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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 carbonate is 1. a salt or ester of carbonic acid; a compound containing the radical 31 co3 -2, such as calcium carbonate, caco3.2. a rock consisting mainly of carbonate minerals, such as limestone or dolomite [10].?

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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 hypogen (Keyword) returned 376 results for the whole karstbase:
Showing 31 to 45 of 376
Central Aldan gold deposits, 2002, Vetluzhskikh V. G. , Kazansky V. I. , Kochetkov A. Y. , Yanovsky V. M. ,
The Central Aldan ore district stands out in many features against the other gold districts within the Aldan Shield. The gold, uranium, and other mineral deposits are located at a junction of regional structures, they originated within a relatively short time interval of about 100 Ma, the ore mineralization is closely spatially and genetically related to alkaline magmatism, the igneous rocks and related ore deposits are located within a concentric-radial structure, and the host rocks consist of basement and sedimentary cover contrasting in physicochemical properties. All these features allow us to consider the Central Aldan district as an endogenous ore-magmatic system. The Aldan complex of primarily ore-bearing alkaline basaltic crustal-mantle volcanic and plutonic rocks originated during four to five stages and numerous intrusive phases and extensive magma differentiation in mature continental crust including thin horizontally heterogeneous platform cover. Some facts considered in this paper allowed us, however, to comprise the whole series of Central Aldan gold deposits as an endogenous-exogenous ore-forming system characteristic of the tectonically activated regions of ancient platforms. The evolution of the Central Aldan district in the Jurassic, Cretaceous, and Cenozoic developed during the tectonic activation of Precembrian structures, oxidation of primary ores and weathering crust formation, and exposure of the Lebedinsk-, Kuranakh-, Ryabinovsk-, and Samolazovsk-type gold deposits to the erosion level. The formation of underground and surficial karst systems was initiated during the Jurassic weathering of carbonate rocks of the platform cover in subaerial environments. The endogenous stage of ore concentration was here directly followed by an exogenous stage with the formation of weathered rocks and gold placers in various morphostructural local environments, e.g., horsts, grabens, and graben valleys. Specific features of the placer structures and gold, quality in various placer types are related with hypogene ore bodies and elements of ore-controlling structures and zones of primary disseminated mineralization. The ore bodies of the Kuranakh and Samolazovskoe deposits actually belong to new types of endogenous-exogenous deposits. The gold dispersion and concentration related to karst formation are also significant in this ore district. Thus, Central Aldan is also an ore-placer district with specific features

Hypogenic caves in Provence (France). Specific features and sediments, 2002, Audra Philippe, Bigot Jeanyves, Mocochain Ludovic

Two dry caves from French Provence (Adaouste and Champignons caves) were until now considered as "normal" caves having evolved under meteoric water flow conditions. A new approach gives evidence of a hypogenic origin from deep water uprising under artesian conditions. Specific morphologies and sediments associated with this hydrology are discussed.

Gypsum deposits in the Frasassi Caves, central Italy, 2003, Galdenzi, S. , Maruoka, T.
The Frasassi Caves are hypogenic caves in central Italy, where H2S-rich groundwater flows in the lowest cave level. Near the water table, the H2S is converted to sulfuric acid by biotic and abiotic processes, which have enhanced cave development. The sulfate generally deposits above the water table as a replacement gypsum crust coating limestone walls or as large gypsum crystals. Although the oxidation of sulfide also occurs below the water table, sulfate saturation is not achieved, therefore, sulfate does not precipitate below the water table. In the upper dry levels of the cave, three main types of ancient gypsum deposits occurs: (1) replacement crusts, similar to the presently forming deposits of the active zone, (2) microcrystalline large and thick floor deposits, and (3) euhedral crystals inside mud. The study of the depositional setting and the analysis of sulfur isotopes in the gypsum and groundwater clearly demonstrate that all the sampled gypsum in the cave formed by H2S oxidation above the water table. Some fraction of small sulfur isotopic differences between H2S in the water and gypsum can be explained by isotopic fractionation during abiotic and/or biotic oxidation of H2S.

Hypogenic caves in Provence (France): Specific features and sediments, 2003, Audra Ph, Bigot J. Y, Mocochain L.

Two dry caves from French Provence (Adaouste and Champignons caves) were until now considered as “normal” caves, evolved under meteoric water flow conditions. A new approach gives evidence of a hypogenic origin from deep water uprising under artesian conditions. Specific morphologies and sediments associated with this hydrology are discussed.

On feasibility of condensation corrosion in caves (Comment to the paper: ''Hypogenic caves in Provence (France): Specific features and sediments'' by Ph. Audra, J.Y. Bigot and L. Mocochain), 2003, Dreybrodt, W.

In Fig. 6 of this paper the authors suggest how condensation corrosion could shape ceiling cupolas. Hot water containing high concentration of carbon dioxide rises to a lake filling the lower part of the cave room. Degassing of CO2 creates a CO2-containing atmosphere, which is heated by the warmer water below and becomes saturated with vapor, which condenses to the cooler wall of the cave, dissolves limestone and flows back to the lake.
If this process would continue in time it would be perfect to shape large cupolas. However, it does not because condensation stops when the temperature of the cave walls approaches that of the heated air. The reason is that condensation of water at the cave wall releases heat of condensation of 2.45 kJoule/g. This corresponds to an energy flux of 28 Watt/square-meter if a film of 1 mm depth would condensate to the wall in one day. In addition there is also a flux of heat from the warm air to the cave wall. Since the thermal conductivity of limestone (1.3 Watt/m°K) and its thermal diffusivity (5.6 x 10-7 m2/s) are low this heat cannot be rapidly transported into the bedrock, and consequently the temperature of the cave wall rises. Therefore the amount of condensation is reduced. 

One further comment should be given. There have been attempts to measure the effect of condensation corrosion by suspending gypsum plates freely in the air and determining weight loss after a defined time. For the reasons stated above the heat of condensation and the heat flux from the air raise the temperature of such samples much quicker than that of the cave walls. Reliable measurements can only be performed when such samples are fixed to the cave walls by using a high thermal conductivity glue.

A further suggestion to prove condensed water on cave walls is to take samples and analyse them for Ca-concentration and 13 carbon isotopic ratio. Since CO2 comes from the atmosphere exclusively should be below or close to zero, and Ca-concentration should be about 0.6 mmol/liter, when the pCO2 of the cave atmosphere is atmospheric.

The influence of bedrock-derived acidity in the development of surface and underground karst: Evidence from the Precambrian carbonates of semi-arid northeastern Brazil, 2003, Auler As, Smart Pl,
Very extensive cave systems are developed in Precambrian Una Group carbonates in the Campo Formoso area, eastern Brazil. In contrast, the area is largely devoid of significant surface karst landforms, as would be expected given its semi-arid climate. The caves in the area display many morphological features characteristic of deep-seated hypogenic caves, such as lack of relationship with the surface, ramiform/network pattern, abrupt variations of passage cross-sections and absence of fluvial sediments, but do not show evidence of vertical passages marking the ascending path of acidic water nor present extensive gypsum or acid clay mineral deposits. Hydrochemical analyses of present-day ground water indicate that oxidation of bedrock sulphide is an active process, and sulphuric acid may be the main agent driving carbonate dissolution in the area. A shallow mode of speleogenesis is thus proposed, in which sulphuric acid produced through the oxidation of sulphide beds within the carbonates controls cave initiation and development. Moreover, the geological situation of the area in an ancient stable passive margin precludes the possibility of deep-seated sources of acidity. Under dry climate, due to the absence of recharge, solutional landforms will be largely subdued in the surface. Hypogenic processes, if present, are likely to predominate, producing a landscape characterized by a marked disparity in the comparative degree of development between surface and underground landforms. Rates of karst landform development have traditionally been analysed through a climatic perspective, runoff being the main controlling factor in promoting karst development. This view needs to be reassessed in the light of the growing awareness of the importance of climate-independent processes related to hypogenic sources of acidity.

Formation of Willemite in Hydrothermal Environments, 2003, Brugger J, Mcphail Dc, Wallace M, Waters J,
Willemite (zinc silicate) is the main zinc mineral in some carbonate-hosted ore deposits (e.g., Franklin, New Jersey; Vazante, Brazil; Beltana, South Australia; Kabwe, Zambia). Recent interest in these unconventional zinc deposits has increased because of high zinc grades that exceed 40 wt percent, relatively low environmental impact of ore processing owing to the lack of acid-generating sulfides in the waste, and advances in ore processing technologies. In the past, most metallogenic studies proposed formation of willemite deposits by supergene or hypogene alteration of preexisting sulfide deposits. However, recent data on the Vazante, Beltana, and Kabwe deposits indicate willemite crystallization at temperatures in excess of 150{degrees}C, raising the possibility of primary precipitation from hydrothermal fluids. We use numerical geochemical modeling to examine the formation of willemite under hydrothermal conditions. Activity-activity diagrams reveal that, in the presence of dissolved sulfur and quartz, willemite instead of sphalerite will precipitate under oxidizing (e.g., hematite-stable, sulfate-predominant) and alkaline (pH higher than K feldspar-muscovite-quartz) conditions. Willemite also becomes more stable, relative to sphalerite, at high temperature, and willemite can coexist with magnetite at 300{degrees}C. The stabilities and solubilities of sphalerite, willemite, smithsonite, hydrozincite, and zincite were calculated for wide ranges of temperature (25{degrees}-300{degrees}C), chloride concentration, dissolved sulfur and carbon concentrations, pH, quartz saturation, and oxidation potential. Plots of the solubility of the different minerals as a function of two variables (e.g., temperature and redox state; pH and redox state) allow us to predict the effects of changing chemical conditions, which in turn permits an estimate of the efficiency of particular precipitation processes. Cooling is an effective process for precipitating sphalerite but not willemite, whereas pH increase (e.g., by acidic fluids reacting with carbonates) is effective for precipitating willemite but not sphalerite. Dynamic geochemical models that simulate physicochemical processes are used to understand the formation of the Beltana willemite deposit in the Adelaide geosyncline of South Australia. This small, high grade deposit (850,000 t at 36% Zn) is hosted in dolomite of the Cambrian Ajax Limestone, next to a tectonic contact with the diapiric, halite-bearing clastic sediments of the Callanna Group. The orebody is associated with hematite alteration and is characterized by the total absence of sulfides; willemite is the only zinc ore mineral, and the arsenate hedyphane (Ca2Pb3[AsO4]3Cl) is the main lead mineral. The model results show that willemite will precipitate in response to water-rock interaction and fluid mixing processes at temperatures above 120{degrees}C. The presence of arsenate in the hydrothermal fluid is likely to have been important at Beltana; in arsenate-absent models sulfate is reduced to sulfide by the precipitation of ferrous iron as hematite, resulting in the precipitation of sphalerite and galena. In contrast, in models including arsenate the reduction of sulfate to sulfide is inhibited and willemite is predicted to precipitate

Geology of the Beltana Willemite Deposit, Flinders Ranges, South Australia, 2003, Groves Iain M. , Carman Cris E. , Dunlap W. James,
Beltana is a high-grade hypogene willemite deposit hosted in Lower Cambrian carbonate rocks in the Arrowie basin, northern Flinders Ranges, South Australia. It is situated adjacent to a major growth fault on the basin margin. Ooid grainstone units of the Woodendinna Dolomite and units of Archaeocyathid-rich Wilkawillina Limestone are the main host lithologies. Lead minerals in subeconomic quantities are also present in karstic collapse breccias surrounding the willemite orebodies. Mineralization is structurally controlled and associated with brecciation and extensive hematite-rich hydrothermal zincian dolomitization. Ore minerals include willemite and coronadite with lesser mimetite, hedyphane, and smithsonite. Late-stage gangue minerals include manganocalcite, dolomite, and minor quartz. The texture of willemite is heterogeneous, resulting from various depositional mechanisms such as partial to massive replacement of the carbonate host rock, internal sedimentation, fracture fill, brecciation, and vein fill. On the periphery of the deposit, smithsonite formed by weathering of willemite. Beltana is centered on a karstic collapse breccia that extends at least 100 m vertically, formed in part through corrosion by acidic ore solutions. The geochemical signature of the orebody includes high levels of Zn, Pb, Cd, As, and Mn. Notably, silver is absent from the deposit and sulfur concentrations are low (<20 ppm). Fluid inclusion studies yield a low minimum temperature range of ore deposition between 50{degrees} and 170{degrees}C. K-Ar dating of coronadite associated with the willemite orebody indicates an age of formation of ~ 435 {} 5 Ma. Premining resources of willemite ore were 850,000 t at 36 percent Zn, and an associated body of subeconomic lead contained more than 800,000 t at 8.9 percent Pb, 3.9 percent Zn and 1 percent As. The deposit has some similarities with Mississippi Valley-type deposits but differs in ore and alteration mineral assemblages

Classification, Genesis, and Exploration Guides for Nonsulfide Zinc Deposits, 2003, Hitzman Murray W. , Reynolds Neal A. , Sangster D. F. , Allen Cameron R. , Carman Cris E. ,
Nonsulfide zinc deposits, popularly but incorrectly termed 'zinc oxide' deposits, are becoming attractive exploration targets owing to new developments in hydrometallurgy. They are divided into two major geologic types--supergene and hypogene deposits. Supergene deposits are the most common type of nonsulfide zinc deposit and are distributed worldwide. The vast majority occur in carbonate host rocks owing to the high reactivity of carbonate minerals with the acidic, oxidized, zinc-rich fluids derived from the oxidative destruction of sphalerite-bearing sulfide bodies. Formation of these deposits depends upon the size and mineralogy of the preexisting zinc occurrence, vertical displacement of the water table, rate of water table descent through tectonic uplift and/or arid climatic conditions, wall-rock fracture density, and a suitable neutralizing trap site. Weathering of Mississippi Valley-type and high-temperature carbonate replacement-type zinc deposits may generate significant supergene nonsulfide zinc deposits, but the weathering of pyrite-rich, sedimentary exhalative, and volcanogenic massive sulfide deposits is much less likely to form economic supergene zinc deposits. Three subtypes of supergene nonsulfide zinc deposits are recognized--direct replacement, wall-rock replacement, and residual and karst-fill deposits. Hypogene nonsulfide zinc deposits are more poorly known owing to the paucity of examples; however, two major subtypes are recognized: structurally controlled, replacement bodies and manganese-rich, exhalative(?) stratiform bodies. The structurally controlled bodies contain willemite and variable amounts of sphalerite, are hematitic, and are generally associated with hydrothermal dolomitization. Stratiform, manganese-rich, nonsulfide zinc deposits appear to be end members of a spectrum of deposits that include base metal-poor stratiform manganese deposits and sulfide-dominant Broken Hill-type deposits. Hypogene nonsulfide zinc deposits appear to have formed owing to the mixing of a reduced, low- to moderate-temperature (80{degrees}-200{degrees}C), zinc-rich, sulfur-poor fluid with an oxidized, sulfur-poor fluid

Sistema Zacaton: Identifying the connection between volcanic activity and hypogenic karst in a hydrothermal phreatic cave system, 2003, Gary M. O. , Sharp J. M. , Havens R. S. , Stone W. C.

Discrimination of effective from ineffective porosity in heterogeneous Cretaceous carbonates, Al Ghubar field, Oman , 2003, Smith L. B. , Eberli G. P. , Masaferro J. L. , Aldhahab S.

The Natih E heavy-oil reservoir (21j API) atAl Ghubar field, Oman has produced less than 5% of the calculated oil in place. Porosity logs used to calculate reserves show high porosity throughout the reservoir, but further analysis of the only continuous core taken from the field indicates that much of the porosity is ineffective. There are four heavily oil-stained, high-permeability skeletalpelletal grainstone units with interparticle porosity in the core that probably contributed most of the production. The four permeable grainstone units occur at the top of small-scale accommodation cycles that have wackestone and packstone bases. These grainstones make up about 20% of the total thickness of the porous Natih E reservoir. The other 80% is composed of packstone and wackestone with ineffective microporosity, interparticle porosity in burrows, and isolated moldic and intraskeletal porosity. The small-scale reservoirbearing cycles can be correlated across the field using the separation between the medium and deep induction curves as a guide. Resistivity logs are the most reliable tool to distinguish effective from ineffective porosity. Most high-permeability grainstone units have deep induction values more than 100 ohmmand separation of more than 10 ohm m between the medium and deep induction curves. The ineffective intervals with microporosity, burrow porosity, and moldic porosity have lower resistivity and little separation between the medium and deep induction curves 

Geophysical evidence for karst formation associated with offshore groundwater transport: An example from North Carolina, 2003, Evans Rob L. , Lizarralde Dan

Marine geophysical data from Long Bay, North Carolina, involving a novel combination of electromagnetic and high-resolution Chirp seismics, show evidence of submarine karst formation associated with what has been inferred to be a site of high-flux submarine groundwater discharge (SGD) a substantial distance offshore. Recently observed temperature and chemical signals from wells in this area provide the basis for the interpretation of the high-flux SGD here, and they also suggest a terrestrial source for the groundwater and thus a potentially important route for nutrient transport to the oceans. Our data indicate that karstification is localized to the high-flux zone, and we suggest that mixing of the chemically distinct (but saline) groundwater with seawater has resulted in the karstification. As karstification increases permeability and flux, a positive feedback would tend to progressively enhance submarine groundwater discharge. Our data reveal a significant local anomaly in apparent porosity: a dense block that may have initiated the local focusing of groundwater flow. Conditions favorable to the formation of similar locally punctuated sites of high-flux SGD are likely to exist along the mid to inner shelf of the southeastern United States, where carbonate aquifers are prevalent

A hypogenic cave formed by ''connate'' water from the Craven Basin? [Arthur's Cave, Bowland], 2004, Hunt Barry M.

Rates of condensation corrosion in speleothems of semi-arid northeastern Brazil, 2004, Auler A. S. , Smart P. L.

Condensation corrosion is a little studied, but important dissolutional process that occurs within caves in many karst settings around the world (for a review see Dublyansky and Dublyansky, 2000). Condensation corrosion occurs when air equilibrates with the cave atmosphere, becomes acidic and dissolves the bedrock and speleothems. It is a later vadose process that apparently depends on air circulation patterns, number of entrances and general configuration (vertical range, presence of ponded water, passage shape, etc) of the cave. Both bedrock and speleothems can be affected by the process, resulting in weathered outer surfaces. Condensation corrosion in speleogenesis has been regarded as responsible for dissolutional modification during later stages of cave development of coastal (Tarhule-Lips and Ford, 1998) and hypogenic caves (Hill, 1987; Palmer and Palmer, 2000).
Condensation corrosion is a little studied, but important dissolutional process that occurs within caves in many karst settings around the world (for a review see Dublyansky and Dublyansky, 2000). Condensation corrosion occurs when air equilibrates with the cave atmosphere, becomes acidic and dissolves the bedrock and speleothems. It is a later vadose process that apparently depends on air circulation patterns, number of entrances and general configuration (vertical range, presence of ponded water, passage shape, etc) of the cave. Both bedrock and speleothems can be affected by the process, resulting in weathered outer surfaces. Condensation corrosion in speleogenesis has been regarded as responsible for dissolutional modification during later stages of cave development of coastal (Tarhule-Lips and Ford, 1998) and hypogenic caves (Hill, 1987; Palmer and Palmer, 2000).
The Campo Formoso Karst area of northeastern Brazil holds very extensive cave systems, such as Southern Hemisphere’s longest cave, the 97 km long Toca da Boa Vista. These caves show remarkable features of condensation corrosion such as cupolas, weathered cave walls yielding dolomitic sand, “air scallops” and corroded speleothems. Weathering rinds up to 5 cm thick occur in both dolomite bedrock and speleothem surfaces. Unlike the dolomite, speleothems usually do not disintegrate but change to a milky white opaque porous calcite that is in marked contrast with the fresh crystalline calcite. The area is presently under semi-arid climate and the cave atmosphere is characterised by high internal temperatures (2729 °C) and low relative humidity (mean of 73% for sites away from entrances).
Despite being such a widespread process, rates of condensation corrosion have so far been reported only from caves in the coastal area of the Caribbean (Tarhule-Lips and Ford, 1998). In this study, rates of condensation corrosion in speleothems were derived by determining thickness of weathering rind and age of last unaltered calcite. These rates represent minimum rates because speleothem growth ceased later than age obtained, and also condensation corrosion may not be continuous in time. Due to variable thickness of weathering layer (usually thicker at the top and thinner at sides of stalagmites), maximum and minimum thickness were obtained for each sample. Dating was performed through the alpha spectrometric U-series method in the first unaltered calcite layer beyond the weathering rim. 
The rates obtained vary over two orders of magnitude. They appear to be highly site specific, and are probably heavily dependent on the local atmospheric conditions, although more sampling is needed to confirm this relationship. The data shows that rates are dependent primarily on thickness measured, as range of ages is quite small. Tarhule-Lips and Ford (1998), in the very different littoral caves of the Caribbean, have estimated condensation corrosion rates based on experiments using gypsum tablets. Their reported mean value of 24 mm/ka, much higher than observed in the Campo Formoso caves, suggest that the process may be episodic in the area, not occurring during speleothem growth phases associated with wetter periods.
Although the rates reported by Tarhule-Lips and Ford (1998) indicate that condensation corrosion may actually enlarge cave passages in the normal (10 4 – 10 6 ka) time range of speleogenesis, in the Campo Formoso caves the process appears to play a minor speleogenetic role, being responsible for later modification of cave walls and speleothems.

Speleogenesis: Deep-Seated and Confined Settings, 2004, Klimchouk A.

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