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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 acoustic resistance is the product of wave velocity and rock density indicating the reflective power of a boundary between two strata [16].?

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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 snow (Keyword) returned 57 results for the whole karstbase:
Showing 1 to 15 of 57
Snow in Eldon Hole, Derbyshire, 1947, Pill A. L.

Observations at the Blue Waterholes, March 1965 - April 1969, and Limestone Solution on Cooleman Plain, N.S.W., 1972, Jennings, J. N.

After brief descriptions of the geomorphology of the Cooleman Plain karst and in particular of the Blue Waterholes, the methods adopted to analyse the functioning of these major risings are detailed. The discharge regime of Cave Creek below them is oceanic pluvial in type perturbed by drought and snow. There is much annual variation both in seasonal incidence and total amount, with catchment efficiency correspondingly variable. Suspended sediment concentration is even more erratic and monthly determinations are inadequate for calculating corrasional denudation rates. Mean concentrations of suspended solids are about 1/18th of solute load. Total dissolved salts have a strong inverse relationship with discharge, and mean values are high compared with those for other catchments in eastern Australia but none of these determinations are from limestone catchments. Sodium, potassium, and chlorine contents are low compared with the same catchments but silica is relatively high. The ratio of alkaline earths to alkalis indicate that Cave Creek carries carbonate waters and there is an inverse regression of the ratio on discharge. There is inverse correlation of total hardness on discharge likewise due to concentration of surface waters by evaporation in dry periods, together with reduced underground solution rate at times of large, rapid flow. The spring waters remain aggressive. Close regressions of hardness on specific conductivity now permit the latter to be determined in the place of the former. Much evidence converges to indicate that all the springs at the Blue Waterholes are fed from the same conduit. The intermittent flow which comes down the North Branch on the surface to the Blue Waterholes differs significantly in many characters from the spring waters. Rates of Ca + M carbonate equivalent removal vary directly with discharge since hardness varies much less than does water volume. These gross rates have to be adjusted for (a) atmospheric salts entering the karst directly, (b) peripheral solute inputs from the non-karst two-thirds of the catchment and (c) subjacent karst solution before they can be taken as a measure of exposed karst denudation. The methods for achieving this are set out. The total corrections amount to about one third of the total hardness, though the correction for subjacent karst on its own lies within the experimental error of the investigation. The residual rate of limestone removal from the exposed karst also shows a winter/spring high rate and a summer/autumn low rate but the seasonal incidence and annual total varied very much from year to year. In comparison with results from karsts in broadly similar climate, the seasonal rhythm conforms and so does the high proportion (78%) of the solution taking place at or close to the surface. This reduces the importance of the impounded condition of this small karst but supports the use of karst denudation rate as a measure of surface lowering. Cave passage solution may however be more important in impounded karst than its absolute contribution might suggest, by promoting rapid development of underground circulation. The mean value of limestone removal is low for the climatic type and this is probably due to high evapotranspirational loss as well as to the process of eliminating atmospheric, peripheral non-karst and subjacent karst contributions. The difficulties of applying modern solution removal rate to the historical geomorphology of this karst are made evident; at the same time even crude extrapolations are shown to isolate problems valuably.

Paleohydrology and Streamflow Simulation of three Karst Basins in Southeastern West Virginia, U.S.A., PhD Thesis, 1975, Coward, Julian Michael Henry

This study was undertaken to gain a better understanding of karst hydrology. To do this, the present day hydrology and the paleohydrology were determined in three karst basins. The basins chosen were the Swago, Locust and Spring Creek basins in Pocahontas and Greenbrier Counties, West Virginia. A number of conventional field techniques were used successfully in this study, including the following: current meter and dye dilution gauging; dye and lycopodium stream tracing; geological and cave mapping; the setting up of stage recorders; geochemistry; and limestone erosion measurements. The climate of the region was investigated to obtain realistic precipitation, temperature and potential evaporation data over the study basins.
It was found that the mean precipitation over two of the basins was 30% higher than recorded data in the valleys. The karst development of the basins was found to take place in four major stages. These were: A) initial surficial flow, B) strike controlled drainage, C) major piracies from one sub-basin to another, and D) shortening of the flow routes. The major controls on the karst development were found to be: A) the Taggard shale, B) the strike direction, which controlled early basin development, and C) the hydraulic gradient from the sink to rising, which controlled later basin development.
To better assess the quantitative hydrology, and to assist in determining the type of unexplorable flow paths, a watershed model was developed. This modelled the streamflow from known climatic inputs using a number of measured or optimized parameters. The simulation model handled snowmelt, interception, infiltration, interflow, baseflow, overland flow, channel routing, and evaporation from the interception, soil water, ground water, snowpack and channel water. The modelled basin could be split up into 20 segments, each with different hydrological characteristics, but a maximum of 3 segments was used in this study.
A total of 29 parameters was used in the model although only 10 (other than those directly measurable) were found to be sensitive in the three basins. The simulated streamflow did not match the real flows very well due to errors in the data input and due to simplifications in the model. It was found, however, that as the proportion of the limestone in a segment increased the overland flow decreased, the interflow increased, the baseflow and interflow recessions were faster, the soil storages were smaller and the infiltration rate was higher, than in segments with a larger proportion of exposed clastics. The flow characteristics of the inaccessible conduits were inferred from the channel routing parameters and it was postulated that the majority of the underground flow in the karst basins was taking place under vadose conditions.

Un exemple de karst haut-alpin : le Dsert de Plat (Haute-Savoie), 1984, Maire, R.
AN EXAMPLE OF HIGH ALPINE KARST: THE DSERT DE PLAT (HAUTE-SAVOIE) - Situated in the French Northern Alps between 1600m and 2800m elevation, the Dsert de Plat is characterised by a wet, cold and very snowy climate (P = 2400-2800 mm/year). We observe several morphoclimatic levels: the upper mountain karst (1500-1700m), the subalpine karst (1700-1950m), the alpine karst (1950 - 2600m) and the proglacial karst (well developed in the Haut-Giffre massif. Glacio-karstic landforms like cirque-dolines and pavements (Schichttreppenkarst) are inherited from the quaternary glaciations. The deep karst underlines the part of quaternary climatic sequence with complex drainage and fillings. Now, the karstic flow is a nival type (maximum during the spring and summer minimum) but the hydrochemical cycles are opposite (spring minimum). Nevertheless, because of a very abundant underground discharge during hot season (80%), the exported limestone reaches 75% of annual amount. The specific dissolution is strong (104 mm/ky), but it does not reach the optimum of forest mountain karst, like Vercors (120-170mm/ky).

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).

Approche gomorphologique des karsts du gypse de la Vanoise (la zone alpine et glaciaire du vallon du Fruit-Gbroulaz,Alpes), 1991, Chardon, M.
GYPSUM KARSTIC LANDFORMS IN VANOISE: the alpine and glacial valley of Vallon du Fruit-Gbroulaz (Alps, France) - In the inner part of the northern french Alps, the higher regions of the Vanoise offer outcrops of Triassic gypsum of which the surface and thickness vary. In the vallon du Fruit, the Gbroulaz glacier partially covers a long strip of gypsum, which reaches its highest point at the Roc de la Soufrire (2940 m). Rivers and springs in the vallon du Fruit are fed both by sub-aerial glacial outflows and by karstic underground flows, which are pro-glacial and sub-glacial. A very low chemical dissolution exists under the glacier and along the fast pro-glacial underground and sub-aerial flows, whereas the rate of karstic denudation is high in the margin of the glacier where it reaches 1500 mm/ky at around 2500m (1 ky = 1000 years). The formation and evolution of the dolines is rapid and occurs through underground sucking and dissolution once the area is deglaciated, thanks to underground active flows fed by the glacier and snow melting. Gypsum domes are uplifted under the effects of neotectonic movements and postglacial decompression brings about considerable superficial fissuring because of the elasticity of the rock. Over 10,000 years, the morphogenesis of these domes in the humid and cold climatic conditions of these high alpine mountains has transformed them into perforated ladle and domes. Small outcrops are changed into monoliths or gypsum inselberg. A model of the geomorphologic post-glacial evolution of these domes, over some 20,000 years, is proposed.

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

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.

Signification des remplissages des karsts de montagne, quelques cls lusage des splologues, 1995, Audra, P.
This paper is intended to cavers in order to help them identify the most significant mountain karst infillings. Carbonated varves sedimentation occurs during floodings in glacial environment. The varves block the deep parts of the networks. Pebbles sealings show a powerful erosion in the vadose zone, near glacial sinkholes. Gelifract spreadings are indicators of frost and snow action in periglacial environment. Reworked weathered rocks are the most ancient deposits, inherited from tertiary warm phases when karstification occurred under regolith covers. Their clearing is partly simultaneous with cave systems elaboration, in relation to the alpine uplift, during Pliocene. Speleothems are also warm or temperate climate indicators. Crystalline morphology reflects environmental characteristics, while their surface sight could have been smoothed during discharge reactivations. Finally, some infillings could have recorded neotectonic movements: broken speleothems, deformed clastic sediments, etc.

The discharge variability of some karst springs in Bulgaria has been investigated in detail within a region situated in the semiarid zone where most of the principal processes controlling spring outflow (evapotranspiration, snow accumulation, karstic functioning) are significant. While the karstification was notable in the Kotel and Bistretz springs with a predominance of quickflow, in the Beden system the baseflow was higher and had a behaviour similar to a porous aquifer. Univariate and bivariate spectral analyses were applied as a suitable tool in preparation for a further application of precipitation-discharge relationship models

Contribution to geomorphological and hydrogeological study of karst in Mediterranean environment: the Aït Abdi plateau (central limestone High Atlas, Maroc),PhD thesis, 1995, Perritaz, L.

The Ait Abdi karstic plateau is located in the heart of the calcareous High Atlas (32°N/6°W). With an area of 160 km2, it is situated between 2,200 and 3,000 meters above sea level, i.e. 800 meters above the nearest valleys and canyons. It consists of a large series of massive Bajocian limestones which form a large brachysyncline, the axial plane of which dips gently to the NE. These limestones overlie a thick series of Toarcian-Aalenian detritic sediments forming the regional aquiclude and the top of the half captive Middle Liasic aquifer. The plateau is limited both in the N and S by strong changes in dip to the vertical of the sedimentary layers (ejective thrusted anticlines), and in the W and E by deep canyons created by major rivers. Therefore the plateau is a totally isolated calcareous compartment, from both a morphologic and a hydrogeologic point of view.
The climate of this region is Mediterranean with an altitude modification: maximum rainfall occurs in winter and in spring, snow cover is not durable but sometimes important, storms are common for dry season in summer. The precipitations comprise only 500 to 700 mm/year (subhumide zone) and the effective evapotranspiration is approximately 400 mm/year, including the losses due to sublimation. The snow coefficient is 60 %. This means that the recharge of the aquifer, occurring almost entirely during snow melting, is limited, but the large bare surfaces of the plateau with typical well developed karst forms (dolines, poljes, dry valleys, holes) improve the infiltration rate (40%). The specific discharge is only 8.1 L/s/km2.
The morphologic peculiarity of this nival karst consist of a succession of small parallel and asymmetric dry valleys forming some "waves". For that reason, the French geomorphologist Couvreur termed these climate controlled features "karst en vagues". The role of wind and snow in the genesis of these forms is predominant. The most of time structure controlled plateau's poljes are quasi inactive today. All kinds of high mountain karren landforms are present on the plateau and prove the great role of snow role in the microforms genesis.
An ancient speleological network with vertical shafts occluded lower down suggest of ancient more humid climatic conditions. U-Th dating indicates ages between 3,200 and 220,000 years, or outside the range of the method (more than 400,000 years). The lateral flow is conducted by an interstrata network, inactive and dry in the upper part, or active and phreatic at the base, near the regional aquiclude, attesting three karstification phases.
The water discharges as typically karstic hillfoot springs, most of the time oversaturated and forming tufas. Large doleritic vertical dykes cut the plateau and form major drainpipes. The physical-chemical and chemical signature of these spring waters is quite different of the signature of other springs of this area, which discharge whether from small local Toarcian-Aalenian aquifers or from the huge semi confined karstic Middle Liasic aquifer. The plateau springs hydrodynamic response is characteristic for an elevated karstic aquifer with rapid flow. The aquifer geometry does not allow important reserves, but the mean discharge from all perennial springs (about 1 m3/s) is a precious resource for the population of this far area of the Atlas Mountains.

Le karst en vagues des At Abdi (Haut-Atlas central, Maroc), 1996, Perritaz, L.
The At Abdi plateau (2200-3000 m, 160 km2) is located in the calcareous High Atlas (32? N). It consists of massive Bajocian limestones, which form a large brachysyncline and overlie the clastic Toarcian-Aalenian forming the regional aquiclude and the top of the half captive Middle Liassic aquifer. The rainfall comprises only 500 to 700 mm/yr and the effective evapotranspiration is about 400 mm/yr with a snow coefficient of 60 % and an infiltration rate of 40 %. This means that the recharge of the aquifer mainly occurs during snow melting. The morphology of this nival karst consists in a succession of little parallel and asymmetric dry valleys forming some "waves" ("karst en vagues"). The role of wind and snow in the genesis of these forms is predominant. An old cave system with vertical shafts occluded lower down is proof of ancient more humid climatic conditions. U-Th dating methods on speleothems indicate ages between 3,200 and 220,000 yrs, or more than 400,000 yrs. The horizontal transfer is made by an interstrata network, ancient and dry in the upper part, or recent and phreatic at the base, near the regional aquiclude, attesting three karstification phases.

The governing factors of the physicochemical characteristics of Sheshpeer karst springs, Iran, 1996, Raeisi E. , Karami G. ,
The physical and chemical characteristics of karst springs are not a sole function of flow path in the carbonatic rock mass. A number of other parameters, including the type of precipitation, soil cover morphology of the exposed area, and the hydrochemistry of the infiltrating water into the karst system also have their own contribution. In the present study, the Car and Barm-Firooz mountains me chosen to determine some of the governing factors of the physical and hydrochemical characteristics of karst springs. The following measurements were carried out: 1. Concentration of major ions and electrical conductivity of the fresh snow and snowpack. 2. Variation of discharge as a function of time at six sicking streams. 3. Time Variation of discharge, electrical conductivity, and air and water temperature of sinking streams at seven sinkholes. 4. Electrical conductivity and temperature of water at the surface and 40 cm beneath the soil cover. 5. Discharge, major ions, temperature and electrical conductivity of the Sheshpeer spring water were measured every twenty days for a period of three years. The results indicate that if the physical and chemical characteristics of a karst spring are going to be used to determine the characteristics of corresponding aquifer, first the effect of external factors on the outflow should be accounted for, and then the characteristics of the karst aquifer be determined

Karst and hydrogeology of Lebanon, 1997, Edgell Hs,
Karst is very well-developed in Lebanon in thick, exposed, fractured and folded Jurassic, Cretaceous, and Eocene carbonates, as well as in localized, coastal Miocene limestones. This karstification not only results from the predominant calcareous lithology, but is also caused by the high, northerly trending ranges of he country, which cause abundant precipitation, as heavy rain and thick snow, to fall on Mt. Lebanon, Jabal Barouk, Jabal Niha, and Mt. Hermon. Lesser amounts fall on the Anti-Lebanon, Beqa'a Valley and the coastal hills of the country. Some 80% of precipitation occurs from November through February. The karst water emerges from five first-magnitude springs (Ain ez Zarqa (11 m(3)/sec), Ain Anjar (max. 10m(3)/sec), Nabaa Ouazzani (max. 6m(3)/sec), Nabaa Arbaain (mau. 3 m(3)/sec) and Nabaa Barouk (max. 3m(3)/sec), plus hundreds of second-and third-magnitude springs, and thousands of smaller springs. The large springs are all karstic and contribute to 13 perennial springs in the main Lebanese ranges, and 2 in the Anti-Lebanon. These include major rivers, such as the Nahr el Litani, Nahr el Assi (Orontes) and Nabr el Hasbani (upper Jordan River). More than two-thirds of the area of Lebanon (i.e. 6900 km(2)) is karstified and includes surface karst features, such as poljes, uvalas, dolines, blind valleys, natural bridges, and ponors, as well as smaller features, like karren and hoodoos. Subsurface karst features include many types of solutional shafts and galleries, grottoes, subsurface lakes and rivers and most types of speleothems. There are at least 15 aquifers in Lebanon, of which 14 are in karstified carbonate strata. The 1700m thick limestone/dolomite core of the ranges and over 2000m thickness of flanking, or overlying, Cretaceous limestones provide the majority of these aquifers, while significant aquifers are also found in thick Eocene limestones. High transmissivity values (T = or > 1.83 x 10(-1) m(2)) occur in these karstic aquifers, as is shown by the rapid decline in spring flow over the dry summer and autumn months, and their very quick recharge by winter and spring rains and heavy snow on the Lebanese ranges

Gypsum Trays in Torgac Cave, New Mexico, 1998, Doran, L. M. , Hill, C. A.
Mount St. Helens is an active dacitic volcano, which is currently in a semi-dormant state after a catastrophic explosive eruption in May 1980. A dacite dome occupies the crater and plugs the volcanic vent. The crater area has been progressively covered by a layer of snow, firn, and glacier ice since as early as 1986. Heat, steam, and volcanic gases from the crater fumaroles melted over 2415 meters of cave passage in the crater ice mass. The caves are in approximate balance with the present geothermal heat release. Future changes in the thermal activity will influence the dimensions, location, ceiling, wall, and wall ablation features of these caves. Cave passages are located above fumaroles and fractures in and adjacent to the crater lava dome. Cave passages gradually enlarge by ablation, caused by outside air circulation and by geothermal sources beneath the ice. The passages form a circumferential pattern around the dome, with entrance passages on the dome flanks. Passages grow laterally and vertically toward the surface, spawning ceiling collapse.

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