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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 sea estavelle is submarine or sea-shore opening in karst formations which at one season or period discharges ground water (fresh or brackish) from the aquifer into the sea-bed and at another season or period draws seawater into the aquifer by a vacuum [20]. synonyms: (french.) estavelle marine; (german.) submarine estavelle; (greek.) estavelle thalassia (estavella); (italian.) estavella sottomarina, sorgente sottomarina a flusso alterno; (spanish.) estavela marina; (turkish.) sahil batar cikari.?

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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 sr isotopes (Keyword) returned 6 results for the whole karstbase:
Sr isotope study of vein and cave calcites from southern Israel, 1990, Avigour A, Magaritz M, Issar A, Dodson Mh,
The strontium isotope compositions of secondary calcites from the Negev, southern Israel, were compared to those of the marine carbonate host rocks, which range in age from Triassic to Eocene, in order to understand fluid source and migration through fracture systems in dominantly carbonate strata. The Sr isotopes of these calcite clusters are divided into two groups: (1) calcites with 87Sr/86Sr values greater than those of the host carbonates; and (2) calcites with 87Sr/86Sr values close to the values of the host carbonate. 1. (1) These secondary calcites were found on the main tectonic lines of the Negev (faults and fold axes) and are enriched in 87Sr (87Sr/86Sr = 0.707709-0.709151) relative to the marine carbonate country rocks (87Sr/86Sr = 0.707251-0.70755, with one exception). These calcites are associated or crossed by thin veins filled by Fe- and Mn-oxides.2. (2) Secondary calcites with 87Sr/86Sr values close to those of the marine carbonate country rocks (0.7073-0.7077) are found in karstic caves and veins, and are located in sites which are not on the major faults and fold axes. These calcites are not crossed by Fe- and Mn-oxides.The isotopic results indicate that the solutions from which the secondary minerals of the first group precipitated were not in isotopic equilibrium with the marine host rocks. The possible source of the precipitating solutions can be either surface rain descending through the fault system or ascending groundwaters from the deep Nubian aquifer (Paleozoic to Early Cretaceous in age). In both cases there would be a limited interaction with the host sandstone rock which usually is depleted in Sr. The similarity of the 87Sr/86Sr values to those of the host rocks in the second group suggests that the main source of Sr in these calcite crystals was from the dissolution of the marine carbonate country rocks by rain- and flood waters

Geochemistry and water dynamics: Application to short time-scale flood phenomena in a small Mediterranean catchment .1. Alkalis, alkali-earths and Sr isotopes, 1997, Benothman D, Luck Jm, Tournoud Mg,
We report major, trace elements and Sr isotope data for water samples taken regularly during a four-day-long September flood of a Mediterranean river, the Vene (Herault, S. France). The objective is to combine all these data into a dynamic model that describes the origin(s) and movements of waters and their loads. This river drains the runoff from a small, mainly carbonate, partly karstified watershed with Miocene and Jurassic lithologies. The watershed is also impacted by both agricultural and urban activities. Both the dissolved and the particulate loads were analyzed. Concentrations of the dissolved components show major remobilization of almost all elements during the first few hours of the flood (water treatment plants and aerosol scavenging), followed by a sharp concentration decrease. Some major species return to their previous summer values (Ca, HCO3) while others reach low 'background' levels (Na, K, Cl, SO4). Some trace elements (Rb, Sr, Cs) show similar behaviour but (Ba) appears somewhat unaffected. Trace element concentrations and ratios define two main periods (three in the suspended particulate matter). Ratios do not allow distinguishing between the three main sources for the dissolved load in the first period (Miocene, Jurassic, water treatment plants), but clearly show the Jurassic karst influence later on. The Sr-87/Sr-86 Of the suspended particulate matter is more variable and more radiogenic than in the dissolved phase. Variations in concentration ratios and Sr isotope composition in particulates indicate the large and variable contribution of Miocene silicates with some carbonate. However, there is a need for another component with [Rb]/[Sr] higher than bedrocks, internal or external to the watershed, possibly due to differential erosion. Dissolved Ca and Mg fluxes during the flood were calculated at 0.26 ton and 0.029 ton/km(2), respectively. Even though the carbonate nature of the watershed restricts variability in Sr isotope composition in the dissolved load, we distinguish several endmembers: seawater(approximate to marine rain), Miocene marls, Jurassic limestones, water treatment plants (and possibly another attributable to fertilizers). Combined with major and trace element variational Sr isotope fluctuations indicate time-varying proportions of different water endmembers at the outflow and suggest a general dynamic model. Based on PCA (principal component analysis), a 3D representation allows to visualize the geochemical evolution of the Vene waters. In particular, Sr isotopes clearly indicate that the inflow of karstic waters during the flood was not continuous but occurred as a series of marked oscillations between flowing waters with chemical signature of Miocene lithologies and increasing flushes of deeper waters that interacted with Jurassic lithologies. (C) 1997 Elsevier Science B.V

The Sahara-East Mediterranean dust and climate connection revealed by strontium and uranium isotopes in a Jerusalem speleothem, 2004, Frumkin A, Stein M,
This paper explores the potential of Sr and U isotope systems in speleothems as tracers of eolian dust transport and hydrological conditions. The study focuses on a speleothem from Jerusalem spanning the past 220 kyr. This speleothem provides a precisely dated record of dust flux from the Sahara to the East Mediterranean. Enhanced dust flux and Terra Rossa soil development are reflected by elevated 87Sr/86Sr ratios in the speleothem (0.7082-0.7086), while lower 87Sr/86Sr ratios (~0.7078) indicate higher contribution of the local bedrock due to low dust flux and low soil accumulation. The strontium isotope system in the speleothem is a robust monitor of the Sahara monsoon-modulated climate, since dust uptake is related to development or reduction in vegetation cover of Sahara soil. The [234U/238U] activity ratios in the speleothem range between 1.12 and 1.0. The high activity values may indicate selective removal of 234U from the soil while the low values converge to the bedrock. The migration of 234U to the cave reflects mainly the regional hydrological conditions that are modulated by the North Atlantic-Mediterranean climate system. Thus, the speleothem provides a combined record of the monsoon-North Atlantic climatic systems. Long-term stability in glacial 87Sr/86Sr ratios (0.70830.0001 over the past 220 kyr) suggests an overall similarity in eolian dust sources, and uniformity in the synoptic conditions that dominate the dust storm tracks during glacial periods

Concepts and models of dolomitization: a critical reappraisal, 2004, Machel Hans G. ,
Despite intensive research over more than 200 years, the origin of dolomite, the mineral and the rock, remains subject to considerable controversy. This is partly because some of the chemical and/or hydrological conditions of dolomite formation are poorly understood, and because petrographic and geochemical data commonly permit more than one genetic interpretation. This paper is a summary and critical appraisal of the state of the art in dolomite research, highlighting its major advances and controversies, especially over the last 20-25 years. The thermodynamic conditions of dolomite formation have been known quite well since the 1970s, and the latest experimental studies essentially confirm earlier results. The kinetics of dolomite formation are still relatively poorly understood, however. The role of sulphate as an inhibitor to dolomite formation has been overrated. Sulphate appears to be an inhibitor only in relatively low-sulphate aqueous solutions, and probably only indirectly. In sulphate-rich solutions it may actually promote dolomite formation. Mass-balance calculations show that large water/rock ratios are required for extensive dolomitization and the formation of massive dolostones. This constraint necessitates advection, which is why all models for the genesis of massive dolostones are essentially hydrological models. The exceptions are environments where carbonate muds or limestones can be dolomitized via diffusion of magnesium from seawater rather than by advection. Replacement of shallow-water limestones, the most common form of dolomitization, results in a series of distinctive textures that form in a sequential manner with progressive degrees of dolomitization, i.e. matrix-selective replacement, overdolomitization, formation of vugs and moulds, emplacement of up to 20 vol% calcium sulphate in the case of seawater dolomitization, formation of two dolomite populations, and -- in the case of advanced burial -- formation of saddle dolomite. In addition, dolomite dissolution, including karstification, is to be expected in cases of influx of formation waters that are dilute, acidic, or both. Many dolostones, especially at greater depths, have higher porosities than limestones, and this may be the result of several processes, i.e. mole-per-mole replacement, dissolution of unreplaced calcite as part of the dolomitization process, dissolution of dolomite due to acidification of the pore waters, fluid mixing (mischungskorrosion), and thermochemical sulphate reduction. There also are several processes that destroy porosity, most commonly dolomite and calcium sulphate cementation. These processes vary in importance from place to place. For this reason, generalizations about the porosity and permeability development of dolostones are difficult, and these parameters have to be investigated on a case-by-case basis. A wide range of geochemical methods may be used to characterize dolomites and dolostones, and to decipher their origin. The most widely used methods are the analysis and interpretation of stable isotopes (O, C), Sr isotopes, trace elements, and fluid inclusions. Under favourable circumstances some of these parameters can be used to determine the direction of fluid flow during dolomitization. The extent of recrystallization in dolomites and dolostones is much disputed, yet extremely important for geochemical interpretations. Dolomites that originally form very close to the surface and from evaporitic brines tend to recrystallize with time and during burial. Those dolomites that originally form at several hundred to a few thousand metres depth commonly show little or no evidence of recrystallization. Traditionally, dolomitization models in near-surface and shallow diagenetic settings are defined and/or based on water chemistry, but on hydrology in burial diagenetic settings. In this paper, however, the various dolomite models are placed into appropriate diagenetic settings. Penecontemporaneous dolomites form almost syndepositionally as a normal consequence of the geochemical conditions prevailing in the environment of deposition. There are many such settings, and most commonly they form only a few per cent of microcrystalline dolomite(s). Many, if not most, penecontemporaneous dolomites appear to have formed through the mediation of microbes. Virtually all volumetrically large, replacive dolostone bodies are post-depositional and formed during some degree of burial. The viability of the many models for dolomitization in such settings is variable. Massive dolomitization by freshwater-seawater mixing is a myth. Mixing zones tend to form caves without or, at best, with very small amounts of dolomite. The role of coastal mixing zones with respect to dolomitization may be that of a hydrological pump for seawater dolomitization. Reflux dolomitization, most commonly by mesohaline brines that originated from seawater evaporation, is capable of pervasively dolomitizing entire carbonate platforms. However, the extent of dolomitization varies strongly with the extent and duration of evaporation and flooding, and with the subsurface permeability distribution. Complete dolomitization of carbonate platforms appears possible only under favourable circumstances. Similarly, thermal convection in open half-cells (Kohout convection), most commonly by seawater or slightly modified seawater, can form massive dolostones under favourable circumstances, whereas thermal convection in closed cells cannot. Compaction flow cannot form massive dolostones, unless it is funnelled, which may be more common than generally recognized. Neither topography driven flow nor tectonically induced ( squeegee-type') flow is likely to form massive dolostones, except under unusual circumstances. Hydrothermal dolomitization may occur in a variety of subsurface diagenetic settings, but has been significantly overrated. It commonly forms massive dolostones that are localized around faults, but regional or basin-wide dolomitization is not hydrothermal. The regionally extensive dolostones of the Bahamas (Cenozoic), western Canada and Ireland (Palaeozoic), and Israel (Mesozoic) probably formed from seawater that was pumped' through these sequences by thermal convection, reflux, funnelled compaction, or a combination thereof. For such platform settings flushed with seawater, geochemical data and numerical modelling suggest that most dolomites form(ed) at temperatures around 50-80 {degrees}C commensurate with depths of 500 to a maximum of 2000 m. The resulting dolostones can be classified both as seawater dolomites and as burial dolomites. This ambiguity is a consequence of the historical evolution of dolomite research

The Sahara - East Mediterranean dust and climate connection revealed by strontium and uranium isotopes in a Jerusalem speleothem, 2004, Frumkin, A. , And Stein, M.
This paper explores the potential of Sr and U isotope systems in speleothems as tracers of eolian dust transport and hydrological conditions. The study focuses on a speleothem from Jerusalem spanning the past 220 kyr. This speleothem provides a precisely dated record of dust flux from the Sahara to the East Mediterranean. Enhanced dust flux and Terra Rossa soil development is reflected by elevated 87Sr/86Sr ratios in the speleothem (0.7082-6), while lower 87Sr/86Sr ratios (~0.7078) indicate higher contribution of the local bedrock due to low dust flux and low soil accumulation. The strontium isotope system in the speleothem is a robust monitor of the Sahara monsoon-modulated climate, since dust uptake is related to development or reduction in vegetation cover of Sahara soil. The [234U/238U] activity ratios in the speleothem range between 1.12 and 1.0. The high activity values may indicate selective removal of 234U from the soil while the low values converge to the bedrock. The migration of 234U to the cave reflects mainly the regional hydrological conditions that are modulated by the North Atlantic-Mediterranean climate system. Thus, the speleothem provides a combined record of the Monsoon - North Atlantic climatic systems. Long-term stability in glacial 87Sr/86Sr ratios (0.70831 over the past 220 kyr) suggests an overall similarity in eolian dust-sources, and uniformity in the synoptic conditions that dominate the dust storm tracks during glacial periods.

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

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