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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 breakthrough is a quantum jump in erosional activity that is associated with the transition from dominantly laminar to dominantly turbulent flow conditions [9]. see turbulent threshold.?

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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 salinity crisis (Keyword) returned 26 results for the whole karstbase:
Showing 16 to 26 of 26
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

The Messinian Salinity Crisis revisited, 2006, Marie Rouchy Jean, Suc Jean Pierre, Ferrandini Jean, Ferrandini Michelle,

Geodynamic evolution of the peri-Mediterranean karst during the Messinian and the Pliocene: evidence from the Ardeche and Rhone Valley systems canyons, Southern France, 2006, Mocochain Ludovic, Clauzon Georges, Bigot Jean Yves, Brunet Philippe,
During the Messinian-Pliocene eustatic cycle, the Mediterranean Sea was characterized by a short lived (5.95-5.32[no-break space]Ma) sea-level fall, which attained - 1500[no-break space]m in some areas. The study of benchmark levels permits the chronology and dynamics of this event to be established. In the Rhone's middle valley, our investigations allow a new interpretation for the genesis of the Ardeche endokarst. A fall in base-level was responsible for both the incision of the so-called Messinian canyons as well as a deep karst development. Karst systems were formed in association with the Messinian canyons of the Ardeche and Rhone Rivers. During the flooding of the Mediterranean Basin (5.32[no-break space]Ma), these karst systems were filled by water and plugged by sedimentary infilling of the rias. This mechanism pushed groundwater backward through the karst system, which in turn formed diagnostic 'chimney-shafts'. These pathways were geometrically connected to the position of the Pliocene benchmark levels. Consequently, the Messinian Salinity Crisis was responsible for two karst responses.The first was concomitant with the crisis itself and corresponds to the formation of a karst system. The second followed the Messinian Salinity Crisis and corresponds to the adaptation of this karst system in Vauclusian karsts by the formation of 'chimney-shafts'

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

Reconstruction of the paleoenvironmental changes around the Miocene-Pliocene boundary along a West-East transect across the Mediterranean, 2006, Pierre Catherine, Caruso Antonio, Blancvalleron Marie Madeleine, Rouchy Jean Marie, Orzsagsperber Fabienne,
In order to reconstruct the environmental changes at the end of the Messinian salinity crisis, a multidisciplinary study has been carried out with a high sampling resolution of the late Messinian-early Zanclean (Zone MPl 1) sediments along a West-East Mediterranean transect. The studied examples comprise sections from southern Spain (Vera/Almanzora), Balearic Basin (ODP Site 975), Tyrrhenian Basin (ODP Site 974), Sicily (Eraclea Minoa), Zakynthos (Kalamaki), Corfu (Aghios Stefanos), Crete (Aghios Vlasis). Previously analyzed sections from the Levantine Basin (Cyprus and ODP Sites 968 and 969) are used for comparison. The sections have been correlated using planktonic foraminiferal assemblages, sedimentological and stable isotope variations, and compared to the astronomical cyclicity defined in the Miocene-Pliocene boundary stratotype of Eraclea Minoa, Sicily. Variations of CaCO3 content, stable isotopes of carbonates ([delta]18O, [delta]13C), and foraminiferal assemblages indicate similar environmental transition at the Miocene-Pliocene boundary in all of the investigated sections.The latest Messinian deposits are barren of fossils or characterized by only reworked planktonic foraminifers, except for the sporadic presence of Ammonia tepida, brackish or lacustrine ostracods and brackish mollusks typical of the 'Lago-Mare' facies. The oxygen and carbon isotopic compositions of carbonates usually exhibit large variations with dominantly low [delta] values indicating freshwater dilution. The earliest Pliocene (MPl 1, cycle 1) shows a rapid and progressive increase of the [delta]18O values, which indicates the restoration of marine conditions after the Lago-Mare event. Normal marine environments were definitely established and stabilized at the top of cycle 1.These data confirm that the inflow of marine waters occurred contemporaneously within the whole Mediterranean at the base of Pliocene, although stable marine conditions occurred only about 20[no-break space]kyrs later

The Messinian salinity crisis in the Mediterranean basin: A reassessment of the data and an integrated scenario, 2006, Rouchy Jean Marie, Caruso Antonio,
After a long period of controversial debate about the interpretation of the Messinian salinity crisis (MSC), a near consensus existed since the ODP Leg 42A for a model keeping the major lines of the deep basin-shallow water model initially proposed by Hsu et al. (1973). The knowledge of the crisis was improved since the 1995s by the availability of a very accurate astronomically calibrated timescale. The debate about its interpretation was then reactivated by several new scenarios that questioned most the major aspects of the previous classical models. The updated re-examination of the most salient features along with consideration of the hydrological requirements for evaporite deposition allow us to assess the viability of the new models. We propose an integrated scenario that revives the key points of the previous model with new statements about the chronology, depositional settings, hydrological mechanisms, consequences and correlations with the global changes. A model implying two main stages of evaporite deposition that affected successively the whole basin with a slight diachronism matches better the whole dataset. The distribution of the evaporites and their depositional timing were constrained by the high degree of paleogeographical differentiation and by the threshold effects that governed the water exchanges. It is assumed that the central Sicilian basin was a deep basin located in a marginal position with regard to the deepest central basins. The restriction of the Mediterranean was predominantly under a tectonic control, but the complex development of the evaporitic crisis implied the interplay of both glacio-eustatic changes and fluctuations of the circum-Mediterranean climate.The first evaporitic stage (lower evaporites) that includes the deposition of the thick homogeneous halite unit with K-Mg salt interbeds in the deepest basins is correlated with the major evaporative drawdown and higher aridity, and occurred during the glacial period recorded in the ocean sediments between 6.3 and 5.6 Ma. The deposition of the potash in Sicily is tentatively linked to the two major glacial peaks TG 20 and TG 22, while the end of this first stage is linked to the peak TG 12. The second stage (upper evaporites) correlates with the interval of warming and global sea level rise recorded in the ocean since 5.6-5.5 Ma onwards. During this second stage, freshwater contribution increased and culminated by the latest Messinian dilution, i.e. the Lago-Mare event, as the result of the worsened tectonically driven closure of the Atlantic gateways combined to an evolution towards wetter climate conditions at least on the mountainous peripheral areas. In fact, reduced inputs of seawater continued to enter at least episodically the basin through the MSC explaining the sporadic presence of marine organisms. These inputs reached their lowest value and practically ceased during the latest Messinian dilution, just before the abrupt restoration of stable open marine conditions at the beginning of the Zanclean.A polyphased erosional surface affected the Mediterranean margins during the MSC with several critical episodes. The major episode related to the greatest water level fall, more than 1000 m, occurred during the deposition of the lower evaporites, from the onset of the evaporite deposition till the end of the first stage. Erosional processes remained active during the second evaporitic stage especially whenever the basin dried-up and a last important event marked by the karstification of the evaporites developed during the latest Messinian dilution just before the Early Zanclean reflooding that filled the erosional morphology

The deepest cave in the world in the Arabika Massif (Western Caucasus), 2008, Klimchouk A. B. , Samokhin G. V. & Kasjan Yu. M.

Arabika is an outstanding high-mountain karst massif in the Western Caucasus composed of Lower Cretaceous and Upper Jurassic limestones continuously dipping southwest to the Black Sea shore and plunging below the sea level. The central sector (elevations within 2000-2700 m) is characterized by pronounced glacio-karstic landscape and hosts several deep caves including the deepest cave in the world (Krubera-Voronja Cave) recently explored to the depth of -2191 m.  Dye tracing experiments conducted in 1984-1985 revealed that the Krubera Cave area is hydraulically connected with major springs at the Black Sea shore and the submarine discharge, with the flow directed across major fold structures. Krubera Cave has an extremely steep profile and reveals a huge thickness of the vadose zone. Its lower boundary is at elevation of about 110 m, which suggests a very low overall hydraulic gradient of 0.007-0.008. Reported low salinity groundwater tapped by boreholes in the shore area at depths 40-280, 500, 1750 and 2250 m, which suggests the existence of deep flow system with vigorous flow. Submarine discharge in the Arabika coast is reported at depths up to ca. 400 m bsl. Huge closed submarine depression is revealed at the sea-floor in front of Arabika with the deepest point of ca. 400 m bsl. These facts point to a possibility that the main karst system in Arabika could have originated in response to the Messinian salinity crisis (5.96 – 5.33 Myr) when the Black Sea could have almost dried up, similarly to the adjacent Mediterranean where the sea level drop up to 1600 m is well established. Further development of the huge vadose zone and a super-deep cave have been caused by subsequent uplifts during Pliocene-Pleistocene, highly differential between the shore sector (0.1-0.2 km of total uplift) and the central sector (2-2.5 km) of Arabika.


Paleokarst investigation near Saint-Remèze, Ardèche, France: discovery of an underground river fossilised during the Messinian salinity crisis, 2011, Martini, J. E. J.

A number of paleokarst fillings have been investigated. The most important of them represents an ancient underground river. It appears as a sequence of filled passage segments, which have been de-roofed by karst denudation. These segments are developed at 360 to 380 m above sea level and have been followed for 5.2 km. Three distinct cave fillings were put into evidence: 1) beige micaceous silts and sands which represent exogenic immature alluvials and were dated with rodent bones as Uppermost Miocene; 2) mature red clay and sandstone of local origin, whose age might vary from Uppermost Miocene to Recent; 3) monogenic breccia generated by wall gelifraction during the Pleistocene. The petrographic composition of the immature alluvials is similar to the one of the Ardèche River which flows in the vicinity, but deeply entrenched in a canyon, at the altitude of 60-70 m ASL. Therefore, the paleo-underground river was fed by ponors located on the bank of the Ardèche River, when it was flowing more than 300 m higher than its present bed. The weak variations in elevation of the fossil channel suggest a development within the immediate vicinity of the water table. The biostratigraphic age of the immature alluvials as well as the paleokarstic context suggest that the cave was still active ~5.6 to 5.45 Ma ago. In this timespan falls the drastic dryout of the Mediterranean Sea and the beginning of the incision of the Messinian canyons in this area. In general, this fossil water-table cave is also informative on the morphological evolution of the Ardèche Karst and underline the usefulness of palaeontology in dating speleogenesis.


Krubera (Voronja) Cave, 2012, Klimchouk, Alexander

At the dawn of the new millennium, in January 2001, Krubera (Voronja) Cave in the Arabika Massif, Western Caucasus, became the deepest known cave in the world, with a depth of 1710 m. Discovering the first cave on the planet deeper that 2000 m had been a long-standing dream of cavers around the world, and this was set in 2001 as an official goal of the Call of the Abyss project of the Ukrainian Speleological Association (Ukr.S.A.), one of the most ambitious and successful exploration project in the history of speleology. In October 2004 this goal was reached, when Krubera Cave was pushed to depth of −2080 m. In subsequent years, the Ukr.S.A. expeditions have explored the cave to a depth of −2,191 m in the main branch, and also explored the second branch in this cave, called Nekujbyshevskaja, to a depth of −1697 m. The Arabika Massif that hosts Krubera Cave has unique geological and paleogeographic preconditions for the development of a cave with exceptionally high vertical range.


Krubera (Voronja) Cave, 2012, Klimchouk, Alexander

At the dawn of the new millennium, in January 2001, Krubera (Voronja) Cave in the Arabika Massif, Western Caucasus, became the deepest known cave in the world, with a depth of 1710 m. Discovering the first cave on the planet deeper that 2000 m had been a long-standing dream of cavers around the world, and this was set in 2001 as an official goal of the Call of the Abyss project of the Ukrainian Speleological Association (Ukr.S.A.), one of the most ambitious and successful exploration project in the history of speleology. In October 2004 this goal was reached, when Krubera Cave was pushed to depth of −2080 m. In subsequent years, the Ukr.S.A. expeditions have explored the cave to a depth of −2,191 m in the main branch, and also explored the second branch in this cave, called Nekujbyshevskaja, to a depth of −1697 m. The Arabika Massif that hosts Krubera Cave has unique geological and paleogeographic preconditions for the development of a cave with exceptionally high vertical range.


The vertical dimension of karst: controls of vertical cave pattern, 2013, Audra P. , Palmer A. N.

The vertical development of karst is related to the geomorphic evolution of the surrounding landscape. Cave profiles and levels reflect the local fluvial base level and its changes through time. These cave features tend to be preserved far longer than correlative surface features, which are more susceptible to weathering and erosion. As a result, cave morphology offers abundant clues that are helpful in reconstructing the regional geomorphic history. In the vadose zone, water is drawn downward by gravity along vertical fractures. In the phreatic zone, water follows the hydraulic gradient along the most efficient paths to available outlets in nearby valleys. Phreatic passages tend to have gentler gradients close to the water table, generally with some vertical sinuosity. Responding to irregular recharge rates, fluctuations in the water table define a transition zone, the epiphreatic zone, in which passages develop by floodwater flow. Free-surface flow in the vadose zone and full pipe flow in the phreatic zone produce distinctive passage morphologies. Identification of former vadose–phreatic transition zones makes it possible to reconstruct the position of former water tables that represent past static fluvial base levels. Early conceptual models considered cave origin mainly in relation to its position relative to the water table. Later, analytical and digital models showed that dramatic enlargement occurs when dissolutional enlargement of initial fissures is sufficient to allow rapid dissolution and turbulent flow to take place throughout the entire conduit length. Cave development is favored by the widest initial openings, and less importantly by the steepest hydraulic gradients and shortest flow distances. Consequently, most phreatic cave development takes place at or near the water table, but the presence of relatively wide fractures can lead to phreatic loops. Cave levels record successive base-level positions as valleys deepen. The oldest levels in Mammoth Cave (USA) and Clearwater Cave (Malaysia) have been dated beyond 3.5 Ma. However, when base level rises, the deepest parts of the karst are flooded and the flow follows phreatic lifts. In the epiphreatic zone, floodwater produces looping tubes above the low-flow water table. In these last two situations, high-level passages with large vertical loops are not necessarily the oldest. The juvenile pattern, composed of steep vadose passages, is common when soluble rock is first exposed. In perched aquifers, vadose erosion can produce very large cross sections. In dammed aquifers, the main drain is established at the water table. Irregular recharge causes backflooding, and passages develop throughout the epiphreatic zone, with looping profiles; however, when recharge is fairly regular, the passages develop along the stable water table. Interconnected cave levels correspond to some of the largest cave systems in the world. When base level rises, the karst is flooded; water rises through phreatic lifts and discharges at vauclusian springs. A per ascensum speleogenesis can produce higher-elevation passages that are younger than passages at lower elevations. Base-level rises occur after tectonic subsidence, filling of valleys, or sea-level rise, especially around the Mediterranean in response to the Messinian Salinity Crisis. Deep-phreatic karst, if not hypogenic, can generally be attributed to flooding by a base-level rise. 


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