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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 uniaxial (unconfined) compression is compression caused by the application of normal stress in a single direction.?

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Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
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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 tethys (Keyword) returned 13 results for the whole karstbase:
Bogidiella martini, a new hypogean Amphipod from the island of Saint-Martin (West Indies) and the zoogeography of the Bogidiellidae., 1978, Stock Jan H.
Both sexes of a new species of Bogidiella, B. martini, are described. The new species, with a very pronounced sexual dimorphism, has been discovered in two wells in the island of St.-Martin (French part), one of the Lesser Antilles. Another member of Bogidiella has been recorded from the island of Curaao, but the specimens were damaged too much to allow proper description. The Bogidiellidae (5 genera, 26 named species, and several unnamed species) are present in the sea as well as in inland waters. The family has a wide distribution, exceeding the boundaries of the former Tethys Sea. Probably, they represent a very old stock that had acquired already a great part of its present-day distribution before the fragmentation of the primordial continent of Pangaea during the Mesozoic.

Les palokarsts des Alpes occidentales du Trias l'Eocne, 1984, Guendon, J. L.
WESTERN ALPS PALEOKARSTS FROM TRIASSIC TO EOCENE - In western Alps, before complete emersion during the Oligocene and Miocene, the marine sedimentation has been locally interrupted by three important continental phases: 1/ during Early Jurassic, in "brianonnais" domain; 2/during middle Cretaceous, in Provence area; 3/ during early Tertiary, in subalpine range and Jura. These locally and temporary regression are the consequence of tectonic activities in relation to the movements of eurasiatic and italo-african plates, which are at the edge of the alpine oceanic basin (Tethys). After an abstract on the tectonic and sedimentological history of western Alps, a description is given of continental formations (bauxites, fire-clay, clay with flints, siderolitic formations, white and ochrous sands, siliceous and ferruginous crusts) and karst phenomena elaborated during these regressions.

Petroleum geology of the Black Sea, 1996, Robinson A. G. , Rudat J. H. , Banks C. J. , Wiles R. L. F. ,
The Black Sea comprises two extensional basins formed in a back-arc setting above the northward subducting Tethys Ocean, close to the southern margin of Eurasia. The two basins coalesced late in their post-rift phases in the Pliocene, forming the present single depocentre. The Western Black Sea was initiated in the Aptian, when a part of the Moesian Platform (now the Western Pontides of Turkey) began to rift and move away to the south-east. The Eastern Black Sea probably formed by separation of the Mid-Black Sea High from the Shatsky Ridge during the Palaeocene to Eocene. Subsequent to rifting, the basins were the sites of mainly deep water deposition; only during the Late Miocene was there a major sea-level fall, leading to the development of a relatively shallow lake. Most of the margins of the Black Sea have been extensively modified by Late Eocene to recent compression associated with closure of the Tethys Ocean. Gas chromatography--mass spectrometry and carbon isotope analysis of petroleum and rock extracts suggest that most petroleum occurrences around the Black Sea can be explained by generation from an oil-prone source rock of most probably Late Eocene age (although a wider age range is possible in the basin centres). Burial history modelling and source kitchen mapping indicate that this unit is currently generating both oil and gas in the post-rift basin. A Palaeozoic source rock may have generated gas condensate in the Gulf of Odessa. In Bulgarian waters, the main plays are associated with the development of an Eocene foreland basin (Kamchia Trough) and in extensional structures related to Western Black Sea rifting. The latter continue into the Romanian shelf where there is also potential in rollover anticlines due to gravity sliding of Neogene sediments. In the Gulf of Odessa gas condensate has been discovered in several compressional anticlines and there is potential in older extensional structures. Small gas and oil discoveries around the Sea of Azov point to further potential offshore around the Central Azov High. In offshore Russia and Georgia there are large culminations on the Shatsky Ridge, but these are mainly in deep water and may have poor reservoirs. There are small compressional structures off the northern Turkish coast related to the Pontide deformation; these may include Eocene turbidite reservoirs. The extensional fault blocks of the Andrusov Ridge (Mid-Black Sea High) are seen as having the best potential for large hydrocarbon volumes, but in 2200 m of water

Dinosaurs and other tetrapods in an Early Cretaceous bauxite-filled fissure, northwestern Romania, 1997, Benton Mj, Cook E, Grigorescu D, Popa E, Tallodi E,
The bauxite mine at Cornet near Oradea in northwestern Romania produced thousands of bones in an excavation in 1978, mainly from ornithopod dinosaurs and rarer pterosaurs. Bird specimens reported previously from this fauna are equivocal. The fossils are disarticulated bones in good condition which occur highly concentrated in lenses within bauxite clays, which are dated as Berriasian (earliest Cretaceous). The bauxite represents detrital material washed into deep fissures and caves formed within a karst of uplifted Tithonian (latest Jurassic) marine limestones. The bones are generally uniform in size and shape, and they are abraded, evidence for considerable transport and for winnowing of the deposit. The area was one of several islands on the northern shore of Tethys, and it was inundated by the sea later in the Early Cretaceous. There is evidence for insular adaptations in the dinosaur faunas. The ornithopod dinosaurs may include several taxa, but they are smaller on average than an assemblage of typical Wealden ornithopods, perhaps because of dwarfing on the island. In addition, sauropods are absent and theropods are barely represented in the fauna. The fauna is geographically significant since it shows relationships with western Europe and with Asia

Precipitation and alteration of late Cretaceous sedimentary apatites and siderites (Leonie Trough, Bavaria, Germany), 1998, Sattler C. D. , Halbach P. ,
Late Cretaceous sedimentary siderites and fluorapatites of the iron ore deposit 'Leonie' (Bavaria, Germany) have been investigated by geochemical and mineralogical methods to define their origin. The siderites consist to more than 90 mol% of FeCO3. This elemental composition relates to an early diagenetic fresh water depositional environment. The stable isotope geochemistry of carbon and oxygen (delta(18)O: parts per thousand SMOW; delta(13)C: -12 parts per thousand PDB) also supports a siderite genesis in meteoric waters, with carbon originating from oxidation of organic matter. The chemical composition of the fluorapatites is relatively pure and shows a very low elemental substitution for calcium and phosphate. This is the result of an intense epigenetic alteration of the primary carbonate fluorapatite and, thus, cannot be related to specific source aspects. Microscopic investigations and thermodynamic calculations reveal a precursory apatite precipitation before siderite was formed. This process is thought to have removed calcium from karst waters to a level which enables siderite to be precipitated. Because of the data and observations a siderite formation in a stagnant fresh water basin is postulated, while the apatite formation probably was initiated during a connection to the open ocean (Tethys) with temporary marine ingressions. The input of iron and partly of phosphorus and fluorine into the karst basins resulted from the draining of the uplifted easterly mountains of the igneous Bohemian Massif under the influence of a humid warm climate. During the postulated marine ingressions especially phosphorus and fluorine were brought into the system whereas most of the calcium and carbonate reached the karst troughs by dissolution of the Late Jurassic Maim limestones

A record of multistage continental break-up on the Brianconnais marginal plateau (Western Alps): Early and Middle-Late Jurassic rifting, 1999, Claudel Me, Dumont T,
The Brianconnais series in the French Western Alps near Briancon bear evidence of extensional deformation preceding Alpine shortening. Most of these structures have been ascribed to Tethyan rifting processes. However, many of them are younger than the initial opening of the Ligurian Tethys ocean (Late Bajocian-Early Bathonian) and have a different orientation than the syn-rift faults. The combined use of sedimentological, stratigraphic, paleostructural and structural methods allows to distinguish the features related to the Tethyan rifting (Early to early Middle Jurassic) from the younger extensional deformation (Late Jurassic) which in part overprinted them: The Tethyan rifting is marked by a subaerial erosional surface (breakup unconformity), bearing karsts which developed along syn-rift faults. The continental to shallow marine diagenetic inprints are analysed (diagenetic log method). The Tethyan syn-rift uplift occurred as pulses from the early Late Triassic (Champcella type units) to the late Early Liassic (Peyre-Haute unit), whereas Tethyan post-rift drowning was synchronous (Late Bathonian thermal subsidence). We propose that the post-break-up extensional deformation (Late Jurassic) is linked with intracontinental rifting of the Atlantic realm (Bay of Biscay and/or Valais rifts). Therefore, the pre-Alpine deformations recorded in the Brianconnais series may result from the interference between different Mesozoic rifting-spreading cycles. Alpine inversion processes are more complex than previously thought since (1) the pre-Alpine structural grain was made of at least two, nearly perpendicular trends, (2) convergence changed in orientation through time, making it possible to reactivate preferentially either one or the other trend, and (3) significant nappe rotations are expected, which may be considered for palinspastic restoration. This has important paleogeographic implications, i.e. the present-day upper units of the Brianconnais pile are not necessarily derived from more distal parts of the Tethyan margin than the lower ones since they may have suffered important lateral, possibly northward, transport before final outward stacking

Karst and caves of Israel, 2001, Frumkin, A.
Israel displays a gradient of karst features from the intensive karstification of Lebanon in the north to practically no karst in Elat region at the southern Negev desert (Gerson, 1976). This is attributed mainly to the climatological gradient from alpine-Mediterranean climate in the Lebanon - Hermon mountains in the north, with precipitation >1000 mm/year, to the extremely arid southern Negev, with <50 mm/year. Another factor is the southward decrease in carbonates/clastics ratio of the phanerozoic stratigraphic section, due to the increasing distance from the Tethys Sea which deposited the significant carbonates. Carbonate rocks outcrop in some 75% of the hilly regions of Israel. They are predominantly of Jurassic to Eocene age. However, much of the carbonates contain marls which inhibit extensive karst development, promoting the dominance of fluviokarst features. Another inhibiting factor is the abundance of faults in the Hermon, Galil and Shomeron regions. The faults are thought to constrain the temporal and spatial continuous underground flow, limiting the development of large caves in these regions. Most limestone caves are relict phreatic conduits and voids, which do not show any genetic relation to subaerial topography. Today these caves are either dry or experience vadose dripwater. These caves have possibly developed under moister conditions than predominate today. Some of them have been sealed from the surface until opened by recent construction activity. They may contain valuable paleoclimatic records (Frumkin, et al., 1994). Vadose caves are also common, and typically experience some water flow and active dissolution during the rainy season. These are mostly composed of vertical shafts with rare horizontal sections. The unique rock salt karst of Mount Sedom exhibits the largest salt caves known in the world. Some sea caves, attributed mainly to wave action with limited dissolution appear in the 'Kurkar' sandstone ridge along the Mediterranean coast. Paleokarst is common in the stratigraphic section, and is probably related to humid paleoclimates. Israel is especially rich in man made caves sustaining abundant fauna, but are beyond the scope of this review.

Genesis of the Dogankuzu and Mortas Bauxite Deposits, Taurides, Turkey: Separation of Al, Fe, and Mn and Implications for Passive Margin Metallogeny, 2002, Ozturk Huseyin, Hein James R. , Hanilci Nurullah,
The Taurides region of Turkey is host to a number of important bauxite, Al-rich laterite, and Mn deposits. The most important bauxite deposits, Do[g]ankuzu and Morta[s], are karst-related, unconformity-type deposits in Upper Cretaceous limestone. The bottom contact of the bauxite ore is undulatory, and bauxite fills depressions and sinkholes in the footwall limestone, whereas its top surface is concordant with the hanging-wall limestone. The thickness of the bauxite varies from 1 to 40 m and consists of bohmite, hematite, pyrite, marcasite, anatase, diaspore, gypsum, kaolinite, and smectite. The strata-bound, sulfide- and sulfate-bearing, low-grade lower part of the bauxite ore bed contains pyrite pseudomorphs after hematite and is deep red in outcrop owing to supergene oxidation. The lower part of the bauxite body contains local intercalations of calcareous conglomerate that formed in fault-controlled depressions and sinkholes. Bauxite ore is overlain by fine-grained Fe sulfide-bearing and calcareous claystone and argillaceous limestone, which are in turn overlain by massive, compact limestone of Santonian age. That 50-m-thick limestone is in turn overlain by well-bedded bioclastic limestone of Campanian or Maastrichtian age, rich with rudist fossils. Fracture fillings in the bauxite orebody are up to 1 m thick and consist of bluish-gray-green pyrite and marcasite (20%) with bohmite, diaspore, and anatase. These sulfide veins crosscut and offset the strata-bound sulfide zones. Sulfur for the sulfides was derived from the bacterial reduction of seawater sulfate, and Fe was derived from alteration of oxides in the bauxite. Iron sulfides do not occur within either the immediately underlying or overlying limestone. The platform limestone and shale that host the bauxite deposits formed at a passive margin of the Tethys Ocean. Extensive vegetation developed on land as the result of a humid climate, thereby creating thick and acidic soils and enhancing the transport of large amounts of organic matter to the ocean. Alteration of the organic matter provided CO2 that contributed to formation of a relatively 12C-rich marine footwall limestone. Relative sea-level fall resulted from strike-slip faulting associated with closure of the ocean and local uplift of the passive margin. That uplift resulted in karstification and bauxite formation in topographic lows, as represented by the Do[g]ankuzu and Morta[s] deposits. During stage 1 of bauxite formation, Al, Fe, Mn, and Ti were mobilized from deeply weathered aluminosilicate parent rock under acidic conditions and accumulated as hydroxides at the limestone surface owing to an increase in pH. During stage 2, Al, Fe, and Ti oxides and clays from the incipient bauxite (bauxitic soil) were transported as detrital phases and accumulated in the fault-controlled depressions and sinkholes. During stage 3, the bauxitic material was concentrated by repeated desilicification, which resulted in the transport of Si and Mn to the ocean through a well-developed karst drainage system. The transported Mn was deposited in offshore muds as Mn carbonates. The sulfides also formed in stage 3 during early diagenesis. Transgression into the foreland basin resulted from shortening of the ocean basin and nappe emplacement during the latest Cretaceous. During that time bioclastic limestone was deposited on the nappe ramp, which overlapped bauxite accumulation

Permo-Mesozoic multiple fluid flow and ore deposits in Sardinia: a comparison with post-Variscan mineralization of Western Europe, 2002, Boni M, Muchez P, Schneider J,
The post-Variscan hydrothermal activity and mineralization in Sardinia (Italy) is reviewed in the framework of the geological and metallogenic evolution of Western Europe. The deposits can be grouped into (a) skarn, (b) high- to low-temperature veins and (c) low-temperature palaeokarst. The structural, stratigraphical and geochemical data are discussed. The results suggest three hydrologically, spatially, and possibly temporally, distinct fluid systems. System 1 (precipitating skarn and high-temperature veins) is characterized by magmatic and/or (?) magmatically heated, meteoric fluids of low-salinity. The source of metals was in the Variscan magmatites, or in the Palaeozoic/Precambrian basement. System 2 (low-temperature veins and palaeokarst) is represented by highly saline, Ca-rich (formation or modified meteoric) fluids. Sources of the metals were the pre-Variscan ores and carbonate rocks. System 3 is characterized by low-temperature, low-salinity fluids of meteoric origin. The hydrothermal deposits related to Systems 1 and 2 can be framed in a crustal-scale hydrothermal palaeofield', characterizing most of the post-orogenic mineralization in Variscan regions of Western and Southern Europe, allowing for local age differences of each single ore district and background effects. The suggested timing for the hydrothermal events in Sardinia is: (1) Mid-Permian (270 Ma), (2) Triassic-Jurassic. It is suggested that the Mesozoic events were related to the onset of Tethys spreading

Paratethyan-Mediterranean connectivity in the Sea of Marmara region (NW Turkey) during the Messinian, 2006, Cagatay Mn, Gorur N, Flecker R, Sakinc M, Tunoglu C, Ellam R, Krijgsman W, Vincent S, Dikbas A,
The Sea of Marmara region is thought to have been a gateway between Paratethys and the Mediterranean since the Middle Miocene, and is therefore an important control on water mass exchange between the two realms. The Miocene successions in the northeastern Aegean and northwestern Marmara regions indicate that the first Mediterranean marine transgression to affect these areas occurred during the late Serravallian.In the northeastern Aegean region, frequent marine incursions occurred during the Tortonian and Messinian stages. The Messinian stage in this area is represented by a package of brackish- to fresh-water carbonates with some marine sandstone-siltstone interbeds (Alcitepe Formation), which conformably overlies the Tortonian Kirazli Formation. The Messinian sequence is overlain with an erosional contact by a shallow marine siliciclastic sequence (Goztepe Formation) of Zanclean age. With its brackish- to fresh-water carbonates and broadly constrained age, the Messinian sequence is interpreted as being coeval with the Upper Evaporite-Lago Mare sequence observed in western Mediterranean basins.In the western Marmara region, the Pontian (Messinian) Alcitepe Formation consists of bioclastic and oolitic limestones with basal clastic rocks. It conformably overlies the fluvio-lacustrine siliciclastic sediments of the Middle to Upper Miocene Kirazli Formation and is overlain by fluvio-lacustrine sediments of the Kimmerian (5.5-3.2[no-break space]Ma) Truva and Tevfikiye formations with an erosional contact.The bioclastic limestones of the Alcitepe Formation in the western Marmara region contain a molluscan and ostracod fauna that are endemic to Paratethys. These fauna indicate deposition in a shallow, brackish- to fresh-water environment. Faunal and paleomagnetic analyses of a section of the Alcitepe Formation at Yenimahalle (Canakkale) confirm that the formation is of Pontian age and represents chron C3r (6.04-5.24[no-break space]Ma). The ostracod analysis indicates that during deposition of the Alcitepe Formation, salinity increased from brackish in the lower part to more saline conditions in the upper part. Ostracod valves have low 87Sr / 86Sr values relative to coeval Late Miocene ocean water. This indicates that exchange between the Sea of Marmara region and the global ocean was restricted throughout this period. Fossil and Sr-isotope evidence suggests, however, that there was a Paratethyan-Marmara connection during the deposition of the lower part of the Alcitepe Formation, with Paratethyan influence reaching the north Aegean. Connection via Marmara between Paratethys and the Mediterranean was not re-established until the late Aktchagylian (Late Pliocene). The re-connection was caused by both increased activity on the North Anatolian Fault and global sea level rise

Identifying Late Miocene episodes of connection and isolation in the Mediterranean-Paratethyan realm using Sr isotopes, 2006, Flecker R, Ellam Rm,
After decades of research, the timing and nature of Late Miocene connections between the Mediterranean, Paratethys and the global ocean are still speculative. The hydrologic flux implications of exchange or isolation are central to all hypotheses for generating the major lithological changes that represent the Messinian Salinity Crisis. Moreover, differences in the hydrologic fluxes envisaged are the primary distinction between models. Despite this, these fluxes remain largely unconstrained. This paper describes the basis for using Sr isotope data innovatively combined with salinity data through hydrologic budget modelling to determine the timing and nature of Mediterranean hydrologic connectivity. We examine the hypotheses for three Late Miocene events to illustrate how this approach allows us to test implied hydrologic scenarios and exclude incompatible models. 1) Pre-evaporite restriction of the Mediterranean; 2) the initiation of salt precipitation; 3) connection between the Sea of Marmara and both Paratethys and the Mediterranean during the Messinian. This process suggests that the Atlantic-Mediterranean exchange was significantly reduced up to three million years before evaporite precipitation. It also indicates that end-member hypotheses for initiating salt precipitation in the Mediterranean (desiccation and connected basin models) are inconsistent with Sr isotope data. A contrasting model where evaporite formation was triggered by Atlantic transgression into a strongly evaporation-dominated Mediterranean is shown to be more compatible with available datasets. The application to Sea of Marmara samples indicates that salinity changes in the basin were not caused by changes to the amount of inflow from either Paratethys or the Mediterranean. Other possible as yet untested applications important for constraining different aspects of the Messinian Salinity Crisis are highlighted

Changing perspectives in the concept of 'Lago-Mare' in Mediterranean Late Miocene evolution, 2006, Orszagsperber Fabienne,
The Cenozoic Alpine orogeny caused the partition of Tethys into several basins. During the Late Neogene, the Mediterranean attained its final configuration, whereas, eastwards, the Paratethys, isolated from the World Ocean, disintegrated progressively into a series of smaller basins. As a result, an endemic fauna developed in these basins, mainly composed of brackish to freshwater faunas, indicating an environment affected by changes in water salinity. These small basins of the Paratethys were named 'Sea-Lakes' by Andrusov [Andrusov, D., 1890. Les Dreissenidae fossiles et actuelles d'Eurasie. Geol. min. 25, 1-683 (in Russian)]. Subsequently this name was translated into 'Lac-Mer' [Gignoux, M., 1936. Geologie stratigraphique, 2[deg]edition, Masson, Paris].In the Mediterranean isolated from the Atlantic at the end of the Miocene (Messinian), thick evaporites deposited, consisting of a marine Lower Evaporite unit and an Upper Evaporite unit, mainly of continental origin. Ruggieri [Ruggieri, G., 1962. La serie marine pliocenica e quaternaria della Val Marecchia. Atti Acad. Sci. Lett. Arti. Palermo, 19, 1-169.] used the term 'Lago-Mare', to characterize the brackish to fresh water environment which occurred within the Mediterranean at the end of the Messinian.During recent decades, numerous scientific investigations concerning the history of the Messinian within the Mediterranean were devoted to the understanding of conditions prevailing after the deposition of the marine evaporites. Brackish to freshwater faunas are found in several outcrops and boreholes in the Mediterranean, both in the uppermost beds of gypsum and inter-bedded within the clastic sediments of the Upper Evaporite Unit, immediately preceeding the flooding by the marine Pliocene waters. These faunas, because of their similarities with the fauna described in the Paratethys, were named 'Paratethyan', or 'Caspi-brackish' fauna, this leading some authors to imply a migration of these fauna from Paratethys to the Mediterranean. However, others refute this hypothesis.New data induced some researchers to consider that exchanges existed between the Mediterranean and the Eastern Paratethys and also between the Mediterranean and the Atlantic Ocean at the Miocene-Pliocene transition. These investigations now take advantage of the accurate time scales established by authors (biostratigraphy, cyclostratigraphy, magnetostratigraphy), allowing good stratigraphic correlations between the Mediterranean and the Paratethys, and precisions on the geodynamic evolution of this area.Furthermore, sediments at the base of the Zanclean (MPl1), locally containing brackish to fresh water faunas conducted authors to attribute this formation to an infra- or pre-Pliocene and also to a Lago-Mare 'event'.Thus, the 'Lago-Mare' concept drifted from its original meaning, and is evolving because of progresses in the understanding of the Mediterranean geodynamics and the adjacent areas during the Miocene-Pliocene transition

The beginning, development and termination of the Middle Miocene Badenian salinity crisis in Central Paratethys, 2006, Peryt Tadeusz Marek,
Middle Miocene Badenian evaporites of the Carpathian region are underlain and overlain by deep-water deposits, the onset of evaporite deposition was sudden but not synchronous in all facies zones and the deposition of evaporites was controlled by the evolution of Carpathian orogen. In the Carpathian Foredeep (and most probably in other basins) the Badenian evaporites represent the lower part of the NN6 zone. Halite and associated deposits in the central part of the Badenian evaporite basin show the same facies successions and marker beds can be traced across and between individual basins. Characteristic marker beds made it possible to correlate various facies zones of the marginal Ca-sulfate platform. These marker beds seem to reflect events that may be related to sudden and widespread changes in water chemistry, which in turn imply major changes in basin hydrology. The onset of the evaporitic deposition in the Carpathian Foredeep was clearly diachronous and the evaporites deposited in the basin centre preceded the beginning of evaporite sedimentation in the marginal basin, however, depositional history in the marginal basin and the basin centre was the same. A general transgressive sequence of evaporites found in the Carpathian Foredeep resulted from the migration of facies zones induced by the nappe movement.Isotopic studies of Badenian foraminifers occurring below evaporites suggest that the interrupted communication of the Paratethys with the ocean was a consequence of eustatic sea-level fall, possibly related to climatic cooling, and it was coupled with a tectonic closure of connection with the Tethys. Thus both tectonics and eustacy have contributed to the origin of salinity crisis. Sedimentological and geochemical data indicate recycling of evaporites throughout most of the evaporite deposition. The recycling at the end of gypsum deposition in the marginal sulfate platform was accompanied by a change in the hydrology of the Central Paratethys that was tectonically-driven, and possibly related to the block tectonic phase manifested in the marginal part of the Carpathian Foredeep Basin. The change in hydrology implied the dilution of brines by inflowing marine water and this terminated the Middle Miocene Badenian salinity crisis. The onset of the Badenian salinity crisis shows great similarities to the onset of the Messinian salinity crisis and the terminations of both crises were different

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