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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 corrosion is 1. chemical action of water containing carbonic acid (also humidic, nitric, and other acids) on limestones and dolomites causing partial solution and related chemical changes in the rocks [20]. 2. erosion by solution or chemical action [10]. 3. the act or process of dissolving or wearing away metals [6]. see also accelerated corrosion; alluvial corrosion; corrasion; solution. compare aggressive water. synonyms: (french.) corrosion; (german.) korrosion; (greek.) chemeke thiavroses; (italian.) dissoluzione, corrosione; (russian.) korrozija; (spanish.) corrosion; (turkish.) eritme, yenme, kemirilme; (yugoslavian.) korozija.?

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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 stability (Keyword) returned 101 results for the whole karstbase:
Showing 76 to 90 of 101
Size matters: scalar phenomena and a proposal for an ecological definition of 'cave, 2008, Moseley, Max.
Caves, as ecological units, are redefined in terms of the ecologically-significant scalar phenomena that, in contrast with such traditional criteria as perpetual darkness, environmental stability and oligotrophy, are the special characteristics of large cavities (macrocaverns) in rocks. When so defined, 'caves' are ecologically distinct from the mesocaverns and all other subterranean habitats. Some implications of this perspective for the ecological classification of animals found in subterranean habitats are briefly discussed.

Flank Margin Cave Development in Telogenetic Limestones of New Zealand, 2008, Mylroie J. E. , Mylroie J. R. , Nelson C. S.

Coastal limestone outcrops, typically with advanced levels of diagenetic maturity (i.e., are telogenetic carbonates), were examined on North Island (Raglan Harbour, Kawhia Harbour, Napier, and Waipu Cove) and South Island (Pohara, Paturau River, Punakaiki, Kakanui, and Kaikoura), New Zealand, to determine if flank margin caves, produced by mixing dissolution, were present. In coastal settings, caves in carbonate rock can be the outcome of pseudokarst process, primarily wave erosion, as well as karst processes not associated with fresh and sea-water mixing such as epikarst features and conduit-flow stream caves. Flank margin caves were successfully differentiated from other cave types by the following criteria: phreatic dissolutional morphologies at the wall rock and chamber scales; absence of high- velocity, turbulent-flow wall sculpture and sediment deposits; and lack of integration of adjacent caves into a continuous flow path. The active tectonics of New Zealand creates a variable sea- level situation. The relatively short time of sea-level stability limits the size of the New Zealand flank margin caves compared to tectonically-stable environments, such as the Bahamas, where glacioeustasy alone controls sea-level stability. Uplift events can be identified as slow and steady when the flank margin caves are uniformly elongated in the vertical direction, and episodic when the flank margin caves show widening and tube development at discrete horizons that cut across rock structure. New Zealand flank margin caves contain information on uplift duration and rates independent of other commonly used measures, and therefore can provide a calibration to other methods.


Annual and transient signatures of gas exchange and transport in the Castaar de Ibor cave (Spain)., 2009, Fernandezcortes A. , Sanchezmoral S. , Cuezva S. , Caaveras J. C. And Abella R.
The large microclimatic stability is a basic characteristic of the subterranean karst systems and causes a high sensitivity to changes in environmental conditions. High-accuracy monitoring of Castaar de Ibor cave (Spain) determined the temporal evolution of the aerodynamic processes and ventilation rate by tracking CO2 and 222Rn levels over a twelve-month period. This cave is characterized by a very stable microclimate, with high and relatively constant radon content (the mean value is 32200 Bq/m3, roughly, and the standard deviation is 7600 Bq/m3) and a moderate and quite stable CO2 concentration (the mean value is 3730 ppm and the standard deviation is 250 ppm). Beside the general patterns of cave microclimate throughout an annual cycle, some particular microclimatic processes are described with regard to the gas exchange between the cave and the outside atmosphere. There is a complex microclimatic functional relationship between the meteorological and cave microclimate conditions and the diffusion and flow of tracer gases from the fractures and the pore system of soil and host rock to cave atmosphere. Transient variations of tracer gas on cave air are controlled by natural barometric fluxes and anthropogenic forced ventilation due to uncontrolled opening of cave entrance. The short-term fluctuations of gas levels on cave air reveal distinct patterns during the exhalation process of theses gases from the net of fissures and pores to the cave atmosphere, depending on the isolation effect of soil and host rock.

Annual and transient signatures of gas exchange and transport in the Castaar de Ibor cave (Spain), 2009, Fernandezcortes A. , Sanchezmoral S. , Cuezva S. , Caaveras J. C. , Abella R.

The large microclimatic stability is a basic characteristic of the subterranean karst systems and causes a high sensitivity to changes in environmental conditions. High-accuracy monitoring of Castañar de Ibor cave (Spain) determined the temporal evolution of the aerodynamic processes and ventilation rate by tracking CO2 and 222Rn levels over a twelve-month period. This cave is characterized by a very stable microclimate, with high and relatively constant radon content (the mean value is 32200 Bq/m3, roughly, and the standard deviation is 7600 Bq/m3) and a moderate and quite stable CO2 concentration (the mean value is 3730 ppm and the standard deviation is 250 ppm). Beside the general patterns of cave microclimate throughout an annual cycle, some particular microclimatic processes are described with regard to the gas exchange between the cave and the outside atmosphere. There is a complex microclimatic functional relationship between the meteorological and cave microclimate conditions and the diffusion and flow of tracer gases from the fractures and the pore system of soil and host rock to cave atmosphere. Transient variations of tracer gas on cave air are controlled by natural barometric fluxes and anthropogenic forced ventilation due to uncontrolled opening of cave entrance. The short-term fluctuations of gas levels on cave air reveal distinct patterns during the exhalation process of theses gases from the net of fissures and pores to the cave atmosphere, depending on the isolation effect of soil and host rock.


The initial stages of cave formation: Beyond the one-dimensional paradigm, 2011, Szymczak Piotr, Ladd Anthony J. C.

The solutional origin of limestone caves was recognized over a century ago, but the short penetration length of an undersaturated solution made it seem impossible for long conduits to develop. This is contradicted by field observations, where extended conduits, sometimes several kilometers long, are found in karst environments. However, a sharp drop in the dissolution rate of CaCO3 near saturation provides a mechanism for much deeper penetration of reactant. The notion of a “kinetic trigger” – a sudden change in rate constant over a narrow concentration range – has become a widely accepted paradigm in speleogenesis modeling. However, it is based on one-dimensional models for the fluid and solute transport inside the fracture, assuming that the dissolution front is planar in the direction perpendicular to the flow. Here we show that this assumption is incorrect; a planar dissolution front in an entirely uniform fracture is unstable to infinitesimal perturbations and inevitably breaks up into highly localized regions of dissolution. This provides an alternative mechanism for cave formation, even in the absence of a kinetic trigger. Our results suggest that there is an inherent wavelength to the erosion pattern in dissolving fractures, which depends on the reaction rate and flow rate, but is independent of the initial roughness. In contrast to one-dimensional models, two-dimensional simulations indicate that there is only a weak dependence of the breakthrough time on kinetic order; localization of the flow tends to keep the undersaturation in the dissolution front above the threshold for non-linear kinetics.

Research Highlights
- A kinetic trigger is not a prerequisite for limestone cave formation. - The added spatial dimension has a larger impact on breakthrough times than a kinetic trigger. - Planar dissolution front in a fracture is unstable to infinitesimal perturbations. - The most unstable wavelength depends on reaction kinetics and flow rate. - The instability leads to the formation of rapidly advancing, wormhole-like channels.


The use of karst geomorphology for planning, hazard avoidance and development in Great Britain, 2011, Cooper Anthony H. , Farrant Andrew R. , Price Simon J.

Within Great Britain five main types of karstic rocks – dolomite, limestone, chalk, gypsum and salt – are present. Each presents a different type and severity of karstic geohazard which are related to the rock solubility and geological setting. Typical karstic features associated with these rocks have been databased by the British Geological Survey (BGS) with records of sinkholes, cave entrances, stream sinks, resurgences and building damage; data for more than half of the country has been gathered. BGS has manipulated digital map data, for bedrock and superficial deposits, with digital elevation slope models, superficial deposit thickness models, the karst data and expertly interpreted areas, to generate a derived dataset assessing the likelihood of subsidence due to karst collapse. This dataset is informed and verified by the karst database and marketed as part of the BGS GeoSure suite. It is currently used by environmental regulators, the insurance and construction industries, and the BGS semi-automated enquiry system. The database and derived datasets can be further combined and manipulated using GIS to provide other datasets that deal with specific problems. Sustainable drainage systems, some of which use soak-aways into the ground, are being encouraged in Great Britain, but in karst areas they can cause ground stability problems. Similarly, open loop ground source heat or cooling pump systems may induce subsidence if installed in certain types of karstic environments such as in chalk with overlying sand deposits. Groundwater abstraction also has the potential to trigger subsidence in karst areas. GIS manipulation of the karst information is allowing Great Britain to be zoned into areas suitable, or unsuitable, for such uses; it has the potential to become part of a suite of planning management tools for local and National Government to assess the long term sustainable use of the ground.


A preliminary analysis of failure mechanisms in karst and man-made underground caves in Southern Italy, 2011, Parise M. , Lollino P.

Natural and anthropogenic caves may represent a potential hazard for the built environment, due to the occurrence of instability within caves, that may propagate upward and eventually reach the ground surface, inducing the occurrence of sinkholes. In particular, when caves are at shallow depth, the effects at the ground surface may be extremely severe. Apulia region (southern Italy) hosts many sites where hazard associated with sinkholes is very serious due to presence of both natural karst caves and anthropogenic cavities, the latter being mostly represented by underground quarries. The Pliocene–Pleistocene calcarenite (a typical soft rock) was extensively quarried underground, by digging long and complex networks of tunnels. With time, these underground activities have progressively been abandoned and their memory lost, so that many Apulian towns are nowadays located just above the caves, due to urban expansion in the last decades. Therefore, a remarkable risk exists for society, which should not be left uninvestigated.

The present contribution deals with the analysis of the most representative failure mechanisms observed in the field for such underground instability processes and the factors that seem to influence the processes, as for example those causing weathering of the rock and the consequent degradation of its physical and mechanical properties. Aimed at exploring the progression of instability of the cavities, numerical analyses have been developed by using both the finite element method for geological settings represented by continuous soft rock mass, and the distinct element method for jointed rock mass conditions. Both the effects of local instability processes occurring underground and the effects of the progressive enlargement of the caves on the overall stability of the rock mass have been investigated, along with the consequent failure mechanisms. In particular, degradation processes of the rock mass, as a consequence of wetting and weathering phenomena in the areas surrounding the caves, have been simulated. The results obtained from the numerical simulations have then been compared with what has been observed during field surveys and a satisfactory agreement between the numerical simulations and the instability processes, as detected in situ, has been noticed.


Minerogenetic mechanisms occurring in the cave environment: an overview, 2011, Onac Bogdan P. , Forti Paolo

Perhaps man’s first motivation to explore caves, beyond using them as shelter, was the search for substances that were not available elsewhere: most of them were minerals. However, for a long time it was believed that the cave environment was not very interesting from the mineralogical point of view. This was due to the fact that most cave deposits are normally composed of a single compound: calcium carbonate. Therefore, the systematic study of cave mineralogy is of only recent origin. However, although only a limited number of natural cavities have been investigated in detail, about 350 cave minerals have already been observed, some of which are new to science. The presence of such unexpected richness is a direct consequence of the variety of rocks traversed by water or other fluids before entering a cave and the sediments therein. Different cave environments allow the development of various minerogenetic mechanisms, the most important of which are double exchange reactions, evaporation, oxidation, hydration-dehydration, sublimation, deposition from aerosols and vapors, and segregation. The cave temperature and pH/Eh strictly control most of them, although some are driven by microorganisms. The cave environment, due to its long-term stability, can sometimes allow for the development of huge euhedral crystals, such as those found in the Naica caves (Mexico), but the presence of extremely small yet complex aggregates of different minerals is far more common. Future development in the field of cave mineralogy will likely be focused mainly on hydrothermal and sulfuric-acid caves and on the role played by micro-organisms in controlling some of the most important minerogenetic processes in caves


Karst, Uranium, Gold and Water Lessons from South Africa for Reconciling Mining Activities and Sustainable Water Use in Semi-arid Karst Areas: A Case Study, 2011, Winde, Frank

Despite the fact that much of the water stored in dams and reservoirs is lost to the atmosphere due to prevailing semi-arid conditions, South Africa traditionally relies mainly on surface water. Owing to an ever increasing demand that approaches the limits of economically exploitable surface water, the focus increasingly shifts towards groundwater as a long neglected resource. In this context, dolomitic karst aquifers that store large volumes of water protected from evaporation in vast underground cavities are of particular importance. This even more so as some of these aquifers are located in highly industrialised and densely populated areas such as the Gauteng Province, where water demand by far exceeds local supply and necessitates the expensive import of water from catchments as far as Lesotho. However, owing to impacts related to the century-old, deep-level gold mining that initiated South Africa’s economic development, many of the karst aquifers are currently not usable. Using the Far West Rand goldfield as an example, the extent, type and magnitude of mining-related impacts on dolomitic karst aquifers are analysed. This includes impacts on the geohydrological conditions in the area as well as water availability and ground stability associated with the large-scale dewatering of dolomitic aquifers that overly mine workings. Of particular concern is the mining-related contamination of groundwater and surface water with uranium which accompanies gold in most of the mined ore bodies. Finally, possible scenarios for water-related impacts of future mine closure are outlined and associated research needs identified. 


Structural and host rock controls on the distribution, morphology and mineralogy of speleothems in the Castanar Cave (Spain), 2011, Alonsozarza A. M. , Martinperez A. , Martingarcia R. , Gilpena I. , Melendez A. , Martinezflores E. , Hellstrom J. , Munozbarco P.

The Castanar Cave (central western Spain) formed in mixed carbonate-siliciclastic rocks of Neoproterozoic age. The host rock is finely bedded and shows a complex network of folds and fractures, with a prevalent N150E strike. This structure controlled the development and the maze pattern of the cave, as well as its main water routes. The cave formed more than 350 ka ago as the result of both the dissolution of interbedded carbonates and weathering of siliciclastic beds, which also promoted collapse of the overlying host rock. At present it is a totally vadose hypergenic cave, but its initial development could have been phreatic. The cave's speleothems vary widely in their morphology and mineralogy. In general, massive speleothems (stalactites, stalagmites, flowstones, etc.) are associated with the main fractures of the cave and bedding planes. These discontinuities offer a fairly continuous water supply. Other branching, fibrous, mostly aragonite speleothems, commonly occur in the steeper cave walls and were produced by capillary seepage or drip water. Detailed petrographical and isotope analyses indicate that both aragonite and calcite precipitated as primary minerals in the cave waters. Primary calcite precipitated in waters of low magnesium content, whereas aragonite precipitated from magnesium-rich waters. Differences in isotope values for calcite (-5.2‰ for ?18O and -9.6‰ for ?13C) and aragonite (?18O of -4.5‰ and ?13C of -3.5‰ ) can be explained by the fact that the more unstable mineral (aragonite) tends to incorporate the heavier C isotope to stabilize its structure or that aragonite precipitates in heavier waters. Changes in the water supply and the chemistry and instability of aragonite caused: (1) inversion of aragonite to calcite, which led to the transformation of aragonite needles into coarse calcite mosaics, (2) micritization, which appears as films or crusts of powdery, opaque calcite, and (3) dissolution. Dolomite, huntite, magnesite and sepiolite were identified within moonmilk deposits and crusts. Moonmilk occurs as a soft, white powder deposit on different types of speleothems, but mostly on aragonite formations. Huntite and magnesite formed as primary minerals, whereas dolomite arose via the replacement of both huntite and aragonite. Owing to its variety of speleothems and location in an area of scarce karstic features, the Castanar Cave was declared a Natural Monument in 1997 and is presently the target of a protection and research programme. Although the main products formed in the cave and their processes are relatively well known, further radiometric data are needed to better constrain the timing of these processes. For example, it is difficult to understand why some aragonite speleothems around 350 ka old have not yet given way to calcite, which indicates that the environmental setting of the cave is still not fully understood. 


Stability of dissolution flutes under turbulent flow, 2011, Hammer . , Lauritzen S. E. , Jamtveit B.

Dissolution of a solid surface under turbulent fluid flow can lead to the formation of periodic ripple-like structures with a wavelength dependent upon flow velocity. A model coupling hydrodynamics with mass transport and dissolution kinetics shows that the shape stability of these structures can be explained from fundamental
principles. The effects of a subgrid diffusion boundary layer must be included in the dissolution model to produce realistic results. The importance of including not only the mean flow velocity, but also the turbulent component of flow, in the dissolution model is emphasized. The numerical experiments also compare dissolution profiles for gypsum and calcite.


Temporal Stability of Cave Sediments, 2011, Peterson E. W. , Hughes K.

Sediments within cave systems have been examined concerning source, mineralogy, and transport potential. While sediments in the thalweg are very mobile, the entrainment potential of the sediment piles has not been examined. Over the course of nine months, sediment piles in a Missouri cave were sampled to determine the stability of the piles and of the sediment properties. Sediment cores were analyzed for dry bulk density (ρd), porosity (n), volumetric wetness (θ), organic content (O.C.), hydraulic conductivity (K), and sediment particle size distribution. Observational evidence, deposited sediment and deformation of previous sample holes, suggests that despite elevated flows, the sediment piles were not mobilized over the course of the nine months. Physical properties remained constant at each location, but varied among the various locations. Dry bulk density values ranged between 1.2 g/cm 3 to 1.5 g/cm 3 . Porosity values were 0.42 to 0.57. Volumetric wetness showed similar variation ranging from 0.38 to 0.53. Organic content had the highest variation among the parameters ranging from 1.24 percent at one site to 4.84 percent at another. Hydraulic conductivity ranged from 2.13×10 -7 m/s to 3.10×10 -7 m/s. 


Engineering Issues on Karst, 2011, Zhou Wanfang, Beck Barry F.

The design and construction of engineering structures in karst regions must deal with such challenges as difficulty in excavating and grading the ground over pinnacled rockheads, instability of ground surface, and unpredictable groundwater flow conditions. Detailed subsurface investigation using boring exploration, geophysical techniques, tracer testing, and groundwater monitoring helps optimize foundation designs and minimize uncertainties inherent in their construction. Based on the maturity of karst landscapes, depth and dimension of karst features, and vulnerability of groundwater contamination, methods that have been established to control surface water and groundwater and minimize sinkhole development include relocating structures to a safer site, filling voids/fractures with concrete, soil reinforcement, constructing deep foundations, and remediating sinkholes.


Höhlen der Schwäbischen Alb als Pegelschreiber für Flussgeschichte und Tektonik in Südwestdeutschland seit dem Miozän, 2011, Strasser Marcel

In south western Germany the karstified plateau of the Swabian Alb consisting of Upper Jurassic limestones hosts numerous caves, dolines, and dry valleys. Known strath terraces, conglomerates, volcanoes, and impact craters within the study area already provided important time stamps for former studies reconstructing landscape history. It is widely understood, that spatial distribution of most karst features is closely related to the palaeo-water-table and its discontinuous lowering over time, which in turn is the result of incision and/or uplift. The situation of the Swabian Alb at the northern rim of the Northern Alpine Foreland Basin and east of the Rhine Graben valley is the reason for this uplift. Many caves can be used as gauge for vertical displacement, considering horizontal cave passages as product of a stationary palaeowater-table and vertical sections as result of falling base level. In contrast recent studies deal with a different type of speleogenesis independent of base level. This hypogenic speleogenesis must be discussed for the caves of the Swabian Alb. The recently discovered cave named Laierhöhle near Geislingen/Steige is a typical 3d-maze providing several horizontal levels. Passage pattern and distinctive corrosion features match with morphologies (feeders, rising wall- and ceiling channels, outlets) characteristical for hypogenic speleogenesis. However, artesian situations, hydrothermal water or confined aquifers as critical conditions for hypogenic speleogenesis can not be verified. Other features like horizontal passages, water table markers, key-hole-features, and massive stratified sediment bodies are pointing to an epigenic, water-table related speleogenesis. In this study therefore a mixed model for speleogenesis of Laierhöhle is presented, assuming a strong initial deep-phreatic corrosion along fractures and fissures, followed by intensive widening at the palaeo water-table resulting in the formation of horizontal passages. Correlations between horizontal cave-levels, valley-bottoms, strath-terraces, local conglomerates and other caves lead to new and more precise data on the fluvial history, changing drainage pattern, and the uplift of parts of southwest Germany.

In the course of Examinations of cave sediments spherical metallic particles were detected. These magnetic spherules are ablation-products from meteorites during impact. After fallout and flushing into karstic voids and caves the spherules got archived till today. Spherules within Laierhöhle, Laichinger Tiefenhöhle and Mordloch are supposed to originate from the impact event producing the impact craters Steinheimer Becken and/or the Nördlinger Ries 14.59 Ma ago. Within most of the cave sediments spherules are accompanied by crystals of titano-magnetite, which built during volcanic activity of the Urach-Kirchheim volcanic field. Both spherules and titano-magnetites are proxies for re-deposited Mid Miocene Sediments. In this study I could correlate speleogenetic with dated geomorphic features and thus came to a chronology of events. The Laierhöhle records five episodes of long-term stability of the karst water table covering the time-span from late Middle Miocene until the Pliocene/Pleistocene transition. The first two stable episodes can be dated to the late Middle Miocene and Late Miocene (horizontal levels 1 and 2a). An episode responsible for the formation of level 2b falls within Early Pliocene time. Levels 3a and 3b are spatially well separated but must have formed within a relatively short timespan towards the end of the Pliocene. In the working area, total depth of penetrative karstification was in the order of 120 m. This penetration has been accomplished over a period of approximately 12 Ma resulting in an average uplift rate of 0.01 mm/a.


Multilevel Caves and Landscape Evolution, 2012, Anthony, Darlene M.

Multilevel caves are formed by periods of water table stability punctuated by changes in the position of the water table. These cave systems are hydrologically linked to regional rivers and can be used to date episodes of river stability and incision. The measurement of cosmogenic radioisotopes in cave sediments yields a burial age for the sediment, which in turn equates to the time of passage abandonment due to water-table lowering. Karst geomorphologists and others are using burial dates from multilevel caves to calculate Plio-Pleistocene rates of river incision, tectonic uplift, and erosion in various parts of the world.


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