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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 Darcian velocity; seepage velocity is see specific discharge.?

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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 salinity (Keyword) returned 101 results for the whole karstbase:
Showing 91 to 101 of 101
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.


Imprints of hydrocarbon-bearing basinal fluids on a karst system: mineralogical and fluid inclusion studies from the Buda Hills, Hungary, 2011, Poros Zsofia, Mindszenty Andrea, Molnar Ferenc, Pironon Jacques, Gyori Orsolya, Ronchi Paola, Szekeres Zoltan

Calcite veins and related sulphate–sulphide mineralisation are common in the Buda Hills. Also, abundant hypogenic caves are found along fractures filled with these minerals pointing to the fact that young cave-forming fluids migrated along the same fractures as the older mineralising fluids did. The studied vein-filling paragenesis consists of calcite, barite, fluorite and sulphides. The strike of fractures is consistent—NNW–SSE—concluding a latest Early Miocene maximum age for the formation of fracture-filling minerals. Calcite crystals contain coeval primary, hydrocarbon-bearing- and aqueous inclusions indicating that also hydrocarbons have migrated together with the mineralising fluids. Hydrocarbon inclusions are described here for the first time from the Buda Hills. Mixed inclusions, i.e., petroleum with ‘water-tail’, were also detected, indicating that transcrystalline water migration took place. The coexistence of aqueous and petroleum inclusions permitted to establish the entrapment temperature (80°C) and pressure (85 bar) of the fluid and thus also the thickness of sediments, having been eroded since latest Early Miocene times, was calculated (800 m). Low salinity of the fluids (<1.7 NaCl eq. wt%) implies that hydrocarbon-bearing fluids were diluted by regional karst water. FT-IR investigations revealed that CO2 and CH4 are associated with hydrocarbons. Groundwater also contains small amounts of HC and related gases on the basin side even today. Based on the location of the paleo- and recent hydrocarbon indications, identical migration pathways were reconstructed for both systems. Hydrocarbon-bearing fluids are supposed to have migrated north-westward from the basin east to the Buda Hills from the Miocene on.


Fluid migration and porosity evolution in the Buda Hills, Hungary – selected examples from Triassic and Paleogene carbonate rocks/Dissertation submitted to the Ph.D. program for Geology and Geophysics at the Ph.D. School of Earth Sciences, Eötvös Lor, 2011, Poros, Zsófia

Porosity evolution of carbonates in the Buda Hills was the subject of this research. The aim was to provide an analogue for carbonate reservoirs that underwent multiphase diagenesis. Two major porosity types were recognized: 1) micro-porosity of powdered Triassic dolomites 2) cavernous and fracture porosity represented by the famous hypogenic cave system, hosted by Triassic and Paleogene carbonates. Powderization of dolomite is a general phenomenon in the Buda Hills, where its areal extent is exceptionally large compared to similar occurrences elsewhere in the world. Geochemistry and mineralogy of the dolomite remained constant throughout the disintegration. Powderization is absent at places where the Triassic dolomites are partially calcitized as a result of karst related dedolomitization. Since powderization was controlled by surface related processes and no geochemical changes were associated with it, disintegration of dolomite is interpreted as the result of sub-recent physical weathering, supposedly related to frost action.

Hypogenic caves are found along older calcite-barite-fluorite-sulphide veins, pointing to the fact that young cave-forming fluids migrated along the same fractures as the older mineralizing fluids did. Predominantly NNW–SSE strike of fractures concludes a latest Early Miocene maximum age for the fracture-filling minerals. Vein-calcite contains coeval primary, HC-bearing- and aqueous inclusions indicating that also HCs have migrated together with the mineralizing fluids. The coexistence of aqueous and HC inclusions permitted to establish the entrapment temperature (80°C) and pressure (85 bar) of the fluid and thus also the thickness of sediments, having been eroded since latest Early Miocene times, was calculated (800 m). Low salinity of the fluids (<1.7 NaCl eq. wt%) implies that HC-bearing fluids were diluted by regional karst water. Fluid inclusion studies also revealed that aggressive gases (e.g. CO2, H2S) were associated with HCs and that these gases may have played a role in dissolution of the carbonates. Based on the location of the paleo- and recent HC indications, identical migration pathways were reconstructed for both systems. It was proved that HC-bearing fluids have migrated northwestward from the basin east to the Buda Hills from the Miocene on. Due to the uplift related intensification of groundwater circulation, the proportion of hydrothermal fluids has diminished in favour of cold meteoric fluids. Establishment of the actual porosity of the Buda Karst initiated in Miocene times and earlier diagenetic history of the carbonates affected only the powderization of dolomite, and it had no direct effect on the localization of hypogenic caves.


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.


Water supply spring zone Novljanska Zrnovnica (Croatia) new quantities of drinking water in the conditions of salt water intrusion, 2012, Biondić, R. , Biondić, B. , Measki H.

This paper presents an approach for solving the problem of exploitation of freshwater in the coastal karst aquifer during summer dry periods in the conditions of potential salt water intrusion. The approach is presented on the example of spring zone Novljanska Zrnovnica, situated in the northern part of Croatian Adriatic coastal region. The spring zone is used for water supply (about 250 l/s) of an important tourist area of Crikvenica and Novi Vinodolski. After unsuccessful attempts of physical separation of freshwater system from the sea influence, by construction of grout curtain, hydrogeological studies have focused on the possibility of groundwater capturing in the hinterland of discharge zone, outside of the zone of periodical salinity. The final research results with the exploitation well in the spring hinterland can serve as a model for research and exploitation of drinking water in natural conditions of unstable freshwater-saltwater interface in similar natural conditions.


Water supply spring zone Novljanska rnovnica (Croatia) new quantities of drinking water in the conditions of salt water intrusion, 2012, Biondić, Ranko, Biondić, Boidar, Meaki Hrvoje

This paper presents an approach for solving the problem of exploitation of freshwater in the coastal karst aquifer during summer dry periods in the conditions of potential salt water intrusion. The approach is presented on the example of spring zone Novljanska rnovnica, situated in the northern part of Croatian Adriatic coastal region. The spring zone is used for water supply (about 250 l/s) of an important tourist area of Crikvenica and Novi Vinodolski. After unsuccessful attempts of physical separation of freshwater system from the sea influence, by construction of grout curtain, hydrogeological studies have focused on the possibility of groundwater capturing in the hinterland of discharge zone, outside of the zone of periodical salinity. The final research results with the exploitation well in the spring hinterland can serve as a model for research and exploitation of drinking water in natural conditions of unstable freshwater-saltwater interface in similar natural conditions.

 

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. 


Geochemistry and isotope geochemistry of the Monfalcone thermal waters (northern Italy): inference on the deep geothermal reservoir, 2013, Petrini R. , Italiano F. , Ponton M. , Slejko F. F. , Aviani U. , Zini L.

Geochemical investigations were carried out to define the origin of the low- to moderate-temperature thermal waters feeding the Monfalcone springs in northern Italy. Chemical data indicate that waters approach the composition of seawater. Mixing processes with cold low-salinity waters are highlighted. The δ18O and δD values are in the range −5.0 to −6.4 ‰, and −33 to −40 ‰, respectively, suggesting the dilution of the saline reservoir by karst-type freshwaters. A surplus of Ca2+ and Sr2+ ions with respect to a conservative mixing is ascribed to diagenetic reactions of the thermal waters with Cretaceous carbonates at depth. The measured Sr isotopic composition (87Sr/86Sr ratio) ranges between 0.70803 and 0.70814; after correction for the surplus Sr, a 87Sr/86Sr ratio indicating Miocene paleo-seawater is obtained. The dissolved gases indicate long-lasting gas–water interactions with a deep-originated gas phase of crustal origin, dominated by CO2 and marked by a water TDIC isotopic composition in the range −5.9 to−8.8 and helium signature with 0.08 < R/Ra < 0.27, which is a typical range for the crust. A possible scenario for the Monfalcone thermal reservoir consists of Miocene marine paleowaters which infiltrated through the karstic voids formed within the prevalently Cretaceous carbonates during the upper Eocene emersion of the platform, and which were entrapped by the progressive burial by terrigenous sediments.


Groundwater geochemistry observations in littoral caves of Mallorca (western Mediterranean): implications for deposition of phreatic overgrowths on speleothems., 2014, Boop L. M. , Onac B. P. , Wynn J. G. , Fornós J. J. , Rodríguezhomar M. , Merino A.

Phreatic overgrowths on speleothems (POS) precipitate at the air-water interface in the littoral caves of Mallorca, Spain. Mainly composed of calcite, aragonite POS are also observed in specific locations. To characterize the geochemical environment of the brackish upper water column, water samples and salinity values were collected from water profiles (0-2.9 m) in April 2012 and March 2013 near aragonite POS in Cova des Pas de Vallgornera and calcite POS in Coves del Drac (hereafter, Vallgornera and Drac). Degassing of CO2 from the water was evidenced by the existence of lower dissolved inorganic carbon (DIC) concentration and enriched δ13CDIC values in a thin surface layer (the uppermost 0.4 m), which was observed in both profiles from Drac. This process is facilitated by the efficient exchange of cave air with the atmosphere, creating a CO2 partial pressure (pCO2) disparity between the cave water and air, resulting in the precipitation of calcite POS as CO2 degasses from the water. The degassed upper layer was not observed in either profile from Vallgornera, suggesting that less efficient cave ventilation restricts outgassing of CO2, which also results in accumulation of CO2 in the cave atmosphere. The presence of an existing uncorroded POS horizon, as well as higher concentrations and large amplitude fluctuations of cave air pCO2, may indicate that aragonite POS deposition is currently episodic in Vallgornera. Ion concentration data from monthly water samples collected in each cave between October 2012 and March 2013 indicate higher Mg:Ca, Sr:Ca, Ba:Ca and Sr:Mg ratios in Vallgornera. Salinity alone does not appear to be a viable proxy for ions that may promote aragonite precipitation or inhibit calcite precipitation. Instead, these ions may be contributed by more intense bedrock weathering or deep groundwater flow.


Deep speleological salt contamination in Mediterranean karst aquifers: perspectives for water supply, 2015,

On the Mediterranean coast, submarine karst springs are common. Most of them are brackish and various unsuccessful attempts in France, Greece, and Italy indicate that it is impossible to diminish the salinity at the spring. Based on studies on the shores of south-eastern France and in Kefalonia (Greece), we propose a working model that explains the mechanism of salt contamination. During the Messinian Deep Stage (-5.9 to 5.3 Ma), a substantial sea-level lowering in the Mediterranean allowed the existence of cave networks extending several hundreds of meters below the present sea level. Seawater is now sucked into the system through these caves. This mechanism is supported by a study of the Port Miou underground river (Cassis, France). In the Port Miou cave system, which extends to 250 m below sea level, titanium and heavy metals are present in the sediment. They are similar to those found in the Cassidaigne submarine canyon, which reinforces the hypothesis of a connection between the cave and the canyon. Recent geological studies prove a Messinian origin for the canyon and support the deep contamination model. The model is also supported by examples on Kefalonia Island (Greece) and in the Toix–Moraig system (Spain) where salt-water intrusions are observed in coastal sinkholes and sea caves. This model explains why various attempts to diminish the salinity of these brackish springs, through the construction of dams to increase head, have failed.On the Mediterranean coast, submarine karst
springs are common. Most of them are brackish and various
unsuccessful attempts in France, Greece, and Italy
indicate that it is impossible to diminish the salinity at the
spring. Based on studies on the shores of south-eastern
France and in Kefalonia (Greece), we propose a working
model that explains the mechanism of salt contamination.
During the Messinian Deep Stage (-5.9 to 5.3 Ma), a
substantial sea-level lowering in the Mediterranean
allowed the existence of cave networks extending several
hundreds of meters below the present sea level. Seawater is
now sucked into the system through these caves. This
mechanism is supported by a study of the Port Miou
underground river (Cassis, France). In the Port Miou cave
system, which extends to 250 m below sea level, titanium
and heavy metals are present in the sediment. They are
similar to those found in the Cassidaigne submarine canyon,
which reinforces the hypothesis of a connection
between the cave and the canyon. Recent geological
studies prove a Messinian origin for the canyon and support
the deep contamination model. The model is also
supported by examples on Kefalonia Island (Greece) and in
the Toix–Moraig system (Spain) where salt-water intrusions
are observed in coastal sinkholes and sea caves. This
model explains why various attempts to diminish the
salinity of these brackish springs, through the construction
of dams to increase head, have failed.


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