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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. ...

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That capacity, carrying is the capacity of a watercourse to transport solids [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 glaciers (Keyword) returned 45 results for the whole karstbase:
Showing 1 to 15 of 45
Speleothems and paleoglaciers, , Spotl Christoph, Mangini Augusto,
Ice and speleothems are widely regarded as mutually exclusive as the presence of liquid water is a fundamental prerequisite for speleothem deposition. Here we show that speleothems may form in caves overlain by a glacier, as long as the temperature in the cave is above freezing and the conduits are not completely flooded by melt water. Carbonate dissolution is accomplished via sulfide oxidation and the resultant speleothems show high [delta]13C values approaching and locally exceeding those of the parent host rock (lack of soil-derived biogenic C). The [delta]18O values reflect the isotopic composition of the melt water percolating into the karst fissure network and carry an atmospheric (temperature) signal, which is distinctly lower than those of speleothems formed during periods when soil and vegetation were present above the cave. These `subglacial' speleothems provide a means of identifying and dating the former presence of warm-based paleoglaciers and allow us to place some constraints on paleotemperature changes

Ecology, systematics and distribution of two sympatric in North-Germany living Bathynella species (Crustacea, Syncarida)., 1968, Husmann Siegfried
The sympatric occurrence of two bathynellids previously considered races of Bathynella natans; natans and stammeri; is evaluated as a natural ecological-genetic experiment. Since no hybrids appear in mixed populations, these forms are proven to be full species: Bathynella natans Vejdovsky and Bathynella stammeri (Jakobi). Besides the form of the mandibles, which until now was the only taxonomically useful diagnostic character in the genus Bathynella, 7 additional, suitably applicable morphological characters have been found (Table 3). The Bathynella biotope investigated is assigned to the "eustygopsammal" subterranean life province (Husmann 1966), which is associated with the "Parastenocaris-Bathynella" biocoenosis (Husmann 1962). This particular biocoenosis is evidently resistant to organic pollution of ground water. The sympatric existence of Bathynella natans and B.stammeri can be explained by consideration of the geo-limnological developmental history of the interstitial zone of the North German low plain. Sands and gravels were widely deposited in the North German Basin by northward-retreating glaciers, creating microcavernous living space and passages for the interstitial fauna. This microfauna could find passages in layers of sand under and along the northward-flowing streams. Primitive Ice-Age streams (,,Urstromtler" of Keilhack) formed east-to-west cross-connections between the south-north distributional corridors. The great geographical expansion of the tributary river courses which reached the north German plain before, during, and after the Ice Age suggests that ground water habitats were temporarily separated and later rejoined by orogenic movements of the earth's surface. Such an orogenically caused, geomorphological isolation lasting for a sufficiently long geological period could have led to the result that species, originating in isolation from the same phylogenetic stock, subsequently were brought together again in the same biotope. This is particularly true for bathynellids, which as archaic types (Lebensformtypen) of the ancient, extreme "mesopsammal" biotope (Remane) are quite likely to have become sympatric in such a manner.

Ecology, systematics and distribution of two sympatric in North-Germany living Bathynella species (Crustacea, Syncarida)., 1968, Husmann Siegfried
The sympatric occurrence of two bathynellids previously considered races of Bathynella natans; natans and stammeri; is evaluated as a natural ecological-genetic experiment. Since no hybrids appear in mixed populations, these forms are proven to be full species: Bathynella natans Vejdovsky and Bathynella stammeri (Jakobi). Besides the form of the mandibles, which until now was the only taxonomically useful diagnostic character in the genus Bathynella, 7 additional, suitably applicable morphological characters have been found (Table 3). The Bathynella biotope investigated is assigned to the "eustygopsammal" subterranean life province (Husmann 1966), which is associated with the "Parastenocaris-Bathynella" biocoenosis (Husmann 1962). This particular biocoenosis is evidently resistant to organic pollution of ground water. The sympatric existence of Bathynella natans and B.stammeri can be explained by consideration of the geo-limnological developmental history of the interstitial zone of the North German low plain. Sands and gravels were widely deposited in the North German Basin by northward-retreating glaciers, creating microcavernous living space and passages for the interstitial fauna. This microfauna could find passages in layers of sand under and along the northward-flowing streams. Primitive Ice-Age streams (,,Urstromtler" of Keilhack) formed east-to-west cross-connections between the south-north distributional corridors. The great geographical expansion of the tributary river courses which reached the north German plain before, during, and after the Ice Age suggests that ground water habitats were temporarily separated and later rejoined by orogenic movements of the earth's surface. Such an orogenically caused, geomorphological isolation lasting for a sufficiently long geological period could have led to the result that species, originating in isolation from the same phylogenetic stock, subsequently were brought together again in the same biotope. This is particularly true for bathynellids, which as archaic types (Lebensformtypen) of the ancient, extreme "mesopsammal" biotope (Remane) are quite likely to have become sympatric in such a manner.

A possible mechanism for growth of calcite speleothems without participation of biogenic carbon dioxide, 1982, Dreybrodt W,
Using Plummer et al.'s [11] rate equations on the dissolution and deposition of CaCO3 in H2O---CO2 systems, we have calculated deposition rates of CaCO3 to stalagmites in caves which are covered by glaciers or bare karst. In this case no biogenic CO2 from vegetated soil is available and the deposition of CaCO3 involves only atmospheric CO2. The mechanism of deposition proceeds by a temperature effect. Cold melting waters of about 0[deg]C dissolve CaCO3 under open system conditions at the surface of the rock. When this solution saturated with respect to CaCO3, flows through the limestone rock its temperature increases by several degrees. Therefore, it becomes supersaturated, and CaCO3 is deposited under open system conditions in the warmer cave. Maximal growth rates of about 10-3 cm/year are possible. From the kinetics of the deposition of CaCO3 from the thin water films present at the surface of stalagmites we are able to estimate the isotopic composition of carbon in the CaCO3 deposited on the stalagmites to be approximately [delta]13C = %, which is close to some observed values.From our data we conclude that substantial growth of stalagmites is possible during glacial periods as well as in areas of bare karst, a question which was not resolved up to now

Le systme souterrain du Sornin (Berger-Fromagre, Vercors, Isre), 1983, Delannoy, J. J.
THE UNDERGROUND SYSTEM OF PLATEAU DU SORNIN (VERCORS, FRANCE): THE GOUFFRE BERGER AND THE SCIALET DE LA FROMAGERE - Gouffre Berger (-1198m) and Scialet de La Fromagre (-902m) are the two main drains of an important underground complex, which develops 26 km inside Sornin table-land, massif du Vercors, Isre. The glaciers have left deep prints in the surface morphology (Schichttreppenkarst) and have played an important role in the genesis of the underground complex of Sornin. Most of morphological elements and dated witnesses (speleothems) testify to the primacy of this morphoclimatic term. Under present bioclimatic conditions (discontinuous forest - Raw weather climate, T? = 4?C, P = 1700mm), the specific dissolution is estimated to 120mm/ky. This dissolution is important in winter (2,5 times more than in summer). Sornin plateau belongs to an intermediary case between forests mountainous karsts and high karsts regarding the spatial distribution of the dissolution.

Carte hydrogomorphologique, hydrogologie et hydrochimie du karst de Dorvan (Ain), 1983, Gibert J. , Laurent R. , Maire R.
PRESENTATION OF THE HYDROGEOMORPHOLOGICAL MAP AT 1/100,000 ON KARST OF DORVAN (SOUTHERN JURA, AIN, FRANCE. Main researches about hydrology and hydrochemistry on this karst - The Dorvan massif is a low mountain Jurassian karst with a wet temperate climate and a little nival influence. The surface relief is covered with important decalcification clay. The drainage of the karst is assumed by superimposed systems, according to the excavation of the Torcieu watergap. The flow of the main outlet (Pissoir) is a pluvial type, which presents an annual cycle with a maximum in winter and a minimum in summer. The specific discharge is 31.4 l/s/km2. The dissolution rate is high: 81 mm/ky. 50% of the corrosion interests the epikarst, 50% interests the endokarst. During the Pleistocene, the glaciations played a direct or indirect role on the evolution of the Dorvan karst: nivo-karst during the Wrm; fluvio-glacial up-building of the Torcieu watergap and correlated water logging of the lower karst during Wrm and Tardiglacial periods; probable direct action of glaciers during the Riss.

Le rle des hritages quaternaires dans les karsts alpins : le cas des Alpes du Nord, 1984, Chardon, M.
THE PART OF THE QUATERNARY INHERITED FEATURES IN THE ALPINE KARSTS: THE EXAMPLE OF THE NORTHERN ALPS - In the western part of the Alps, limestone mountains have been built mainly during Miocene and Pliocene. The relicts of pre-quaternary alterations or karstifications are scarce and difficult to identify. The most part of the morphological features can be related to the quaternary glacial stages. The main landforms of the high and low alpine mountains are described. The glaciers and their melting waters have excavated deep gorges-valley and caves.

Le systme souterrain de la Dent de Crolles, Isre, 1985, Marchand, Th.
THE UNDERGROUND SYSTEM OF DENT DE CROLLES (ISERE, FRANCE) - The Dent de Crolles plateau (highest point: 2062m asl.) is the southermost part of the great syncline of the eastern Chartreuse. This syncline stretches from Grenoble to Mont Granier, above Chambery. The karst of Dent de Crolles develops in urgonian limestone, and in spite of little surface (2km2), it contains the most important underground system of the French Alps (about 52km). In spite of important oceanic rainfall, underground flows only drain some small galleries. Karst genesis is related to the glaciers.

Les karsts de l'avant-pays alpin au nord des Alpes occidentales, 1989, Chardon, M.
Karsts of the alpine foreland north to the French Western Alps: glacial origin of the underground systems - Karstic mountains are described between Rhne valley and the border of Northern Alps. The influence of quaternary glaciers is evident for surface landforms and the existence of inactive canyons can be explained only by glacial outflows. Large underground caves and systems such as La Balme, Les Echelles, contain numerous blocks and pebbles of alpine rocks. Except in some places of the alpine mountains, the pre-quaternary karstic evolution cannot be investigated. Now the rate of karstic corrosion is too low and waters are unable to produce large caves. Only the mechanical action of whirling glacial flows in some pre-determinated places can explain the presence of large caves in these low karstic mountains. The formation of these kind of caves can be correlated with the existence of the actual canyons and defils along this part of the Rhne river.

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.

Karstification et volution palogographique du Jura, 1991, Bienfait, P.
KARSTIFICATION AND PALEOGEOGRAPHICAL EVOLUTION OF THE JURA (Fr.) - The karstification started at the beginning of the Tertiary, and the process is still going on today. During the Eocene, modifications brought about under the tropical climate resulted in siderolithic deposits (siliceous sands, ferruginous soils), which can be found in some fossil karsts. In the Oligocene, active tectonics modified the Eocene surface. Erosion during the Miocene levelled the Jura Mountains into a peneplain even though the climate remained tropical. Toward the end of the Miocene, present-day structure and landforms were produced when the main folding, subjected at the same time to powerful erosion, occurred. During the Upper Pleistocene the climate became cooler and wetter. At least two glacial periods have been recognised in the Pleistocene. Present-day karst landforms and most of the caves can be considered as being shaped during the Plio-Quaternary. The karst fillings of the Quaternary provide evidence of the extension of the Wrm and Riss glaciers.

STABLE ISOTOPIC COMPOSITION OF METEORIC CALCITES - EVIDENCE FOR EARLY MISSISSIPPIAN CLIMATE-CHANGE IN THE MISSION CANYON FORMATION, MONTANA, 1993, Smith T. M. , Dorobek S. L. ,
The Lower Mississippian Mission Canyon Formation of central to southwestern Montana was deposited under dominantly semiarid to arid climatic conditions during Osagean to early Meramecian times. Following deposition, a pronounced climatic shift to more humid conditions occurred during middle Meramecian times. This climatic change is indicated by extensive, post-depositional karst fabrics and in the stable isotopic composition of early, meteoric calcite cements and diagenetically altered sediments. Early meteoric calcite cement in Mission Canyon limestones is generally nonluminescent and fills intergranular and fenestral porosity. Petrographic data indicate that this cement formed during intermittent subaerial exposure of the Mission Canyon platform during Osagean times. This initial generation of meteoric calcite cement has deltaO-18 values from -8.1 to -2.6 parts per thousand PDB. These data, and the oxygen isotopic values from nonluminescent skeletal grains and micrite in host limestone indicate that Osagean meteoric water may have had deltaO-18 values as low as -6.0 parts per thousand SMOW. A second generation of petrographically similar, but isotopically distinct, calcite cement fills biomolds and porosity within solution-collapse breccias in the Mission Canyon Formation. This cement generation postdates earlier nonluminescent Osagean calcite cement and is volumetrically most abundant near the top of the Mission Canyon Formation. DeltaO-18 values from these cements and from nonluminescent lime mudstone clasts and matrix in solution collapse breccias range from -13.8 to -8.2 parts per thousand PDB. These data indicate that Meramecian meteoric water may have had deltaO-18 values as low as - 12.0 parts per thousand. However, a higher-temperature burial overprint on the deltaO-18 values of the calcite cement cannot be ruled out. The more positive deltaO-18 values of the Osagean calcite components probably indicate warm and arid conditions during short-term [10(4)(?) yr) subaerial exposure along intraformational sequence and parasequence boundaries. The more negative deltaO-18 values from Meramecian calcite components and the extensive karst associated with the post-Mission Canyon unconformity may have developed because of cooler and more humid climatic conditions and possible rain-out effects during middle Meramecian times. A dramatic shift towards cooler and more humid climatic conditions may be coincident with the onset of major continental glaciation in the Early Carboniferous. The post-Mission Canyon unconformity has been attributed to a major fall in sea level that may have glacio-eustatic origins. Growth of continental glaciers during a time of global cooling would have caused migration of polar fronts further toward the paleoequator. These polar fronts in turn, would have pushed moist, mid-latitude weather systems toward the paleoequator, resulting in cooler, more humid conditions in low-latitude settings during ''icehouse'' times

Alpine karsts. Genesis of large subterranean networks. Examples : the Tennengebirge (Austria) - the Ile de Crémieu, the Chartreuse and the Vercors (France), PhD Thesis, 1993, Audra, Philippe

This work, based on the study of several underground alpine networks, aims to propose some milestone in the history of these karstic regions.

The first part of the work is made up of three regional studies.

The Tennengebirge mountains are a massif of the limestone High Alps in the region of Salzburg in Austria. A cone karst close to the base level developed in the Neogene. Streams from the Alps fed the karst, resulting in the huge horizontal networks of which the Eisriesenwelt provides evidence. During the successive phases of upthrust, the levels of karstification, whether on the surface or deeper down, settled into a tier pattern, thus descending in stages from the base level. From the Pliocene era onwards, thanks to an increase in potential, alpine shafts replace the horizontal networks. The formation of these shafts is more pronounced during glaciation. The study of the Cosa Nostra - Bergerhöhle system developing 30 km of conduits on a gradient reaching almost 1 500 m provides a fairly full view of the karstification of this massif. It includes the horizontal levels developed in the Miocene and the Plio-Pleistocene, joined together by vertical sections. The most noteworthy features of the Tennengebirge, as in the neighboring massifs, lie first and foremost in the extreme thickness of the limestone which has recorded and immunized the differents steps of karstification. Secondly, the size of the networks can be, for the most part, accounted for by the contribution of allogenous waters from the streams of the Neogene and the glaciers of the Pleistocene. Generally sudden and unexpected, these flows of water engendered heavy loads (up to 600 m), simultaneously flooding several levels. To a lesser extent, the situation is similar today.

The Ile de Cremieu is a low limestone plateau on the western edge of the Jura. Due to its location in the foothills, the lobes of the Rhône glacier have covered it up, obliterating the surface karst. However, widespread evidence of anteglacial morphologies remains : paleokarst, cone karst, polygenic surface. Because of glacial plugging, access to the underground karst is limited. The main cavity is the cave of La Balme. Its initial development dates back to an early period. The morphological study has permitted the identification of several phases which go back to the Pleistocene and which are related to the Rhône glacier. The latter brought about modifications in the base level by supplying its merging waters as well as moraine material. These variations in the base level shaped the drainage structure. The underground glacial polishes are one of the noteworthy aspects recorded.

The massives of the Moucherotte and dent de Crolles belong to the northern French Prealps. They conceal large networks, respectively the Vallier cave and the Dent de Crolles. They were formed in the early Pliocene after the final orogenic phase and are in the form of horizontal conduits. The upthrust, which brought about the embanking of the Isère valley, left them in a perched position by taking away the basin which fed them. They were later, however, able to take advantage of waters from the Isère glacier during a part of the Pleistocene. The Vallier cave contains particularly glacio-karstic sediments of the lower Pleistocene, representing unique evidence of glaciation during this period. The vertical networks were put in place at the end of the Pliocene with the increase in karstification potential ; they underwent changes in the Pleistocene due to the effect of autochton and allogenous glaciers.

The second part of the work deals in general with the various forms and processes of karstification, sometimes going beyond the Alps. The study of cave deposits is a privileged tool in the understanding and reconstruction not only of the history of the networks but also the regional environment. The dating of speleothems by the U / Th method has very ofen given an age of over 350 000 years. The age of the networks is confirmed by the use of paleomagnetism which has yielded evidence of speleothems and glacio-karstic sediments anterior to 780 000 years. Anisotropic measurements of magnetic susceptibility have been used to distinguish the putting into place of glacio-karstic deposits by decantation.

Measurements of calcite rates lead to a typology of sediments based on their nature and carbonate content (rehandled weathered rocks, fluvial sands, carbonated varves, decantation clays). Granulometry confirms this differenciation by supplying precise details of transport and sedimentation modes : suspension and abrupt precipitation of clay, suspension and slow decantation of carbonated varves, suspension and rolling together with a variable sorting of sand and gravel. Mineralogical analyses oppose two types of detrital deposits. On the one hand, the rehandling of antequaternary weathered rocks extracted by the karst as a result of scouring during environmental destabilization and on the other hand, sediments characteristic of the ice age of the Pleistocene. The latter are not highly developed and their arrival in the karst is always later. Examination of heavy minerals, the morphoscopy of quartz grains and study of micromorphologies on thin blades provide precise details of conditions of evolution. The use of these methods of investigation allows for an accurate definition of the features of the evolution of the differents types of fillings, particularly speleothems, rehandled weathered rocks as well as carbonated varves. This wealth and complexity are emphasized by a detailed study of the sedimentary sequences of the Vallier cave and of the Bergerhöhle.
Speleogenesis is approached last of all in the light of above study. Emphasis is placed on the major part played by corrosion in the temporarily phreatic zone and on its many consequences (multi-level concept, simultaneous evolution of levels, origin of deep waterlogged karsts…).
Varia tions in the base level have induced karstification in contexts in which the potential was weak. These were followed by periods of increased potential to which were added the effects of glaciation. Perched horizontal levels belong to the first stages which ended in the early Pliocene, whereas alpine shafts developed in the second context. The role of structure and the parameters governing the shape of conduits (pits, meanders, canyons) are also dealt with. The different parts of the karst are borne in mind when dealing with the strength of karstic erosion during the ice age. It notably appears that it is weak on the crests and more or less non-existent in the deep parts of the karst which are liable to flooding. Finally, a preliminary analysis of an observation of neotectonic traces is presented.


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.

Statistical evaluation of glacier boreholes as indicators of basal drainage systems, 1996, Smart C. C. ,
Between 1988 and 1992 closely spaced arrays of boreholes were drilled at Small River Glacier, British Columbia. The borehole arrays have been used to investigate the interannual and spatial consistency of patterns of basal hydraulics beneath the glacier. A simple robust classification was devised identifying unconnected, high standing, low standing and dry base water levels in boreholes. Spatial and interannual comparisons were made using a simple nearest neighbour statistic, corrected for differences in frequency of different borehole types and evaluated using Monte Carlo confidence intervals to compensate for array form. Arrays in the lower ablation zone showed spatial and interannual coherence, with three distinct areas characterized by low water pressure, till-associated non-connection and high pressure. There was no indication of a dominant conduit. Slightly higher up-glacier borehole patterns were less coherent, and varied from year to year, probably a result of subglacial karst capturing basal waters at a number of low pressure points at the bed. Therefore both the upper and lower arrays at Small River Glacier appear to encompass unusual drainage conditions. The nearest neighbour analysis provides valuable constraints on more specific interpretation

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