general baselevel rise. Sediment influx is responsible for the regulation of long profiles by paragenesis and contributes to the evolution of profiles from looping to water table caves. Dating methods allow identification of the timing of cave level evolution. The term Ghost-rock karstification is used to describe a 2-phase process of speleogenesis, with a first phase of partial solution of rock along fractures in low gradient conditions leaving a porous matrix, the ghost-rock, then a second phase of mechanical removing of the ghost-rock mainly by turbulent flow in high gradient conditions opening the passages and forming maze caves. The first weathering phase can be related either to epigenic infiltration or to hypogenic upflow, especially in marginal areas of sedimentary basins. The vertical pattern of epigenic caves is mainly controlled by timing, geological structure, types of flow and base-level changes. We define several cave types as (1) juvenile, where they are perched above underlying aquicludes; (2) looping, where recharge varies greatly with time, to produce epiphreatic loops; (3) water-table caves where flow is regulated by a semi-pervious cover; and (4) caves in the equilibrium stage where flow is transmitted without significant flooding. Successive base-level drops caused by valley entrenchment make cave levels, whereas baselevel rise is defined in the frame of the Per ascensum Model of Speleogenesis (PAMS), where deep passages are flooded and drain through vauclusian springs. The PAMS can be active after any type of baselevel rise (transgression, fluvial aggradation, tectonic subsidence) and explains most of the deep phreatic cave systems except for hypogenic.

The term Hypogenic speleogenesis is used to describe cave development by deep upflow independent of adjacent recharge areas. Due to its deep origin, water frequently has a high CO2-H2S concentration and a thermal anomaly, but not systemati­cally. Numerous dissolution processes can be involved in hypogenic speleogenesis, which often include deep-seated acidic sources of CO2 and H2S, “hydrothermal” cooling, mixing corrosion, Sulfuric Acid Speleogenesis (SAS), etc. SAS particularly involves the condensation-corrosion processes, resulting in the fast expansion of caves above the water table, i.e. in an atmo­spheric environment. The hydrogeological setting of hypogenic speleogenesis is based on the Regional Gravity Flow concept, which shows at the basin scales the sites of convergences and upflows where dissolution focuses. Each part of a basin (mar­ginal, internal, deep zone) has specific conditions. The coastal basin is a sub-type. In deformed strata, flow is more complex according to the geological structure. However, upflow and hypogenic speleogenesis concentrate in structural highs (buried anticlines) and zones of major disruption (faults, overthrusts). In disrupted basins, the geothermal gradient “pumps” the me­teoric water at depth, making loops of different depths and characteristics. Volcanism and magmatism also produce deep hypogenic loops with “hyperkarst” characteristics due to a combination of deep-seated CO2, H2S, thermalism, and microbial activity. In phreatic conditions, the resulting cave patterns

can include geodes, 2–3D caves, and giant ascending shafts. Along the water table, SAS with thermal air convection induces powerful condensation-corrosion and the development of upwardly dendritic caves, isolated chambers, water table sulfuricacid caves. In the vadose zone, “smoking” shafts evolve under the influence of geothermal gradients producing air convectionand condensation-corrosion.

Likely future directions for research will probably involve analytical and modeling methods, especially using isotopes, dating, chemical simulations, and field investigations focused on the relationships between processes and resulting morphologies.


Research frontiers in speleogenesis. Dominant processes, hydrogeological conditions and resulting cave patterns, 2015,

Speleogenesis is the development of well-organized cave systems by fluids moving through fissures of a soluble rock. Epigenic caves induced by biogenic CO2 soil production are dominant, whereas hypogenic caves resulting from uprising deep flow not directly connected to adjacent recharge areas appear to be more frequent than previously considered. The conceptual models of epigenic cave development moved from early models, through the “four-states model” involving fracture influence to explain deep loops, to the digital models demonstrating the adjustment of the main flow to the water table. The relationships with base level are complex and cave levels must be determined from the elevation of the vadose-phreatic transitions. Since flooding in the epiphreatic zone may be important, the top of the loops in the epiphreatic zone can be found significantly high above the base level. The term Paragenesis is used to describe the upward development of conduits as their lower parts fill with sediments. This process often records a general baselevel rise. Sediment influx is responsible for the regulation of long profiles by paragenesis and contributes to the evolution of profiles from looping to water table caves. Dating methods allow identification of the timing of cave level evolution. The term Ghost-rock karstification is used to describe a 2-phase process of speleogenesis, with a first phase of partial solution of rock along fractures in low gradient conditions leaving a porous matrix, the ghost-rock, then a second phase of mechanical removing of the ghost-rock mainly by turbulent flow in high gradient conditions opening the passages and forming maze caves. The first weathering phase can be related either to epigenic infiltration or to hypogenic upflow, especially in marginal areas of sedimentary basins. The vertical pattern of epigenic caves is mainly controlled by timing, geological structure, types of flow and base-level changes. We define several cave types as (1) juvenile, where they are perched above underlying aquicludes; (2) looping, where recharge varies greatly with time, to produce epiphreatic loops; (3) water-table caves where flow is regulated by a semi-pervious cover; and (4) caves in the equilibrium stage where flow is transmitted without significant flooding. Successive base-level drops caused by valley entrenchment make cave levels, whereas baselevel rise is defined in the frame of the Per ascensum Model of Speleogenesis (PAMS), where deep passages are flooded and drain through vauclusian springs. The PAMS can be active after any type of baselevel rise (transgression, fluvial aggradation, tectonic subsidence) and explains most of the deep phreatic cave systems except for hypogenic.

The term Hypogenic speleogenesis is used to describe cave development by deep upflow independent of adjacent recharge areas. Due to its deep origin, water frequently has a high CO2-H2S concentration and a thermal anomaly, but not systemati­cally. Numerous dissolution processes can be involved in hypogenic speleogenesis, which often include deep-seated acidic sources of CO2 and H2S, “hydrothermal” cooling, mixing corrosion, Sulfuric Acid Speleogenesis (SAS), etc. SAS particularly involves the condensation-corrosion processes, resulting in the fast expansion of caves above the water table, i.e. in an atmo­spheric environment. The hydrogeological setting of hypogenic speleogenesis is based on the Regional Gravity Flow concept, which shows at the basin scales the sites of convergences and upflows where dissolution focuses. Each part of a basin (mar­ginal, internal, deep zone) has specific conditions. The coastal basin is a sub-type. In deformed strata, flow is more complex according to the geological structure. However, upflow and hypogenic speleogenesis concentrate in structural highs (buried anticlines) and zones of major disruption (faults, overthrusts). In disrupted basins, the geothermal gradient “pumps” the me­teoric water at depth, making loops of different depths and characteristics. Volcanism and magmatism also produce deep hypogenic loops with “hyperkarst” characteristics due to a combination of deep-seated CO2, H2S, thermalism, and microbial activity. In phreatic conditions, the resulting cave patterns

can include geodes, 2–3D caves, and giant ascending shafts. Along the water table, SAS with thermal air convection induces powerful condensation-corrosion and the development of upwardly dendritic caves, isolated chambers, water table sulfuricacid caves. In the vadose zone, “smoking” shafts evolve under the influence of geothermal gradients producing air convectionand condensation-corrosion.

Likely future directions for research will probably involve analytical and modeling methods, especially using isotopes, dating, chemical simulations, and field investigations focused on the relationships between processes and resulting morphologies.


Research frontiers in speleogenesis. Dominant processes, hydrogeological conditions and resulting cave patterns, 2015,

Speleogenesis is the development of well-organized cave systems by fluids moving through fissures of a soluble rock. Epigenic caves induced by biogenic CO2 soil production are dominant, whereas hypogenic caves resulting from uprising deep flow not directly connected to adjacent recharge areas appear to be more frequent than previously considered. The conceptual models of epigenic cave development moved from early models, through the “four-states model” involving fracture influence to explain deep loops, to the digital models demonstrating the adjustment of the main flow to the water table. The relationships with base level are complex and cave levels must be determined from the elevation of the vadose-phreatic transitions. Since flooding in the epiphreatic zone may be important, the top of the loops in the epiphreatic zone can be found significantly high above the base level. The term Paragenesis is used to describe the upward development of conduits as their lower parts fill with sediments. This process often records a general baselevel rise. Sediment influx is responsible for the regulation of long profiles by paragenesis and contributes to the evolution of profiles from looping to water table caves. Dating methods allow identification of the timing of cave level evolution. The term Ghost-rock karstification is used to describe a 2-phase process of speleogenesis, with a first phase of partial solution of rock along fractures in low gradient conditions leaving a porous matrix, the ghost-rock, then a second phase of mechanical removing of the ghost-rock mainly by turbulent flow in high gradient conditions opening the passages and forming maze caves. The first weathering phase can be related either to epigenic infiltration or to hypogenic upflow, especially in marginal areas of sedimentary basins. The vertical pattern of epigenic caves is mainly controlled by timing, geological structure, types of flow and base-level changes. We define several cave types as (1) juvenile, where they are perched above underlying aquicludes; (2) looping, where recharge varies greatly with time, to produce epiphreatic loops; (3) water-table caves where flow is regulated by a semi-pervious cover; and (4) caves in the equilibrium stage where flow is transmitted without significant flooding. Successive base-level drops caused by valley entrenchment make cave levels, whereas baselevel rise is defined in the frame of the Per ascensum Model of Speleogenesis (PAMS), where deep passages are flooded and drain through vauclusian springs. The PAMS can be active after any type of baselevel rise (transgression, fluvial aggradation, tectonic subsidence) and explains most of the deep phreatic cave systems except for hypogenic.

The term Hypogenic speleogenesis is used to describe cave development by deep upflow independent of adjacent recharge areas. Due to its deep origin, water frequently has a high CO2-H2S concentration and a thermal anomaly, but not systemati­cally. Numerous dissolution processes can be involved in hypogenic speleogenesis, which often include deep-seated acidic sources of CO2 and H2S, “hydrothermal” cooling, mixing corrosion, Sulfuric Acid Speleogenesis (SAS), etc. SAS particularly involves the condensation-corrosion processes, resulting in the fast expansion of caves above the water table, i.e. in an atmo­spheric environment. The hydrogeological setting of hypogenic speleogenesis is based on the Regional Gravity Flow concept, which shows at the basin scales the sites of convergences and upflows where dissolution focuses. Each part of a basin (mar­ginal, internal, deep zone) has specific conditions. The coastal basin is a sub-type. In deformed strata, flow is more complex according to the geological structure. However, upflow and hypogenic speleogenesis concentrate in structural highs (buried anticlines) and zones of major disruption (faults, overthrusts). In disrupted basins, the geothermal gradient “pumps” the me­teoric water at depth, making loops of different depths and characteristics. Volcanism and magmatism also produce deep hypogenic loops with “hyperkarst” characteristics due to a combination of deep-seated CO2, H2S, thermalism, and microbial activity. In phreatic conditions, the resulting cave patterns

can include geodes, 2–3D caves, and giant ascending shafts. Along the water table, SAS with thermal air convection induces powerful condensation-corrosion and the development of upwardly dendritic caves, isolated chambers, water table sulfuricacid caves. In the vadose zone, “smoking” shafts evolve under the influence of geothermal gradients producing air convectionand condensation-corrosion.

Likely future directions for research will probably involve analytical and modeling methods, especially using isotopes, dating, chemical simulations, and field investigations focused on the relationships between processes and resulting morphologies.


Research frontiers in speleogenesis. Dominant processes, hydrogeological conditions and resulting cave patterns, 2015,

Speleogenesis is the development of well-organized cave systems by fluids moving through fissures of a soluble rock. Epigenic caves induced by biogenic CO2 soil production are dominant, whereas hypogenic caves resulting from uprising deep flow not directly connected to adjacent recharge areas appear to be more frequent than previously considered. The conceptual models of epigenic cave development moved from early models, through the “four-states model” involving fracture influence to explain deep loops, to the digital models demonstrating the adjustment of the main flow to the water table. The relationships with base level are complex and cave levels must be determined from the elevation of the vadose-phreatic transitions. Since flooding in the epiphreatic zone may be important, the top of the loops in the epiphreatic zone can be found significantly high above the base level. The term Paragenesis is used to describe the upward development of conduits as their lower parts fill with sediments. This process often records a general baselevel rise. Sediment influx is responsible for the regulation of long profiles by paragenesis and contributes to the evolution of profiles from looping to water table caves. Dating methods allow identification of the timing of cave level evolution. The term Ghost-rock karstification is used to describe a 2-phase process of speleogenesis, with a first phase of partial solution of rock along fractures in low gradient conditions leaving a porous matrix, the ghost-rock, then a second phase of mechanical removing of the ghost-rock mainly by turbulent flow in high gradient conditions opening the passages and forming maze caves. The first weathering phase can be related either to epigenic infiltration or to hypogenic upflow, especially in marginal areas of sedimentary basins. The vertical pattern of epigenic caves is mainly controlled by timing, geological structure, types of flow and base-level changes. We define several cave types as (1) juvenile, where they are perched above underlying aquicludes; (2) looping, where recharge varies greatly with time, to produce epiphreatic loops; (3) water-table caves where flow is regulated by a semi-pervious cover; and (4) caves in the equilibrium stage where flow is transmitted without significant flooding. Successive base-level drops caused by valley entrenchment make cave levels, whereas baselevel rise is defined in the frame of the Per ascensum Model of Speleogenesis (PAMS), where deep passages are flooded and drain through vauclusian springs. The PAMS can be active after any type of baselevel rise (transgression, fluvial aggradation, tectonic subsidence) and explains most of the deep phreatic cave systems except for hypogenic.

The term Hypogenic speleogenesis is used to describe cave development by deep upflow independent of adjacent recharge areas. Due to its deep origin, water frequently has a high CO2-H2S concentration and a thermal anomaly, but not systemati­cally. Numerous dissolution processes can be involved in hypogenic speleogenesis, which often include deep-seated acidic sources of CO2 and H2S, “hydrothermal” cooling, mixing corrosion, Sulfuric Acid Speleogenesis (SAS), etc. SAS particularly involves the condensation-corrosion processes, resulting in the fast expansion of caves above the water table, i.e. in an atmo­spheric environment. The hydrogeological setting of hypogenic speleogenesis is based on the Regional Gravity Flow concept, which shows at the basin scales the sites of convergences and upflows where dissolution focuses. Each part of a basin (mar­ginal, internal, deep zone) has specific conditions. The coastal basin is a sub-type. In deformed strata, flow is more complex according to the geological structure. However, upflow and hypogenic speleogenesis concentrate in structural highs (buried anticlines) and zones of major disruption (faults, overthrusts). In disrupted basins, the geothermal gradient “pumps” the me­teoric water at depth, making loops of different depths and characteristics. Volcanism and magmatism also produce deep hypogenic loops with “hyperkarst” characteristics due to a combination of deep-seated CO2, H2S, thermalism, and microbial activity. In phreatic conditions, the resulting cave patterns

can include geodes, 2–3D caves, and giant ascending shafts. Along the water table, SAS with thermal air convection induces powerful condensation-corrosion and the development of upwardly dendritic caves, isolated chambers, water table sulfuricacid caves. In the vadose zone, “smoking” shafts evolve under the influence of geothermal gradients producing air convectionand condensation-corrosion.

Likely future directions for research will probably involve analytical and modeling methods, especially using isotopes, dating, chemical simulations, and field investigations focused on the relationships between processes and resulting morphologies.


Engineering challenges in Karst, 2015,

Anisotropy and heterogeneity of karstified rocks make them the most problematic media for various interventions which are needed in engineering practice. The long history of attempts to adapt karstic nature to human needs started with the utilization of karstic aquifers: tapping large springs, transferring their waters to the long distances, improving minimal flows or capturing fresh water in coastal areas. During the 20th century the number of other challenges such as building dam and reservoirs, and constructing roads and railways, bridges, tunnels, new settlements open a new era in engineering works but also in collecting new knowledge and experience for the karstology and hydrogeology sciences. Today, almost no engineering projects can be implemented without a proper environmental impact assessment, which establishes a better balance between human and ecological needs. 


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