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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 land subsidence is the subsidence of a surface due to a loss of support [16]. often occurs as a result of over pumping underlying aquifers or as a result of mining activities. in karst terranes, subsidence can occur as a result of manmade changes to the natural hydrologic system (ground-water withdrawals or storm-water injection) or as a consequence of the natural dissolution process. subsidences may be sudden or progress slowly over time.?

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 glaciation (Keyword) returned 113 results for the whole karstbase:
Showing 16 to 30 of 113
Apports des datations U/Th dans la karstogense de la Grande Moucherolle-Rochers de la Balme (Vercors), 1986,
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Delannoy J. J. , Holliger Ph.
234 U - 230 Th DATING OF SPELEOTHEMS AND KARSTOGENESIS OF THE "GRANDE MOUCHEROLLE-ROCHERS DE LA BALME" (VERCORS) - In this article, is presented a first geomorphological and speleological synthesis of the subalpine karst of the Grande Moucherolle (2285 m) - Rochers de Ia Balme. This area of Vercors (Alps), which has 8 caves deeper than 300m (Antre des Damns -720m; Clos de La Fure -580m...) is surely the most promising sector from a speleological point of view. Through the study of the glacio-karstic landforms and the distri-bution of the great caves, it seems that there is a real relation between these two parameters. In order to evaluate the contribution of quaternary glaciations in the genesis of caves, isotopic dating (234U-230Th) have been performed on underground carbonated deposits. After a presentation of the chronometric method 234U-230Th, the results are analysed according to their speleological environment. A paleogeographic reconstitution through the middle and recent Quaternary is proposed for the geosystem of the Grande Moucherolle - Rochers de la Balme.

Le peuplement animal des karsts de France (lments de biogographie souterraine pour les invertbrs, premire partie : la faune aquatique), 1987,
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Ginet R. , Juberthie C.
THE BIOGEOGRAPHICAL DISTRIBUTION OF INVERTEBRATE ANIMALS IN FRENCH KARSTS (FIRST PART: THE AQUATIC FAUNA) - This text analyses the bibliographic data in order to draw up a schematic representation of the biogeographical distribution of Invertebrate animals found in French karsts up to 1985. The animal population of these karsts is very varied, especially in the South of France. For many groups, there are obvious links with geological history and paleo-ecology. This text first lists the aquatic groups (from Porifera to Crustacea; the latter is the most varied and numerous in karstic water). It puts forward possible solutions to the problems posed by the ways followed by the ancestors of present-day groups, either of superficial fresh-water origin, or of marine origin during the Tertiary, and whose areas were later modified by the impact of Quaternary glaciations. For the terrestrial groups (cf. Karstologia n 11), subterranean penetration followed different pathways, among which the Superficial Hypogean Compartment (MSS = Milieu Souterrain Superficiel) plays an obvious role; this shows that many troglobites are not limited, in the underground environment, to just caves and the karst. The Arthropods, and among them the Insects, are of course the most varied and the best known. Their biogeographical distribution reflects the problems of speciation, ecology and endemism, which are discussed in the text.

Observations prliminaires sur les cavits de la rgion du lac Centrum (NE Groenland), 1987,
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Loubiere, J. F.
CAVES OF CENTRUM LAKE AREA (NE GREELAND) - In 1983, M.Chiron, G.Favre, J-F. Loubire and J-P. Ttard identified a network of caves located in the extreme nord-east of Greenland. A cambro-silurian limestone zone stretches out to the south-west of Kronprins Christians land, the northern extremity of the great range of folded mountains of eastern Greenland. During an era characterised by the absence of permafrost and by a warmer climate favouring underground water circulation, these limestone formations were hollowed out by karstic river system. Such climatic conditions have long ceased to exist. During the major glaciations of the Quaternary period, the cavities were greatly modified. Glacier movements, cutting into the plateau, broke up the networks. The original underground deposits were then altered by allochtonous material of aeolian and morainic composition. Severe and ongoing frost shattering has added to this destructive process. It is hoped that this article will help to draw attention to these caves and to the more general subject of paleo-climates, especially their effects in the polar region during the Plio-Pleistocene transition (Electron Spin Resonance method on stalagmite and discovery of a mycelian hypha into calcite structure).

Le peuplement animal des karsts de France (deuxime partie : lments de biogographie pour les Invertbrs terrestres), 1988,
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Ginet R. , Juberthie C.
THE BIOGEOGRAPHICAL DISTRIBUTION OF INVERTEBRATE ANIMALS IN FRENCH KARSTS. SECOND PART THE TERRESTRIAL FAUNA - This text analyses the bibliographic data in order to draw up a schematic representation of the biogeographical distribution of Invertebrate animals found in french karsts up to 1985. The animal population of these karsts is very varied, especially in the south of France. For many groups, there are obvious links with geological history and paleo-ecology. This text first (cf. Karstologia n 10) lists the aquatic groups (from Porifera to Crustacea; the latter is the most varied and numerous in karstic water). It puts forward possible solutions to the problems posed by the ways followed by the ancestors of present-day groups, either of superficial freshwater origin, or of marine origin during the Tertiary, and whose areas were later modified by the impact of quaternary glaciations. This second part concerns the terrestrial groups, subterranean penetration followed different pathways, among which the Superficial Hypogean Compartment (MSS = Milieu Souterrain Superficiel) plays an obvious role; this shows that many troglobites are not limited in the underground environment, just to caves and karst. The Arthropods, and among them the Insects, are of course the most varied and the best known. Their bio-geographical distribution reflects the problems of speciation, ecology and endemism, which are discussed in the text.

Paleoenvironment and speciation in the cave beetle complex Speonomus delarouzeei (Coleoptera, Bathysciinae), 1988,
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Juberthie Christian
In the eastern part of the Pyrenees (France) the author describes a scenario of speciation in the cave species complex Speonomus delarouzeei (Coleoptera Bathysciinae); the speciation processes have been initiated by a breakdown of the ecological equilibrium induced during three glacial-interglacial episodes. The scenario is the following: during the first glaciation (2.3-2.1 MY), psychrophilic populations ancestral to S. brucki were selected over the highest elevation of the range, by means of cold effect which produced an adaptive demographic advantage; adaptive characters of troglobitic species (K strategy) take place presumably in relation to colonization of caves and M.S.S.; during the second glaciation (1.7-1.3 MY) and a more recent, S. charlottae, latter S. emiliae, diverged from troglobite ancestors of S. brucki without further adaptive characters, as result from stochastic and historical events. M.S.S. generated during erosional period of glacial event provided ways for migration and new niches for colonization. Bottleneck effect in size population of ancestors, founder effect, and colonization by local population which present genetic and behavioural geographical polymorphism, argue for a rapid speciation, presumably 100,000 years long and 50,000 generations in the case of S. emiliae.

Drainage Evolution in a Tasmanian Glaciokarst, 1989,
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Kiernan, Kevin

The intensively glaciated mountains of the Picton Range - Mt. Bobs area in southwestern Tasmania contain prominent karst features that have been developed in carbonate formations of Devonian, Ordovician and possibly Precambrian age. This paper reviews the extent of the karst and glacial features and records the tracing of the underground drainage from the alpine Lake Sydney. Glacial erosion has exposed areas of limestone to karstification and glacial diversion of drainage has played a critical role in the evolution of the present underground drainage patterns. Prior to the late Last Glacial Stage the deflection of marginal meltwaters from the former Farmhouse Creek Glacier against the Burgess - Bobs Saddle led to the development of an underground breach of a major surface drainage divide. Subglacial or submarginal meltwaters associated with a much smaller glacier that developed in the same valley during the late Last Glacial Stage probably played a significant role in the breaching of a minor divide within the Farmhouse Creek catchment. This led to the development of an underground anabranch of Farmhouse Creek that by-passes the glacial Pine Lake. However, it is possible that the latter diversion is entirely Holocene in age and is related to postglacial dilation of the limestone rather than meltwater flows.


Le massif de la Chartreuse, Alpes franaises du Nord : paysages karstiques et organisation des rseaux souterrains, 1990,
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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.

Glaciation and saline-freshwater mixing as a possible cause of cave formation in the eastern Midcontinent region of the United States; a conceptual model, 1990,
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Panno Samuel V. , Bourcier William L. ,

Karst features of a glaciated dolomite peninsula, Door County, Wisconsin, 1990,
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Johnson Scot B. , Stieglitz Ronald D. ,
A geologic investigation of the northern part of Door Peninsula, Wisconsin for a state funded water quality project revealed that karstification of the Silurian aquifer is more extensive than previously believed. Sinkholes and small insurgent features, solution modified crevices, pavements, caves and springs were inventories and mapped. These features are generally smaller and less densely developed than those in most limestone terranes; however, they are important to the geomorphology and water quality of the peninsula.Continental glaciation has strongly influenced both the distribution and the present surface morphology of the karst features. Ice scour has formed a stepped bedrock topography, contributed to pavement formation and may have removed some preglacial features. Deposition has plugged and masked features in places. In addition, subglacial water circulation, and ice loading and unloading may have influenced karst development

Karstification et volution palogographique du Jura, 1991,
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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.

The Mount Cripps karst, North Western Tasmania, 1991,
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Shannon Henry, Dutton Bevis, Heap David, Salt Frank

An Ordovician limestone karst area of 20 sqkm is presented. Characteristics: a large scale closed depression; a high density of caves formed by autogenic percolation with limited surface drainage; a polygonal karst terrain. The evolution of this karst was subject to multiple Pleistocene glaciations. At present 3 cave systems over 0,5 km in length are known, the deepest cave is -80 m.


Reactivated interstratal karst--example from the Late Silurian rocks of western Lake Erie (U.S.A.), 1992,
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Carlson Eh,
Interstratal karst developed in the Late Silurian rocks of western Lake Erie that, after a long interruption, was exhumed and reactivated. The dissolution front of the G evaporite of the Salina Group receded in the downdip direction during these two well-documented periods of subaerial exposure. The karst features that developed in the overlying Bass Islands Dolomite (Pridolian) consist of a large tabular body of collapse breccia and a number of smaller features including breccia pipes, partially filled pipes, blister caves and collapse dolines.The tabular breccia body and the breccia pipes, which originated penecontemporaneously during post-Silurian and pre-Middle Devonian subaerial exposure, occur along the updip edge of the present outcrop belt of the dolostone. They are monolithologic, fragment-supported rubble breccias, with the pipes exhibiting a greater fragment displacement, rotation and rounding, and a smaller fragment size. The matrix sediment of the tabular body is a quartz sand, an equivalent of the basal sandstone that filtered down from the erosion surface. The presence in the matrix sediment of nodular celestite, a later replacement of evaporites that formed when the sediment was still soft, indicates that a sabkha environment existed at the time the breccia was infilled. The partially filled pipes, which form cylindrical caves that are lined with late diagenetic celestite, are believed to be cogenetic with the collapse breccias.The blister caves and dolines occur downdip from the breccias, postdating Pleistocene glaciation and predating isostatic rebound. These caves are isolated, crescent- or oval-shaped openings with domed roofs, averaging about 60 m in width and 4 m in height. The hydration and resulting expansion of lenticular bodies of anhydrite along the receding solution front of the G unit is believed to be the cause of doming. The numerous crescentic caves, originating from the dissolution of this gypsum and the subsequent collapse of the domed roofs, are expressed at the surface as shallow dolines

REACTIVATED INTERSTRIATAL KARST EXAMPLE FROM THE LATE SILURIAN ROCKS OF WESTERN LAKE ERIE (USA), 1992,
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Carlson Eh,
Interstratal karst developed in the Late Silurian rocks of western Lake Erie that, after a long interruption, was exhumed and reactivated. The dissolution front of the G evaporite of the Salina Group receded in the downdip direction during these two well-documented periods of subaerial exposure. The karst features that developed in the overlying Bass Islands Dolomite (Pridolian) consist of a large tabular body of collapse breccia and a number of smaller features including breccia pipes, partially filled pipes, blister caves and collapse dolines. The tabular breccia body and the breccia pipes, which originated penecontemporaneously during post-Silurian and pre-Middle Devonian subaerial exposure, occur along the updip edge of the present outcrop belt of the dolostone. They are monolithologic, fragment-supported rubble breccias, with the pipes exhibiting a greater fragment displacement, rotation and rounding, and a smaller fragment size. The matrix sediment of the tabular body is a quartz sand, an equivalent of the basal sandstone that filtered down from the erosion surface. The presence in the matrix sediment of nodular celestite, a later replacement of evaporites that formed when the sediment was still soft, indicates that a sabkha environment existed at the time the breccia was infilled. The partially filled pipes, which form cylindrical caves that are lined with late diagenetic celestite, are believed to be cogenetic with the collapse breccias. The blister caves and dolines occur downdip from the breccias, postdating Pleistocene glaciation and predating isostatic rebound. These caves are isolated, crescent- or oval-shaped openings with domed roofs, averaging about 60 m in width and 4 m in height. The hydration and resulting expansion of lenticular bodies of anhydrite along the receding solution front of the G unit is believed to be the cause of doming. The numerous crescentic caves, originating from the dissolution of this gypsum and the subsequent collapse of the domed roofs, are expressed at the surface as shallow dolines

STABLE ISOTOPIC COMPOSITION OF METEORIC CALCITES - EVIDENCE FOR EARLY MISSISSIPPIAN CLIMATE-CHANGE IN THE MISSION CANYON FORMATION, MONTANA, 1993,
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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,
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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.


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