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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 buildup is the vertical distance the water table or potentiometric surface is raised, or the increase of the pressure head due to the addition of water [22].?

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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 rainfall (Keyword) returned 243 results for the whole karstbase:
Showing 16 to 30 of 243
Carbonate surface solution in the classical karst, 1987, Cucchi Franco, Finocchiaro Furio, Forti Fabio
The current research on the dissolution of carbonate rocks in the Karst of Trieste indicates that the average degradation of surfaces exposed to atmospheric agents is 0.028 mm/year with an average rainfall of 1350 mm. The maximum levels (0.031 mm/year) correspond to micro-crystalline limestones, the minimum values (0.014 mm/year) to dolomites.

Observations on the Buchan Karst During High Flow Conditions, 1987, Finlayson Brian, Ellaway Mark

In late July 1984 heavy rain at Buchan in East Gippsland produced widespread flooding and activated the dry valley network and vadose cave system on the Buchan limestones. The heavy rainfall was caused by the movement southwards along the New South Wales coast of a low pressure centre which originated in southeast Queensland. Intensity - frequency - duration analysis of the rainfall event indicates that while the 24 hour fall on the day the flooding occurred had a recurrence interval of only 1.75 years, the 96 hour and the 120 hour duration had recurrence intervals of 3.8 and 8.0 years respectively. The flood peak in the Buchan River had a recurrence interval of 4.3 years. These analyses indicate that the dry valleys and vadose cave systems are hydrologically active quite frequently under present climatic conditions. Water quality observations were made on surface streams and springs in the Buchan area during the flood and the results are compared with similar data collected under low flow conditions.

The Cleanup of Weebubbie Cave, 1987, Poulter, Norman

For many years Weebubbie Cave had been used as a water resource. This utilisation ceased somewhere around 1984. Although the active pump and piping were removed, the debris of previous exploiters remained. The description is given of the methods employed to remove the debris based on experience gained from an earlier cleanup in the Yallingup tourist cave. Weebubbie Cave 6N-2 is a large collapse doline located on the Hampton Tableland of the vast Nullabor Plain some 14km north of Eucla near the Western Australian border. The region is arid with an average rainfall of 125mm per year, although it has been known to fall (all) in one day. With summer temperatures sometimes reaching to 50 degree C, water is essential for survival. The predominating vegetation of saltbush and bluebush is well suited as stock feed.

Le karst du massif Moucherotte / Pic Saint-Michel (Isre, Vercors), 1991, Audra, Ph.
The karst of Moucherotte/Pic Saint-Michel (Vercors, Isre, France) - The massif of Moucherotte-Pic Saint Michel is located in the northeastern corner of the Vercors, in the area of Lans-en-Vercors and Saint-Nizier-du-Moucherotte. As anywhere in Vercors, this area is strongly marked by a dense karst relief. It harbours underground systems. Recent dye tracings (respectively from Sierre shaft, Choucas shaft, and Ira's Hole) allowed to determinate precisely the boundary of the catchment of the source called Bruyant. This basin spreads out from the Moucherotte to the Pic Saint-Michel, thus including a surface of 12km2. This is confirmed through the water balance. Of the 1600mm of yearly rainfall, 70% is infiltrated toward the source of the Bruyant. The water is conveyed through a main drain, probably mostly vadose, at the base of the recumbent fold. The landscape is due to the Quaternary processes. The two great landslides of "col de l'Arc" and of "Peuil" date back to this time. The glaciers have sculptured huge "combes" where many caves open, ancient places where sub-glacial waters were swallowing. These sub-vertical caves (which can measure up to 300m deep) with shafts and meanders, flow through large horizontal galleries older than the Quaternary (Combe Oursire shaft, Vallier cave). These galleries, hidden away in this huge limestone mass, are the witnesses of an earlier and very elaborate subterranean drainage. This system is entirely different from our present drainage system.

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.

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

Rillenkarren are defined as densely packed, rainfall generated, bedrock channels, forming on slopes. They are usually no more than a few centimetres in width. Their lengths are dependant on the downslope extent of exposed bedrock, Rillenkarren exist in many karst terraines on many types of rock. Rillenkarren on gypsum were measured at four differing sites in Nova Scotia. The results are compared with previous data for naturel rillenkarren on limestones. It was found that gypsum rillenkarren tend to exhibit a smaller mean width that those on limestone. Mean lengths could not be established because rillenkarren elongation on the gypsum was limited by the length of the exposed surface. These conclusions result from the first systematic study of naturally occurring rillenkarren on gypsum and are contrary to the previously speculated dimensions reported by various authors

This paper deals with various methods of solving the complex problems of the hydrological transformation of rainfall into runoff in karst terrains. As an example of a typical karst catchment, the Crnojevica spring, located in deep Dinaric karst, is used to illustrate, explain and solve several hydrological problems in karst. The introduction deals with the geographical, geological and meteorological factors which conditioned a specific system of surface and underground flows, typical for karst terrains. The paper also explains some basic activities related to the identification of such a system. Special attention has been paid to the karst terrain of the Cetinje polje and its flooding, which occurred in February 1986. This flood initiated numerous intensive investigations which made it possible to define the catchment area of Crnojevica spring and the volume of the underground karst reservoir

The Vrana Lake on the island of Cres in the Adriatic Sea represents a specific phenomenon of karst hydrology. The island of Cres covers an area of 404.3 km2 with an average volume, of 220 x 10(6) m3 of fresh water in the lake. The island has an average rainfall of 1,063 mm, with a Mediterranean climate. The lake has a bottom reaching a depth of 62 m below mean sea level. The average water level is 14 m above mean sea level. The most probable theories on the origin of the lake and its hydrologic-hydrogeologic functioning state that it is a flooded polje in karst. The water budget method was used to define the lake catchment area at approximately 25 km2. During the last six years, there has been drastic decrease of about 3 m in the lake's water level. This phenomenon was analyzed and it was calculated that 53 percent of the water-level decline was caused by water discharges from the lake to satisfy water supply demands, and 47 percent was due to a period of low precipitation during the analyzed period

Approche thorique _simplifie de la dissolution karstique, 1994, Gombert, P.
The specific behaviour of karsts makes the estimation of karstic denudation very difficult: discharge and water chemical variabili-ties are in fact major characteristics of aquifer karstic systems and cannot be properly estimated by the way of random sampling. The classical empirical methods provide generally high relative errors due to the bad knowledge of the hydrogeological catchment basin and even of the total number of springs. In the case of CORBEL's or WILLIAM's empirical formulas, average relative error can be estimated to about 100 % for a normally known aquifer karstic system : therefore it is impossible to compare different karsts that have not been studied with the same accuracy. The theoretical statisti-cal relationships between karstic denu-dation and a single climatic parameter (rainfall) are open to criticism: main authors tell that effective rainfall and pedological C02 are essential parame-ters of karstic denudation, which are never taken into account. For example, there are different PULINA's formula for different climatic types indicating that it is necessary to use another climatic parameter different from rain-fall! Moreover this way of modelling the data restrains the statistical repre-sentativity of each formula and intro-duces a difficult choice for karsts, which are at the border of two climatic types (or with mountainous parts). Another problem is the case of polar countries karsts where most precipitation is snowy and does not participate in karstic denudation. Therefore a mathematical modelling of carbonate dissolution is shown, based on infiltra-tion rate calculation and knowledge of calco-carbonic equilibrium. Temperature and rainfall are taken into account to determine the efficient part of precipitation, the productivity of pedogenetic C02 and the carbonate solubility constants. This theoretical approach gives the same results but with relative errors under 50 %. Consequently it is easy to compare different karstic countries in the world: hot and wet climates are confirmed to have the main karstogenetic activity but the role of cold countries is rehabilita-ted. Then paleokarstic denudation can be estimated.

Time patterns of karst denudation in northwest Georgia (U.S.A.) were investigated at three spring sites for 12 months and at five stream sites for 10 years. Rainfall was evenly distributed and showed no significant seasonality. At the springs, as well as the streams, water hardness was largely controlled by discharge. At the springs, Soil PCO2 and water pH were strongly correlated (r = -0.69 to -0.83). Solute transport in spring waters was highly seasonal, with two conduit flow springs removing more limestone in the winter, and the diffuse flow spring removing more during the growing season. At the stream sites, most denudation occurred during the winter and spring seasons, and least during the summer. Fourier analysis showed that variations in denudation occur on deterministic (long-wave) as well as stochastic (short-wave) time scales. As contributing variables, discharge varied in short-wave and long-wave cycles, whereas soil PCO2 showed only a long-wave cycle. The 12 month deterministic cycles were the most important, with changes in discharge taking precedence over Soil PCO2. Time series regression explains up to 69 per cent of changes in denudation through rain and soil pCO2. Time cycles in available water are the key controlling factor of denudation, and amounts of available Soil CO2 may not be as important in the temporal patterns of karst downwearing as has been believed previously

The Cayman Unconformity, which separates the Pedro Castle Formation (Pliocene) from the underlying Cayman Formation (Miocene), is a sequence boundary that developed during the Messinian, when sea level was at a lowstand due to glaciation in the Southern Hemisphere. By the end of the Messinian, Grand Cayman was an atoll-like island that had an elevated peripheral rim that was up to 41 m above the central depression. The Cayman Formation contains paleocaves and paleosinkholes that were linked to the Cayman Unconformity. The topography on the Cayman Unconformity is attributed to erosional processes, because (1) there is no evidence of carbonates that formed by constructional processes (i.e., reefs, dunes) in the elevated peripheral rim, and (2) there is ample evidence of dissolutional features in the Cayman Formation. The topography developed on the interior of Grand Cayman during the Messinian was uneven. A deep, basin-like depression, with its base as much as 50 m below the peripheral rim, formed on the western part of the island. By comparison, the floor of the depression on the eastern part of the island was 20-30 m higher. The difference in the topography, which is a reflection of the amount of bedrock dissolution, suggests that the effective rainfall was highest over the western part of the island. The relief on the Cayman Unconformity and associated structures shows that base level during the Messinian karst development was at least 41 m below present-day sea level. This is also provides an estimate of the Messinian lowstand position because the base level in oceanic karst settings is usually controlled by sea level

Karstification is a slow geodynamical process, controlled by the interaction between dissolution kinetics and flow dynamics. Moreover, mechanisms of network clogging by calcite precipitation or non-soluble clay accumulation are slow and continuous phenomena. This evolution of a karst system can be widely modified during exceptional rainfall episodes, such as the 22/09/92 storm (> 300 mm) near Vaison-la-Romaine. Such an impulse can modify the hydraulical behaviour of a massif, by unclogging the outlets of the saturated zone or the drainage network of the aquifer, and change hydrodynamical features of a spring (storage capacity etc.). This phenomenon has been demonstrated in a north Vaucluse karst aquifer whose recession coefficient has increased 7-fold and stored volume divided by 6

Rock salt is approximately 1000 times more soluble than limestone and thus displays high rates of geomorphic evolution. Cave stream channel profiles and downcutting rates were studied in the Mount Sedom salt diapir, Dead Sea rift valley, Israel. Although the area is very arid (mean annual rainfall approximate to 50 mm), the diapir contains extensive karst systems of Holocene age. In the standard cave profile a vertical shaft at the upstream end diverts water from a surface channel in anhydrite or elastic cap rocks into the subsurface route in the salt. Mass balance calculations in a sample cave passage yielded downcutting rates of 0.2 mm s(-1) during peak flood conditions, or about eight orders of magnitude higher than reported rates in any limestone cave streams. However, in the arid climate of Mount Sedom floods have a low recurrence interval with the consequence that long-term mean downcutting rates are lower: an average rate of 8.8 mm a(-1) was measured for the period 1986-1991 in the same sample passage. Quite independently, long-term mean rates of 6.2 mm a(-1) are deduced from C-14 ages of driftwood found in upper levels of 12 cave passages. These are at least three orders of magnitude higher than rates established for limestone caves. Salt cave passages develop in two main stages: (1) an early stage characterized by high downcutting rates into the rock salt bed, and steep passage gradients; (2) a mature stage characterized by lower downcutting rates, with establishment of a subhorizontal stream bed armoured with alluvial detritus. In this mature stage downcutting rates are controlled by the uplift rate of the Mount Sedom diapir and changes of the level of the Dead Sea. Passages may also aggrade. These fast-developing salt stream channels may serve as full-scale models for slower developing systems such as limestone canyons

A hydrogeological study was conducted, during the 1991-1992 water year, in the clay-soil mantled portion of a limestone terrain in southern Indiana. The purpose of the study was to investigate the modes of soil-water infiltration contributing to rapid transport of nitrate to the saturated zone. The I-year-cycle profiles of nitrate concentration vs. time show a consistent increase of nitrate at various depths in the unsaturated zone during the period of investigation. The increase of nitrate in soil water is attributed to the rapid flushing of the inorganic fertilizers from the fields after the area received sufficient rainfall in late fall. The investigation also showed a major movement of nitrate in quick pulses through the unsaturated zone, rather than a slow uniform recharge, immediately after a major storm event. The asymmetric profiles of nitrate concentration vs. depth point to the existence of preferential flow through macropores in the clay-soil mantle above the bedrock. Soil-water transport between storm events is by matrix type flow. Nitrogen isotopes were analyzed for representative groundwater samples collected before and immediately after fertilization of fields in the summer, 1991. The delta(15)N values of the samples did not show any major shift in nitrate sources between the sampling periods. The summer of 1991 was extremely dry prohibiting vertical transport of nitrate from the fields to the groundwater system. Any change in nitrate concentration in groundwater during this time is attributed to the mixing through lateral flow within the aquifer

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