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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 debris karren is these are pinnacles that form in limestones with a thin sheet structure that soon fall into smaller fragments [3]. see also pinnacles.?

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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 sulfate (Keyword) returned 118 results for the whole karstbase:
Showing 106 to 118 of 118
CAVES AND KARST-LIKE FEATURES IN PROTEROZOIC GNEISS AND CAMBRIAN GRANITE, SOUTHERN AND CENTRAL SRI LANKA: AN INTRODUCTION, 2013, Osborne R. A. L. , Weliange W. S. , Jayasingha Pathmakumara, Dandeniya A. S. , Algiriya A. K. Prageeth P. & Pogson Ross E.

There has been little study of the geology and geomorphology of the caves and karst­like features developed in the Proterozoic gneiss and Cambrian granite of Sri Lanka. This lack of study is surprising given that caves and rockshelters in these rocks contain significant archaeological and cultural sites. Caves and karren, both mimicking those developed in carbonate rocks, have formed both in gneiss, which is the dominant rock type of the Proterozoic crust of the island and in granite. In addition to overhangs, boulder caves, soil pipes and tectonic caves, tunnel caves, arch caves and block breakdown caves of significant size are developed in siliceous rocks in Sri Lanka. while metamorphosed dolomites are interfoliated within the gneissic suite, simple removal of carbonate by solution from within the surrounding rock cannot account for all or most of the speleogenesis observed. while spalling and breakdown are responsible for cave enlargement, cave initiation is probably due to either phreatic solution of silicates and/or phantom rock processes. Speleothems and cave minerals including silicates, phosphates, gypsum, carbonates and niter are found in the caves. Active silicate speleothems are not restricted to joints and fissures and suggest that solution of silicates is currently occurring within the body of the rock in the vadose zone. while guano is the likely source of the phosphate, sulfate and nitrate, the source of the calcium in the carbonates remains unclear. Caves in the intrusive and metamorphic rocks of Sri Lanka are enigmatic. They are unexpectedly similar in appearance to their carbonate karst counterparts. Continuing research will allow them to hold a mirror to our understanding of speleogenesis, mineralization and sedimentation in carbonate karst caves.


HOW DEEP IS HYPOGENE? GYPSUM CAVES IN THE SOUTH HARZ, 2014, Kempe, S.

Germany currently features 20 caves in sulfate rocks (gypsum and anhydrite) longer than 200 m. Most of them occur either in the Werra-Anhydrite or in the Hauptanhydrite of the evaporitic Zechstein series (Upper Permian). One occurs in the Jurassic Münder Mergel and two in the Triassic Grundgips. The longest, the Wimmelburger Schlotten, is 2.8 km long with a floor area of 24,000 m2. All caves, except four, occur in the South Harz, where the Zechstein outcrop fringes the uplifted and tilted Variscian Harz. These caves can be divided into three general classes: (i) epigenic caves with lateral, turbulent water flow, and (ii) shallow or (iii) deep phreatic caves with slow convective density-driven dissolution. The latter were discovered during historic copper-shale mining and called “Schlotten” by the miners; most of them are not accessible any more. Shallow phreatic caves occur in several areas, most notably in the Nature Preserve of the Hainholz/Beierstein at Düna/Osterode/Lower Saxony. Here, we sampled all water bodies in May 1973 and monitored 31 stations between Nov. 23rd, 1974, and April 24th, 1976, with a total 933 samples, allowing us to characterize the provenance of these waters. These monitoring results were published only partially (PCO2 data, see Kempe, 1992). Here, I use the data set to show that the Jettenhöhle (the largest cave in the Hainholz) has been created by upward moving, carbonate-bearing, groundwater of high PCO2. Even though the cave has now only small cave ponds and essentially is a dry cave above the ground water level, it is a hypogene cave because of the upward movement “of the cave-forming agent” (sensu Klimchouk, 2012). Likewise, the Schlotten are created by water rising from the underlying carbonate aquifer, but under a deep phreatic setting


HYPOGENE LIMESTONE CAVES IN GERMANY: GEOCHEMICAL BACKGROUND AND REGIONALITY, 2014, Kempe, S.

Germany exhibits a very diverse geological history. Thus, a large number of stratigraphically, petrographically and tectonically different carbonate and sulfate rocks exist that have been subject to karstification. Here, I discuss first the possible “agents” (sensu Klimchouk) of hypogene karstification. Three principally different processes are identified: water rising because of buoyancy (either thermally or concentration induced), in-situ oxidation of siderite, or rising gases (CO2, CH4 or H2S). Next, a rough overview of German caves and karst is presented. If applying the most pertinent epigene versus hypogene morphological characteristics, it becomes evident that hypogene caves occur in many different areas, often side-by-side with clearly epigene caves. For many areas, the agents of hypogene speleogenesis must remain unclear. This applies for most caves in the Paleozoic limestones of the Rhenish Schist Massif. Only the Iberg/Harz caves seem to be a clear case, with the world-wide highest concentrations of siderite weathering-induced caves occur. The large cavities discovered recently in the Blauhöhlen System and some of the deep pit caves in the Swabian Alb may have their explanation in volcanic CO2, having emanated from some of the 355 pipes of the Swabian volcanic field. Most striking is the high concentration of hypogene caves in the Franconian Alb. Many of them occur in a small area while other areas are devoid of larger caves. Here the tectonic situation suggests that fractures could have taped reservoirs of either sulfide or methane from below. The finding of goethitic crusts in the Bismarckgrotte may indicate that rising anaerobic gases could have been involved


HYPOGENE VS EPIGENE CAVES: THE SULFUR AND OXYGEN ISOTOPE FINGERPRINT, 2014, Onac, B. P.

The classical epigene speleogenetic model in which CO2 is considered the main source of acidity has been challenged over the last three decades by observations that revealed cave passages unrelated to groundwater drainage routes and surface topography. Most of these passages show unusual morphologies, such are cupolas, floor feeders (i.e., inlets for deep-seated fluids), and huge irregular-shaped rooms that terminate abruptly, and often a rich and diverse mineral association. A hypogenetic speleogenetic pathway was proposed for this group of caves.
The presence of abundant gypsum deposits in caves with one or more of the passage morphologies listed above, have prompted scientists to suggest a new theory (i.e., sulfuric acid speleogenesis, SAS) of cave development. In the hypogenic SAS model, the source of acidity is the sulfuric acid produced by oxidation of H2S (originating from sulfate reduction or petroleum reservoirs) near or at the water table, where it dissolves the limestone bedrock and precipitates extensive gypsum deposits. SAS is now thoroughly documented from numerous caves around the world, with the best examples coming from the Guadalupe Mountains (NM), Frasassi caves (Italy), selected caves in France, Cueva de Villa Luz (Mexico), and Cerna Valley (SW Romania).
To date, discrimination between epigene and hypogene speleogenetic pathways is made using cave morphology criteria, exotic mineral assemblages, and the predominantly negative δ34S values for the cave sulfates. This presentation highlights the role sulfur and oxygen stable isotope analyses have in discriminating between epigene and hypogene caves.
Based on a number of case studies in caves of the Cerna Valley (Romania), we found that relatively S-depleted isotopic composition of cave minerals alone does not provide enough information to clearly distinguish SAS from other complex speleogenetic pathways. In fact, δ34S values of SAS by-products depend not only on the source of the S, but also on the completeness of S redox reactions. Therefore, similar studies to this are needed to precisely diagnose SAS and to provide information on the S cycle in a given karst system.
Integrating cave mineralogy, passage morphology, and geochemical studies may shed light on the interpretation of polygenetic caves, offering clues to processes, mechanisms, and parameters involved in their genesis (sulfate-dominated).


SPELEOGENESIS BY THE SULFIDIC SPRINGS AT NORTHERN SIERRA DE CHIAPAS, MEXICO, BASED ON THEIR WATER CHEMISTRY, 2014, Rosaleslagarde L. , Boston P. J.

Conspicuous brackish sulfidic springs have been described at the northern Sierra the Chiapas, Mexico. These springs are produced by a mixture between regional and local groundwater flow paths. The regional groundwater has an average Total Dissolved Ions of 3081 mg/L so it has a brackish composition. This brackish water is saturated with respect to calcite and dolomite but undersaturated with respect to gypsum, anhydrite and halite. The mass balance and the discharge rate are used to quantify the mass and volume of minerals that are dissolved by the brackish spring water following Appelo and Postma (1993). This quantification will allow comparing the various speleogenetic mechanisms in the area. This is considering the composition of the spring water is relatively constant over time, as it is suggested by periodic measurements at the Cueva de Villa Luz springs during the last 10 years.
Sulfur isotopes in the water are consistent with anhydrite dissolution as the main source of the sulfate to the brackish spring water. Thus, the average 6 mol/L of sulfate in the brackish springs are produced by dissolution of 6 mol of anhydrite after subtracting the sulfate that could result from evapotranspiration of rainwater. Each liter of brackish water dissolved an average of 882 mg of anhydrite, which are equivalent to dissolving 0.36 cm3 of this mineral considering a density of 2.981 g/cm3. Additionally, using the average brackish water discharge rate of 144 L/s, an average of 57 g of anhydrite are being dissolved each second per every liter of brackish water. This is a minimal value because some of the sulfate in the water is used by sulfate-reducing bacteria in the subsurface to produce the hydrogen sulfide in the spring water. The anhydrite subject to dissolution is found interbedded in the Cretaceous carbonates, either from the subsurface at 4,000 m below sea level to the carbonate outcrops.
Similarly, we can calculate the volume of halite that is being dissolved by the brackish springs, considering chloride is a conservative element and subtracting the chloride concentration from the rainwater from that of the spring water following Appelo & Postma (1993). The 22 mol/L of chloride in the brackish water can result from dissolution in the subsurface of 22 moles or 1.3 g of halite per liter of brackish water. This mass of halite dissolved is equal to 0.59 cm3 considering a density of 2.168 g/cm3. Alternatively, 118 g of halite are dissolved per second per each liter of brackish water if we use the average discharge rate of 144 L/s.
Even when the brackish springs are oversaturated with respect to calcite and dolomite, their dissolution is still possible due to the common ion-effect of calcium after anhydrite dissolution and by mixing of waters with different compositions. A range of 10 to 80 % of brackish water from the regional aquifers mixes with fresh water from the local aquifer based on their water chemistry. Additionally, sulfuric acid speleogenesis occurs due to the oxidation of hydrogen sulfide to sulfuric acid.
Finally, the increase in the chloride concentration of the fresh water springs with respect to the concentration in rainwater was used to estimate that from the 4000 mm/y of annual precipitation, only 4%, 158 to 182 mm/y, recharge the aquifers. This low percentage is slightly higher than the 3.3% recharge in marls, marly limestone, silts and clays (Sanz et al., 2011), probably because of the relatively small area of carbonate outcrops over the entire region and the lack of recharge in altitudes higher than 1500 m above sea level.
Sulfuric acid is the most obvious speleogenetic mechanism occurring in the caves of the northern Sierra de Chiapas, Mexico due to the high hydrogen sulfide concentration in the spring water. In addition, the location of the springs at a zone of regional and local discharge where waters from different composition converge and mix, and the amount of mixing calculated suggests mixing is also an important speleogenetic mechanism. However, the depth and the time constrains at which these two hypogenic mechanisms occur is still unknown. The relatively low rainwater recharge rate suggests epigenesis is limited. Most likely, the porosity created by dissolution of anhydrite and halite in the subsurface is occluded by the precipitation of calcite. Chemical modeling and petrography will help to elucidate the order of the reactions occurring in the subsurface.


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


The fate of CO2 derived from thermochemical sulfate reduction (TSR) and effect of TSR on carbonate porosity and permeability, Sichuan Basin, China, 2015, Hao Fang, Zhang Xuefeng, Wang Cunwu, Li Pingping, Guo Tonglou, Zou Huayao, Zhu Yangming, Liu Jianzhang, Cai Zhongxian

This article discusses the role ofmethane in thermochemical sulfate reduction (TSR), the fate of TSR-derived CO2 and the effect of TSR on reservoir porosity and permeability, and the causes of the anomalously high porosity and permeability in the Lower Triassic soured carbonate gas reservoirs in the northeast Sichuan Basin, southwest China. The Lower Triassic carbonate reservoirs were buried to a depth of about 7000 m and experienced maximum temperatures up to 220 °C before having been uplifted to the present-day depths of 4800 to 5500 m, but they still possess porosities up to 28.9% and permeabilities up to 3360 md. The present-day dry gas reservoirs evolved from a paleo-oil accumulation and experienced varying degrees of TSR alteration as evidenced from the abundant sulfur-rich solid bitumens and varying H2S and CO2 concentrations. TSR occurred mainly within the oil and condensate/wet gas windows, with liquid hydrocarbons and wet hydrocarbon gases acting as the dominant reducing agents responsible for sulfate reduction, sulfur-rich solid bitumen and H2S generation, and calcite precipitation. Methane-dominated TSR was a rather late event and had played a less significant role in altering the reservoirs. Intensive H2S and CO2 generation during TSR resulted in calcite cementation rather than carbonate dissolution, which implies that the amount of water generated during TSR was volumetrically insignificant. 13C-depleted CO2 derived from hydrocarbon oxidation preferentially reacted with Ca2+ to form isotopically light calcite cements, and the remaining CO2 re-equilibrated with the 13C-enriched water–rock systems with its δ13C rapidly approaching the values for the host rocks, which accounted for the observed heavy and relatively constant CO2 δ13C values. The carbonate reservoirs suffered from differential porosity loss by TSR-involved solid bitumen generation and TSR-induced calcite and pyrite precipitation. Intensive TSR significantly reduced the porosity and permeability of the intervals expected to have relatively high sulfate contents (the evaporative-platform dolostones and the platform-margin shoal dolostones immediately underlying the evaporative facies). Early oil charge and limited intensity of TSR alteration, together with very low phyllosilicate content and early dolomitization, accounted for the preservation of anomalously high porosities in the reservoirs above the paleo-oil/water contact. A closed system seems to have played a special role in preserving the high porosity in the gas zone reservoirs below the paleo-oil/water contact. The closed system, which is unfavorable for deep burial carbonate dissolution and secondary porosity generation, was favorable for the preservation of early-formed porosity in deeply buried carbonates. Especially sucrosic and vuggy dolostones have a high potential to preserve such porosity.


Hypogene Sulfuric Acid Speleogenesis and rare sulfate minerals in Baume Galini`ere Cave (Alpes-de-Haute-Provence, France). Record of uplift, correlative cover retreat and valley dissection, 2015, Audra Philippe, Gґazquez Fernando, Rull Fernando, Bigot Jeanyves, Camus Hubert

The oxidation of hydrocarbons and sulfide sources (H2S, pyrite) produces sulfuric acid that strongly reacts with bedrock, causing limestone dissolution and complex interactions with other minerals from the bedrock or from cave fillings, mainly clays. This type of cave development, known as Sulfuric Acid Speleogenesis (SAS), is a subcategory of hypogene speleogenesis, where aggressive water rises from depth. It also produces uncommon minerals, mainly sulfates, the typical byproducts of SAS. Baume Galinière is located in Southern France, in the Vaucluse spring watershed. This small maze cave displays characteristic SAS features such as corrosion notches, calcite geodes, iron crusts, and various sulfate minerals. Sulfur isotopes of SAS byproducts (jarosite and gypsum) clearly show they derive from pyrite oxidation. Using XRD and micro-Raman spectroscopy, thirteen minerals were identified, including elemental sulfur, calcite, quartz, pyrite, goethite, gypsum, fibroferrite, plus all of the six members of the jarosite subgroup (jarosite, argentojarosite, ammoniojarosite, hydroniumjarosite, natrojarosite, plumbojarosite). The Baume Galinière deposits are the first documented cave occurrence of argentojarosite and the second known occurrence of plumbojarosite, hydronium jarosite, ammoniojarosite, and fibroferrite. In the Vaucluse watershed, there were numerous upwellings of deep water along major faults, located at the contact of the karstic aquifer and the overlying impervious covers. The mixing of deep and meteoric waters at shallow depths caused pyrite depositions in numerous caves, including Baume Galinière. Sulfuric acid speleogenesis occurred later after base-level drop, when the cave was under shallow phreatic conditions then in the vadose zone, with oxidation of pyrites generating sulfuric acid. Attenuated oxidation is still occurring through condensation of moisture from incoming air. Baume Galinière Cave records the position of the semi-impervious paleo-cover and documents its retreat in relationship to valley incision caused by uplift and tilting of the Vaucluse block during the Neogene.


Hypogene Sulfuric Acid Speleogenesis and rare sulfate minerals in Baume Galinière Cave (Alpes-de-Haute-Provence, France). Record .., 2015, Audra P. , Gázquez F. , Rull F. , Bigot J. Y. , Camus H.

The oxidation of hydrocarbons and sulfide sources (H2S, pyrite) produces sulfuric acid that strongly reacts with bedrock, causing limestone dissolution and complex interactions with other minerals from the bedrock or from cave fillings, mainly clays. This type of cave development, known as Sulfuric Acid Speleogenesis (SAS), is a subcategory of hypogene speleogenesis, where aggressive water rises from depth. It also produces uncommon minerals, mainly sulfates, the typical byproducts of SAS. Baume Galinière is located in Southern France, in the Vaucluse spring watershed. This small maze cave displays characteristic SAS features such as corrosion notches, calcite geodes, iron crusts, and various sulfate minerals. Sulfur isotopes of SAS byproducts (jarosite and gypsum) clearly show they derive from pyrite oxidation. Using XRD and micro-Raman spectroscopy, thirteen minerals were identified, including elemental sulfur, calcite, quartz, pyrite, goethite, gypsum, and fibroferrite, plus all of the six members of the jarosite subgroup (jarosite, argentojarosite, ammoniojarosite, hydroniumjarosite, natrojarosite, plumbojarosite). The Baume Galinière deposits are the first documented cave occurrence of argentojarosite and the second known occurrence of plumbojarosite, hydronium jarosite, ammoniojarosite, and fibroferrite. In the Vaucluse watershed, there were numerous upwellings of deep water along major faults, located at the contact of the karstic aquifer and the overlying impervious covers. The mixing of deep and meteoric waters at shallow depths caused pyrite depositions in numerous caves, including Baume Galinière. Sulfuric Acid Speleogenesis occurred later after base-level drop, when the cave was under shallow phreatic conditions then in the vadose zone, with oxidation of pyrites generating sulfuric acid. Attenuated oxidation is still occurring through condensation of moisture from incoming air. Baume Galinière Cave records the position of the semi-impervious paleo-cover and documents its retreat in relationship to valley incision caused by uplift and tilting of the Vaucluse block during the Neogene.


Evaporite karst in three interior layered deposits in Iani Chaos, Mars, 2015,

This paper describe the karst landforms observed in three interior layered deposits located in Iani Chaos, a large depression located in the equatorial region of Mars, characterised by spectral signatures of monohydrated and polyhydrated sulfate such as kieserite and gypsum. A morphological and morphometric survey of the ILD surface morphologies through an integrated analysis of the available Mars Reconnaissance Orbiter (MRO) High Resolution Imaging Science Experiment (HiRISE) highlighted the presence of depressions of various shapes and sizes. These Martian landforms interpreted as doline of polygenetic origin resemble similarly karst landforms that can be observed both in different karst terrains on Earth and in other regions of Mars. The karst landforms observed suggest a climatic change and the presence of liquid water, probably due to ice melting, in the late Amazonian age.


Influence of the f low rate on dissolution and precipitation features during percolation of CO 2 - rich sulfate solutions through fractured limestone samples , 2015,

Calcited issolution and  gypsum precipitation is expected to occur  when injecting CO2  in  a limestone reservoir with sulfate - rich resident brine. If the reservoir is fractured, These reactions will take place mainly in the fractures, which serve as preferential paths for fluid  flow. As a consequence, the geometry of the fractures will vary leading to changes  in their hydraulic and transport properties. In this study, a set of percolation  experiments  which  consisted of injecting CO 2 - rich solutions through fractured  limestone  cores were performed under P  =  150 bar and  T  =  60  ºC .  Flow rate s ranging from 0.2 to 60 mL/ h and sulfate - rich and sulfate - free solutions  were used. Variation in fracture volume induced by calcite dissolution and  gypsum precipitation was measured by X - ray computed microtomography  (XCMT) and aqueous chemistry. An increase in flow rate led to  an increase in  volume of dissolved limestone per unit of  time , which indicated that the calcite dissolution rate in the fracture  was transport  controlled. Moreover, the dissolution pattern varied from face dissolution to wormhole formation  and uniform dissolution by increasing the flow rate (i.e.,  Pefrom 1 to 346 ). Fracture permeability always increased and depended on the type of dissolution pattern.


Sulfuric acid speleogenesis (SAS) close to the water table: Examples from southern France, Austria, and Sicily, 2015,

Caves formed by rising sulfuric waters have been described from all over the world in a wide variety of climate  settings, from arid regions to mid-latitude and alpine areas. H2S is generally formed at depth by reduction of  sulfates in the presence of hydrocarbons and is transported in solution through the deep aquifers. In tectonically  disturbed areas major fractures eventually allow these H2S-bearing fluids to rise to the surface where oxidation  processes can become active producing sulfuric acid. This extremely strong acid reacts with the carbonate  bedrock creating caves, some of which are among the largest and most spectacular in the world. Production of  sulfuric acid mostly occurs at or close to the water table but also in subaerial conditions in moisture films and  droplets in the cave environment. These caves are generated at or immediately above the water table, where  condensation–corrosion processes are dominant, creating a set of characteristic meso- and micromorphologies.  Due to their close connection to the base level, these caves can also precisely record past hydrological and  geomorphological settings. Certain authigenic cave minerals, produced during the sulfuric acid speleogenesis  (SAS) phase, allow determination of the exact timing of speleogenesis. This paper deals with the morphological,  geochemical and mineralogical description of four very typical sulfuric acid water table caves in Europe: the  Grotte du Chat in the southern French Alps, the Acqua Fitusa Cave in Sicily (Italy), and the Bad Deutsch Altenburg  and Kraushöhle caves in Austria


Chemistry and Karst, 2015, White, William B.

The processes of initiation and development of characteris­tic surface karst landforms and underground caves are nearly all chemical processes. This paper reviews the advances in understanding of karst chemistry over the past 60 years. The equilibrium chemistry of carbonate and sulfate dissolution and deposition is well established with accurate values for the necessary constants. The equations for bulk kinetics are known well enough for accurate modeling of speleogenetic processes but much is being learned about atomic scale mechanisms. The chemistry of karst waters, expressed as parameters such as total dissolved carbonates, saturation index, and equilibrium carbon dioxide pressure are useful tools for probing the internal char­acteristics of karst aquifers. Continuous records of chemical parameters (chemographs) taken from springs and other karst waters mapped onto discharge hydrographs reveal details of the internal flow system. The chemistry of speleothem deposi­tion is well understood at the level of bulk processes but much has been learned of the surface chemistry on an atomic scale by use of the atomic force microscope. Least well understood is the chemistry of hypogenetic karst. The main chemical reac­tions are known but equilibrium modeling could be improved and reaction kinetics are largely unknown.


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