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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 saturated is 1. referring to rock with water-filled voids. 2. referring to water which has dissolved as much limestone or other karst rock as it can under normal conditions [25].?

Checkout all 2699 terms in the KarstBase Glossary of Karst and Cave Terms

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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 rivers (Keyword) returned 155 results for the whole karstbase:
Showing 16 to 30 of 155
Palaeogeographic environment during the desiccation of the Black Sea, 1983, Kojumdgieva Emilia,
During the latest Chersonian (about 10.3 m.y. ago) tectonic movements took place leading to an elevation of the Crimean-Caucasian chain and to an isolation of the Fore-Caucasian part of the Black Sea Basin. This part of the basin had been draining the rivers of the Russian Platform and after the isolation it became desalinized, while the main part of the Black Sea Basin was almost desiccated and evaporites, mainly dolomites, formed in it due to the predominant calcium---magnesium---carbonate composition of the Chersonian Sea waters. These dolomites are found in the drillings of DSDP Leg 42B and are confirmed geophysically.The tectonic movements during the latest Chersonian led to the formation of a series of grabens along which the Mediterranean Sea invaded the north Aegean area and a little later (during the Early Maeotian) the Black Sea

Techniques gophysiques de type lectromagntiques appliques l'tude du karst nivernais, 1985, Couturaud A. , Benderitter Y.
STUDY OF KARSTIC DRAINS ENVIRONMENT BY GEOPHYSICAL TECHNIQUES (ELECTRIC AND ELECTROMAGNETIC) - Geophysical techniques (electric and electromagnetic) are tested on two underground rivers of the Nivernais karst (Bourgogne, France). The first site is an important dry valley and the second locates at the border of a plateau. No sharp image of the known galleries were obtained on both sites, but the first one shows a higher density of anomalies corresponding to the cave. In the axis of the valley is a weak resistivity anomaly, without any relation with the karstic drainage and which has not superficial origin. This anomaly would be the consequence of a fracturing of bottom valley. Others zones of fractures are evidenced, cross-cutting the conduits. The second one has also weak resistivity zones, independent of the cave, which are interpreted as annex system (hydrological sense). Some reflections on theoretical and methodological aspect of this type of research are proposed.

Quelques aspects du karst en Chine, 1985, Tricart, J.
Some characteristic features of karst in China Karst terrain is widespread in China: some 2,000,000km2, corresponding to 20-25% of the whole surface of the country. It occurs at very different altitudes and under quite different climates, from the region of Zhoukoudian, where has been found the skull of the Pekin Man, to the Tibet Plateau, where there is presently permafrost conditions, and up to southern tropical moist China, near Canton and Guilin. Recent chinese investigations have proved that most karst features are old. In Southern China a tropical karst (tower-karst or "mogotes" karst) is associated with lacustrine deposits containing the well-known Hipparion Fauna, of Miocene age. Its predates the intensive uplift of the Himalaya and of the Tibet, which has begun during the Pliocene and has continued during all the Pleistocene. The same fossils have been found in this tropical karst in present permafrost areas, above 5,000m. In the region of Guilin (Guangxi Province), this tropical karst has been described. There is evidence for the former existence of a covered karst, where limestones and dolomitic limestones were covered by a thick layer of reddish residual clays, with limonite. This mantle has been stripped during different periods of drier and probably cooler climate, has suggested by pollen spectra. In some places, these residual products have been trapped into pits, cracks, and caves. We have observed a small quantity of red clay painting limestone stalactites and sinters (Chuanshan and Leng Yin Yen Caves, in the surroundings of Guilin). They present sometimes a mining interest and some extractive industries are presently active (limonite, cassierite, etc.). Many caves have been surveyed by the Institute of Karst geology, in Guilin. Some have been equiped for tourism, around Guilin. All these caves are old. Some radiocarbon dating of speleothems yield ages of 33,000 year BP. The famous carving of the Leng Yen Cave have not been affected by calcite deposition from dripping since at least 500 years. The large caves that have been surveyed should correspond to a long evolution span. Along the Lijiang River, at least two terraces can be observed. They are built with gravels and pebbles, covered with thinner sand and loam, suggesting climatic changes, also attested by the changes of fauna and vegetation. These past cooler periods are characterised by an opened vegetation, with the striping of the old weathering cover of the former tropical karst. These karst terrains have been investigated in China for management purposes. Groundwater oscillations have frequently resulted in land subsidences damaging buildings, and in dramatic collapses destroying fields, roads. Sometimes, underground collapse plugged caves and dammed underground rivers, resulting in floodings. The caves are frequently used as reservoirs for irrigation and power plants.

Rotifer fauna in the periphyton of Karst rivers in Croatia, Yugoslavia, 1987, Erben R,

Le karst du massif des Calanques (Marseille Cassis), 1988, Blanc J. J. , Monjeau R.
THE KARST OF THE CALANQUES massif - Description of karstic morphology in relation to lithology and tectonic framework; actual hydrography. Sedimentary analysis applied to speleothems (calcitic deposits, hardened silts with rubefaction, upper stalagmitic layers, eolianites). Relations with some recent tectonic mechanisms. Hydrogeology: marine resurgences, subterranean rivers (Port-Miou and Le Bestouan).

Le massif de la Chartreuse, Alpes franaises du Nord : paysages karstiques et organisation des rseaux souterrains, 1990, Lismonde B. , Delannoy J. J.
The massif of Chartreuse: karsts features and underground systems (Alps, France) - The Chartreuse massif is the smallest of the subalpine massifs, but it contains the most important underground systems of French Alps. The massif of Chartreuse is characterised by parallel folds directed N020. The eastern plateau spreads out urgonian limestone (perched syncline); it contains the two largest cave systems: "Alpe-Alpette" (54 km) and "Dent de Crolles" (54 km). To the W, the limestone layers are uplifted by the orogenic strains and thereby, the caves are very deep: "rseau Ded" (- 780m), "puits Francis" (- 723m), "gouffre de Gnieux" (- 675m). Two transverse rivers make the hydrologic drainage: the "Guiers Vif" and the "Guiers Mort", which cut up the region into small hydrological basins. The greatest of them is "Guiers Vif" basin, with an area of 9.2 km2.

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.

A MIDDLE PROTEROZOIC PALEOKARST UNCONFORMITY AND ASSOCIATED SEDIMENTARY-ROCKS, ELU BASIN, NORTHWEST CANADA, 1991, Pelechaty S. M. , James N. P. , Kerans C. , Grotzinger J. P. ,
A major palaeokarst erosion surface is developed within the middle Proterozoic Elu Basin, northwestern Canada. This palaeokarst is named the sub-Kanuyak unconformity and truncates the Parry Bay Formation, a sequence of shallow-marine dolostones that were deposited within a north-facing carbonate platform under a semi-arid climate. The sub-Kanuyak unconformity exhibits up to 90 m of local relief, and also formed under semi-arid conditions when Parry Bay dolostones were subaerially exposed during a relative sea-level drop of about 180 m. Caves and various karren developed within the meteoric vadose and phreatic zones. Their geometry, size and orientation were largely controlled by northwest- and northeast-trending antecedent joints, bedding, and lithology. Near-surface caves later collapsed forming valleys, and intervening towers or walls, and plains. Minor terra rossa formed on top of highs. Karstification was most pronounced in southern parts of Bathurst Inlet but decreased northward, probably reflecting varying lengths of exposure time along a north-dipping slope. The Kanuyak Formation is up to 65 m thick, and partially covers the underlying palaeokarst. It consists of six lithofacies: (i) breccia formed during collapse of caves, as reworked collapse breccia and regolith; (ii) conglomerate representing gravel-dominated braided-fluvial deposits; (iii) sandstone deposited as braided-fluvial and storm-dominated lacustrine deposits; (iv) interbedded sandstone, siltstone and mudstone of sheet flood origin; (v) dolostones formed from dolocretes and quiet-water lacustrine deposits; and (vi) red-beds representing intertidal-marine mudflat deposits. Rivers flowed toward the northwest and northeast within karst valleys and caves; lakes were also situated within valleys; marine mudflat sediments completely cover the palaeokarst to the north. A regional correlation of the sub-Kanuyak unconformity with the intra-Greenhorn Lakes disconformity within the Coppermine homocline suggests that similar styles of karstification occurred over an extensive region. The Elu Basin palaeokarst, however, was developed more landward, and was exposed for a longer period of time than the Coppermine homocline palaeokarst

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.


Carbonate chemistry of surface waters in a temperate karst region: the southern Yorkshire Dales, UK, 1992, Pentecost Allan,
A detailed study of surface water chemistry is described from an important limestone region in northern England. Major ions and pH were determined for 485 sites (springs, seeps, streams, rivers and lakes) during summertime. The saturation state of the waters with respect to calcite was determined as the calcite saturation ratio ([Omega]). An unexpectedly large number of samples were found to be supersaturated (65.5% of the 268 km of watercourses surveyed). As a consequence, several streams entering major cave systems were incapable of further limestone solution, at least during periods of low flow. Many waters were supersaturated from their source and some deposited travertine. A significant negative correlation was found between spring discharge and both ([Omega]) and pH. Supersaturation was caused primarily by atmospheric degassing, with some contribution from aquatic plant photosynthesis.The median total dissolved inorganic carbon and Ca concentrations were 2.49 and 1.35 millimoles 1-1 respectively. Calcium originated exclusively from limestone, and carbon dioxide mainly from the soil and dissolved limestone. South facing catchments provided springwaters with significantly higher levels of TDIC and Ca when compared with north facing catchments. The study suggests that acid rain made a measurable contribution to limestone dissolution.Carboniferous limestone denudation rates were estimated as 54 to 63 m3 km-2 a-1 (54 to 63 mm 1000 years-1). About 50% of the Mg came from limestone and the remainder, together with most K, Na, SO4 and Cl from precipitation.Concentrations of dissolved nutrients were low, medians for NO3, NH4, total PO4 and SiO3 were 24 [mu]mol, 1.4 [mu]mol, 0.64 [mu]mol and 15.5 [mu]mol 1-1 respectively. The concentration of a further 23 trace elements was determined

Le gographe chinois Xu Xiake, un prcurseur de la karstologie et de la splologie, 1993, Cai Z. , Yang W. , Maire R.
Xu Xiake (1587-1641), the Chinese explorer and geographer, began in 1637 an astonishing four-year long journey in southwest China. Xu Xiake travels, written as a diary, is made up of 600 000 chinese letters: it is a geographical encyclopaedia belonging to the ancient masterpieces of China. Descriptions of the karstic geomorphology amount to more than 100 000 letters, that is to say the equivalent of 250 pages. He visited 288 karstic caves and described 22 types of karstic landforms. Xu Xiakes contribution to the study of the subterranean world is extremely valuable: deposits, underground rivers and lakes, climate, source of water, exploitation of the caves by humans and exploration techniques.

Rapports entre la karstification _primditerranenne et la crise de salinit messinienne, lexemple du karst lombard (Italie), 1994, Bini, A.
The Mediterraean dessiccation theory suggests that during the Messinian the Mediterranean sea lad almost completely dried up did a thick succession of evaporites was laid down Due to dessiccation the erosional base level through the whole Mediterranean area was lowered, with the consequent development of long and deep fluviatile canyons (e.g. Nile, Rhne, Var, etc). This lowering strongly affected karst evolution This paper concerns the karst in Lombardy, around the southalpine lakes. The old evolutionary models, predating dessiccation theory, assume that the lacustine valleys were scoured by the quaternary glaciers. ln this case the karst should have been characterized by some features, like for example the altitudinal cave distribution as a consequence of the valley lowering after each glaciation. Seismic experiments through the lakes and their tributaries have shown that these valleys are deep fluviatile canyons. The study of caves has demonstrated that the caves themselves predate the entrenchment of the valleys and the glaciations. During the latter the caves were filled up and emptied several times, without any modifications of their inner morphology, including stalactites. Moreover the U/Th age determinations indicate that a great number of concretions are older than 350 ky, and that a few are older than 1.5 Ma. As a conse-quence, a general model of karst evolution can be proposed. The former karstic drainage system developed after the Oligo-Miocene emersion. Paleogeography obviously diffe-red from the present day landscape but the main valley had already been scoured. During the Messinian the dramatic lowering of base level determined major changes in karstic evolution and a reorganisation of the karst drainage system that was consequently lowered considerably. The Pliocene transgression determined a new karst evolution, after which a great number of caves were located well below the sea level base. This evolution occurred during hot and wet climate period, with seasonal high flows and relevant discharges of the karstic rivers The great caves of the Lombardian karst developed within the climatic stage.

Nouveaux traages sur le massif de la Pierre Saint-Martin (Pyrnes-Atlantiques), 1994, Douat M. , Salomon J. N.
In 1982 and 1992 cavers observed the contamination of the B3 and Couey-Lotge underground rivers emerging at the Issaux springs This contamination was thought to be caused by the PSM water purificatlon station which discharges effluents into a fracture. The ARSIP and the LGPA laboratories were asked by the DDA (Pyrenees-Atlantiques administration) to carry out an hydrogeological study to prove the origin of this contamination and determine the limit of the Issaux catchment in the Guillers area in order to find a new site for a modern water purification station. Three uranine tracings were made (Water purification station - B3 underground river - BG. 106 shaft). The first two tracings emerged at the Issaux springs and the third tracing came out at the Bentia spring (Sainte-Engrace). These tracings confirm the hypothesis on the surficial basin limits between Issaux and Saint Vincent.

RELATIONSHIP BETWEEN FRACTURES AND KARSTIFICATION - THE OIL-BEARING PALEOKARST OF ROSPO MARE (ITALY), 1994, Soudet H. J. , Sorriaux P. , Rolando J. P. ,
The Rospo Mare oil field is located in the Adriatic Sea, 20 km off the Italian coast. The reservoir lies at a depth of 1300 m and consists of a paleokarst oi Oligocene to Miocene age which developed within Cretaceous limestones, now covered by 1200 m of Mio-Pliocene sequences. The oil column is about 140 m 8 high. The karstic nature of the reservoir was identified through vertical, cored drill holes which allowed us to analyse the various solution features and the sedimentary infilling (speleothems, terra rossa, marine clays), as well as their vertical distribution. Erosion morphology at the top of the karst is highly irregular, including in particular paleovalleys as well as many pit-shaped sink holes. Detailed geophysical knowledge of that morphology helped to optimize the development of the field through horizontal drilling. Observations concerning the upper part of the reservoir were compared to a palaeokarst of the same age, outcropping widely onshore, in quarries located nearby. The Rospo Mare paleokarst is an integral part of the ante Miocene paleokarst assemblages of the periphery of the Mediterranean which were formed in tropical conditions. Only the fractures enhanced by meteoric water during the formation of the karat are important for reservoir connectivity. During the formation of the karst there were several phases of dissolution and infilling which modified the geometry of the open fissures and only these fractures play an important role in the reservoir drainage. Vertically we can distinguish three very different zones from top to bottom: at the top the epikarst (0-35 m) in a zone of extension. All the fractures have been enlarged by dissolution but the amount of infilling by clay is substantial. The clays are derived either from alteration of the karat fabric or by deposition during the Miocene transgression; the percolation zone (15-45 m) is characterized by its network of large fractures vertically enlarged by dissolution which corresponds to the relict absorption zones in the paleokarst. These fractures, which usually have a pluridecametric spacing, connect the epi-karst with the former sub-horizontal river system. This zone has been intersected by the horizontal wells during the field development. In this zone there are local, horizontal barriers oi impermeable clay which can block vertical transmissibility. In these low permeability zones the vertical fractures have not been enlarged due to dissolution hence the horizontal barrier; the zone of underground rivers (35-70 m) is characterized by numerous horizontal galleries which housed the subterranean ground water circulation. When these fissures are plurimetric in extent this can lead to gallery collapse with the associated fill by rock fall breccia. This can partly block the river system but always leaves a higher zone of free circulation with high permeabilities of several hundreds of Darcys. These galleries form along the natural fracture system relative to the paleohydraulic gradient which in some cases has been preserved. The zone below permanent ground water level with no circulation of fluids is characterized by dissolution limited to non-connected vugs. Very locally these fissures can be enlarged by tectonic fractures which are non-connected and unimportant for reservoir drainage. Laterally, only the uppermost zone can be resolved by seismic imaging linked with horizontal well data (the wells are located at the top of the percolation zone). The Rospo Mare reservoir shows three distinct horizontal zones: a relict paleokarst plateau with a high index of open connected fractures, (area around the A and B platforms); a zone bordering the plateau (to the north-east of the plateau zone) very karstified but intensely infilled by cap rock shales (Miocene - Oligocene age); a zone of intensely disturbed and irregular karst paleotopography which has been totally infilled by shales. The performance of the production wells is dependent on their position with respect to the three zones noted above and their distance from local irregularities in the karst paleotopography (dolines, paleovalleys)

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.


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