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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 abime is (french.) 1. an abyss. 2. a wide, deep shaft, in limestone, the walls of which are vertical or overhanging [10].?

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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 gradient (Keyword) returned 230 results for the whole karstbase:
Showing 16 to 30 of 230
Humidity responses and the role of Hamann's organ of cavernicolous Bathysciinae (Coleoptera Catopidae)., 1978, Luccarelli Marco, Sbordoni Valerio
The humidity responses of Bathysciola derosasi and Leptodirus hohenwarti, two species of troglobitic Bathysciinae showing different degrees of adaptation to cave environment, have been studied. Intact and antennectomised subjects were tested using choice-chambers with various combinations of relative humidity alternatives (i.e. 20-100%, 50-100%, 90-100%, 50-90% and, as controls, 100-100%) to investigate the role played by the sense organs situated on the 7th, 9th and 10th antenna segments. The results show that intact-antenna subjects of both species are very sensitive to humidity gradients and that their intensity of reaction varies according to the intensity of stimulus, as previously reported by Argano, Sbordoni and Cobolli Sbordoni (1969). The antennectomy experiments show that receptors situated on the 7th, 9th and 10th antenna segments (Hamann's organ) are involved in hygroreception. In Leptodirus. insects antennectomised below the 9th segment show a reduced intensity of reaction, while those antennectomised below the 7th segment show no positive response at all. This seems to indicate that receptors in the 9th and 10th antennal segments have additive roles beyond that of the 7th. Further research is needed to ascertain whether the antennal organs of Bathysciinae may have yet further additional sensory roles (e.g. chemioreception) as their complex structure suggests.

Karst development in Ordovician carbonates: Western Platform of Newfoundland, Master of Science (MS) Thesis, 1978, Karolyi, Marika Sarolta

The Appalachian fold belt system in Newfoundland is divided into three tectonic divisions: Western Platform; Central Mobile Belt; Avalon Platform Rocks of the Western Platform range in age from Precambrian to Carboniferous. Major karst areas are found there is Ordovician and Carboniferous rocks. Karst features of the study area (Goose Arm to Bonne Bay Big Pond) are in the Ordovician carbonates of the undivided St. George and Table Head Formations, covering a few hundred square kilometers. Features include karren, sinkholes, sinking streams, and karst springs, caves and other solutional and collapse features.
In the study area multiple fold and faulting episodes complicate the geology. Extensive and probably repeated glaciations have produced rugged terrane with U-shaped valleys and as much as 300m relief on the carbonates. There is variable but thick till cover. A class or classes of ice-scoured closed depressions with internal drainage are recognized. Postglacial karst forms are limited to varieties of karren (mainly littoral), small sinkholes, and cave systems that are inaccessively small in most instances. Distribution of all karst features is highly irregular.
Hydrologic patterns follow fluvial, fluviokarstic and holokarstic drainage. Large number of sinking ponds have seasonal overflow channels. The ground water drainage routes are generally short and shallow, with varied hydraulic gradients. Few instances of ground water route integration to regional springs is found.
The water chemistry of the area displays a tight normal distribution of hardness. This is attributed to the ponding effect. Seasonal trends show an overall increase in total hardness and other parameters, with some ponds showing linear increases and others cyclic variations.
Karst type and distribution is complex and irregular, but both glaciokarstic and karstiglacial development is present. The majority of karst forms point to karstiglacial development where previous karst forms have been modified by ice. Karstification is controlled by geology, rock lithology, hydraulic gradients and glacial scour and infill. Karstic processes continue to operate today, modifying the scoured basins and creating new karst forms.

Hydrogeology of the Umm Er Radhuma aquifer, Saudi Arabia, with reference to fossil gradients, 1982, Bakiewicz W, Milne Dm, Noori M,
Much of North Africa and the Arabian peninsula, lying in the Saharan climate zone, are underlain by huge tabular sandstone and carbonate aquifers, ranging in age from Cambrian to Tertiary. These are often saturated with water of reasonable quality and form very valuable resources in an area often desperately short of water. The Palaeocene Umm Er Radhuma carbonate aquifer is one such formation which has been the subject of intensive recent investigation. The formation contains groundwater of a reasonable quality, has adequate transmission and storage characteristics and hence considerable potential for future development. The origin of the water in such aquifers is the subject of continuing controversy. It is not disputed that the water is moving under the influence of regional groundwater gradients but origins of these gradients are the subject of considerable argument. On the one hand, there are those who hold that the presently observed gradients are fossil remnants of conditions created by a much wetter climatic regime prevalent some thousands of years ago. Against this are those who maintain that the gradients, at least in part, reflect a present day system with groundwater discharge in approximate dynamic equilibrium with recharge. This paper examines the hydrogeology of a typical Middle Eastern formation of the disputed kind, the Umm Er Radhuma aquifer in Saudi Arabia, and, with the aid of analytical and numerical models, attempts to resolve the problem of the origin of the observed groundwater gradients and to discover the extent to which the past must influence present day plans for future development

Le rseau de la Diau, 1983, Lismonde, B.
The DIAU SYSTEM - Diau Cave is the resurgence of an important underground drainage system in the massif des Bornes in Haute-Savoie (France). The system's catchment is approximately 9km2, between an altitude of 1200m and 1800m. The average discharge is about 4001/s. Speleological explorations have discovered two sections of the master drainage cave (Diau and Pertuis caves). Two tributaries have also been explored. The total length of the Diau cave system is 14.9km with a height difference of 702m. The master cave occurs in the bottom of the Pertuis syncline at the boundary between the urgonian limestone and hauterivian marls. According to the gradient and the fractures, four types of gallery structure occur, of which two are vadose. The two known tributaries (inlet of the Grenoblois and Tanne des Mtores) follow a NW-SE anticlockwise shear fault, which exists in the Parmelan plateau fracture zone.

Shallow-marine carbonate facies and facies models, 1985, Tucker M. E. ,
Shallow-marine carbonate sediments occur in three settings: platforms, shelves and ramps. The facies patterns and sequences in these settings are distinctive. However, one type of setting can develop into another through sedimentational or tectonic processes and, in the geologic record, intermediate cases are common. Five major depositional mechanisms affect carbonate sediments, giving predictable facies sequences: (1) tidal flat progradation, (2) shelf-marginal reef progradation, (3) vertical accretion of subtidal carbonates, (4) migration of carbonate sand bodies and (5) resedimentation processes, especially shoreface sands to deeper subtidal environments by storms and off-shelf transport by slumps, debris flows and turbidity currents. Carbonate platforms are regionally extensive environments of shallow subtidal and intertidal sedimentation. Storms are the most important source of energy, moving sediment on to shoreline tidal flats, reworking shoreface sands and transporting them into areas of deeper water. Progradation of tidal flats, producing shallowing upward sequences is the dominant depositional process on platforms. Two basic types of tidal flat are distinguished: an active type, typical of shorelines of low sediment production rates and high meteorologic tidal range, characterized by tidal channels which rework the flats producing grainstone lenses and beds and shell lags, and prominent storm layers; and a passive type in areas of lower meteorologic tidal range and higher sediment production rates, characterized by an absence of channel deposits, much fenestral and cryptalgal peloidal micrite, few storm layers and possibly extensive mixing-zone dolomite. Fluctuations in sea-level strongly affect platform sedimentation. Shelves are relatively narrow depositional environments, characterized by a distinct break of slope at the shelf margin. Reefs and carbonate sand bodies typify the turbulent shelf margin and give way to a shelf lagoon, bordered by tidal flats and/or a beach-barrier system along the shoreline. Marginal reef complexes show a fore-reef--reef core--back reef facies arrangement, where there were organisms capable of producing a solid framework. There have been seven such phases through the Phanerozoic. Reef mounds, equivalent to modern patch reefs, are very variable in faunal composition, size and shape. They occur at shelf margins, but also within shelf lagoons and on platforms and ramps. Four stages of development can be distinguished, from little-solid reef with much skeletal debris through to an evolved reef-lagoon-debris halo system. Shelf-marginal carbonate sand bodies consist of skeletal and oolite grainstones. Windward, leeward and tide-dominated shelf margins have different types of carbonate sand body, giving distinctive facies models. Ramps slope gently from intertidal to basinal depths, with no major change in gradient. Nearshore, inner ramp carbonate sands of beach-barrier-tidal delta complexes and subtidal shoals give way to muddy sands and sandy muds of the outer ramp. The major depositional processes are seaward progradation of the inner sand belt and storm transport of shoreface sand out to the deep ramp. Most shallow-marine carbonate facies are represented throughout the geologic record. However, variations do occur and these are most clearly seen in shelf-margin facies, through the evolutionary pattern of frame-building organisms causing the erratic development of barrier reef complexes. There have been significant variations in the mineralogy of carbonate skeletons, ooids and syn-sedimentary cements through time, reflecting fluctuations in seawater chemistry, but the effect of these is largely in terms of diagenesis rather than facies

The speleogenetic role of air flow caused by convection. First contribution., 1986, Cigna Arrigo A. , Forti Paolo
In the past some authors described the speleogenetic role of convection in phreatic conditions. Similar effects exist also in the air-fiLled part of vadose passages of caves as a consequence of an air circulation due to a relevant temperature gradient; the effects can be enhanced by the presence of some acids as, e.g., H2S, H2SO4, etc. In this paper the conditions matching convection and condensation which produce typical forms, very similar to those found under phreatic conditions, are discussed both for limestone and gypsum caves.

The Geomorphology of the Jenolan Caves Area, 1988, Kiernan, Kevin

The Jenolan Caves occur in a small impounded fluviokarst developed in limestone of late Silurian age. This paper reviews present knowledge of the geomorphology of Jenolan. The surface and underground geomorphology has been strongly influenced by the lithology and structure of the limestone and the non-carbonate rocks that surround the karst. There is evidence in the present geomorphology of the inheritance of influences from palaeo landscapes. Abundant surficial and cave sediments reflect slope gradients and climatic conditions that have existed in the past. Despite the very limited size of the limestone outcrop there is a great variety in the karst, including many kilometres of underground passage and a range of cave morphologies and clastic and chemical sediments underground.

Modeling of regional groundwater flow in fractured rock aquifers, PhD Thesis, 1990, Kraemer, S. R.

The regional movement of shallow groundwater in the fractured rock aquifer is examined through a conceptual-deterministic modeling approach. The computer program FRACNET represents the fracture zones as straight laminar flow conductors in connection to regional constant head boundaries within an impermeable rock matrix. Regional scale fracture zones are projected onto the horizontal plane, invoking the Dupuit-Forchheimer assumption for flow. The steady state flow solution for the two dimensional case is achieved by requiring nodal flow balances using a Gauss-Seidel iteration. Computer experiments based on statistically generated fracture networks demonstrate the emergence of preferred flow paths due to connectivity of fractures to sources or sinks of water, even in networks of uniformly distributed fractures of constant length and aperture. The implication is that discrete flow, often associated with the local scale, may maintain itself even at a regional scale. The distribution of uniform areal recharge is computed using the Analytic Element Method, and then coupled to the network flow solver to complete the regional water balance. The areal recharge weakens the development of preferential flow pathways. The possible replacement of a discrete fracture network by an equivalent porous medium is also investigated. A Mohr's circle analysis is presented to characterize the tensor relationship between the discharge vector and the piezometric gradient vector, even at scales below the representative elementary volume (REV). A consistent permeability tensor is sought in order to establish the REV scale and justify replacement of the discrete fracture network by an equivalent porous medium. Finally, hydrological factors influencing the chemical dissolution and initiation of conduits in carbonate (karst) terrain are examined. Based on hydrological considerations, and given the appropriate geochemical and hydrogeological conditions, the preferred flow paths are expected to develop with time into caves.

Le karst de Vaucluse (Haute Provence), 1991, Mudry J. , Puig J. M.
The catchment area of the Fontaine de Vaucluse system is more than 1100km2 wide, with an average altitude of 870m. The thickness of the Lower Cretaceous limestone (1500m) gives the system a very thick (800m) unsaturated zone. Karstification is highly developed (four shafts are more than 500m deep) as well as on the valley (pit of 300m depth inside the spring). The bottom of the shafts of the Plateau does not reach the saturated zone of the karst, as their flows are the chemical content of the seepage water. The maximum hydraulic gradient from the Plateau to the spring is low, only 0.3%. Dye tracings permit the assignment of the Ventoux-Lure rang (including its calcareous northern slope with a southward dipping) and the Vaucluse Plateau in the catchment area. The water balance computed by altitude belts shows that the rainfall strongly increases with altitude: 120mm at 200m, 1380mm over 1800m. The dynamic of the system, studied by discharge and physical and chemical content, shows of a well karstified media, that reacts with slight inertia upon the rainy periods, and that is made up of important reserves, particularly within the unsaturated zone, that supply long decline and depletion episodes.

Quaternary calcrete, silcrete and gypcrete duricrusts in Karinga Creek drainage system, central Australia, contain abundant late-stage diagnetic features. These indicate repeated episodes of dissolution, precipitation and mobilization of duricrust components in the landscape, following the initial development of the duricrust mantle. 'Mature' duricrust profiles incorporate assemblages of diagnostic textural features and fabrics that clearly indicate the extent of karstification during the past 27 000 years. Diagenetic features in the duricrusts permit recognition of the stages involved in vadose modifications of compositional, textural and morphological features and, hence, assessment of the impact of karst dissolution, precipitation and mobilization of duricrust components under prevailing environmental conditions. At landscape level, the continued development of secondary porosity-permeability zones in topographically elevated areas, and maintenance of effective topographic gradients for soil creep are considered essential for redistribution of duricrust components and lateral and vertical extension of karst features within the Quaternary duricrust mantle. Although developing over a comparatively short span of time, late-stage modification of the Quaternary duricrusts has important implications for evolution of Quaternary landscapes and distribution of groundwater discharge-recharge patterns. Accordingly, differential dissolution and reprecipitation within the duricrust profiles have progressively given way to development of karst solution pipes and cavities, with the latter now acting as effective conduits for recharge of local aquifers in the region

Limestone caves form along ground-water paths of greatest discharge and solutional aggressiveness. Flow routes that acquire increasing discharge accelerate in growth, while others languish with negligible growth. As discharge increases, a maximum rate of wall retreat is approached, typically about 0.01-0.1 cm/yr, determined by chemical kinetics but nearly unaffected by further increase in discharge. The time required to reach the maximum rate is nearly independent of kinetics and varies directly with flow distance and temperature and inversely with initial fracture width, discharge, gradient, and P(CO2). Most caves require 10(4) - 10(5) yr to reach traversable size. Their patterns depend on the mode of ground-water recharge. Sinkhole recharge forms branching caves with tributaries that join downstream as higher-order passages. Maze caves form where (1) steep gradients and great undersaturation allow many alternate paths to enlarge at similar rates or (2) discharge or renewal of undersaturation is uniform along many alternate routes. Flood water can form angular networks in fractured rock, anastomotic mazes along low-angle partings, or spongework where intergranular pores are dominant. Diffuse recharge also forms networks and spongework, often aided by mixing of chemically different waters. Ramiform caves, with sequential outward branches, are formed mainly by rising thermal or H2S-rich water. Dissolution rates in cooling water increase with discharge, CO2 content, temperature, and thermal gradient, but only at thermal gradients of more than 0.01-degrees-C/m can normal ground-water CO2 form caves without the aid of hypogenic acids or mixing. Artesian flow has no inherent tendency to form maze caves. Geologic structure and stratigraphy influence cave orientation and extent, but alone they do not determine branch-work versus maze character

A ground water monitoring study was conducted for the triazine herbicide simazine at 11 sites in the United States. The study used carefully selected, small-scale sites (average size: about 33 acres) with documented product use and sensitive hydrogeological settings. The sites selected were Tulare County, California (two sites); Fresno County, California; Sussex County, Delaware; Hardee and Palm Beach counties, Florida; Winnebago County, Illinois; Jackson County, Indiana; Van Buren and Berrien counties, Michigan; and Jefferson County, West Virginia. These sites satisfied the following criteria: a history of simazine use, including the year prior to the start of the study; permeable soil and vadose zone; shallow depth to water; no restrictive soil layers above the water table; and gentle slopes not exceeding 2 percent. A variety of crop types, climates, and irrigation practices were included. Monitoring well clusters (shallow and deep) were installed at each site except in California and West Virginia, where only shallow wells were installed. Simazine was monitored at these sites at quarterly intervals for a two-year period during 1986-1988. The results of the study showed that out of 153 samples analyzed, 45 samples showed simazine detections. A substantial majority of the detections (32 out of 45) occurred in Tulare, Fresno, and Jefferson counties. The detections in these areas were attributed to mechanisms other than leaching, such as drainage wells, karst areas, surface water recharge, or point source problems. An additional 11 detections in Van Buren County were apparently due to an unknown upgradient source. Only one detection (in Palm Beach County, Florida) near the screening level of 0.1 ppb was attributed to possible leaching. The results of this investigation support the hypothesis that simazine does not leach significantly under field use conditions

Karst hydrogeology of the Canadian Rocky Mountains, PhD Thesis, 1991, Worthington, Stephen Richard Hurst

An analysis of the discharge and hydrochemical variations of contrasting springs at Crowsnest Pass showed they were part of a vertical hierarchy in the aquifer, in which underflow and overflow components play a dominant role. It was found that karst springs at Crowsnest Pass and elsewhere show a range between two end members. Thermal springs have long, deep flow paths, with high sulphate concentrations, low discharge variance and low flow velocities. Overflow springs have local shallow flow paths, low sulphate, high discharge variance, and high flow velocities. Intermediate between these end members are underflow springs; in the Rocky Mountains these are mostly aggraded, and give the sustained winter flow and high sulphate concentrations found in major rivers. It was found that underflow or overflow behaviour is able to explain most of the contrasts found between karst springs in discharge and sulphate concentrations. Conversely, differences in bicarbonate concentration are principally due to the ratio of allogenic to autogenic recharge to the aquifer. Hydraulic analysis showed that gradients decrease in the downstream direction, and are typically 0.0001-0.05 at maximum discharges, that friction factors vary by a factor of $>$1000, and that most active conduits have closed-channel flow and are in dynamic equilibrium with sediment supply. The analysis of the hydrological data from Crowsnest Pass and elsewhere has led to the development of a new conceptual model for groundwater flow in karst, in which the Hagen-Poiseuille flow net conditions the aquifer for conduit development, and determines where the conduits will be. The model explains why most conduits are in dynamic equilibrium with sediment supply, why temperate karst springs are mostly vauclusian, what the mean time for speleogenesis is, how $>$98% of the solution of limestone is in the surficial zone, and why there are karstic hot springs in the Rocky Mountains and elsewhere. The model enables predictions to be made of sink to resurgence flow velocities, of conduit depth below the water table, of the ratio of beds to joints used by conduits, of the spacing between cave tiers, and of the depth of vauclusian springs. This new understanding of how karstic aquifers develop and function gives a powerful predictive ability to karst hydrogeology.

The karst aquifer of the well-known Fontaine de Vaucluse has been recently studied, results have been got about delimitation of the system and its working. Geological data (lithology and structure) have allowed to delimit an 1115 Km2 intake area including Ventoux-Lure north facing range (1,909-1,826 m) and the Plateau which is prolonging it southwards (Fig. 1 and 2). The average altitude of the whole area, obtained by balancing elevation belt surfaces, is about 870 m. This elevation squares with results of tracing tests (Fig. 3), environmental physical, chemical and isotopic tracings, that allow to value a 850 m average altitude for the intake area (Fig. 4). The moisture balance has been computed from an altitude belts climatic model, using local rain an temperature gradients (Fig. 5 and Table II), because the weather network is not representative. So, rainfalls rise of about 55 mm per 100 m elevation and temperature decreases of about 0.5-degrees-C per 100 m. The consequence of these two antagonist phenomena is the quasi constant value of actual evapotranspiration on each altitude belt. With the Fig. 7 organigram, curves of effective rainfalls and infiltration coefficient versus elevation can be plotted (Fig. 6). This computation shows that 3/4 of the total and the whole of dry season effective rainfalls are provided by the part of the intake area situated above the average altitude: on the lowest belt, effective rainfalls are only 120 mm per year and increase to 1380 mm on the upper section (Fig. 8 and Table 1). The weighted effective rainfalls are about 570 mm per year for the whole intake area. Hydrodynamical and physico-chemical studies show, despite its large size, the weak inertia of the system, so proves its good karstification, that confirms for the whole system the pin-point speleological observations. The discharge of the spring, which average value is 21 m3.s-1 (only 18 for the last ten years), can exceed 100 m3.s-1 and the minimum has never been lower than 3.7 m3.s-1 (Fig. 9). When it rains on the intake area, the increase of the discharge is very sudden in a rainy period : one to four days. This short delay is due to seepage through epikarst and unsaturated zone. During dry periods, the spring reaction is deadened, due to storage in the unsaturated zone. The silica content distribution was plotted during several hydrokinematical phases (Fig. 10). It shows: an almost unimodal distribution for the 8 km2 fissured limestone aquifer of Groseau; a multimodal one for the 1115 km2 karst aquifer of Fontaine de Vaucluse. This proves that karstification is more important than size in the response of the system. Weak summer rainfalls do not influence the discharge, nevertheless they influence chemistry of the spring water, and so interrupts the water depletion phasis. Then, the decrease of discharge can continue after the end of the chemical depletion phasis, water which is overflowing after summer rainfalls (in a dry period) is influenced hy the chemistry of seepage water : on the graph of a principal components analysis, done on chemical variables. an hysteresis phenomenon can be seen (Fig. 11). A discriminant analysis (Fig. 12) confirms that these autumn waters, with high ratio seepage tracers, are not reserve waters from the saturated zone. The ratio of reserve water in the total discharge, is preponderant: 3/4 and 2/3 respectively of the yearly runoff volumes for 1981 and 1982 (Fig. 13), but an important part of these reserves can be stored in the unsaturated zone. This storage capacity can be valued by different means: transposing to Vaucluse (1115 km2) the volume measured on another karst system in the Pyrenees (13 km2); it gives about 100 million m2; using setting parameters of Bezes model (1976) on the same aquifer: it gives 113 million m3; using depletion curves, that show, for instance during the 1989 summer and autumn dry period, a 80 million m3 volume. In all cases, we get a value of about one hundred million m3 for the storage capacity of the unsaturated zone. With a 20 m range of fluctuation for the water table and with a 10(-2) specific yield, on a 500 to 1,000 km2 saturated zone, the zone of fluctuation can release about 10 to 20 million m3. Then, the volume of water stored in the whole saturated zone, with a 300 m minimum thickness (depth of the waterlogged pit of the Fontaine), a 500 km2 minimum surface and a 10(-3) specific yield, is about 150 million m3, including 27 million m3 stored in the channels. So, the unsaturated zone represents a significant part of the whole storage capacity and most of the yearly renewable reserves. Paradoxically, the biggest french spring is not tapped at all; as its intake area is neither a regional nor a national park, no general protection covers it : because of its good karstification, the vulnerability of the system is important. Good quality of water is attributable to the low population and human activities density on the intake area (4 A great part of the intake area is uncultivated (large forest and ''garrigues'' areas). Due to the lack of surface water and scantness of soils, agriculture is not intensive (lavender, thyme, sage and bulk wheat fields. meadowlands). On the mountainous zone, roads are salted in winter and snowmelt water can reach a significantly high chloride ratio than in a natural climatic functioning (for instance 25 mg.l-1 in Font d'Angiou where the ratio would have been 3 mg.l-1). As tourism is developing both on the mountain and on the plateau, the management of the highest intake area must be carefully held: its part is preponderant in the feeding of the system

Le gouffre Jean-Bernard (1602 m, Haute-Savoie), coulements souterrains et formation du rseau, 1993, Lips B. , Gresse A. , Delamette M. , Maire R.
With its depth of 1602m and development of more than 20 km, the Jean-Bernard system provides a clear view of an alpine karst system with a steep gradient and reduced watershed (4 km2). Over the last 30 years, hundreds of explorations led by the caving club Vulcain (Lyon) have resulted in a thorough knowledge of the cave. The system develops in a syncline formed from urgonian limestone (Lower Cretaceous). Two parts may be distinguished: a complex upper part with numerous dry phreatic tubes, and a lower part, which is restricted to a high meander. A tracing carried out in 1992 has allowed us to locate the outlet in the riverbed of the Clvieux creek (alt. 780m). The former spring of the upper part must have been situated on the level of the lower entrance (about 1800m) and could date back to the end of the Tertiary when the valley was less deep. The quaternary period is responsible of the entrenching of the old galleries, for the destruction of speleothems and the genesis of the lower underground delta, between -1400m and -1600m.

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