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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 flash flood is a relatively short but very intense flood [16].?

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 hydrogen (Keyword) returned 66 results for the whole karstbase:
Showing 1 to 15 of 66
Algological studies in the cave of Matyas Mount, Budapest, Hungary., 1966,
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Hajdu Lajos.
Experiments were designed to test the ability of the aphotic speleoenvironment to support algal growth. The first series contained gelatin cultures of Scenedesmus placed in the cave at different localities in order to establish whether or not the microhabitats have any particular effect on the multiplication of the algae. No differences were found in the cultures after a three month incubation period in the cave, which could be traced to influences of microenvironmental conditions. Chlorella cultures in sterile Knop's solution showed measurable growth in the cave whereas if the cultures were installed into sterilized cave water or were shielded by lead against possible radiation effects, no appreciable growth occurred. The presence or absence of magnetic field did not noticeably influence algal development. The experiments seemed to indicate that the algae tested are able to utilize soma kind of radiation in the complete darkness of the cava since, in the absence of organic material, appreciable amounts of molecular hydrogen or symbiotic activity, with iron bacteria, considerable growth occurred in a simple, strictly inorganic medium, whereas the cave waters seam to be deficient in some kind of inorganic salt required for algal nutrition. An investigation of algae living in the cave led to the determination of ten different taxa, the majority of which were Cyanophytes. Besides them, however, the cave may contain a more diversified algal population.

Identification of the origin of oreforming solutions by the use of stable isotopes, 1977,
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Sheppard S. M. F. ,
SynopsisThe four major different types of water -- magmatic, metamorphic, sea water and/or connate, and meteoric water -- have characteristic hydrogen (D/H) and oxygen (18O/16O) isotope ratios. Applied to the analysis of isotopic data on hydrothermal minerals, fluid inclusions and waters from active geothermal systems, these ratios indicate that waters of several origins are involved with ore deposition in the volcanic and epizonal intrusive environment. Water of a single origin dominates main-stage mineralization in some deposits: magmatic -- Casapalca, Peru (Ag-Pb-Zn-Cu); meteoric -- Butte, Montana (Cu-Zn-Mn), epithermal deposits, e.g. Goldfield, Tonopah, Nevada (Ag-Au), Pachuca, Mexico (Ag-Au), San Juan Mountains District, Colorado (Ag-Au-Pb-Zn); sea water -- Troodos, Cyprus (Fe-Cu), Kuroko, Japan (Fe-Cu-Pb-Zn). Solutions of more than one origin are important in certain deposits (magmatic and meteoric -- porphyry copper and molybdenum deposits) and are present in many. In the porphyry Cu-Mo deposits the initial major ore transportation and alteration processes (K-feldspar-biotite alteration) are magmatic-hydrothermal events that occur at 750-500{degrees}C. These fluids are typically highly saline Na-K-Ca-Cl-rich brines (more than 15 wt % equivalent NaCl). The convecting meteoric-hydrothermal system that develops in the surrounding country rocks with relatively low integrated water/rock ratios (less than 0.5 atom % oxygen) subsequently collapses in on a waning magmatic-hydrothermal system at about 350-200{degrees}C. These fluids generally have moderate to low salinities (less than 15 wt % equivalent NaCl). Differences among these deposits are probably in part related to variations in the relative importance of the meteoric-hydrothermal versus the magmatic-hydrothermal events. The sulphur comes from the intrusion and possibly also from the country rocks. Deposits in which meteoric or sea water is the dominant constituent of the hydrothermal fluids come from epizonal intrusive and sub-oceanic environments where the volcanic country rocks are fractured or well jointed and highly permeable. Integrated water/rock ratios are typically high, with minimum values of 0.5 or higher (atom % oxygen) -- the magmatic water contribution is often drowned out'. Salinities are low to very low (less than 10 wt % equivalent NaCl), and temperatures are usually in the range 350-150{degrees}C. The intrusion supplies the energy to drive the large-scale convective circulation system. The sulphur comes from the intrusion, the country rocks and/or the sea water. Argillic alteration, which occurs to depths of several hundred metres, generated during supergene weathering in many of these deposits is isotopically distinguishable from hydrothermal clays

The isotopes of hydrogen and oxygen in precipitation, 1980,
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Gat J. R.

Relationships between the internal and external evolution of the Monte Cucco Karst Complex. Umbria, Central Italy., 1987,
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Guzzetti Fausto
The relationships between the internal and external evolution of the Mt. Cucco karst complex are studied. A classic set of equations, involving the oxidation of hydrogen sulphide, originated at depth in an evaporitic formation, is used to explain the presence of massive gypsum deposits in the Mt. Cucco and the Faggeto Tondo caves. The distribution and the morphology of more than 30 caves in the system, the presence of gypsum, always located along faults, and the presence of broken stalactites and columns, suggest that the evolution of the karst system has been controlled by tectonic movements. Relationships between the development of the caves and the geomorphic evolution of the area are proposed.

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Ellins Kk,
The hydrology of a small karst drainage basin in Jamaica, the Martha Brae River basin, was examined using stable isotopes. Variations in the isotopic composition of the groundwaters sampled and their positions relative to the local meteoric water line on a delta-D/delta-O-18 diagram permitted the identification of two distinct groundwater types. The isotopic data also provided evidence that the most productive portion of the aquifer is divided by a major fault, which impedes groundwater flow. Information regarding the mechanisms and elevation of recharge was inferred from the delta-D versus delta-O-18 relationships and differences in isotopic composition, respectively

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Stoessell R. K. , Moore Y. H. , Coke J. G. ,
Dissolution of carbonate minerals in the coastal halocline is taking place in the karst terrain along the northeastern coast of the Yucatan Peninsula. The dissolution is being accelerated in cenotes (sinkholes) where sulfate reduction and oxidation of the produced sulfide is occurring. Hydrogen-sulfide concentrations ranged from 0.06 to 4 mmolal within the halocline in two sinkholes. Relative to concentrations expected by conservative mixing, fluids with high hydrogen-sulfide concentrations were correlated with low sulfate concentrations, high alkalinities, low pH values, and heavy sulfur isotope values for sulfate. Hydrogen-sulfide concentrations were less than those predicted from sulfate reduction, calculated from deficiencies in measured sulfate concentrations, indicating mobility and loss of aqueous sulfide. Fluids with low hydrogen-sulfide concentrations were correlated with very high calcium concentrations, high strontium and sulfate concentrations, slightly elevated alkalinities, low pH values, and sea-water sulfur isotope values for sulfate. Gypsum dissolution is supported by the sulfur isotopes as the major process producing high sulfate concentrations. However, oxidation of aqueous sulfide to sulfuric acid, resulting in carbonate-mineral dissolution is needed to explain the calcium concentrations, low pH values, and only slightly elevated alkalinities. The halocline may trap hydrogen sulfide that has been stripped from the underlying anoxic salt water. The halocline can act as a stable, physical boundary, holding some of the hydrogen sulfide until it is oxidized back to sulfuric acid through interaction with the overlying, oxygenated fresh water or through the activity of sulfide-oxidizing bacteria

Reporting of stable hydrogen, carbon and oxygen abundances, 1994,
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Coplen T. B.

The combined use of Sr-87/Sr-86 and carbon and water isotopes to study the hydrochemical interaction between groundwater and lakewater in mantled karst, 1996,
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Katz B. G. , Bullen T. D. ,
The hydrochemical interaction between groundwater and lakewater influences the composition of water that percolates downward from the surficial aquifer system through the underlying intermediate confining unit and recharges the Upper Floridan aquifer along highlands in Florida. The Sr-87/Sr-86 ratio along with the stable isotopes, D, O-18, and C-13 were used as tracers to study the interaction between groundwater, lakewater, and aquifer minerals near Lake Barco, a seepage lake in the mantled karst terrane of northern Florida. Upgradient from the lake, the Sr-87/Sr-86 ratio of groundwater decreases with depth (mean values of 0.71004, 0.70890, and 0.70852 for water from the surficial aquifer system, intermediate confining unit, and Upper Floridan aquifer, respectively), resulting from the interaction of dilute oxygenated recharge water with aquifer minerals that are less radiogenic with depth. The concentrations of Sr2 generally increase with depth, and higher concentrations of Sr2 in water from the Upper Floridan aquifer (20-35 mu g/L), relative to water from the surficial aquifer system and the intermediate confining unit, result from the dissolution of Sr-bearing calcite and dolomite in the Eocene limestone. Dissolution of calcite [delta(13)C = -1.6 permil (parts per thousand)] is also indicated by an enriched delta(13)C(DIC) (-8.8 to -11.4 parts per thousand) in water from the Upper Floridan aquifer, relative to the overlying hydrogeologic units (delta(13)C(DIC) < -16 parts per thousand). Groundwater downgradient from Lake Barco was enriched in O-18 and D relative to groundwater upgradient from the lake, indicating mixing of lakewater leakage and groundwater. Downgradient from the lake, the Sr-87/Sr-86 ratio of groundwater and aquifer material become less radiogenic and the Sr2 concentrations generally increase with depth. However, Sr2 concentrations are substantially less than in upgradient groundwaters at similar depths. The lower Sr2 concentrations result from the influence of anoxic lakewater leakage on the mobility of Sr2 from clays. Based on results from mass-balance modeling, it is probable that cation exchange plays the dominant role in controlling the Sr-87/Sr-86 ratio of groundwater, both upgradient and downgradient from Lake Barco. Even though groundwater from the three distinct hydrogeologic units displays considerable variability in Sr concentration and isotopic composition, the dominant processes associated with the mixing of lakewater leakage with groundwater, as well as the effects of mineral-water interaction, can be ascertained by integrating the use of stable and radiogenic isotopic measurements of groundwater, lakewater, and aquifer minerals

Tracing recharge from sinking streams over spatial dimensions of kilometers in a karst aquifer, 1997,
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Greene E. A. ,
Stable isotopes of hydrogen and oxygen were used to trace the sources of recharge from sinking streams to wells and springs several kilometers downgradient in the karst Madison aquifer near Rapid City, South Dakota. Temporal sampling of streamflow above the swallets identified a distinct isotopic signature that was used to define the spatial dimensions of recharge to the aquifer. When more than one sinking stream was determined to be recharging a well or spring, the proportions were approximated using a two-component mixing model. From the isotopic analysis, it is possible to link sinking stream recharge to individual wells or springs in the Rapid City area and illustrate there is significant lateral movement of ground water across surface drainage basins. These results emphasize that well-head protection strategies developed for carbonate aquifers that provide industrial and municipal water supplies need to consider lateral movement of ground-water flow from adjacent surface drainage basins

An experimental study of calcite and limestone dissolution rates as a function of pH from -1 to 3 and temperature from 25 to 80 degrees C, 1998,
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Alkattan M, Oelkers Eh, Dandurand Jl, Schott J,
Dissolution rates of single calcite crystals, limestones, and compressed calcite powders were determined from sample weight loss using free-drift rotating disk techniques. Experiments were performed in aqueous HCl solutions over the bulk solution pH range -1 to 3, and at temperatures of 25 degrees, 50 degrees, and 80 degrees C. Corresponding rates of the three different sample types are identical within experimental uncertainty. Interpretation of these data using equations reported by Gregory and Riddiford [Gregory, D.P., Riddiford, A.C., 1956. Transport to the surface of a rotating disc. J. Chem. Sec. London 3, 3756-3764] yields apparent rate constants and H diffusion coefficients. The logarithms of overall calcite dissolution rates (r) obtained at constant disk rotation speed are inversely proportional to the bulk solution pH, consistent with r = k(2') a(H,b), where k(2)' stands for an apparent rate constant and a(H,b) designates the hydrogen ion activity in the bulk solution, This variation of dissolution rates with pH is consistent with corresponding rates reported in the literature and the calcite dissolution mechanism reported by Wollast [Wollast, R., 1990. Rate and mechanism of dissolution of carbonates in the system CaCO3-MgCO3. In: Stumm, W. (Ed.), Aquatic Chemical Kinetics. Wiley, pp. 431-445]. Apparent rate constants for a disk rotation speed of 340 rpm increase from 0.07 0.02 to 0.25 0.02 mol m(-2) s(-1) in response to increasing temperature from 25 degrees to 80 degrees C. H diffusion coefficients increase from (2.9 to 9.2) x 10(-9) m(2) s(-1) over this temperature range with an apparent activation energy of 19 kJ mol(-1). (C) 1998 Elsevier Science B.V. All rights reserved

Seasonal Effects on the Geochemical Evolution of the Logsdon River, Mammoth Cave, Kentucky., 1998,
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Anthony, Darlene M. , Ms

The following research describes the collection and evaluation of geochemical data from the Logsdon River, an open-flow conduit that drains a portion of the Turnhole Spring drainage basin within the Mammoth Cave karst aquifer of south-central Kentucky. This spatial survey of nearly 10 km of continuous base-level conduit included seasonal sampling of carbon dioxide partial pressures (PCO2), dissolved ions, and saturation indices for calcite (SIcal). The highest PCO2 are found at the upstream site closest to the Sinkhole Plain recharge area, which creates undersaturated conditions. Rapid outgassing of CO2 into the cave atmosphere creates oversaturated conditions for several thousand meters. This change in chemistry results in the accumulation of travertine in these areas. A boost in PCO2 roughly half-way through the flow path returns the water to slightly undersaturated conditions. The most likely source for additional CO2 is in-cave organic decay, as the boost also occurs during winter months when microbial activity in the soil is at a minimum. A general decline in Ca2+, Mg2+, and HCO3- concentrations occurred over the distance through the Logsdon River conduit. This decline may reflect a diluting of water by localized inputs from the Mammoth Cave Plateau and precipitation of travertine along the flow path. Although values for all parameters are greater in summer than winter, the trend in evolution is similar for both seasonal extremes.
The nature of the transition from summer to winter conditions in the aquifer was investigated by way of an intensive study of the geochemistry at the Logsdon River monitoring well. The relationship between conductivity (spC) and pH was evaluated during both seasons in an attempt to predict the activity of hydrogen for any given water sample, based on continuous spC measurements at the well. Data collected during the 1997-98 seasonal transitions supported a single, nonlinear regression equation that may represent two distinct seasonal regimes.

Stable isotopes as natural tracers of the karst recharge to the tertiary clastic aquifers: a case study of southern part of Ljubljana marsh , 1998,
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Pezdič, Jož, E,

The main purpose of the research was to determine the recharge and storage of groundwater at the southern part of Ljubljana marsh where tertiary aquifers are filled mainly with karst water. Stable isotopes of hydrogen, oxygen and carbon in water or in dissolved species, as well as tritium content in water and precipitation were used as natural tracers to follow the recharge and discharge of surface streams and aquifers. Together with hydrogeological and other chemical evidence they provide useful information about water mass transport, storage, refilling of aquifers and mixing of groundwater. In the aquifers, springs and surface river water d18O varied from -9,65 to -8,82 š while dD has the range from -67,4 to -61,2 š. Tritium activities are measured from 1,6 to 13,4 T.U.. Long term averages (n = 13 years) for d18O (dD) in Ljubljana is -8,73 (-60,6) š and tritium content is 17,5 T.U.. The mean temperature in Ljubljana is 10,03ºC and average years precipitation amount is 1332 mm. Years 1992-93 have been characterised by low tritium content in precipitation (8,2 for 1992 and 10,6 for 1993) and so important for investigation. The average mean meteoric line for the last 14 years is defined as dD=8,188xd18O+10,66. Temperature correlation vs. oxygen is: d18O=0,254xt-10,78. The above database is discussed in order to evaluate thesis about karst influence on the recharge and storage of clastic sediment aquifers in the Iška delta sediment structure.

Cueva de Villa Luz, Tabasco, Mexico: Reconnaissance Study of an Active Sulfur Spring Cave and Ecosystem, 1999,
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Hose, L. D. , Pisarowicz, J. A.
Cueva de Villa Luz (a.k.a. Cueva de las Sardinas) in Tabasco, Mexico, is a stream cave with over a dozen H2S-rich springs rising from the floor. Oxidation of the H2S in the stream results in abundant, suspended elemental sulfur in the stream, which is white and nearly opaque. Hydrogen sulfide concentrations in the cave atmosphere fluctuate rapidly and often exceed U.S. government tolerance levels. Pulses of elevated carbon monoxide and depleted oxygen levels also occasionally enter the cave. Active speleogenesis occurs in this cave, which is forming in a small block of Lower Cretaceous limestone adjacent to a fault. Atmospheric hydrogen sulfide combines with oxygen and water to form sulfuric acid, probably through both biotic and abiotic reactions. The sulfuric acid dissolves the limestone bedrock and forms gypsum, which is readily removed by active stream flow. In addition, carbon dioxide from the reaction as well as the spring water and cave atmosphere combines with water. The resultant carbonic acid also dissolves the limestone bedrock. A robust and diverse ecosystem thrives within the cave. Abundant, chemoautotrophic microbial colonies are ubiquitous and apparently act as the primary producers to the caves ecosystem. Microbial veils resembling soda straw stalactites, draperies, and u-loops suspended from the ceiling and walls of the cave produce drops of sulfuric acid with pH values of <0.5-3.0 0.1. Copious macroscopic invertebrates, particularly midges and spiders, eat the microbes or the organisms that graze on the microbes. A remarkably dense population of fish, Poecilia mexicana, fill most of the stream. The fish mostly eat bacteria and midges. Participants in an ancient, indigenous Zoque ceremony annually harvest the fish in the spring to provide food during the dry season.

Bedrock Features of Lechuguilla Cave, Guadalup Mountains, New Mexico, 2000,
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Duchene, H. R.
Lechuguilla is a hypogenic cave dissolved in limestones and dolostones of the Capitan Reef Complex by sulfuric acid derived from oil and gas accumulations in the Delaware Basin of southeast New Mexico and west Texas. Most of the cave developed within the Seven Rivers and Capitan Formations, but a few high level passages penetrate the lower Yates Formation. The Queen and possibly Goat Seep formations are exposed only in the northernmost part of the cave below -215 m. Depositional and speleogenetic breccias are common in Lechuguilla. The cave also has many spectacular fossils that are indicators of depositional environments. Primary porosity in the Capitan and Seven Rivers Formations was a reservoir for water containing hydrogen sulfide, and a pathway for oxygenated meteoric water prior to and during sulfuric acid speleogenesis. Many passages at depths >250 m in Lechuguilla are in steeply dipping breccias that have a west-southwest orientation parallel to the strike of the shelf margin. The correlation between passage orientation and depositional strike suggests that stratigraphy controls these passages.

Hydrochemical Interpretation of Cave Patterns in the Guadalupe Mountains, New Mexico, 2000,
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Palmer, A. N. , Palmer, M. V.
Most caves in the Guadalupe Mountains have ramifying patterns consisting of large rooms with narrow rifts extending downward, and with successive outlet passages arranged in crude levels. They were formed by sulfuric acid from the oxidation of hydrogen sulfide, a process that is now dormant. Episodic escape of H2S-rich water from the adjacent Delaware Basin, and perhaps also from strata beneath the Guadalupes, followed different routes at different times. For this reason, major rooms and passages correlate poorly between caves, and within large individual caves. The largest cave volumes formed where H2S emerged at the contemporary water table, where oxidation was most rapid. Steeply ascending passages formed where oxygenated meteoric water converged with deep-seated H2S-rich water at depths as much as 200 m below the water table. Spongework and network mazes were formed by highly aggressive water in mixing zones, and they commonly rim, underlie, or connect rooms. Transport of H2S in aqueous solution was the main mode of H2S influx. Neither upwelling of gas bubbles nor molecular diffusion appears to have played a major role in cave development, although some H2S could have been carried by less-soluble methane bubbles. Most cave origin was phreatic, although subaerial dissolution and gypsum-replacement of carbonate rock in acidic water films and drips account for considerable cave enlargement above the water table. Estimates of enlargement rates are complicated by gypsum replacement of carbonate rock because the gypsum continues to be dissolved by fresh vadose water long after the major carbonate dissolution has ceased. Volume-for-volume replacement of calcite by gypsum can take place at the moderate pH values typical of phreatic water in carbonates, preserving the original bedrock textures. At pHs less than about 6.4, this replacement usually takes place on a molar basis, with an approximately two-fold volume increase, forming blistered crusts.

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