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Enviroscan Ukrainian Institute of Speleology and Karstology


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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 open traverse is a traverse which does not close onto a survey point of known coordinates and orientation or onto itself [25].?

Checkout all 2699 terms in the KarstBase Glossary of Karst and Cave Terms


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KarstBase a bibliography database in karst and cave science.

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 redox (Keyword) returned 36 results for the whole karstbase:
Showing 1 to 15 of 36
Microorganisms in Australian caves and their influence on speleogenesis, 1994,
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James J. M.

A model of speleogenic processes connected with bacterial redox in sulfur cycles in the caves of Kugitangtau Ridge, Turkmenia, 1994,
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Korshunov V. , Semikolennyh A.

Cenote Verde: a mero-mictic karst pond, Quintana Roo, Mexico, 1994,
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Wilson W. L. , Morris T. L.

Classification of cave dypsum deposits derived from oxidation of H2S, 1994,
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Buck M. J. , Ford D. C. , Schwarcz H. P.

Elemental sulfur in caves of the Guadalupe Mountains, New Mexico, 1994,
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Cunningham K. I. , Duchene H. R. , Spirakis C. S. , Mclean J. S.

Sulfur redox reactions: hydrocarbons, native sulfur, Mississippi Valley-type deposits sulfuric acid karst in the Delaware Basin, New Mexico and Texas., 1995,
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Hill C. A.

Sulfur redox reactions: Hydrocarbons, native sulfur, Mississippi Valley-type deposits, and sulfuric acid karst in the Delaware Basin, New Mexico and Texas, 1995,
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Hill C. ,

Thermodynamic equilibrium, kinetics, activation barriers, and reaction mechanisms for chemical reactions in Karst Terrains, 1997,
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White W. B. ,
Chemical reactions pertinent to karst systems divide broadly into (a) speciation reactions within aqueous solutions, (b) dissolution/precipitation and other acid/base reactions between aqueous solutions and solid minerals, and (c) redox reactions involving various carbon and sulfur-bearing species. As a backdrop against which other chemistry can be evaluated, selected phase diagrams and equilibrium speciation diagrams were calculated for the system Ca--Mg--O--H--C--S. The kinetics of reactions within this system span time scales from milliseconds for homogeneous reactions in solution through hundreds of hours for carbonate mineral dissolution reactions, to geologic time scales for reactions such as the aragonite/calcite inversion or the oxidation/reduction of native sulfur. In purely inorganic systems, kinetic barriers, typically on the order of tens of kJ/mole, are set by nucleation processes and by activated complex formation. Biological processes impact the purely inorganic chemistry by the following mechanisms: (a) Secretions and waste products from biological activity or consumption of CO2 by organisms changes the chemistry in the microenvironments of reaction surfaces. Oxidation potentials, pH, and ion activities may be modified, thus shifting equilibria. (b) Reaction rates may be increased due to modification of activated complexes and thus the activation barriers to reaction. (c) Organic compounds or microorganisms may act as substrates, thus lowering nucleation barriers. The preservation of microorganisms in cave deposits does not necessarily prove a cause and effect relationship

Controls on bacterial sulphate reduction in a dual porosity aquifer system: the Lincolnshire Limestone aquifer, England, 2000,
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Bottrell Sh, Moncaster Sj, Tellam Jh, Lloyd Jw, Fisher Qj, Newton Rj,
Chemical and sulphur isotopic analyses are presented of fissure-waters and pore-waters in the deep confined zone of a dual porosity carbonate aquifer. Some of the fissure-waters show good evidence for bacterial sulphate reduction, with low concentrations of sulphide present which is strongly to moderately depleted in 34S relative to sulphate. The sulphur geochemistry is best interpreted as mixing between: (i) a reduced water with sulphide ~60[per mille sign] depleted in 34S relative to sulphate; and (ii) a sulphate-rich water from up-dip in the aquifer. In addition, sulphide oxidation occurs where sufficiently oxidizing water is drawn in by abstractions. The large isotope fractionation factor associated with the sulphidic waters is probably the result of redox cycling of sulphur with little net reduction, rather than a true kinetic fractionation factor. By contrast, pore-waters in the 'sulphate reducing zone' show little or no evidence for the effects of sulphate reduction, despite the fact that the pore-waters represent a significant reservoir of sulphate for reduction. Some pore-waters have been modified recognizably by diffusional exchange with the fissure-waters, but the aquifer matrix has not been colonized by sulphate reducing bacteria, probably because porethroats in the limestone are too small for bacteria to pass. Physical exclusion of bacteria from the aquifer matrix and limited diffusional exchange are likely to exert fundamental controls on bacterial redox processes in dual porosity aquifer systems and other systems with low permeability due to small pore interconnections

Microbiology and geochemistry in a hydrogen-sulphide-rich karst environment, 2000,
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Hose Louise D. , Palmer Arthur N. , Palmer Margaret V. , Northup Diana E. , Boston Penelope J. , Duchene Harvey R. ,
Cueva de Villa Luz, a hypogenic cave in Tabasco, Mexico, offers a remarkable opportunity to observe chemotrophic microbial interactions within a karst environment. The cave water and atmosphere are both rich in hydrogen sulphide. Measured H2S levels in the cave atmosphere reach 210 ppm, and SO2 commonly exceeds 35 ppm. These gases, plus oxygen from the cave air, are absorbed by freshwater that accumulates on cave walls from infiltration and condensation. Oxidation of sulphur and hydrogen sulphide forms concentrated sulphuric acid. Drip waters contain mean pH values of 1.4, with minimum values as low as 0.1.The cave is fed by at least 26 groundwater inlets with a combined flow of 200-300 l/s. Inlet waters fall into two categories: those with high H2S content (300-500 mg/l), mean PCO2=0.03-0.1 atm, and no measurable O2; and those with less than 0.1 mg/l H2S, mean PCO2=0.02 atm, and modest O2 content (up to 4.3 mg/l). Both water types have a similar source, as shown by their dissolved solid content. However, the oxygenated water has been exposed to aerated conditions upstream from the inlets so that original H2S has been largely lost due to outgassing and oxidation to sulphate, increasing the sulphate concentration by about 4%. Chemical modelling of the water shows that it can be produced by the dissolution of common sulphate, carbonate, and chloride minerals.Redox reactions in the cave appear to be microbially mediated. Sequence analysis of small subunit (16S) ribosomal RNA genes of 19 bacterial clones from microbial colonies associated with water drips revealed that 18 were most similar to three Thiobacilli spp., a genus that often obtains its energy from the oxidation of sulphur compounds. The other clone was most similar to Acidimicrobium ferrooxidans, a moderately thermophilic, mineral-sulphide-oxidizing bacterium. Oxidation of hydrogen sulphide to sulphuric acid, and hence the cave enlargement, is probably enhanced by these bacteria.Two cave-enlarging processes were identified. (1) Sulphuric acid derived from oxidation of the hydrogen sulphide converts subaerial limestone surfaces to gypsum. The gypsum falls into the cave stream and is dissolved. (2) Strongly acidic droplets form on the gypsum and on microbial filaments, dissolving limestone where they drip onto the cave floors.The source of the H2S in the spring waters has not been positively identified. The Villahermosa petroleum basin within 50 km to the northwest, or the El Chichon volcano [small tilde]50 km to the west, may serve as source areas for the rising water. Depletion of 34S values (-11.7[per mille sign] for sulphur stabilized from H2S in the cave atmosphere), along with the hydrochemistry of the spring waters, favour a basinal source

Geomicrobiology and redox geochemistry of the karstified Miocene gypsum aquifer, Western Ukraine: A study from Zoloushka Cave., 2001,
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Andrejchuk V. N. , Klimchouk A. B.
The gypsum karst of the western Ukraine developed largely under artesian conditions. The Miocene aquifer is presently entrenched and dewatered over much of the territory, while it remains confined in the zone adjacent to the Carpathian Foredeep. The most prominent geochemical features of the Miocene aquifer system in the confined karst zone are: 1) the almost universal presence of a bioepigenetic calcite bed, enriched in the light carbon isotope, at the top of the gypsum (the "Ratynsky Limestone"), 2) the widespread sulfur mineralization associated with the above calcite bed (the region is one of the world's largest sulfur-bearing basins), and 3) high H2S and CO2 in the groundwater. Intense microbial sulfate-reduction processes occur in the gypsum in this zone. Zoloushka Cave is the third longest (92 km) and the largest by volume (more than 7 x 105 m3) gypsum cave in the world. It is a unique example of a young artesian cave that only during the Holocene became partly drained and during the last 50 years progressively dewatered due to a quarry operation. These rapid changes have induced a number of transitional geochemical processes, some of which appear to be bacterially mediated. Six groups of microorganisms have been identified in the cave. The paper discusses the aquifer geochemistry during the transitional stage in the light of the microbiological studies.

Geomicrobiology and redox geochemistry of the karstified Miocene gypsum aquifer, western Ukraine: The study from Zoloushka Cave, 2001,
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Andrejchuk Vn, Klimchouk Ab,
The gypsum karst of the western Ukraine developed largely under artesian conditions. The Miocene aquifer is presently entrenched and dewatered over much of the territory, while it remains confined in the zone adjacent to the Carpathian Foredeep. The most prominent geochemical features of the Miocene aquifer system in the confined karst zone are: (1) the almost universal presence of a bioepigenetic calcite bed, enriched in the light carbon isotope, at the top of the gypsum (the 'Ratynsky Limestone'), (2) the widespread sulfur mineralization associated with the above calcite bed (the region is one of the world's largest sulfur-bearing basins), and (3) high H2S and CO2 in the groundwater. Intense microbial sulfate-reduction processes occur in the gypsum in this zone. Zoloushka Cave is the third longest (92 km) and the largest by volume (more than 7 x 10(5) m(3)) gypsum cave in the world. It is a unique example of a young artesian cave that only during the Holocene became partly drained and during the last 50 years progressively dewatered due to a quarry operation. These rapid changes have induced a number of transitional geochemical processes, some of which appear to be bacterially mediated. Six groups of microorganisms have been identified in the cave. Our article discusses the aquifer geochemistry during the transitional stage in the light of the microbiological studies

Geomicrobiology of caves: A review, 2001,
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Northup D. E. , Lavoie K. H. ,
In this article, we provide a review of geomicrobiological interactions in caves, which are nutrient-limited environments containing a variety of redox interfaces. Interactions of cave microorganisms and mineral environments lead to the dissolution of, or precipitation on, host rock and speleothems (secondary mineral formations). Metabolic processes of sulfur-, iron-, and manganese-oxidizing bacteria can generate considerable acidity, dissolving cave walls and formations. Examples of possible microbially influenced corrosion include corrosion residues (e.g., Lechuguilla and Spider caves, New Mexico, USA), moonmilk from a number of caves (e.g., Spider Cave, New Mexico, and caves in the Italian Alps), and sulfuric acid speleogenesis and cave enlargement (e.g., Movile Cave, Romania, and Cueva de Villa Luz, Mexico). Precipitation processes in caves, as in surface environments, occur through active or passive processes. In caves, microbially induced mineralization is documented in the formation of carbonates, moonmilk, silicates, clays, iron and manganese oxides, sulfur, and saltpeter at scales ranging from the microscopic to landscape biokarst. Suggestions for future research are given to encourage a move from descriptive, qualitative studies to more experimental studies

Palaeo-mixing zone karst features from Palaeocene carbonates of north Spain: criteria for recognizing a potentially widespread but rarely documented diagenetic system, 2001,
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Bacetaa J. I. , Wrightb V. P. , Pujalte V.

Marine-meteoric mixing zone dissolution effects are a major feature of present day karst systems in carbonate platforms,yet are rarely reported in the geological record. An example is described from the upper Danian platform limestones of the Alava province,in  the western Pyrenees,north Spain. This consists of several narrow zones with sponge-like porosity analogous to the "Swiss-cheese" features found in present day mixing  zones. These zones are stained by Fe-oxides and overlie limestones which are irregularly  dolomitized  and contain disseminated pyrite. These high-porosity  zones are interpreted as having developed in marine mixing zones where mixing corrosion and microbially  mediated processes increased dissolution. If collapsed,ancient mixing zones could be misinterpreted as "terra-rossa" palaeosols. The main criteria to identify them as mixing zone products are their occurrence below a palaeo-meteoric phreatic zone,their association with stratified oxic and anoxic redox zones and petrographic evidence for highly variable calcite saturation states.


Palaeo-mixing zone karst features from Palaeocene carbonates of north Spain: criteria for recognizing a potentially widespread but rarely documented diagenetic system , 2001,
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Baceta J. I. , Wrightb V. P. , Pujaltec V.

Marine-meteoric mixing zone dissolution effects are a major feature of present day karst systems in carbonate platforms,yet are rarely reported in the geological record. An example is described from the upper Danian platform limestones of the Alava province,in the western Pyrenees,north Spain. This consists of several narrow zones with sponge-like porosity analogous to the "Swiss-cheese" features found in present day mixing zones. These zones are stained by Fe-oxides and overlie limestones which are irregularly dolomitized and contain disseminated pyrite. These high-porosity zones are interpreted as having developed in marine mixing zones where mixing corrosion and microbially mediated processes increased dissolution. If collapsed,ancient mixing zones could be misinterpreted as "terra-rossa" palaeosols. The main criteria to identify them as mixing zone products are their occurrence below a palaeo-meteoric phreatic zone,their association with stratified oxic and anoxic redox zones and petrographic evidence for highly variable calcite saturation states


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