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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 hygrometer is 1. an instrument that reads the humidity in the air directly; some are based on a hair's ability to shrink or expand with humidity, or on certain electronic chips. generally, a psychrometer is more accurate at higher humidities (above 95%) [23]. 2. apparatus for the direct measurement of the relative humidity in the atmosphere [16]. see also psychrometer.?

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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 landscape evolution (Keyword) returned 50 results for the whole karstbase:
Showing 16 to 30 of 50
Cave Genesis and its relationship to surface processes: investigations in the Siebenhengste region (BE, Switzerland), PhD Thesis, 2002, Haeuselmann, Ph.

This PhD thesis deals with the speleogenesis of the youngest six phases in the Siebenhengste system (Switzerland). A speleogenetic model is developed, linking the four-state-model with the model of Audra (1994), taking into account the speleogenetic processes in the flooding zone. The refinement of the speleogenetic phases allowed to reconstruct the valley deepening processes in the late Quarternary. Moreover, an idea about the landscape evolution since the Mio-Pliocene is sketched. U/Th datings allowed the timing of the last four speleogenetic phases as well as glacial advances and retreats during the last 400'000 years, thus considerably enhancing the continental Quarternary record. With information from Baerenschacht and St. Beatus Cave, the tectonic history and the geometry of the folds could be retraced. A comprehensive analysis of all dye tracing experiments is given. 

Karst landscape evolution, 2003, Kaufmann, G.

We present results of a numerical study of karst denudation on limestone plateaux. The landscape evolution model used incorporates not only long-range fluvial processes and short-range hill-slope processes, but also large-scale chemical dissolution of limestone surfaces. The relative efficiencies of fluvial and chemical processes are of equal importance to the landscape evolution of a plateau dropping to sea level along an escarpment. While fluvial processes have an impact confined to river channels, the karst denudation process is more uniform, removing material also from the plateau surface. The combined effect of both processes results in a landscape evolution almost twice as effective as the purely erosional evolution of an insoluble landscape.

'Canons' revisited and reviewed: Lester King's views of landscape evolution considered 50 years later, 2003, Twidale C. R. ,
Fifty years after its publication, Lester King's Canons of Landscape Evolution is reviewed and is considered in light of subsequent trends and actual developments. Some of his ideas, such as the role of scarp recession and the antiquity of some surfaces, remain current. His broad view of the world and his interest in major relief anticipated trends that are now fashionable. Some of his interpretations, however, and in particular his downgrading of the importance of structural factors and his linking of scarp retreat and pedimentation, have not stood the test of time. Other concepts, such as the etch or two-stage origin of forms, which were mooted but not fully appreciated in King's day, have come to the forefront, and technological advances in dating and survey, particularly of the ocean floors, have signaled new perspectives in landscape interpretation. Nevertheless, King's was a courageous attempt to provide guidelines for landscape study

Landscape Evolution and Cave Development in Response to Episodic Incision of the Cumberland River, Tennessee and Kentucky, USA., 2003, Anthony, Darlene M. Ph. D.

Episodic incision punctuated by periods of base level stability during the Plio-Pleistocene left the Upper Cumberland River in Tennessee and Kentucky deeply entrenched into the unglaciated Appalachian Plateaus. The relative chronology of episodic river incision and base level stability is well documented thanks to over a century of careful mapping of upland surfaces, inset straths, and terrace gravels. Constraining the timing of these incision events has been difficult, however, primarily due to a lack of suitable dating methods for terrace materials ranging from several hundred thousand to several million years of age, and reworking of upland gravels onto lower terraces. These problems are solved by dating the burial age of undisturbed cave sediments in place of terrace deposits, using the differential decay of cosmogenic 26Al and 10Be in quartz exposed to cosmic radiation at the surface. This study offers a new chronology of river incision beginning with initial incision into the Highland Rim after ~3.5 Ma; development of the Parker strath between ~3.5 and ~2 Ma; incision of the Parker strath at ~2 Ma; development of a major terrace beneath the Parker strath between ~2 and ~1.5 Ma; incision into this terrace at ~1.3 Ma; and the development of several discontinuous terraces above the modern flood plain between ~1.3 Ma and the present.
Large caves on tributaries of the Upper Cumberland River record a headward wave of incision in the Pliocene and Early Pleistocene. The passage of a knickpoint in the system is modeled as a perturbation to steady-state incision according to the stream power law, which is tested against the abandonment dates in seven caves. Model results for m/n = 0.68 are within previously published theoretical and empirical values of 0.5 to 1.0, but suggest that values for the drainage-area exponent m are several times higher
than previous studies. This may be caused by a stronger variance of discharge to drainage area in fluviokarst reaches compared with non-karst watersheds. Knickpoint migration rates in limestone bedrock channels of fluviokarst tributaries to the Cumberland River are calculated between 10-18 cm/year during the Plio-Pleistocene, with m = 1.91 and m/n = 0.79.

South China karst aquifer storm-scale hydrochemistry, 2004, Liu Z. H. , Groves C. , Yuan D. X. , Meiman J. ,
The peak cluster and peak forest karst regions of Southeast Asia form one of the earth's most extensive karst regions. Although there exists a rich, descriptive tradition of geomorphic work performed there, little quantitative study has been made of carbonate hydrochemistry and related aquifer/landscape behavior and evolution. In this paper, high-resolution measurements of ground water carbonate chemistry and flow were made and analyzed at two adjacent locations within the subtropical peak cluster karst of the Guilin Karst Experimental Site in Guangxi Province, China. While waters from a large, perennial spring represent the exit for the 2 km(2) catchment's conduit flow, a nearby well (within 5 m) measures water in the conduit-adjacent, fractured media. Results indicate that within peak cluster karst aquifer flow systems, spatially heterogeneous flow conditions can exist with respect to timing, magnitude, and, in some cases, direction of responses, as different controls can operate in the different flow system components. Stormscale chemical responses are controlled by dilution from rapid infiltration of rain water, CO2 gas sources and sinks, and water-carbonate rock interactions. At this particular location, there is also an influence from high pH recharge, apparently buffered by atmospheric limestone dust. An example of the varying controls on storm-scale responses within the flow system is that within the fractured medium, variations in the ground water calcite saturation index, a key parameter influencing rates of aquifer/landscape evolution, are small and controlled by CO 2 gas, while in the conduit they are more significant and dominated instead by dilution with rain water

An approach to the multi-element and multi-scale classification of the Limestone Pavement environment of Hutton Roof and Farleton Fell, Cumbria, UK, 2004, Huxter, Eric Andrew

 Limestone Pavements are highly significant components of the physiographic and ecological landscapes of the UK. As relict glacial features they are subject to destruction by natural processes but also by human intervention. This thesis identifies the most effective methods to monitor such change at a variety of temporal and spatial scales, based on the Morecambe Bay pavements at Hutton Roof and Farleton Fell. The starting point for such a study is a methodology to define the baseline on which to base change detection and the key to this is the development of a suitably detailed scene model. This must reflect the environment at the macro-, meso- and micro- scales and also incorporate considerations of the dynamics involved in the landscape evolution. The scene model (the Land Surface Classification Hierarchy (LSCH)) was developed by field measurement of the reflectance spectra of the main elements, biotic and abiotic, with measurements of the pavement surface in terms of the scale of karren development and the texture of the limestone itself. Study of the DEM allowed a fractal dimension to be established and also the nature of ice-flow and its contribution to pavement development, with extending flow, entraining fractured limestone blocks above a plastic, impermeable shale band, being the main mechanism. At the meso scale pavements were classified according to clint form derived from intra-pavement trends in grike direction calculated by Preferred Direction Analysis. Measurements of the key karren forms, runnels, solution pits and pipes and grikes allow assessment of their contribution to the variability of the pavement surface as an element of the scene model through the identification of solution domains. Identification of different lithologies allowed an investigation of spatial variation across the study area, although lithological control on karren form and magnitude is weaker than variability from age of exposure as shown by statistical analysis of karren morphometry using univariate comparative methods and Link diagrams, bivariate and multivariate regression, discriminant analysis, cluster analysis, multi-dimensional scaling and star diagrams with the derived Star Index. Pavements were classified according to karren morphometry. The traditional view of pedestals as an indicator of solution rates, and hence the concentration of solution at the surface, is challenged through the investigation of water flow over the pavement surface and the consideration of the role of lichen as a protective agent as well as the size of solution pits and grike width. It is suggested that only 10% of solution potential is achieved at the surface with 43% in the immediate epikarst. From this solution rate diagrams were developed, allowing the dating of exposure of pavements. These were shown to be within the period when human impact in the area was becoming significant and confirms an early anthropogenic impact on this element of the landscape. Further to this the development of grikes as emergent features was confirmed and this linked to the concept of breakthrough, allowing a model of grike development to be proposed, an important consideration in the dynamics of pavement change. At the micro scale texture analysis allowed the calculation of fractal measures which are related to variations in reflectance. The radiometric response of biotic and abiotic elements of the scene model was analysed confirming the facility of the baseline scene reflectance model of the pavement. Remotely sensed images from the Airborne Digital Camera were linked to ATM, CASI and TM images assessing the effect of scale on change detection and the evaluation of the pavement environment.

Rates of erosion and topographic evolution of the Sierra Nevada, California, inferred from cosmogenic Al-26 and Be-10 concentrations, 2005, Stock G. M. , Anderson R. S. , Finkel R. C. ,
Concentrations of cosmogenic Al-26 and Be-10 in cave sediments and bedrock surfaces, combined with studies of landscape morphology, elucidate the topographic history of the southern Sierra Nevada over the past 5 Ma. Caves dated by Al-26/Be-10 in buried sediments reveal that river incision rates were moderate to slow between c. 5 and 3 Ma (<= 0.07 mm a(-1)), accelerated between 3 and 1.5 Ma (c. 0.3 ram a(-1)), and then have subsequently become much slower (c. 0.02 mm a(-1)). Although the onset of accelerated incision coincides in time with both,postulated Pliocene tectonism and pronounced global climate change, we argue that it primarily represents the response to a discrete tectonic event between 3 and 5 Ma. Dated cave positions reveal that, prior to 3 Ma, river canyons displayed up to 1.6 km of local relief, suggesting that Pliocene rock uplift elevated pre-existing topography. Renewed incision beginning c. 3 Ma deepened canyons by up to 400 m, creating narrow inner gorges. Tributary streams exhibit strong convexities, indicating that the transient erosional response to Pliocene uplift has not yet propagated into upland surfaces. Concentrations of Al-26 and Be-10 in bare bedrock show that upland surfaces are eroding at slow rates of c. 0.01 mm a(-1). Over the past c. 3 Ma, upland surfaces eroded slowly while adjacent rivers incised rapidly, increasing local relief. Although relief production probably drove at least modest crestal uplift, considerable pre-Pliocene relief and low spatially averaged erosion rates suggest that climatically driven rock uplift is not sufficient to explain ail uplift implied by tilted markers at the western edge of the range. Despite the recent pulse of erosion, spatially averaged erosion rates are low, and have probably acted to preserve the broad topographic form of the Sierra Nevada throughout much of the late Cenozoic. Copyright (c) 2005 John Wiley & Sons, Ltd

Late Quaternary intensified monsoon phases control landscape evolution in the northwest Himalaya, 2005, Bookhagen B, Thiede Rc, Strecker Mr,
The intensity of the Asian summer-monsoon circulation varies over decadal to millennial time scales and is reflected in changes in surface processes, terrestrial environments, and marine sediment records. However, the mechanisms of long-lived (2-5 k.y.) intensified monsoon phases, the related changes in precipitation distribution, and their effect on landscape evolution and sedimentation rates are not yet well understood. The arid high-elevation sectors of the orogen correspond to a climatically sensitive zone that currently receives rain only during abnormal (i.e., strengthened) monsoon seasons. Analogous to present-day rainfall anomalies, enhanced precipitation during an intensified monsoon phase is expected to have penetrated far into these geomorphic threshold regions where hillslopes are close to the angle of failure. We associate landslide triggering during intensified monsoon phases with enhanced precipitation, discharge, and sediment flux leading to an increase in pore-water pressure, lateral scouring of rivers, and oversteepening of hillslopes, eventually resulting in failure of slopes and exceptionally large mass movements. Here we use lacustrine deposits related to spatially and temporally clustered large landslides (>0.5 km3) in the Sutlej Valley region of the northwest Himalaya to calculate sedimentation rates and to infer rainfall patterns during late Pleistocene (29-24 ka) and Holocene (10-4 ka) intensified monsoon phases. Compared to present-day sediment-flux measurements, a fivefold increase in sediment-transport rates recorded by sediments in landslide-dammed lakes characterized these episodes of high climatic variability. These changes thus emphasize the pronounced imprint of millennial-scale climate change on surface processes and landscape evolution

Weathering, geomorphic work, and karst landscape evolution in the Cave City groundwater basin. Mammoth Cave, Kentucky., 2005, Groves ? , Meiman J.

Weathering, geomorphic work, and karst landscape evolution in the Cave City groundwater basin, Mammoth Cave, Kentucky, 2005, Groves C. , Meiman J. ,
Following the pioneering work of Wolman and Miller [Wolman, M.G., Miller, J.P., 1960. Magnitude and frequency of forces in geomorphic processes. J. Geol., 68, 54-74.] in evaluation of geomorphic work and the frequencies and magnitudes of forces that drive it, a large number of quantitative studies have focused on the evolution of fluvial systems and transport of elastic sediment. Less attention has been given to understanding frequencies and magnitudes of processes in rock weathering, including investigation of rates at which solutes are removed from landscapes under various flow distributions as an analog to Wolman and Miller's [Wolman, M.G., Miller, J.P., 1960. Magnitude and frequency of forces in geomorphic processes. J. Geol., 68, 54-74.] concept of geomorphic work. In this work, we use I year of high-resolution flow and chemical data to examine the work done in landscape evolution within and at the outlet of Kentucky's Cave City Basin, a well-developed karst landscape/aquifer system that drains about 25 km(2). We consider both removal of solutes contributing to landscape denudation based on calcium mass flux as well as predicted dissolution rates of the conduit walls at the outlet of this basin based on limestone dissolution kinetics. Intense, short-duration events dominate. Storms that filled the Logsdon River conduit occurred < 5% of the year but were responsible for 38% of the dissolved load leaving the system and from 63% to 100% of conduit growth for various scenarios of sediment influence. Landscape denudation is a linear function of the amount of water moving through the system, but conduit growth rates, and thus rates of recharge area evolution from fluvial to karst surface landscapes, depend both on the amount of water available and the distribution of precipitation. © 2004 Published by Elsevier B.V

Cave inception and development in Caledonide metacarbonate rocks. PhD thesis, 2005, Faulkner, Trevor Laurence

This is the first comprehensive study of cave inception and development in metacarbonate rocks. The main study area is a 40000km2 region in central Scandinavia that contains over 1000 individual metacarbonate outcrops, and has nearly 1000 recorded karst caves (with passage lengths up to 5.6km). The area, which was repeatedly glaciated in the late Cenozoic, comprises a suite of nappes in the Cambro–Silurian Caledonides, a paleic range of mountains with terranes presently occurring on both sides of the northern Atlantic. Information about the stripe karst and non-stripe karst outcrops and their contained caves was assembled into computer-based databases, enabling relationships between the internal attributes of the caves and their external geological and geomorphological environments to be analysed. A rather consistent pattern emerged. For example, karst hydrological system distances are invariably shorter than 3.5km, and cave passages are positioned randomly in a vertical dimension, whilst commonly remaining within 50m of the overlying surface. This consistency is suggestive that the relevant cave inception, development and removal processes operated at a regional scale, and over long timescales. A consequence of the epigean association of caves with the landscape is that cave development can only be understood in the context of the geomorphological evolution of the host region. A review of the latest knowledge of the inception and development of caves in sedimentary limestones concluded that the speleogenesis of the central Scandinavian caves cannot be explained by these ideas. Five new inter-related conceptual models are constructed to explain cave development in metacarbonate rocks in the various Caledonide terranes. These are:
1. The tectonic inception model - this shows that it is only open fracture routes, primarily created by the seismic shocks that accompany deglaciation, which can provide the opportunity for dissolution of metalimestone rocks that have negligible primary porosity.
2. The external model of cave development - this black-box approach reveals how the formation, development and destruction of the karst caves are related to the evolution of their local landscape. During the Pleistocene, these processes were dominated by the cycle of glaciation, leading to cyclic speleogenesis, and the development of ever-longer and deeper systems, where the maximum distance to the surface commonly remains within one-eighth of the extent of change in local relief.
3. The hydrogeological model - this demonstrates that the caves developed to their mapped dimensions in timescales compatible with the first two models, within the constraints imposed by the physics and chemistry of calcite dissolution and erosion, primarily in almost pure water. Relict caves were predominantly formed in phreatic conditions beneath active deglacial ice-dammed lakes, with asymmetric distributions on east- and west-facing slopes. Mainly vadose caves developed during the present interglacial, primarily vadose, conditions, with maximum dimensions determined by catchment area. Combination caves developed during both deglacial and interglacial stages. The cross-sections of phreatic passages obey a non-fractal distribution, because they enlarged at maximum rates in similar timescales. Phreatic cave entrances could be enlarged at high altitudes by freeze / thaw processes at the surface of ice-dammed lakes, and at low altitudes by marine activity during isostatic uplift.
4. The internal static and dynamic model of cave development - this white-box approach demonstrates that many caves have ‘upside-down’ morphology, with relict phreatic passages overlying a single, primarily vadose, streamway. Both types of passage are guided along inception surfaces that follow the structural geology and fractures of the carbonate outcrops. Dynamically, the caves developed in a ‘Top-Down, Middle-Outwards’ (TDMO) sequence that may have extended over several glacial cycles, and passages in the older multi-cycle caves were removed downwards and inwards by glacial erosion.
5. The Caledonide model - this shows that the same processes (with some refinements) applied to cave development in most of the other (non-central Scandinavian) Caledonide areas. The prime influences on cave dimensions were the thicknesses of the successive northern Atlantic glacial icesheets and the positions of the caves relative to deglacial ice-dammed lakes and to local topography. Other influences included contact metamorphism, proximity to major thrusts, and marine incursions. With knowledge of these influences for each area, mean cave dimensions can be predicted.
The thesis provides the opportunity for the five models to be extended, so that cave development in other glaciated metamorphic and sedimentary limestones can be better understood, and to be inverted, so that landscape evolution can be derived from cave data.

Age constraints on cave development and landscape evolution in the Bighorn Basin of Wyoming, USA., 2006, Stock, G. M. , Riihimaki C. A. , Anderson R. S.
Cosmogenic 26Al/10Be burial dating and tephrochronology of cave deposits provide minimum estimates for the timing of cave development in the Bighorn Basin of Wyoming. Spence Cave is a linear phreatic passage formed along the fold axis of the Sheep Mountain anticline and subsequently truncated by 119 m of Bighorn River incision. A fine-grained eolian (windblown) sand deposit just inside the entrance yields a 26Al/10Be burial age of 0.31 0.19 million years (Ma). This represents a minimum age for the development of Spence Cave, and provides a maximum incision rate for the Bighorn River of 0.38 0.19 mm/yr. Horsethief Cave is a complex phreatic cave system located 43 km north of Spence Cave on a plateau surface ~340 m above the Bighorn River. Electron microprobe analyses of white, fine-grained sediment in the Powder Mountain section of Horsethief Cave confirm that this deposit is Lava Creek B fallout ash, erupted from the Yellowstone Plateau volcanic field ca. 0.64 Ma. Assuming this as a minimum age for the development of Horsethief Cave, extrapolation of the cave profile gradient westward to the Bighorn River gorge suggests a maximum incision rate of 0.35 0.19 mm/yr. Incision rates from both caves match well, and are broadly similar to other estimates of regional incision, suggesting that they record lowering of the Bighorn Basin during the late Pleistocene. However, we caution that deposition of both the Spence Cave sand and the Horsethief Cave volcanic ash may postdate the actual timing of cave development. Thus, these ages place upper limits on landscape evolution rates in the Bighorn Basin

Karst and landscape Evolution in parts of the Gamblier karst Province, Southeast South Australia and Western Victoria, Austalia [abstract], 2006, White Susan Q.

UPb geochronology of speleothems by MC-ICPMS, 2006, Woodheada Jon, Hellstroma John, Maasa Roland, Drysdaleb Russell, Zanchettac Giovanni, Devined Paul, Taylor Eve

Building upon the work of Richards et al. [1998. U–Pb dating of a speleothem of Quaternary age. Geochimica et Cosmochimica Acta 62, 3683–3688], we have developed a method for precise dating of speleothems beyond the range of the U–Th technique using the U–Pb decay scheme. By coupling low-blank sample preparation procedures and multi-collector inductively coupled plasma mass spectrometry (MC-ICPMS) analytical methodologies developed for low-level Pb-isotope analysis, we find that, under ideal circumstances (radiogenic speleothems with very low common Pb), U–Pb dating of speleothems is not only possible, but also produces excellent age resolution— often comparable to or better than U–Th studies. Corrections for initial isotopic disequilibrium are necessary and exert a strong control on the achievable age uncertainty. The technique will be of immediate benefit in extending speleothem-based climate proxy records beyond _500 ka and will also find other uses, such as the dating of associated sub-fossil remains, and providing constraints on rates of landscape evolution and neo-tectonic processes. Here we present initial results for speleothems from the Nullarbor Plain, Western Australia, and the Alpi Apuane, Italy. The Nullarbor samples provide important new constraints on the development of aridity in Australia during the late Tertiary/early Quaternary, while the Apuane samples offer insights into the landscape history and uplift of that region.

Formes et formations superficielles de la partie ouest du Causse de Sauveterre (Grands Causses, Aveyron et Lozre), 2007, Bruxelles Laurent , Simoncoinon Rgine, Guendon Jeanlouis, Ambert Paul
MORPHOLOGY AND SUPERFICIAL FORMATIONS OF THE WESTERN PART OF THE CAUSSE DE SAUVETERRE (GRANDS CAUSSES, AVEYRON AND LOZ?RE, FRANCE). In 2002, the Natural Regional Park of Grands Causses has coordinated a hydrogeological study of the western part of the Causse de Sauveterre, the northernmost of the Grands Causses. A multidisciplinary approach (geology, geomorphology, geochemistry and hydrology) was used to delineate the catchment area of the main springs and to estimate the vulnerability of karstic aquifers. The Grands Causses are situated in the southern part of the French Massif Central. The landscape is characterised by huge limestone plateaus cut by deep canyons. The morphologic study of the western part of the Causse de Sauveterre (Causse de Massegros and Causse de S?v?rac), combined with analysis of superficial formations, allows us to identify the main steps of landscape evolution. The discovery of bauxite and of many outcrops of Upper Cretaceous sandstone confirm that the Coniacian ingression invaded some paleo-landscapes developed within a long period of continental evolution which was initiated at the end of the Jurassic. During the Tertiary, many residual formations form covers of the limestone plateaus. We can distinguish alterites developed from different formations of the stratigraphic series (clay with cherts from Bajocian, dolomitic sand from Bathonian and Callovian, sandy clays from Cretaceous deposits) from some allochtonous deposits which can be found in some parts of the Causse de Massegros. These formations are found in association with morphological features (shelves, polj?s, fluvio-karstic valleys, sinkholes) and are more or less responsible of their development. Furthermore, some volcanic rocks cut through or even reused some of them. With the deepening of canyons and the base level drop, horizontal morphologies are preserved only where superficial formations are abundant and thick enough to maintain crypto-corrosion. Elsewhere, karst unplugging removes most of the superficial formations, and the karstic evolution tends to show a vertical development of morphologies and caves. Some springs, which benefit from a favourable lithologic, structural and hydrologic context, are more competitive and expand their catchment area at the expense of the other springs. Many superficial features express this dynamism on the plateau and allow us to determine the most sensible areas for water pollution and the most fragile ones for human activities.

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