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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 capillary attraction is the adhesive force between a liquid and a solid in capillarity.?

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 magnesite (Keyword) returned 15 results for the whole karstbase:
Showing 1 to 15 of 15
Endellite and Hydromagnesite from Carlsbad Caverns, 1957, Davies William E. , Moore George W.

Origin of ultramafic-hosted magnesite on Margarita Island, Venezuela, 1992, Bujaber N, Kimberley M,

The Late Ordovician-Early Silurian Mallowa Salt of the Carribuddy Group, Canning Basin, north-west Australia, is the largest halite deposit known in Australia, attaining thicknesses of 800 m or more within an area of approximately 200 000 km2. Study of 675 m of drill core from BHP-Utah Minerals' Brooke No. 1 well in the Willara Sub-basin indicates that the Mallowa Salt accumulated within a saltern (dominantly subaqueous evaporite water body) that was subject to recurrent freshening, desiccation and exposure. Textures and bromine signatures imply a shallow water to ephemeral hypersaline environment typified by increasing salinity and shallowing into evaporitic mudflat conditions toward the top of halite-mudstone cycles (Type 2) and the less common dolomite/anhydrite-halite-mudstone cycles (Type 1). The borate mineral priceite occurs in the capping mudstones of some cycles, reinforcing the idea of an increasing continental influence toward the top of mudstone-capped halite cycles. The rock salt in both Type 1 and Type 2 cycles typically comprises a mosaic of large, randomly orientated, interlocking halite crystals that formed during early diagenesis. It only partially preserves a primary sedimentary fabric of vertically elongate crystals, some with remnant aligned chevrons. Intraformational hiati, halite karst tubes and solution pits attest to episodic dissolution. Stacked Type 2 cycles dominate; occasional major recharges of less saline, perhaps marine, waters in the same area produced Type 1 cycles. The envisaged saltern conditions were comparable in many ways to those prevailing during the deposition of halite cycles of the Permian Salado Formation in New Mexico and the Permian San Andres Formation of the Palo Duro Basin area in Texas. However, in the Canning Basin the cycles are characterized by a much lower proportion of anhydrite, implying perhaps a greater degree of continental restriction to the basin. The moderately high level of bromine in the Mallowa Salt (156.5 43.5 ppm Br for primary halite, 146.1 54.7 ppm Br for secondary halite) accords with evolved continental brines, although highly evaporative minerals such as polyhalite and magnesite are absent. The bromine levels suggest little or no dissolution/reprecipitation of primary halite and yet, paradoxically, there is little preservation of the primary depositional fabric. The preservation of early halite cements and replacement textures supports the idea of an early shutdown of brine flow paths, probably at burial depths of no more than a few metres, and the resultant preservation of primary bromine values in the secondary halite

Ironstone is any chemical sedimentary rock with > 15% Fe. An iron formation is a stratigraphic unit which is composed largely of ironstone. The solutes which have precipitated to become ironstone have dissolved from the Earth's surface, from the upper crust, e.g. the basaltic layer of oceanic crust, or from deeper within the Earth. Genetic modellers generally choose between surficial weathering, e.g. soil formation, and hydrothermal fluids which have convected through the upper kilometre of oceanic crust. Most genetic modellers attribute cherty laminated iron formations to hydrothermal convection and noncherty oolitic iron formations to surficial weathering. However, both types of iron formations are attributable to the exhalation of fluids from a source region too deep for convection of seawater. Evidence for a deep source of ferriferous fluids comes from a comparison of ancient ironstone with modern ferriferous sediment in coastal Venezuela. A deep-source origin for ironstone has wide-ranging implications for the origins of other chemical sedimentary ores, e.g. phosphorite, manganostone, bedded magnesite, sedimentary uranium ore, various karst-filling ores, and even petroleum. Preliminary study of a modern oolitic iron deposit described herein suggests that the source of iron and silica to iron formations may have been even deeper than envisioned within most hydrothermal convection models

Microbial communities associated with hydromagnesite and needle-fiber aragonite deposits in a karstic cave (Altamira, northern Spain), 1999, Canaveras Jc, Hoyos M, Sanchezmoral S, Sanzrubio E, Bedoya J, Soler V, Groth I, Schumann P, Laiz L, Gonzalez I, Sainzjimenez C,
Microbial communities, where Streptomyces species predominate, were found in association with hydromagnesite, Mg-5(CO3)(4)(OH)(2). 4H(2)O, and needle-fiber aragonite deposits in an Altamira cave. The ability to precipitate calcium carbonate in laboratory cultures suggests that these and other bacteria present in the cave may play a role in the formation of moonmilk deposits

Extraordinary Features of Lechuguilla Cave, Guadalupe Mountains, New Mexico, 2000, Davis, D. G.
Many unusual features are displayed in Lechuguilla Cave, Guadalupe Mountains, New Mexico, U.S.A. Early speleogenic features related to a sulfuric acid origin of the cave include acid lake basins and subterranean karren fields. Speleogenetic deposits, also products of sulfuric acid origin, include gypsum glaciers and sulfur masses. Features related to convective atmospheric phenomena in the cave include corrosion residues, rimmed vents, and horizontal corrosion/deposition lines. Speleothems of nonstandard origin include rusticles, pool fingers, subaqueous helictites, common-ion-effect stalactites, chandeliers, long gypsum hair, hydromagnesite fronds, folia, and raft cones. Other unusual features discussed are silticles and splash rings.

Geochemistry of Carlsbad Cavern Pool Waters, Guadalupe Mountains, New Mexico, 2000, Forbes, J. R.
Water samples collected from 13 pools in Carlsbad Cavern were analyzed to determine the concentrations of major ions. Air temperature, relative humidity, and carbon dioxide concentration of the cave atmosphere were also measured. Large differences in water quality exist among different cave pools, with some pools containing very fresh water, while others are brackish, with total dissolved solids concentrations up to 5000 mg/L. Brackish water pools appear to be associated with those portions of the cave where evaporation rates are high and/or soluble minerals are present. Geochemical speciation modeling showed that some pools are close to saturation with respect to the common cave minerals aragonite, calcite, gypsum, and hydromagnesite. A tracer test was performed using a non-toxic bromide salt to estimate the leakage rates of selected pools. Pool volumes calculated based on dilution of the bromide tracer were up to 550 m. The tracer test results were used to calculate mean residence times for the water in each pool. Calculated mean residence times based on bromide tracer loss rates ranged from less than a year for Rookery Pool and Devils Spring to 16 years for Lake of the Clouds. Calculated pool leakage rates ranged from 2 L/day to over 100 L/day. The pools with the highest leakage rates appear to be Rookery Pool, Green Lake, and Lake of the Clouds. The long residence times indicated by the tracer tests suggest that the pools evaporate more water than they leak. However, evaporation should result in an accumulation of dissolved chloride and other solutes in the pools, which for most pools does not appear to be the case. Taken together, these observations suggest that the pools are recharged primarily by infrequent precipitation events, separated by long periods of slow evaporation and minimal leakage.

Trioctahedral smectite is a constituent of Mg-rich carbonate crusts and moonmilks (pasty deposits) in caves of the Guadalupe Mountains of southeastern New Mexico. Energy dispersive X-ray microanalysis of individual crystallites and their aggregates along with the X-ray diffraction analysis indicates that the smectite is probably stevensite. Saponite is likely present in some samples also. The smectite is intimately associated with dolomite crusts and huntite moonmilks in Carlsbad Cavern, Lechuguilla Cave, and other dolostone caves. Clay particles appear as fibers and films, with aggregates comprising decimicron-sized filamentous masses that envelop crystals of dolomite, huntite, and magnesite. The occurrence of smectite is related to the genesis of the Mg-rich carbonate minerals. In water films, progressive evaporation and carbon dioxide loss results in the sequential precipitation of Mg-rich calcite, aragonite, dolomite, huntite, and magnesite. This sequence of carbonate precipitation removes Ca and greatly increases the Mg/Ca ratio in the solutions. Silica is commonly available probably because of high pH conditions, and consequently, smectite forms in the Mg-rich alkaline environment. Along with the Mg-rich carbonate minerals, opal, quartz, and uranyl vanadates may precipitate with the smectite

Cave breakdown by vadose weathering, 2002, Osborne R. A. L.
Vadose weathering is a significant mechanism for initiating breakdown in caves. Vadose weathering of ore bodies, mineral veins, palaeokarst deposits, non-carbonate keystones and impure, altered or fractured bedrock, which is intersected by caves, will frequently result in breakdown. Breakdown is an active, ongoing process. Breakdown occurs throughout the vadose zone, and is not restricted to large diameter passages, or to cave ceilings. The surfaces of disarticulated blocks are commonly coated, rather than having fresh broken faces, and blocks continue to disintegrate after separating from the bedrock. Not only gypsum, but also hydromagnesite and aragonite are responsible for crystal wedging. It is impossible to study or identify potential breakdown foci by surface surveys alone, in-cave observation and mapping are essential.

Caves formed within Upper Cretaceous skarns at Baita, Bihor County, Romania: Mineral deposition and speleogenesis, 2002, Onac B. P. ,
The Baita metallogenic district, in Bihor County, Romania, is genetically connected to a deep-seated Upper Cretaceous granitic pluton. Within this district, several bodies of skarn host economic concentrations of Mo, W, Bi, Cu, Pb, Zn, B, wollastonite, and marble. During mining, numerous karst cavities were encountered. Minerals such as wittichenite, antimonian luzonite, natrolite, quartz, chalcanthite, rosasite, glaukosphaerite, aurichalcite, azurite, malachite, norsethite and, more commonly, calcite, aragonite, hydromagnesite, and goethite were found within these skarn-hosted caves as crusts, coralloids, minute crystals, aggregates, and earthy masses. Some of the minerals are of hydrothermal origin, whereas others are interpreted to have formed during episodes of hydrothermal or vadose alteration. A third group consists of minerals that were precipitated from low-temperature karstic waters. Although most skarn-hosted cavities exhibit the classical features of meteoric-water-induced cave, their mineralization, morphology, and position within the skarn support a hydrothermal or a mixed hydrothermal-vadose origin

Groundwater chemical composition changes in the Dubravsky Massif hydrogeological structure, induced by magnesite exploitation, 2004, Bajtos P,
Exploited magnesite bodies of the Dubravsky Massif create parts of karst-fissure aquifer confined by Carboniferous metamorphic rocks of low fissure permeability. Extensive mining progress caused considerable changes in both groundwater circulation and groundwater chemical composition of the aquifer. A model of groundwater chemical composition genesis in such complicated conditions is presented in this paper. Saturation indices (SI) for chosen minerals were computed based on speciation modelling, which indicate oversaturation of groundwater with magnesite, dolomite, calcite, and undersaturation with gypsum in all saturated zone of karst-fissure aquifer. Statistical interpretations of hydrochemical data suppose that anthropogenically unaffected groundwater, where mineralisation is slightly altered by pyrite oxidation in dolomitic environment, represents hydrogeochemical background within the aquifer. It is supposed, that azonic acid, generated by condensation of nitrogen-rich gases freeing by blast-firings in mine, accelerate magnesite and dolomite dissolution. Produced groundwater types are of higher content of NO3, Mg and TIC in comparison with background values. Estimated acceleration of karstification processes due to underground mining is about 1.5 times. In spite of detected contamination, threshold values of drinking water standard, given by the Edict of the Slovak Ministry of Health Care No. 29 / 2002 Z. z. are not markedly exceeded for tested parameters. Future possible exploitation of studied aquifer after mining termination is not excluded

Der Nasse Schacht bei Mannersdorf am Leithagebirge, N (2911/21) - eine thermal beeinflusste Hhle am Ostrand des Wiener Beckens, 2006, Plan L. , Pavuza R. , Seemann R.
The Nasser Schacht ("Wet Pit") was opened and surveyed in 1965 during quarry works. A recent study revealed a thermal influence of this 260 m long and 40 m deep cave. The central part developed along a fissure, with a water puddle at its deepest point, and subhorizontal labyrinthic parts are present as well. Water and air temperatures at the deepest point are ca. 15.5C. The galleries formed probably under phreatic conditions but condensation corrosion also played a significant role in speleogenesis. Striking features are coralloids and popcorn as well as various mineral efflorescences, including calcite, dolomite, dolomite, aragonite, huntite, hydromagnesite, and epsomite. Huntite is here reported from an Austrian cave for the first time. Besides the high temperature also radon and CO2 levels are elevated. The mineralization of the waters in the cave, however, indicates are 'normal' seepage waters distinct from thermal waters of the nearby Mannersdorf thermal spring. Stable isotope analyses of the popcorn speleothems show slight deviations from the figures that could be observed in normal caves and are interpreted as slightly hydrothermal.

Speleothems in the dry Cave Parts of the Gamslcher-Kolowrat Cave, Untersberg near Salzburg (Austria), 2011, Bieniok Anna, Zagler Georg, Brendel Uwe, Neubauer Franz

New, remarkably dry parts of the Gamslöcher-Kolowrat Cave at 728 to 853 m depth have been explored in the Untersberg near Salzburg in Austria. This region is called the Desert, its greatest cavity is called the White Hall. The new cave part is characterized by various white speleothems. The predominant ones are snow-like calcite powder with an extremely low density, and fine gypsum needles. Gypsum also occurs in the form of balls stuck to vertical walls. In addition, fluorescent hydromagnesite crusts, Mg5(CO3)4(OH)2·4H2O, as well as the sodium sulfate mineral mirabilite were identified in this part of the cave. Mirabilite and gypsum needles differ from the gypsum balls in their isotopic sulfur signature (δ34S of -16.9‰ and -18.4‰ vs. +2.9‰). The unusually low sulfur isotopic compositional values are tentatively explained by a source of bacteriogenetic sulfur from sulfides.

Structural and host rock controls on the distribution, morphology and mineralogy of speleothems in the Castanar Cave (Spain), 2011, Alonsozarza A. M. , Martinperez A. , Martingarcia R. , Gilpena I. , Melendez A. , Martinezflores E. , Hellstrom J. , Munozbarco P.

The Castanar Cave (central western Spain) formed in mixed carbonate-siliciclastic rocks of Neoproterozoic age. The host rock is finely bedded and shows a complex network of folds and fractures, with a prevalent N150E strike. This structure controlled the development and the maze pattern of the cave, as well as its main water routes. The cave formed more than 350 ka ago as the result of both the dissolution of interbedded carbonates and weathering of siliciclastic beds, which also promoted collapse of the overlying host rock. At present it is a totally vadose hypergenic cave, but its initial development could have been phreatic. The cave's speleothems vary widely in their morphology and mineralogy. In general, massive speleothems (stalactites, stalagmites, flowstones, etc.) are associated with the main fractures of the cave and bedding planes. These discontinuities offer a fairly continuous water supply. Other branching, fibrous, mostly aragonite speleothems, commonly occur in the steeper cave walls and were produced by capillary seepage or drip water. Detailed petrographical and isotope analyses indicate that both aragonite and calcite precipitated as primary minerals in the cave waters. Primary calcite precipitated in waters of low magnesium content, whereas aragonite precipitated from magnesium-rich waters. Differences in isotope values for calcite (-5.2‰ for ?18O and -9.6‰ for ?13C) and aragonite (?18O of -4.5‰ and ?13C of -3.5‰ ) can be explained by the fact that the more unstable mineral (aragonite) tends to incorporate the heavier C isotope to stabilize its structure or that aragonite precipitates in heavier waters. Changes in the water supply and the chemistry and instability of aragonite caused: (1) inversion of aragonite to calcite, which led to the transformation of aragonite needles into coarse calcite mosaics, (2) micritization, which appears as films or crusts of powdery, opaque calcite, and (3) dissolution. Dolomite, huntite, magnesite and sepiolite were identified within moonmilk deposits and crusts. Moonmilk occurs as a soft, white powder deposit on different types of speleothems, but mostly on aragonite formations. Huntite and magnesite formed as primary minerals, whereas dolomite arose via the replacement of both huntite and aragonite. Owing to its variety of speleothems and location in an area of scarce karstic features, the Castanar Cave was declared a Natural Monument in 1997 and is presently the target of a protection and research programme. Although the main products formed in the cave and their processes are relatively well known, further radiometric data are needed to better constrain the timing of these processes. For example, it is difficult to understand why some aragonite speleothems around 350 ka old have not yet given way to calcite, which indicates that the environmental setting of the cave is still not fully understood. 

The mineralogical study of the Grotta Inferiore di Sant’Angelo (southern Italy), 2014, Catalano M. , Bloise A. , Miriello D. , Apollaro C. , Critelli T. , Muto F. , Cazzanelli E. , Barrese E.

In the present work, thirteen samples collected from the Grotta Inferiore di Sant’Angelo near the town of Cassano allo Jonio (Calabria region, southern Italy) were analyzed for their mineralogy. The Grotta Inferiore di Sant’Angelo is made up of subhorizontal, interlinked galleries between 400 and 450 meters above sea level. The floor is littered with deposits such as bat-guano, gypsum, and many speleothems that also cover the walls. The samples were identified and characterized by X-ray powder diffraction, scanning electron microscopy with energy dispersive spectrometer, microthermometry, and micro-Raman spectroscopy. The ten primary minerals identified in this study belong to six different groups: carbonate, sulfate, apatite, oxide and hydroxide, halide, and silicate. Clay minerals and eight other detrital minerals were also found: enstatite, rutile, magnesite, pyrite, chrysotile, quartz, dolomite, and chlorite. Characterization of cave minerals could be useful to improve the knowledge of the relation between them and the lithology of the host rocks

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