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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. ...

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. ...

Speleology in Kazakhstan

Shakalov on 11 Jul, 2012
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 surface mine is strip mine [16].?

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Chemistry and Karst, White, William B.
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Geochemical and mineralogical fingerprints to distinguish the exploited ferruginous mineralisations of Grotta della Monaca (Calabria, Italy), Dimuccio, L.A.; Rodrigues, N.; Larocca, F.; Pratas, J.; Amado, A.M.; Batista de Carvalho, L.A.
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
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Your search for runoff (Keyword) returned 113 results for the whole karstbase:
Showing 1 to 15 of 113
On subterranean confluences., 1965, Bleahu Marcian
The development of a subterranean drainage system depends on the way in which subterranean confluences between different rivers can be formed. Different from surface, in which confluences are determined by processes related to the surface runoff of water, in subterranean karst confluences have a random pattern and are related to certain circumstances independent of the underground flow. These conditions are: pre-existence of circulation ways and the way they are distributed in space. At these the peculiar processes of subterranean karst flow determined by the flow under pressure, the only one that can explain the systematic appearance of confluences, have to be added. In function of these parameters a morphogenetic classification of subterranean confluences is given.

Underground solution canyons in the Central Kentucky karst, U.S.A., 1967, Watson Richard A.
Solution canyons are underground voids 1 to 15 + meters wide, 3 to 45 + meters high, and 30 to 300 + meters long. Floors are stepped, ceilings level. Size increases downstream. Their course is sinuous, with some angularity. They occur parallel to and directly under or slightly offset from the thalwegs of re-entrant valleys tributary to major karst valleys. A section across a re-entrant and underlying solution canyon shows a rough hour-glass shape. Solution canyons are related genetically to solutional vertical shafts, forming where removal of the impermeable sandstone caprock permits the vertical descent of water through jointed limestone. Surface runoff concentrates along re-entrant thalwegs where a largo quantity of water goes underground. This water, plus subsurface water flowing over the caprock breached by the valleys, follows the easiest route to baselevel down major vertical joints oriented parallel to the thalwegs. Solution by water seeping down these joint planes forms solution canyons.

Seminar on Karst Denudation - Effect of Runoff on Corrosion Intensity in the North-west Dinaric Karst, 1972, Gams Ivan

Karst processes of the eastern upper Galilee, Northern Israel, 1974, Gerson R,
Karst processes dominate most of the geomorphic activity in the Upper Galilee, consisting mainly of dolomites and limestones. Study of the chemical evolution of water passing through the karst hydrologic cycle clearly shows that the major portion of its carbonate solute is gained subaerially and in the upper part of the vadose zone. Most cave and spring water is already saturated with respect to aragonite and calcite.The karst depressions typical to surface morphology are mostly associated with fault-line traces. Their evolution is possible mainly in areas sloping initially less that 5[deg].The absence of evolved caves, representing well-developed karst of an earlier period, is attributed mainly to the marginal climate throughout the past combined with tectonic, and hence hydrologic, instability of the region.The discharge of the karst prings shows clearly dependence on annual precipitation, with a lag of about 2 years of the response to drought or more humid periods. Long-term fluctuations are larger in the smaller T'eo Spring than in the affluent 'Enan Springs.Most of the denuded material is extracted from the region as dissolved load via underground conduits and only small amounts as clastics. Mean long-term denudation is approximately 20 mm/1000 years, averaged for the surface area contributing to the springs.In spite of the above, most topographic forms are shaped by runoff erosion, active during medium to high intensity rainstorms. Solution processes prevail during low to medium rainfall intensities, while different parts of the region are denuded at similar rates. Even in karst depressions, erosion becomes dominant after their bottoms are covered by almost impervious terra-rossa mantle

New data on the Foraminifera of the groundwaters of Middle Asia., 1976, Mikhalevich Valeria I.
New data obtained during the expedition to Middle Asia (1973) essentially enlarge our knowledge of foraminifera living in underground waters. Seven new species were discovered in the wells of the Kara-Kum and Ust-Urt deserts. All of them contain cytoplasma. The wells are situated in the region of bedding of underground waters of the heightened salinity in the zone of balance of runoff and evaporation. The majority of the species described in our work like many of the species recorded from the underground waters earlier (Brodsky, 1928; Nikoljuk, 1968; Jankovskaja and Mikhalevich, 1972) belong to the genera living in coastal brackish parts of tropical seas. This fact confirms the supposition of Brodsky about the transition of the marine coastal foraminiferal fauna to underground habitats after the regression of the sea. This fauna is a part of the underground fauna called by Nalivkin (1965) "the planetar fauna of the new type".

Karst Geomorphology of the Bruce Peninsula, Ontario, PhD Thesis, 1976, Cowell, Daryl William

This is the first detailed examination of the karst geomorphology of the Bruce Peninsula. It attempts to review all aspects including pavement phenomena and formation (microkarst features), surface and subsurface karst hydrology (meso to macro scale) and water chemistry. The latter is based on over 250 samples collected in 1973 and 1974.
The dolomite pavement is the best example of its kind that has been described in the literature. It covers much of the northern and eastern parts of the peninsula and can be differentiated into three types based on karren assemblages. Two of these are a product of lithology and the third reflects local environmental controls. The Amabel Formation produces characteristic karren such as rundkarren, hohlkarren, meanderkarren, clint and grike, kamentizas and rillenkarren on glacially abraded biohermal structures. The Guelph Formation develops into a very irregular, often cavernous surface with clint and grike and pitkarren as the only common recognizable karren. The third assemblage is characterized by pitkarren and is found only in the Lake Huron littoral zone. Biological factors are believed to have played a major role in the formation of the pavement. Vegetation supplies humic acids which help boost the solution process and helps to maintain a wet surface. This tends to prolong solution and permit the development of karren with rounded lips and bottoms.
Three types of drainage other than normal surface runoff are found on the Bruce. These are partial underground capture of surface streams, complete underground capture (fluvio-karst), and wholly vertical drainage without stream action (holokarst). Holokarst covers most of the northern and eastern edge of the peninsula along the top of the escarpment. Inland it is replaced by fluvial drainage, some of which has been, or is in the process of being captured. Four perennial streams and one lake disappear into sinkholes. These range from very simple channel capture and resurgence, as shown by a creek east of Wiarton, to more mature and complex cave development of the St. Edmunds cave near Tobermory. Partial underground capture represents the first stage of karst drainage. This was found to occur in one major river well inland of the fluvio-karst and probably occurs in other streams as well. This chapter also examines the possible future karst development of the Bruce and other karst feature such as isolated sinks and sea caves.
The water chemistry presented in Chapter 5 represents the most complete data set from southern Ontario. It is examined on a seasonal basis as well as grouped into classes representing water types (streams, Lake Huron and Georgian Bay, inland lakes, swamps, diffuse springs and conduit springs). The spring analyses are also fitted into climatic models of limestone solution based on data from other regions of North America. It was found that solution rates in southern Ontario are very substantial. Total hardness ranges from 150 to 250 ppm (expressed as CaCO3) in most lakes and streams and up to 326 ppm in springs. These rates compare with more southerly latitudes. The theoretical equilibrium partial pressure of CO2 was found to be the most significant chemical variable for comparing solution on different kinds of carbonates and between glaciated and non-glaciated regions. Expect for diffuse flow springs and Lake Huron, the Bruce data do not separate easily into water types using either graphical or statistical (i.e. Linear Discriminant Analysis) analyses. This is partly because of the seasonality of the data and because of the intimate contact all waters have with bedrock.


A Triple Dye Tracing Experiment At Yarrangobilly, 1976, Spate A. P. , Jennings J. N. , Ingle Smith D. , James Julia M.

Rhodamine WT, leucophor HBS and fluorescein were inserted into Deep, Eagles Nest and Traverse Creeks respectively, all sinking wholly or partly into the limestone at Yarrangobilly, as part of a program to determine the catchment area of Hollin Cave. Hollin Cave and three other major springs, together with the Yarrangobilly River above, between and below these springs, were sampled for various periods manually or by machine. Heavy rains began a day after dye insertion. Various lines of evidence and analysis, including the plotting of regression residuals between different wavebands as time series, showed that the relevant fluorescent wavebands were affected by rises in natural fluorescence in the runoff, probably of organic origin. Green was affected most, then blue, and orange only slightly. It was possible to identify a dye pulse of rhodamine at Hollin Cave, most probably representing all the dye put in. A leucophor dye pulse was also identifiable here but a load curve could not be constructed because of probable interference by changing natural fluorescence. Tracing by fluorescein became impossible. Interference between the three dyes was demonstrated. The implications for future quantitative tracing here are discussed.


Karst Hydrogeology and Geomorphology of the Sierra de El Abra and the Valles-San Luis Potosí Region, México, PhD Thesis, 1977, Fish, Johnnie Edward

The general objective of this work was to develop a basic understanding of the karst hydrology, the nature and origin of the caves, the water chemistry, the surface geomorphology, and relationships among these aspects for a high relief tropical karst region having a thick section of limestone. The Valles-San Luis Potosí region of northeastern México, and in particular, the Sierra de El Abra, was selected for the study. A Cretaceous Platform approximately 200 km wide and 300 km long (N-S) delimits the region of interest. A thick Lower Cretaceous deposit of gypsum and anydrite, and probably surrounded by Lower Cretaceous limestone facies, is overlain by more than 1000 m of the thick-bedded middle Cretaceous El Abra limestone, which has a thick platform-margin reef. The Sierra de El Abra is a greatly elongated range along the eastern margin of the Platform. During the late Cretaceous, the region was covered by thick deposits of impermeable rocks. During the early Tertiary, the area was folded, uplifted, and subjected to erosion. A high relief karst having a wide variety of geomorphic forms controlled by climate and structure has developed. Rainfall in the region varies from 250-2500 mm and is strongly concentrated in the months June-October, when very large rainfalls often occur.
A number of specific investigations were made to meet the general objective given above, with special emphasis on those that provide information concerning the nature of ground-water flow systems in the region. Most of the runoff from the region passes through the karstic subsurface. Large portions of the region have no surface runoff whatsoever. The El Abra Formation is continuous over nearly the whole Platform, and it defines a region of very active ground-water circulation. Discharge from the aquifer occurs at a number of large and many small springs. Two of them, the Coy and the Frío springs group, are among the largest springs in the world with average discharges of approximately 24 m³/sec and 28 m³/sec respectively. Most of the dry season regional discharge is from a few large springs at low elevations along the eastern margin of the Platform. The flow systems give extremely dynamic responses to large precipitation events; floods at springs usually crest roughly one day after the causal rainfall and most springs have discharge variations (0max/0min) of 25-100 times. These facts indicate well-developed conduit flow systems.
The hydrochemical and hydrologic evidence in combination with the hydrogeologic setting demonstrate the existence of regional ground-water flow to several of the large eastern springs. Hydrochemical mixing-model calculations show that the amount of regional flow is at least 12 m³/sec, that it has an approximately constant flux, and that the local flow systems provide the extremely variable component of spring discharge. The chemical and physical properties of the springs are explained in terms of local and regional flow systems.
Local studies carried out in the Sierra de El Abra show that large conduits have developed, and that large fluctuations of the water table occur. The large fossil caves in the range were part of great deep phreatic flow systems which circulated at least 300 m below ancient water tables and which discharged onto ancient coastal plains much higher than the present one. The western margin swallet caves are of the floodwater type. The cave are structurally controlled.
Knowledge gained in this study should provide a basis for planning future research, and in particular for water resource development. The aquifer has great potential for water supply, but little of that potential is presently used.


Mean Annual Runoff and the Scallop Flow Regime in a Subarctic Environment: Preliminary Results from Svartisen, Norway, 1983, Lauritzen Se. , Ive A. , Wilkinson B.

Further Studies at the Blue Waterholes, Cooleman Plain, N.S.W., 1969-77, Part I, Climate and Hydrology, 1983, Jennings, J. N.

Previous study of the temporal and spatial distribution of limestone solution at Cooleman Plain rested on monthly discharges and water analyses of the Blue Waterholes over 4 years. For this study automatic recording of discharge (8 years), rainfall (8 years), evaporation (7 years) and temperature (4 years) was attended by variable success in the face of interference, rigorous climate and inaccessibility. The most important aspect of the climatic data was the support obtained for the earlier assumption of similar water balances in the forested igneous frame and the grassland limestone plain. Runoff was again shown to be highly variable from year to year and to have an oceanic pluvial regime, with a summer-autumn minimum owing much to evapo-transpiration. The flow duration curve from daily discharges puts this karst amongst those where neither extremely high nor low flows are important. The stream routing pattern offsets the effect of 71% of the catchment being on non-karst rocks, damping flood events. An inflection of 700 l/s in a flow duration plot based on discharge class means is interpreted as the threshold at which surface flow down North Branch reaches the Blue Waterholes. Storages calculated from a generalised recession hydrograph parallel Mendip data where baseflow (fissure) storage provides most of the storage and quickflow (vadose) storage only a secondary part. Water-filled conduit storage (the phreas) could not be determined but is considered small. The baseflow storage seems large, suggesting that it can develop independently of caves in some measure. A quickflow ratio for floods derived by Gunn's modification of the Hewlett and Hibbert separation line method appears relatively low for a mainly non-karst catchment and is again attributed to the routing pattern. For analysis of variation of the solute load over time, estimates of daily discharge during gaps in the record where made for the author by Dr. A.J. Jakeman and Mr. M.A. Greenaway (see Appendix). A small number of discharge measures of two contrasted allogenic catchments of the igneous frame shows a unit area yield close to that for the whole catchment. Together with the guaging of most of the allogenic inputs, this supports the idea that the water yield is much the same from the forested ranges and the grassland plain. This is important for the estimation of limestone removal rates.


Further Studies At The Blue Waterholes, Cooleman Plain, N.S.W., 1969-77, Part II, Water Chemistry And Discussion, 1983, Jennings, J. N.

The 1969-77 data confirm that groundwater temperature is significantly higher than air temperature at mean catchment altitude but provide only partial support for an explanation in terms of soil temperature and insulation of drainage from cold air ponding over the Plain. Higher pH of output than input streams is attributed mainly to percolation water chemistry. Water chemistry of two contrasted input streams suggests non-karst rock weathering has an important effect on allogenic input streams. An inverse relationship between carbonate hardness and output discharge is found again and attributed mainly to faster transit through the limestone at high flows. Summer has a steeper regression than winter due to precipitation and high flows depressing carbon dioxide and carbonate concentrations more in that season than in winter. Picknett graphs show how solutional capacity varies through the hydrologic system, with aggressive input streams, mainly saturated percolation water, and rarely saturated output springs because of the allogenic component in the last. The total carbonate load of Cave Creek is directly related to discharge, with little seasonal difference so the annual regression is chosen for later calculation. When the carbonate load duration curve and frequency classes for Cave Creek are compared with those for other karsts, it falls into an intermediate class in which neither very high nor low flows dominate the pattern. This is attributed to a combination of a large allogenic input with a complex routing pattern. Consideration of most input stream solute concentration on one occasion indicates such close dependence on catchment geology that doubt is cast on the smallness of the 1965-9 allocation of carbonate contribution from non-karst rock weathering to the allogenic input. This is explained by new CSIRO rainfall chemistry figures from the Yass R. catchment which are smaller than those used before and by elimination of a previous error in calculation. This time subtraction of atmospheric salts is done on a daily basis with a decaying hyperbolic function. Correction of Cave Creek output for allogenic stream input follows the method adopted in 1965-9 but on a firmer basis, with the assumption of approximately equal water yeild per unit area from the non-karst and karst parts of the catchment being more factually supported than before. It remains a substantial correction. The correction for subjacent karst input to Cave Creek is also improved by putting the calculation in part on a seasonal basis; it remains small. The exposed solute load output shows the same seasonal pattern as was determined earlier, with a winter/spring maximum, and it again evinced much variation from year to year. So did annual rates. The mean annual loss of 29 B was slightly greater than for 1965-9. If this difference is real and not an experimental error, the reduced allowance for atmospheric salts and greater annual rainfall in the second period could explain the increase. This erosion rate of 29 B from an annual runoff of about 400mm places this karst where it would be expected in the world pattern of similar determinations in terms of both runoff and its proximity to the soil covered/bare karst dichotomy of Atkinson and Smith (1976). Combined with the other work at Cooleman Plain on erosion at specific kinds of site, an estimate of the spatial distribution of the limestone solution is presented. It agrees well with the similar attempt for Mendip by Atkinson and Smith (1976), when allowance is made for certain differences in method and context. The main conclusions are the great role of solution in the superficial zone and the unimportance of the contribution from caves. Conflict between this process study and the geomorphic history of Cooleman Plain remains and once again an explanation is sought in long persistence of a Tertiary ironstone cover inhibiting surface solution.


Les massifs karstiques des Alpes occidentales, trame structurale et bioclimatique, 1984, Nicod, J.
THE KARSTIC MASSIFS OF WESTERN ALPS: structural and bioclimatic framework - The structural conditions determine several types of karst units: the northern Prealps (thrusts), the southern Jura (folded or tabular), the southern Prealps (faulted and folded plateaus), the complex land of Low Provence, and the high karsts of Inner Alps. The bioclimatic framework explains the altitudinal sequence of current processes. The value of the runoff, the part of the snow, and the biochemical parameters (vegetation, CO2), have particularly holded the attention. The specific dissolution reaches its maximum in the wooded mountain karsts. Heritages also determine the landforms (glacial, periglacial, terra-rossa).

Hydrogologie karstique du polj d'lrmene, Bodrum (Turquie), 1985, Canik, B.
KARSTIC HYDROGEOLOGY OF THE IRMENE POLJE - BODRUM (TURKEY) - The Irmene polje (25 km2) is located in the Bodrum peninsula, Turkey. The formation exposed, are coloured argilaceous schists, blackish shales and sandstones of a paleozoic age. They are overlapped by unconformable carbonate formations of Early Triassic to Late Jurassic. The karstification is mostly developed on the non-dolomitic parts of the fissured limestones. The groundwater flow is generally northwards, towards coastal or submarine springs. Thus, it is calculated that a discharge of about 40 l/s can be obtained from possible wells to supply water for the Irmene village. We propose to increase the infiltration rate within the karstic aquifer by building barriers, which would favour runoff towards natural wells or sinks not active for the moment.

Groundwater chemistry and cation budgets of tropical karst outcrops, Peninsular Malaysia, I. Calcium and magnesium, 1989, Crowther J,
The discharge and chemical properties of 217 autogenic groundwaters were monitored over a 1-yr period in the tower karsts of central Selangor and the Kinta Valley, and in the Setul Boundary Range. Because of differences in soil PCO2, calcium concentrations are significantly higher in the Boundary Range (mean, 82.5 mg l-1) than in the tower karst terrain (44.6 mg l-1). Local differences in both source area PCO2 and amounts of secondary deposition underground cause marked intersite variability, particularly in the tower karst. Dilution occurs during flood peaks in certain conduit and cave stream waters. Generally, however, calcium correlates positively with discharge, since the amount of secondary deposition per unit volume of water decreases at higher flows. Magnesium concentrations and Mg:Ca Mg ratios of groundwaters are strongly influenced by bedrock composition, though bedrock heterogeneity and the kinetics and equilibria of carbonate dissolution reactions preclude extremely low or high Mg:Ca Mg values. Net chemical denudation rates range from 56.6 to 70.9 m3km2yr-1.The results are considered in relation to cation fluxes in surface runoff, soil throughflow and nutrient cycling. Preliminary calcium and magnesium budgets show that (1) dissolutional activity is largely confined to the near-surface zone; and (2) the annual uptake of calcium and magnesium by tropical limestone forests is similar in magnitude to the net solute output in groundwaters

WATER-BUDGET, FUNCTIONING AND PROTECTION OF THE FONTAINE-DE-VAUCLUSE KARST SYSTEM (SOUTHEASTERN FRANCE), 1992, Blavoux B, Mudry J, Puig Jm,
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 inh.km-2). 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

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