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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 sliding is 1. the relative displacement of two bodies along a surface, without loss of contact between the bodies. 2. the downslope movement of rock and earth material [16].?

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


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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 groundwaters (Keyword) returned 67 results for the whole karstbase:
Showing 16 to 30 of 67
HYDROGEOCHEMISTRY OF GRAND-CAYMAN, BRITISH-WEST-INDIES - IMPLICATIONS FOR CARBONATE DIAGENETIC STUDIES, 1995,
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Ng K. C. , Jones B. ,
Groundwater in the dolostone aquifers of the Bluff Group (Oligocene-Miocene) on Grand Cayman is divided into fresh, lightly and highly brackish, and saline (Type I and II) zones according to chemical characteristics that were determined during a 3 year (1985-1988) monitoring program. Brackish and Type I saline waters display the greatest variation in chemical properties whereas the Type II saline water has the most stable chemical characteristics. Most groundwaters from these dolostone aquifers are thermodynamically capable of precipitating calcite and/or dolomite. The saturation indices for these minerals, however, vary through time and space even in the context of small water lens. Simple mixing of fresh and sea water cannot explain the chemistry of the water found in the joint and karst controlled dolostone aquifers of Grand Cayman. Deviation from a simple mixing model is due to variations caused by tidal fluctuation, the rate of rain water recharge, influx of Ca-rich groundwater from the surrounding limestone aquifers, influx of CO2-rich surface water from sinkholes and swamps, and water-rock interactions (dissolution and precipitation of calcite and dolomite). Sustained groundwater abstraction from a lens can significantly alter the hydrochemistry of the water lens. This suggests that hydrochemical characterization of small fresh water lenses, like those on Grand Cayman, cannot be based on spot or short-term sampling. Interpretation of such fluids in terms of calcite-dolomite precipitation and/or dissolution must be treated with caution if the data base has not been derived from long-term monitoring

Radiocarbon concentration and origin of thermal Karst waters in the region of the Bukk Mountains, northeastern Hungary, 1995,
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Hertelendi E. , Veres M. , Futo I. , Svingor E. , Miko L. , Lenart L. , Deak J. , Suveges M. ,
Karst springs are abundant in Hungary, and many are thermal (temperatures >30 degrees C). As thermal springs are a significant part of Hungary's water resources, it is important to quantify their travel times in the karst systems. Thus, we chose to measure T and delta(18)O in the water and delta(13)C and C-14 in dissolved inorganic carbon (DIC) in water from 50 thermal and nonthermal springs and wells in the Bukk Mountains, northeastern Hungary, Environmental isotope data confirm the karst waterflow pattern implied by earlier studies. We found the water in warm springs and boreholes to be mixtures of cold young and old thermal water. We also determined short mean-residence times for some large cold springs. The C-14 activities measured in these springs indicate that the recharge area of the karst aquifer is open to the atmosphere, and atmospheric CO2 contributes to the C-14 activity of these groundwaters. We observed good correlation between C-14 and H-3 activities and we determined negative correlations between C-14 concentration and delta(13)C values and temperature. From the delta(18)O values of the oldest thermal waters, we attribute their origin to precipitation during colder temperatures than at present

Symposium Abstract: Chemical and isotopic evidence for processes affecting shallow and deep groundwaters in the Derbyshire dome, 1996,
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Bottrell S. H. , Webber N.

Paleokarst phenomena as 'targets' for modern karst groundwaters: the contrasts between thermal water and meteoric water behaviour., 1996,
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Ford D. C.

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

Aufeis of the Firth River basin, Northern Yukon Canada: Insights into permafrost hydrogeology and Karst, 1997,
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Clark Id, Lauriol B,
The 31-km(2) aufeis ice sheet of the upper Firth River holds a wealth of information on groundwater hydrology in periglacial environments. Baseflow recession calculations, corrected for aufeis storage (12% of basin discharge), indicate specific groundwater recharge rates of up to 100 mm yr(-1) (up to 50% of runoff), suggesting a significant proportion of drainage from karst. The upper Firth River aufeis is a composite aufeis, with discrete baseflow contributions from different watersheds. Since the late Pleistocene, annual growth of the aufeis has exerted a strong control on lateral erosion and the local river channel geomorphology. Two groundwater recharge processes are distinguished on the basis of carbonate geochemistry and 8(13)C: (1) Methanogenic groundwaters, with C-13(DIC) up to -3.3 parts per thousand, are recharged through saturated soils underlain by permafrost; conditions which support anaerobic consumption of dissolved organic carbon (DOC) and produce up to 700 mu g-CH4 L-1 (calculated), and (2) Karst groundwaters, with C-13-depleted DIC, recharged through unsaturated soils and circulate through fissured talik in the carbonate bedrock. Most drainage from the region shows varying contributions of these two groundwaters, although a greater contribution from the methanogenic groundwaters occurs in north-facing watersheds. The 8(13)C values far cryogenic calcite precipitates in the ice indicate that the karst groundwaters are the major contribution to aufeis growth. The combined use of 8(13)C(DIC) and geochemistry may be a useful tool to quantify methanogenesis in northern watersheds

Dedolomitization as a driving mechanism for karst generation in Permian Blaine formation, southwestern Oklahoma, USA, 1997,
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Raines M. A. , Dewers T. A. ,
Cyclic deposits of Permian shales, dolomites, and halite and gypsum-bearing strata in the Blaine Formation of Southwestern Oklahoma contain abundant karst features. The present study shows that an important mechanism of karst development in these sequences is dedolomitization, wherein gypsum and dolomite in close spatial proximity dissolve and supersaturate groundwaters with respect to calcite. The net loss of mass accompanying this process (dolomite and gypsum dissolution minus calcite precipitation) can be manifest in secondary porosity development while the coupled nature of this set of reactions results in the retention of undersaturated conditions of groundwater with respect to gypsum. The continued disequilibrium generates karst voids in gypsum-bearing aquifers, a mineral-water system that would otherwise rapidly equilibrate. Geochemical modeling (using the code PHRQPITZ, Plummer et al 1988) of groundwater chemical data from Southwestern Oklahoma from the 1950's up to the present suggests that dedolomitization has occurred throughout this time period in evaporite sequences in Southwestern Oklahoma. Reports from groundwater well logs in the region of vein calcite suggest secondary precipitation, an observation in accord with dedolomite formation In terms of the amounts of void space produced by dissolution, dedolomitization can dominate gypsum dissolution alone, especially in periods of quiescent aquifer recharge when gypsum-water systems would have otherwise equilibrated and karst development ceased. Mass balance modeling plus molar volume considerations show that for every cubic cm of original rock (dolomite plus gypsum), there is 0.54 cm(3) of calcite and 0.47 cm(3) of void space produced Only slightly more pore space results if the dedolomitization reaction proceeds by psuedomorphic replacement of dolomite by calcite than in a reaction mechanism based on conservation of bicarbonate

Elevated and variable values of 13C in speleothems in a British cave system, 1997,
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Baker A, Ito E, Smart Pl, Mcewan Rf,
[delta] 13C isotope variations in speleothems have been investigated for samples from the British Isles, where plants which use the Hatch-Slack or C4 photosynthetic pathway are not present. The range of [delta] 13C expected in speleothem carbonate formed in isotopic equilibrium with soil CO2 derived from the overlying C3 vegetation should thus fall in the range -12 to -6[per mille sign]. Forty-one actively growing speleothem samples from low-discharge sites were analysed from Stump Cross Caverns, Yorkshire, England. Ten percent have [delta] 13C greater than -6%. In addition, a large range of [delta] 13C was observed (-8.06 1.38[per mille sign], a 1 [sigma] variability of 17%), with adjacent samples having [delta] 13C differing by a maximum of 4.74[per mille sign]. Similar findings were obtained from a review of analyses of late Quaternary speleothem samples from the British Isles, with 75% of flowstone samples and 57% of high-flow stalagmite samples exhibiting elevated [delta] 13C. Three possible processes are proposed as possible causes of elevated [delta] 13C in speleothems. Firstly, fractionation may occur between the stalactite and stalagmite due to evaporation or degassing. Secondly, degassing of the groundwaters may have occurred within the aquifer before reaching the cave void, allowing release of some CO2 from the water whilst remaining saturated in calcium. Finally, the elevated [delta] 13C may be due to short water residence times in the soil, such that equilibrium between soil water and soil CO2 is not reached. Evidence presented here demonstrates that any one of these mechanisms may be important in the karst areas of the British Isles. Caution is needed before interpreting the [delta] 13C signal within speleothems in terms of palaeovegetation

Geology, geochemistry, and origin of the continental karst-hosted supergene manganese deposits in the western Rhodope massif, Macedonia, northern Greece, 1997,
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Nimfopoulos M. K. , Pattrick R. A. D. , Michailidis K. M. , Polya D. A. , Esson J. ,
Economic Mn-oxide ore deposits of commercial grade occur in the Rhodope massif near Kato Nevrokopi in the Drama region, Northern Greece. The Mn-oxide mineralization has developed by weathering of continental hypogene rhodochrosite-sulphide veins. The vein mineralization is confined by tectonic shear zones between marble and metapelites, extending laterally into the marble as tabular, pod or lenticular oreshoots (up to 50 m x 20 m x 5-10 m). Supergene oxidation of the hypogene mineralization led to the formation of in-situ residual Mn-oxide ore deposits, and secondary infills of Mn-oxide ore in embryonic and well developed karst cavities. Whole rock geochemical profiles across mineralized zones confirm the role of thrusts and faults as solution passageways and stress the importance of these structures in the development of hydrothermal and supergene mineralization at Kato Nevrokopi. Three zones an recognized in the insitu supergene veins: (A) a stable zone of oxidation, where immobile elements form (or substitute in) stable oxide mineral phases, and mobile elements are leached; (B) a transitional (active) zone in which element behavior is strongly influenced by seasonal fluctuations of the groundwater table and variations in pH-Eh conditions; and (C) a zone of permanent flooding, where variations in pH-Eh conditions are minimal. Zone (B) is considered as the source zone for the karst cavity mineralization. During weathering, meteoric waters, which were CO2-rich (P-CO2 similar to 10(-3.8) to 10(-1.4)) and oxygenated (fO(2) -10(-17) for malachite), percolated downward within the veins, causing breakdown and dissolution of sulfides and marble, and oxidation of rhodochrosite to Mn-oxides. Karat cavity formation was favored by the high permeability along thrust zones. Dissolved Mn2 was transported into karst cavities in reduced meteoric waters at the beginning of weathering (pH similar to 4-5), and as Mn(HCO3)(2) in slightly alkaline groundwaters during advanced weathering (pH similar to 6-8). Mn4? precipitation took place by fO(2) increase in ground waters, or pH increase by continuous hydrolysis and carbonate dissolution. In the well developed karst setting, some mobility of elements occurred during and after karst ore formation in the order Na>K>Mg>Sr>Mn>As>Zn>Ba>Al>Fe>Cu>Cd>Pb. (C) 1998 Canadian Institute of Mining, Metallurgy and Petrolem. Published by Elsevier Science Ltd. All rights reserved

Environmental isotope study of the major karst springs in Damascus limestone aquifer systems: Case of the Figeh and Barada springs, 1997,
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Kattan Z. ,
The groundwaters of major karst springs and several piezometers and wells in the Damascus limestone aquifer systems (Syria) have been investigated using chemical and environmental isotope techniques. The groundwater bodies of major karat springs mainly originate from direct infiltration of atmospheric water. The groundwaters emerging from the Figeh main spring have lower stable isotope concentrations than those emerging from the Barada spring. Stable isotopes show that the elevation of the recharge zones of the Figeh main spring (1750 m above sea level) is higher than those for the Figeh side spring (1500 m) and the Harouch spring (1300 m). The groundwater in the Barada spring seems to be recharged in a catchment area with a mean elevation of about 1250 m. The temporal evolution of stable isotope concentrations, tritium content and hydrochemistry show the existence of an interconnection between the aquifers of the Figeh main spring and the Figeh side spring, especially during flood periods. The distinct independent isotopic composition of Harouch spring from those of Figeh main and side springs suggests no interconnection with the Figeh aquifers. Adopting a model with exponential time distribution, the mean turnover time (residence time) of groundwater in Figeh main spring was evaluated to be 50 years. On the basis of this evaluation, a value of about 3.9 billion m(3) was obtained for the maximum groundwater reservoir size. (C) 1997 Elsevier Science B.V

Groundwater circulation and geochemistry of a karstified bank-marginal fracture system, South Andros Island, Bahamas, 1997,
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Whitaker Fiona F. , Smart Peter L. ,
On the east coast of South Andros Island, Bahamas, a major bank-marginal fracture system characterised by vertically extensive cavern systems (blue holes) is developed sub-parallel to the steep-sided deep-water re-entrant of the Tongue of the Ocean. In addition to providing a discharge route for meteoric, mixed and geochemically evolved saline groundwaters, a strong local circulation occurs along the fracture system. This generates enhanced vertical mixing within voids of the fracture system, evidenced by the increasing mixing zone thickness, and the thinning and increasing salinity of brackish lens waters from north to south along the fracture system. Furthermore, tidally driven pumping of groundwaters occurs between the fracture and adjacent carbonate aquifer affecting a zone up to 200 m either side of the fracture.The resultant mixing of groundwaters of contrasting salinity and within and along the fracture system and with the surrounding aquifer waters, together with bacterial oxidation of organic matter, generates significant potential for locally enhanced diagenesis. Undersaturation with respect to calcite within the fresh (or brackish)-salt water mixing zone is observed in the fracture system and predicted in the adjacent aquifer, while mixing between the brackish fracture lens and surrounding high fresh waters causes dissolution of aragonite but not calcite. The latter gives rise to considerable secondary porosity development, because active tidal pumping ensures continued renewal of dissolutional potential. This is evidenced by calcium and strontium enrichment in the brackish lens which indicates porosity generation by aragonite dissolution at a maximum rate of 0.35% ka-1, up to twice the average estimated for the fresh water lens. In contrast saline groundwaters are depleted in calcium relative to open ocean waters suggesting the formation of calcite cements.The development of a major laterally continuous cavernous fracture zone along the margin of the carbonate platform permits enhanced groundwater flow and mixing which may result in generation of a diagenetic `halo' at a scale larger than that generally recognised around syn-sedimentary fractures in fossil carbonates. This may be characterised by increased secondary porosity where a relative fall in sea-level results in exposure and formation of a meteoric groundwater system, or cementation by `marine' calcite both below this meteoric system, and where the bank surface is flooded by seawater

Determination of bacteriophage migration and survival potential in karstic groundwaters using batch agitated experiments and mineral colloidal particles, 1997,
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Formentin K. , Rossi P. , Aragno M. , Miiller I.

Fluorescence wavelength and intensity variations of cave waters, 1999,
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Baker A, Genty D,
The fluorescence properties of groundwaters percolating into four cave systems have been monitored over the period 1997-1998. Fluorescence was excited between 220 and 400 nm and the emission measured from 300 to 500 nm using a fluorescence spectrophotometer. Three fluorescence centres were observed; one at the excitation-emission pair of 290-340:395-430 nm, (humic-like, probably fulvic acid), one at 265-280:300-370 nm (protein like) and a less defined region of high fluorescence at 230-280:310-420 nm (humic and/or protein like). The most consistent fluorescence intensity was observed in the excitation-emission pair of 290-340:395-430 nm, attributed to a fulvic acid source. Subtle differences (5%) in the fluorescence excitation and emission wavelength of this fluorescence peak in the groundwater were observed between the four sites, and the fluorescence intensity varied considerably ( x 60) between the four sites. Both the wavelength and the intensity variations in fluorescence are caused by the differences in the vegetation cover, soil type and humification. Data from the most intensely monitored site (Brown’s Folly Mine, England; 9 sample stations, 10-20 days frequency sampling) revealed no spatial variability in the 290-340:395-430 nm (fulvic acid) fluorescence; in contrast time-series analysis suggests that the seasonal variations do occur, with a decrease in the emission wavelength correlating with the first (autumn) peak in fluorescence intensity, and a decrease in the excitation wavelength correlating with a second (winter) fluorescence intensity peak. Results demonstrate the potential of utilising fluorescence wavelength variations in sourcing karst groundwaters, and as a possible palaeoenvironmental proxy of the overlying soil conditions if trapped within the cave speleothems

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

The geochemistry of sulphur in a mixed allogenic-autogenic karst catchment, Castleton, Derbyshire, UK, 2000,
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Bottrell Sh, Webber N, Gunn J, Worthington Srh,
Analyses are presented of anion chemistry and sulphur isotopic compositions of sulphate in sinking streams and groundwaters in a mixed allogenic-autogenic karst catchment. Using the sulphur isotopic data, sources of sulphate from agriculture and the effects of sulphate reduction arising from slurry application can be distinguished from natural rock weathering sources. Within the aquifer, sulphate in known autogenic waters has isotopic compositions distinct from allogenic waters, the autogenic waters being dominated by sulphate from rainfall and rock weathering in these low agricultural intensity catchments. On this basis, water rising at low flow from Whirlpool Rising, Speedwell Cavern, has been identified as dominantly autogenic. Groundwater flow between the sinks and risings in Speedwell Cavern is believed to be along conduits following mineralized faults (rakes). During transit SO42-/Cl- in the water increases. Isotopic mass balance shows that this must be due to addition of sulphate from the oxidation of ore minerals by groundwater. Mass balance considerations show that the present rate of sulphide oxidation must be the result of enhancement by lead mining operations on the rakes. Copyright (C) 2000 John Wiley & Sons, Ltd

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