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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 rational formula is an equation relating runoff intensity and area to a runoff coefficient [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 melting (Keyword) returned 46 results for the whole karstbase:
Showing 16 to 30 of 46
Sheet flow caves of Kilauea Caldera, Hawaii County, Hawaii., 1998, Halliday William R.
Terminal lobes of sheet flows of pahoehoe lava sometimes form three-dimensional nests, initially separated by partitions consisting of accreted 'skins" of each lobe. Melting breaks down these partitions, forming a uniform flow unit. In Kilauea Caldera we have found and mapped sizable drained cavities in low-slope sheet flows. Their general pattern includes three-dimensional nests, with partially melted septa evident in some examples. Christmas Cave is the most extensive found to date, with 632 meters surveyed on two levels. It is located at the lower end of an inflated sheet flow tongue which underwent local deflation as a result of drainage through the cave after its parameters were partially fixed. Small conduit remnants persist in its boundary ridges. The major part of the cave consists of wide, low nestled chambers. Meltdown of such partitions is one of the few emplacement mechanisms of thermal erosion which may not involve any mechanical element. Additional caves in this caldera are being identified and studied.

Quelques aspects des conditions de circulation des eaux souterraines dans les karsts du gypse des Alpes internes, 1999, Couturier Bernard, Fourneaux Jeanclaude, Sommeria Laure
The Triassic gypsum outcrops are widespread, in the French Inner Alps. They are often found in large heaps between two structural units. Karstic landforms with sinkholes and collapse zones are visible even when they are covered with glacial deposits or fallen rocks. There is also much evidence of underground flows, but the springs do not have any karstic characteristics. The water tracings (two examples) show that the local tectonics have a great influence in the subterranean circulation conditions. At "La Norma" in the Arc valley (Maurienne) the water infiltrated in a large sinkhole supplies several small springs after transit in a fissured aquifer. The spring flow is well regulated. At "Le Clou" in the upper Isre valley (Tarentaise) several sinkholes with loss of ephemeral streams during melting snow supply a large fissured aquifer. There is no spring with karstic features either. The water infiltrated in a sinkhole has been found in several springs during a very long period of time. Whereas the upper part of these aquifers are really like a karstic aquifer, with large stream channels, on the contrary the deeper part is like a fissured aquifer with large water dispersion and low velocity. The fissured and porous aquifer has a throttling action and explains the absence of true resurgence. The underground water flow is unbroken between the different aquifers but permeability decreases according to the depth. These phenomenon are in connection with tectonic activity and the interpenetration of the different geological formations at the bottom of the gypsum layer.

Les glaciers de marbre de Patagonie, Chili : un karst subpolaire ocanique de la zone australe, 1999, Maire Richard, Ultima_esperanza_team
The karst areas of Chilean Patagonia have remained virtually unknown until now because of their remoteness and very inhospitable climate. They are mainly located in two islands, Diego de Almagro and Madre de Dios, between latitude 52 and 50 South, with a subpolar and stormy climate "tempered" by heavy oceanic precipitations (7 m/ year). In Diego de Almagro the Permian and Carboniferous limestones and dolomites have been transformed into marbles with lamprophyre dikes through contact metamorphism. Situated in the outer part of the archipelagoes, these long and narrow outcrops (0.5-2km wide) are located between volcano-sedimentary formations of Upper Paleozoic (West) and the Mesozoic Patagonian batholit (East). The corallian paleoreefs are part of an accretionary prism of the Gondwana paleo-continent. The surficial and underground karstification is one of the most spectacular ones in the world. The Karren (lapies) caused by the heavy rains can be 1-4 meter(s) wide and several hundred meters long for the solution runnels. Moreover, we can often observe solution karrens both due to rain and wind direction: flat karren (horizontal laminar flow), cascading ripples (sloping laminar flow) and profiled solution forms. The surficial solution velocity is about 3 mm/50 years (from old painting traces near the quarry of Guarello, Madre de Dios); and the lamprophyres dikes (Diego de Almagro) put in relief through corrosion indicate a 40-60 cm surficial solution since the melting of pleistocene glaciers.

Vein and Karst Barite Deposits in the Western Jebilet of Morocco: Fluid Inclusion and Isotope (S, O, Sr) Evidence for Regional Fluid Mixing Related to Central Atlantic Rifting, 2000, Valenza Katia, Moritz Robert, Mouttaqi Abdellah, Fontignie Denis, Sharp Zachary,
Numerous vein and karst barite deposits are hosted by Hercynian basement and Triassic rocks of the western Jebilet in Morocco. Sulfur, oxygen, and strontium isotope analyses of barite, combined with fluid inclusion microthermometry on barite, quartz, and calcite were used to reveal the nature and source of the ore-forming fluids and constrain the age of mineralization. The{delta} 34S values of barite between 8.9 and 14.7 per mil are intermediate between the sulfur isotope signatures of Triassic evaporites and Triassic-Jurassic seawater and lighter [IMG]f1.gif' BORDER='0'>, probably derived from the oxidation of dissolved H2S and leaching of sulfides in the Hercynian basement. The 87Sr/86Sr ratios of barite between 0.7093 and 0.7130 range between the radiogenic strontium isotope compositions of micaceous shale and sandstone and the nonradiogenic isotopic signature of Triassic to Jurassic seawater and Cambrian limestone. The{delta} 18O values of barite between 11 and 15 per mil (SMOW) support mixing between two or more fluids, including Late Triassic to Jurassic seawater or a water dissolving Triassic evaporites along its flow path, hot basinal, or metamorphic fluids with{delta} 18O values higher than 0 per mil and/or meteoric fluids with{delta} 18O values lower than 0 per mil. The general trend of decreasing homogenization temperatures and initial ice melting temperatures with increasing salinities of H2O-NaCl {} CaCl2 fluid inclusions trapped in barite, quartz, and calcite indicates that a deep and hot basinal fluid with salinities lower than 6 wt percent NaCl equiv might have mixed with a cooler surficial solution with a mean salinity of 20 wt percent NaCl equiv. Calcium was leached from the Cambrian limestone and the clastic and mafic volcanic rocks of the Hercynian basement. Alkali feldspars and micas contained in the Cambrain sandstones provided most of the Ba to the hydrothermal system. Vein and karst deposits are modeled as a two-component mixing process in which the temperature and the S and Sr isotope composition of the end members changed during the 220 to 155 Ma interval. The hot basinal fluid remained volumetrically dominant during the entire mineralization process. Differences in mean S, O, and Sr isotope compositions among the barite families are interpreted as reflecting differences in mineralization age. Most barite deposits formed before the Kimmeridgian, except for north-south-oriented vein barite, karst barite, and barite cement in the conglomeratic Upper Jurassic, which were deposited later, possibly around 155 Ma. Similar genetic processes have been described for late Paleozoic to Mesozoic F-Ba vein deposits in western Europe. The vein and karst barite in the western Jebilet of Morocco reveals a wide-scale regional mineralization event related to Central Atlantic rifting

Geochemical study of calcite veins in the Silurian and Devonian of the Barrandian Basin (Czech Republic): evidence for widespread post-Variscan fluid flow in the central part of the Bohemian Massif, 2000, Suchy V. , Heijlen W. , Sykorova I. , Muchez Ph. , Dobes P. , Hladikova J. , Jackova I. , Safanda J. , Zeman A.

Carbonate fracture cements in limestones have been investigated by fluid inclusion and stable isotope analysis to provide insight into fluid evolution and deformation conditions of the Barrandian Basin (Silurian–Devonian) of the Czech Republic. The fractures strike generally north–south and appear to postdate major Variscan deformation. The most common fracture cement is calcite that is locally accompanied by quartz, natural bitumen, dolomite, Mn-oxides and fluorite. Three successive generations of fracture-filling calcite cements are distinguished based on their petrographical and geochemical characteristics. The oldest calcite cements (Stage 1) are moderate to dull brown cathodoluminescent, Fe-rich and exhibit intense cleavage, subgrain development and other features characteristic of tectonic deformation. Less tectonically deformed, variable luminescent Fe-poor calcite corresponds to a paragenetically younger Stage 2 cement. First melting temperatures, Te, of two-phase aqueous inclusions in Stages 1 and 2 calcites are often around 2208C, suggesting that precipitation of the cements occurred from H2O–NaCl fluids. The melting temperature, Tm, has values between 0 and 25.88C, corresponding to a low salinity between 0 and 8.9 eq. wt% NaCl. Homogenization temperatures, Th, from calcite cements are interpreted to indicate precipitation at about 708C or less. No distinction could be made between the calcite of Stages 1 and 2 based on their fluid inclusion characteristics. In some Stage 2 cements, inclusions of highly saline (up to 23 eq. wt% NaCl) brines appear to coexist with low-salinity inclusions. The low salinity fluid possibly contains Na-, K-, Mg- and Ca-chlorides. The high salinity fluid has a H2O–NaCl–CaCl2 composition. Blue-to-yellow-green fluorescing hydrocarbon inclusions composed of medium to higher API gravity oils are also identified in some Stages 1 and 2 calcite cements. Stage 1 and 2 calcites have d 18O values between 213.2‰ and 27.2‰ PDB. The lower range of the calculated d 18O values of the ambient fluids (23.5‰ to 1 2.7‰ SMOW) indicate precipitation of these cements from deeply circulating meteoric waters. The presence of petroleum hydrocarbon inclusions in some samples is interpreted to reflect partial mixing with deeper basinal fluids. The paragenetically youngest Stage 3 calcite cement has only been encountered in a fewveins.These calcites are characterised by an intensely zoned luminescence pattern, with bright yellow and non-luminescent zones. Inclusions of Mn-oxides and siliceous sinters are commonly associated with Stage 3 calcite, which is interpreted to have precipitated from shallower meteoric waters. Regional structural analysis revealed that the calcite veins of the Barrandian basin belong to a large-scale system of north–south-trending lineaments that run through the territory of the Czech Republic. The veins probably reflect episodes of fluid migration that occurred along these lineaments during late stages of the Variscan orogeny


Constraints on Black Sea outflow to the Sea of Marmara during the last glacial-interglacial transition, 2002, Major Candace, Ryan William, Lericolais Gilles, Hajdas Irka,
New cores from the upper continental slope off Romania in the western Black Sea provide a continuous, high-resolution record of sedimentation rates, clay mineralogy, calcium carbonate content, and stable isotopes of oxygen and carbon over the last 20[punctuation space]000 yr in the western Black Sea. These records all indicate major changes occurring at 15[punctuation space]000, 12[punctuation space]800, 8400, and 7100 yr before present. These results are interpreted to reflect an evolving balance between water supplied by melting glacial ice and other river runoff and water removed by evaporation and outflow. The marked retreat of the Fennoscandian and Alpine ice between 15[punctuation space]000 and 14[punctuation space]000 yr is recorded by an increase in clays indicative of northern provenance in Black Sea sediments. A short return toward glacial values in all the measured series occurs during the Younger Dryas cold period. The timing of the first marine inflow to the Black Sea is dependent on the sill depths of the Bosporus and Dardanelles channels. The depth of the latter is known to be -805 m, which is consistent with first evidence of marine inundation in the Sea of Marmara around 12[punctuation space]000 yr. The bedrock gorge of the Bosporus reaches depths in excess of -100 m (relative to present sea level), though it is now filled with sediments to depths as shallow as -32 m. Two scenarios are developed for the connection of the Black Sea with the Sea of Marmara. One is based on a deep Bosporus sill depth (effectively equivalent to the Dardanelles), and the other is based on a shallow Bosporus sill (less than -35 m). In the deep sill scenario the Black Sea's surface rises in tandem with the Sea of Marmara once the latter connected with the Aegean Sea, and Black Sea outflow remains continuous with inflowing marine water gradually displacing the freshwater in the deep basin. The increase in the [delta]18O of mollusk shells at 12[punctuation space]800 yr and the simultaneous appearance of inorganic calcite with low [delta]18O is compatible with such an early marine water influx causing periodic weak stratification of the water column. In the shallow sill scenario the Black Sea level is decoupled from world sea level and experiences rise and fall depending on the regional water budget until water from the rising Sea of Marmara breaches the shallow sill. In this case the oxygen isotope trend and the inorganic calcite precipitation is caused by increased evaporation in the basin, and the other changes in sediment properties reflect climate-driven river runoff variations within the Black Sea watershed. The presence of saline ponds on the Black Sea shelf circa 9600 yr support such evaporative draw-down, but a sensitive geochemical indicator of marine water, one that is not subject to temperature, salinity, or biological fractionation, is required to resolve whether the sill was deep or shallow

Melting of the glacier base during a small-volume subglacial rhyolite eruption: evidence from Blahnukur, Iceland, 2002, Tuffen H. , Pinkerton H. , Mcgarvie D. W. , Gilbert J. S. ,
Although observations of recent volcanic eruptions beneath Vatnajokull, Iceland have improved the understanding of ice deformation and meltwater drainage, little is known about the processes that Occur at the glacier base. We present observations of the products of a small-volume, effusive subglacial rhyolite eruption at Blahnukur. Torfajokull, Iceland. Lava bodies, typically 7 m long, have unusual conical morphologies and columnar joint orientations that suggest emplacement within cavities melted into the base of a glacier. Cavities appear to have been steep-walled and randomly distributed. These features can be explained by a simple model of conductive heat loss during the ascent of a lava body to the glacier base. The released heat melts a cavity in the overlying ice. The development of vapour-escape pipes in the waterlogged, permeable breccias surrounding the lava allows rapid heat transfer between lava and ice. The formed meltwater percolates into the breccias, recharging the cooling system and leaving a steam-filled cavity. The slow ascent rates of intrusive rhyolitic magma bodies provide ample time for a cavity to be melted in the ice above, even during the final 10 m of ascent to the glacier base. An equilibrium Cavity Size is Calculated at which melting, is balanced by creep closure, This is dependent upon the heat input and the difference between glaciostatic and cavity pressure. The cavity sizes inferred from Blahnukur are consistent with a pressure differential of 2-4 MPa, suggesting that the ice was at least 200 m thick. This is consistent with the volcanic stratigraphy, which indicates that the ice exceeded 350 in in thickness, Although this is the first time that a subglacial cavity system of this type has been reconstructed from an ancient volcanic sequence. it shares many characteristics with the modem fim cave system formed by fumarolic melting within the summit crater of Mount Rainier. Washington, At both localities, it appears that localised heating at the glacier base has resulted in heterogeneous melting patterns. Despite the different theological properties of ice and fim, similar patterns of cavity roof deformation are inferred. The development of low-pressure subglacial cavities in regions of high heat nux may influence the trajectory of rising magma, with manifold implications for eruptive mechanisms and resultant subglacial volcanic landforms. (C) 2002 Elsevier Science B.V. All rights reserved

Vitesse de recul dun escarpement lapiaz (Ile Diego de Almagro, Patagonie, Chili),, 2003, Veress Mrton, Toth Gbor, Zentai Zoltn, Czpek Istvn
Backward rate of a marble side slope (Island Diego de Almagro, Chilean Patagonia) - Our research group measured the dissolution caused regressive velocity of the marbles side slope on one of the marble stripes on the island of Diego de Almagro. Using the time of ice melting and the width of rim bordering the edge of the sidewall the velocity of regression is 0,4-0,5 mm per year. This velocity of regression exceeds with an order of magnitude the velocity of denudation caused by dissolution on marble surface. Due to this fact, the marble stripes of the island become narrower to a bigger degree than they become shorter.

Nonsulfide Zinc Mineralization in Europe: An Overview, 2003, Boni M, Large D,
A number of occurrences and deposits of nonsulfide zinc ores in Europe were the historical basis for the development of the zinc mining and smelting industry. The principal occurrences in Silesia (Poland), Sardinia (Italy), and northern Spain are described. These deposits are products of the supergene oxidation of primary carbonate-hosted sulfide minerals during the complex interplay of tectonic uplift, karst development, changes in the level of the water table, and weathering. The nonsulfide zinc mineral deposits in the Irish Midlands may represent an example of surface oxidation of primary sulfide mineral deposits, redeposition, and preservation under glacial till. The willemite-dominated mineralization at La Calamine, Belgium, may be related to paleoweathering or be of possible hydrothermal origin, similar to other willemite deposits in the world

Fens in karst sinkholes - Archives for long lasting 'immission' chronologies, 2003, Hettwer K. , Deicke M. , Ruppert H. ,
Fens in karst sinkholes are excellent archives for the reconstruction of vegetation, land use and emission rates over millennia. The reasons are the usually good preservation of pollen, the high portion of low density organic material with very low background concentrations of heavy metals, and the circum-neutral pH-values in most of these mires preventing migration of heavy metals. Immissions of dust and of harmful elements can easily be correlated with changes in vegetation ('immission' is a synonym for the deposition or impact of pollutants from the atmosphere on a receptor surface). One 13 m core from a similar to5000 yr old karst sinkhole fen (Silberhohl, western margin of the Harz Mountains, central Germany) was investigated by geochemical analysis, pollen analysis and dated by C-14 and palynological data. The core consists of organic material with a few percent of CaCO3 precipitated from groundwater and a small amount of atmospheric detritus. As early as the Iron Age (first pre-Christian millennium), slight but significant enrichments of Pb, Zn, Cu and Cd are observed. After 400 AD stronger enrichments occurred culminating in the High Middle Ages (similar to1200-1300 AD). Maximum values are 1250 mug g(-1) Pb, 214 mug g(-1) Cu, 740 mug g(-1) Zn, and 3.8 mug g(-1) Cd. The enrichments are caused by emissions during smelting of sulfidic lead-zinc ores from the adjacent Hercynian deposits to extract Ag and Cu. Except for cadmium, these values were never exceeded in modern times. Since the Iron Age 23 g technogenic Pb, 5.3 g Cu, 27 g Zn and 0.2 g Cd have been deposited per square meter. Palynological investigations show a strong correlation between decreasing red beech pollens (Fagus sylvatica) and increasing demand on wood for smelting in the Middle Ages. Simultaneously, the pollen share of pioneer trees such as birch (Betula pubescens) and of cereal grains (e.g. Secale) increases. Since the beginning of the 14th century, the decline of agriculture and population is reflected in the decreasing contents of Secale and heavy metals in the fen deposits

Kitzsteinhorn high alpine karst (Salzburg, Austria): Evidence of non-glacial speleogenesis., 2004, Audra, Ph.
Cave and karst development in a recently deglaciated alpine area (Kitzsteinhorn, Salzburg, Austria) is examined and compared to presently and previously glaciated karst regions elsewhere. Field evidence suggests that cave genesis occurs mainly during warm, interglacial periods when vegetation and soil formation provide chemically aggressive runoff during the melting season. During periods of extensive glacier coverage, the glacial contribution to karst development is restricted to surface abrasion, shaft development in pre-existing vadose caves and infill of fine-grained sediment in the epiphreatic zone. [Feichtner-Schachthhle (2573/3)]

Kitzsteinhorn high alpine karst (Salzburg, Austria): Evidence of non-glacial speleogenesis, 2004, Audra, Ph.
Cave and karst development in a recently deglaciated alpine area (Kitzsteinhorn, Salzburg, Austria) is examined and compared to presently and previously glaciated karst regions elsewhere. Field evidence suggests that cave genesis occurs mainly during warm, interglacial periods when vegetation and soil formation provide chemically aggressive runoff during the melting season. During periods of extensive glacier coverage, the glacial contribution to karst development is restricted to surface abrasion, shaft development in pre-existing vadose caves and infill of fine-grained sediment in the epiphreatic zone.

Solution-collapse breccias of the Minkinqellet and Wordiekammen Formations, Central Spitsbergen, Svalbard: a large gypsum palaeokarst system, 2005, Eliassen A, Talbot Mr,
Large volumes of carbonate breccia occur in the late syn-rift and early post-rift deposits of the Billefjorden Trough, Central Spitsbergen. Breccias are developed throughout the Moscovian Minkinfjellet Formation and in basal parts of the Kazimovian Wordiekammen Formation. Breccias can be divided into two categories: (i) thick, cross-cutting breccia-bodies up to 200 m. thick that are associated with breccia pipes and large V-structures, and (ii) horizontal stratabound breccia beds interbedded with undeformed carbonate and siliciclastic rocks. The thick breccias occur in the central part of the basin, whereas the stratabound breccia beds have a much wider areal extent towards the basin margins. The breccias were formed by gravitational collapse into cavities formed by dissolution of gypsum and anhydrite beds in the Minkinfjellet Formation. Several dissolution fronts have been discovered, demonstrating the genetic relationship between dissolution of gypsum and brecciation. Textures and structures typical of collapse breccias such as inverse grading, a sharp flat base, breccia pipes (collapse dolines) and V-structures (cave roof collapse) are also observed. The breccias are cemented by calcite cements of pre-compaction, shallow burial origin. Primary fluid inclusions in the calcite are dominantly single phase containing fresh water (final melting points are ca 0 degrees C), suggesting that breccia diagenesis occurred in meteoric waters. Cathodoluminescence (CL) zoning of the cements shows a consistent pattern of three cement stages, but the abundance of each stage varies stratigraphically and laterally. delta(18)O values of breccia cements are more negative relative to marine limestones and meteoric cements developed in unbrecciated Minkinfjellet limestones. There is a clear relationship between delta(18)O values and the abundance of the different cement generations detected by CL. Paragenetically, later cements have lower delta(18)O values recording increased temperatures during their precipitation. Carbon isotope values of the cements are primarily rock-buffered although a weak trend towards more negative values with increasing burial depth is observed. The timing of gypsum dissolution and brecciation was most likely related to major intervals of exposure of the carbonate platform during Gzhelian and/or Asselian/Sakmarian times. These intervals of exposure occurred shortly after deposition of the brecciated units and before deep burial of the sediments

Solution-collapse breccias of the Minkinfjellet and Wordiekammen Formations, Central Spitsbergen, Svalbard; a large gypsum palaeokarst system. , 2005, Eliassen Arild, Talbot Michael R.

Large volumes of carbonate breccia occur in the late syn-rift and early post-rift deposits of the Billefjorden Trough, Central Spitsbergen. Breccias are developed throughout the Moscovian Minkinfjellet Formation and in basal parts of the Kazimovian Wordiekammen Formation. Breccias can be divided into two categories: (i) thick, cross-cutting breccia-bodies up to 200 m thick that are associated with breccia pipes and large V-structures, and (ii) horizontal stratabound breccia beds interbedded with undeformed carbonate and siliciclastic rocks. The thick breccias occur in the central part of the basin, whereas the stratabound breccia beds have a much wider areal extent towards the basin margins. The breccias were formed by gravitational collapse into cavities formed by dissolution of gypsum and anhydrite beds in the Minkinfjellet Formation. Several dissolution fronts have been discovered, demonstrating the genetic relationship between dissolution of gypsum and brecciation. Textures and structures typical of collapse breccias such as inverse grading, a sharp flat base, breccia pipes (collapse dolines) and V-structures (cave roof collapse) are also observed. The breccias are cemented by calcite cements of pre-compaction, shallow burial origin. Primary fluid inclusions in the calcite are dominantly single phase containing fresh water (final melting points are ca 0 degrees C), suggesting that breccia diagenesis occurred in meteoric waters. Cathodoluminescence (CL) zoning of the cements shows a consistent pattern of three cement stages, but the abundance of each stage varies stratigraphically and laterally. delta (super 18) O values of breccia cements are more negative relative to marine limestones and meteoric cements developed in unbrecciated Minkinfjellet limestones. There is a clear relationship between delta (super 18) O values and the abundance of the different cement generations detected by CL. Paragenetically, later cements have lower delta (super 18) O values recording increased temperatures during their precipitation. Carbon isotope values of the cements are primarily rock-buffered although a weak trend towards more negative values with increasing burial depth is observed. The timing of gypsum dissolution and brecciation was most likely related to major intervals of exposure of the carbonate platform during Gzhelian and/or Asselian/Sakmarian times. These intervals of exposure occurred shortly after deposition of the brecciated units and before deep burial of the sediments.
 


Grottes et karsts dEurope centrale dans les Encyclopdies franaises du XVIIIe sicle, 2006, Gauchon Christophe
Central European caves and karsts in French Encyclopaedias of xviiith century - The xviiith century, and especially the second half, was a time of great progress in natural history and, more particularly, in the knowledge of caves, and this interest for caves appeared in several Encyclopaedias published in that time. At the very end of xviith century, several dictionaries of History or Geography [Baudrand, Moreri] were printed in France. Their aim was to give a wide panorama of the whole human knowledge. After 1750, D. Diderot and J. dAlembert began the publishing of the great Encyclopaedia, or reasoned dictionary of sciences, arts and technology [1751-1765]. More than just a dictionary, this major opus of the Enlightenments purposed to criticize all the old knowledges, with the intention of rebuilding by the reason a new understanding of the world. As it was considered disrespectful towards church, Jesuits published another Encyclopaedia, the Dictionnaire de Trvoux . Then, at the end of xviiith century, Panckoucke published the huge Methodical Encyclopaedia , with three volumes for modern Geography and five for physical Geography . So, dozens and dozens of caves all over the world were described in these dictionaries and Encyclopaedias, and here well try to expose what is about central Europe. The articles about regional geography (Istria, Alps) were often reduced to historical relations or to very poor lists of geographical names. Before the publishing of the last Encyclopaedia of the century, travellers relations seemed unknown by the authors of the dictionaries. The methodical Encyclopaedia showed a clear progress with, for instance, two articles about Croatia: the article river Cettina described several phenomena of karstic hydrology; or the article Biocova dealt with the ice-caves of the Mont-Mossor. It seems that Dictionaries and encyclopaedias had better information about caves of France or Germany where fossilized bones had been discovered. Some caves of the Mediterranean countries were also well known, because of the mythological or biblical traditions; numerous references to Timavo spring were based only on ancient roman geographers. But what about the caves of central Europe? The cave of Retelstein in Styria and the cave of Ribar (Hungary) were described in the great Encyclopaedia, and the article Cave gave a long list in which we find a short mention of the caves of Postojna and Podpec (Slovenia). But the longest articles were about Cirknitz Lake: all the dictionaries gave a large place to this famous place for hunting, fishing and ploughing , as repeated Moreri or Baudrand who looked at this phenomenon as a wonder. In the great Encyclopaedia, the description was much more accurate and tried to explain the working of the lake in the surroundings: the sink holes and the resurgences were well identified. These accurate descriptions of Cirknitz Lake stand in strong contrast with the short mentions of Postojna, which is still supposed to be two milles long As to Recca of San Canzian, this place never appeared in French dictionaries and Encyclopaedias of the xviiith century: Skocjan seemed completely unknown But these various spots were described without any connection among them. If the authors of the Encyclopaedias wanted to break definitively with all the superstitions from old ages, they were not yet able to understand the meaning of what we call karstic landscapes . On this point, the age of Enlightenments appears as a time of transition. Now, articles about Carniole (former name for main part of Slovenia) show an interesting evolution of the authors points of view. Masson de Morvilliers in the Methodical Encyclopaedia (modern Geography) explained that this country contains many noteworthy caves . And in the volume v of physical Geography [1828], the article about Zirknitz Lake ended with this interesting remark: The whole range of surrounding mountains is composed with porous limestone in which rain and snow-melting waters enter () The whole country, from north borders of Carniola to the shores of Adriatic Sea, and from the caves of Planina to the Timavo Springs, is full with streams suddenly issued from the ground and pointing out a subterranean current, which is logically to link with the working of Zirknitz Lake. So, with the help of these Encyclopaedias, we may have a good survey of the erudite geography of Karst in xviiith century and we can understand the basis on which the knowledge would get positive progress during the xixth one.

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