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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 tube, lava is see lava cave.?

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.
See all featured articles
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;
See all featured articles from other geoscience journals

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Your search for c-14 (Keyword) returned 19 results for the whole karstbase:
Showing 1 to 15 of 19
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Horvatincic N. , Srdoc D. , Silar J. , Tvrdikova H. ,
C-14 activity of dissolved inorganic carbon (DIC) in water and in recent tufa samples in several karst areas of Yugoslavia and Czechoslovakia was measured. Groundwater from 11 karst springs were measured for their isotopic content (C-14, H-3, C-13), chemical composition (HCO3, Ca2, Mg2) and physico-chemical properties (temperature, pH). Seasonal variations of the C-14 activity of DIC in two karst springs in Plitvice Lakes area, Yugoslavia, were measured systematically from 1979-1987. C-14 activity of recent tufa samples from several locations downstream were also measured. The activity of DIC in karst spring water in both countries ranged from 63-87 pMC, which is attributed to differences in geologic structure of the recharge area, topsoil thickness and composition. Grouping of C-14 activities of DIC ca (824)% is evident. Tritium activity at all the springs indicated short mean residence time (1-10 yr). Concentration of HCO3, Ca2 and Mg2 in spring water varied with geomorphology. C-14 activity of streamwater and recent tufa increased downstream from karst springs due to the exchange between atmospheric CO2 and DIC

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Magnin F. , Guendon J. L. , Vaudour J. , Martin P. ,
In the valleys of southeastern France, below karst massifs, river deposits with travertines show vertical sedimentary sequences always similar, with, from bottom to top: gravels, silts, chalks, travertines s.s. (stromatolitic encrustations with laminated facies), travertinous sand, silts. The study of flora and fauna fossilized by these formations shows a good correlation between the maximum of carbonate deposition (travertinous facies s.s.) and the optimum of vegetation development (forest). And finally, behind calcareous dams edified by travertine, paludal and lacustrine fields are environments developed trapping diversified sediments (clays, peats, silts,...). Then, dam and lake are forming a unit that we can call a 'travertine system'

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Adatte T, Rentzel P, Kubler B,
Mineralogical and sedimentological investigations were carried out on a karst filling located in the Cotencher cave (Neuchatel, Jura mountains, Switzerland). Radiometric and archeological dating give evidence for a rather incomplete record of the climatic history of the last glacial period. The major hiatus is situated in the younger Wurmian Pleniglacial age. Following the mineralogical and sedimentological results, it is possible to divide this profile in three parts. Late glacial and holocene sediments are characterized by fine morainic material, redeposited due to karst activity. The middle part (C-14: > 40 Ky BP), directly located below this hiatus shows a typical mineralogical association with the appearance of kaolinite and the persistance of the amphibole. This association is thought to be of eolian origin, older than the one described on the Jura mountains actual soils. This eolian sediment component was deposited after the early Wurmian Pleniglacial period. on the soils in the vicinity of the cave, and resedimented into the cave during the Wurmian Interpleniglacial. The lower part of the sediment column is characterized by a mineralogical association of kaolinite, mixed-layers and mica. Especially high amounts of kaolinite, possibly derived from old, probably Eemian mature soils give evidence for relatively warm climate with strong seasonal variations

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Drysdale R, Head J,
Louie Creek is a karst springfed stream situated in the seasonally humid tropics of northwest Queensland, Australia. It rises as a series of small exsurgences along the eastern edge of the Barkly Tableland. As it enters the lowlands of the Carpentaria plain, the creek deposits tufa which produces a series of cascades. This modern tufa extends discontinuously for about 1.5 km. A series of ancient tufas, in places lying adjacent to sites of modern deposition, extends discontinously for about 8 km downstream. At least two ancient tufa units are preserved at one location, Little Indarri site. The older unit comprises a sequence of well-preserved barrages with an orientation transverse to present-day stream flow. In places, erosion has reduced these barrages to their calcrete substrate. The older tufa is overlain in places by sediment which has become cemented to form a second calcrete unit. This sediment is in turn succeeded by the younger ancient tufa. Subsequent river incision has removed part of the sediment from the older unit and exposed several contact points between the ancient tufa and calcrete units. Radiocarbon dating of the Little Indarri site tufas, as well as other ancient Louie Creek units, yielded apparent ages ranging from approximately 30 to approximately 14 ka BP, suggesting that conditions were sufficiently wet during the period immediately preceding and throughout the Last Glacial Maximum for tufa deposition to occur. However, ancient tufa formation occurred during a phase of net river aggradation. There is geomorphic evidence that such aggradation was a result of an increased sediment supply to the fluvial system, most likely in response to conditions drier than present. Results from studies elsewhere in the region support such a Late Pleistocene trend. Incision of Louie Creek, which postdates the youngest of the dated ancient tufas, is most likely to have resulted from a shift to wetter conditions during the early Holocene

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Frumkin A, Ford Dc,
Rock salt is approximately 1000 times more soluble than limestone and thus displays high rates of geomorphic evolution. Cave stream channel profiles and downcutting rates were studied in the Mount Sedom salt diapir, Dead Sea rift valley, Israel. Although the area is very arid (mean annual rainfall approximate to 50 mm), the diapir contains extensive karst systems of Holocene age. In the standard cave profile a vertical shaft at the upstream end diverts water from a surface channel in anhydrite or elastic cap rocks into the subsurface route in the salt. Mass balance calculations in a sample cave passage yielded downcutting rates of 0.2 mm s(-1) during peak flood conditions, or about eight orders of magnitude higher than reported rates in any limestone cave streams. However, in the arid climate of Mount Sedom floods have a low recurrence interval with the consequence that long-term mean downcutting rates are lower: an average rate of 8.8 mm a(-1) was measured for the period 1986-1991 in the same sample passage. Quite independently, long-term mean rates of 6.2 mm a(-1) are deduced from C-14 ages of driftwood found in upper levels of 12 cave passages. These are at least three orders of magnitude higher than rates established for limestone caves. Salt cave passages develop in two main stages: (1) an early stage characterized by high downcutting rates into the rock salt bed, and steep passage gradients; (2) a mature stage characterized by lower downcutting rates, with establishment of a subhorizontal stream bed armoured with alluvial detritus. In this mature stage downcutting rates are controlled by the uplift rate of the Mount Sedom diapir and changes of the level of the Dead Sea. Passages may also aggrade. These fast-developing salt stream channels may serve as full-scale models for slower developing systems such as limestone canyons

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

Paleoclimatic implications of radiocarbon dating of speleothems from the Cracow-Wielun Upland, southern Poland, 1995,
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Pazdur A. , Pazdur M. F. , Pawlyta J. , Gorny A. , Olszewski M. ,
We report preliminary results of a long-term systematic study intended to gather paleoclimatic records from precisely dated speleothems. The research project is limited to speleothems deposited in caves of the Cracow-Wielun Upland, the largest and best-explored karst region in Poland, covering ca. 2900 km(2) with >1000 caves. Speleothem samples were selected from collections of the Geological Museum of the Academy of Mining and Metallurgy in Cracow. Radiocarbon dates of these samples from ca. 45-20 ka BP almost exactly coincide with age range of the Interplenivistulian. A break in speleothem formation between ca. 20 and 10 ka up may be interpreted as a result of serious climatic deterioration associated with the maximum extent of the last glaciation. We observed differences among C-14, U/Th and AAR dating results. Changes of delta(13)C and delta(18)O in speleothems that grew between ca. 30 and 20 ka sp may be interpreted as changes of paleoclimatic conditions

Sensitivity of karst process to environmental change along the Pep II transect, 1997,
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Yuan D. X. ,
It has been known since as early as the last century that karst formation is a geologic process related to chemical reaction, but not until the last couple of decades were karst processes viewed as being sensitive to environmental change. The direction and intensity of karst processes are controlled by environmental factors such as temperature, climate, hydrology, vegetation, geology, and the openness of the system to the atmosphere. Accordingly, karst features, as a product of the carbon cycle, differ in space and time. This is clearly evident from the world karst correlation project, IGCP 299. There is a sharp contrast between karst types on both sides of the Qingling Mountain range of central China. Semi-arid karst is located to the north, and humid subtropical karst to the south. Karst features are capable of recording high resolution paleoclimatic change. AMS C-14, isotope and geochemical studies of thin laminae from a giant stalagmite located near Guilin, in southern China, have clearly identified rapid climate changes during the past 40 ka. In karst areas with active neotectonism, huge deposits of calcareous travertine record the amount of deeply sourced CO2 emitted into the atmosphere and can aid studies on modem tectonism because of the association of calcareous travertine with active faults.

Holocene development of three isolated carbonate platforms, Belize, central America, 1998,
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Gischler E. , Hudson J. H. ,
Locally operating factors such as topography of the reef basement and exposure to waves and currents rather than regionally effective factors such as the post-glacial sea level rise in the western Atlantic explain the different Holocene developments of the three isolated carbonate platforms Glovers Reef, Lighthouse Reef, and Turneffe Islands offshore Belize. A series of NNE-striking tilted fault-blocks at the passive continental margin forms the deep basement of the Belize reefs. Glovers and Lighthouse Reefs are located on the same fault-block, while Turneffe Islands is situated west of Lighthouse Reef on an adjacent fault-block. The three platforms are surrounded by deep water and have surface-breaking reef rims. Significant differences exist between platform interiors. Glovers Reef has only 0.2% of land and an 18 m deep, well-circulated lagoon with over 800 patch reefs. Lighthouse Reef has 3% of land and a well-circulated lagoon area. Patch reefs are aligned along a NNE-striking trend that separates a shallow western (3 m) and a deeper eastern (8 m) lagoon. Turneffe Islands has 22% of land that is mainly red mangrove. Interior lagoons are up to 8 m deep and most have restricted circulation and no patch reefs. Surface sediments are rich in organic matter. In contrast, the northernmost part of Turneffe Islands has no extensive mangrove development and the well-circulated lagoon area has abundant patch reefs. Holocene reef development was investigated by means of 9 rotary core holes that all reached Pleistocene reef limestones, and by radiometric dating of corals. Maximal Holocene reef thickness reaches 11.7 m on Glovers Reef, 7.9 m on Lighthouse Reef, and 3.8 m on Turneffe Islands. Factors that controlled Holocene reef development include the following. (1) Holocene sea level. The margin of Glovers Reef was flooded by the rising Holocene sea ca. 7500 YBP, that of Lighthouse Reef ca. 6500 YBP, and that of Turneffe Islands between 5400 and 4750 YBP. All investigated Holocene reefs belong to the keep-up type, even though the three platforms were flooded successively and, hence, the reefs had to keep pace with different rates of sea level rise. (2) Pre-Holocene topography. Pleistocene elevation and relief are different on the three platforms. This is the consequence of both tectonics and karst. Different elevations caused successive reef initiation and they also resulted in differences in lagoon depths. Variations in Pleistocene topography also explain the different facies distribution patterns on the windward platforms that are located on the same fault-block. On Lighthouse Reef tectonic structures are clearly visible such as the linear patch reef trend that is aligned along a Pleistocene fault. On Glovers Reef only short linear trends of patch reefs can be detected because the Pleistocene tectonic structures are presumably masked by the higher Holocene thickness. The lower Pleistocene elevation on Glovers Reef is probably a consequence of both a southward tectonic tilt, and stronger karstification towards the south related to higher rainfall. (3) Exposure to waves and currents. Glovers Reef, Lighthouse Reef, and the northernmost part of Turneffe Islands receive the maximum wave force as they are open to the Caribbean Sea. Adjacent lagoons are well-circulated and have luxuriant patch reef growth and no extensive mangrove development. By contrast, most of Turneffe Islands is protected from the open Caribbean Sea by Lighthouse Reef to the east and is only exposed to reduced wave forces, allowing extensive mangrove growth in these protected areas. (C) 1998 Elsevier Science B.V

Carbon stable isotopic composition of karst soil CO2 in central Guizhon, China, 1999,
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Zheng L. P. ,
The delta(13)C values of soil CO2 are less than that of atmosphere CO2 in the karst area. On the soil-air interface, the delta(13)C vlaues of soil CO2 decrease with the increase in soil depth; below the soil-air interface, the delta(13)C values of soil CO2 are invariable. The type of vegetation on the land surface has an influence on the delta(13)C values of soil CO2. Due to the activity of soil microbes, the delta(13)C values of soil CO2 are variable dth seasonal change in grass. Isotopic tracer indicates that atmosphere CO2 has a great deal of contribution to soil CO2 at the lower parts of soil profile

Intra- and inter-annual growth rate of modern stalagmites, 2001,
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Genty D, Baker A, Vokal B,
We measure the factors that determine growth rate (temperature, drip rate, calcium ion concentration) for 31 waters that feed stalagmites within six cave systems throughout Europe. Water samples were collected at a frequency of at least month. to permit the modelling of both inter- and intra-annual growth rate variations, utilising the theory of Wolfgang Dreybrodt (Chem. Geol. 29 (1980) 89-105; Chem. Geol, 32 (1981) 237-245; Dreybrodt, W., 1988, Processes in Karst Systems. Springer-Verlag, Berlin 288 pp.). Inter-annual growth rates were measured using the stalagmites that were associated with the analysed water samples; growth rate was determined from annual lamina counting, specific time markers within the stalagmites, and location of bomb C-14. When compared to theoretically predicted values, a good agreement between theoretical and measured stalagmite growth rates is observed (R-2 = 0.69). When compared to site climate and geochemical parameters, a good correlation is observed between measured growth fate and mean annual temperature for five sites (R-2 = 0.63) and dripwater calcium content (R-2 = 0.61), but not drip rate (R-2 = 0.09). The good correlation with both calcium and temperature is due to soil CO, production being primarily determined by surface temperature and soil moisture. However, when we compare our data to that in the Grotte de Clamouse, a site that has little soil cover, we observe that the growth rate-temperature relationship breaks down due to either the lack of soil CO, production or prior calcite: precipitation. Intra-annual data demonstrates that maximum growth rate occurs when calcium concentrations are high, and that this occurs under different seasons depending on the hydrology of each site. Our results demonstrate a stronger dependence of intra-annual stalagmite growth rate on dissolved calcium ion concentrations than drip rate for the range of drip rates investigated here (0.01 < t < 2drip s(-1)), but for lower drip rates, this factor becomes important in controlling growth rate. We suggest that for well-monitored acid -understood sites, stalagmite growth rate variations can provide useful information for palaeoclimate reconstruction. (C) 2001 Elsevier Science B.V. All rights reserved

Ecological assessment and geological significance of microbial communities from Cesspool Cave, Virginia, 2001,
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Engel As, Porter Ml, Kinkle Bk, Kane Tc,
Microbial mats from hydrogen sulfide-rich waters and cave-wall biofilms were investigated from Cesspool Cave, Virginia, to determine community composition and potential geomicrobiological functioning of acid-producing bacteria. Rates of microbial mat chemoautotrophic productivity were estimated using [C-14]-bicarbonate incorporations and microbial heterotrophy was determined using [C-14]-leucine incubations. Chemoautotrophic fixation was measured at 30.4 12.0 ng C mg dry wt(1) h(1), whereas heterotrophic productivity was significantly less at 0.17 0.02 ng C mg dry wt(1) h(1). The carbon to nitrogen ratios of the microbial mats averaged 13.5, indicating that the mats are not a high quality food source for higher trophic levels. Ribosomal RNA-based methods were used to examine bacterial diversity in the microbial mats, revealing the presence of at least five strains of bacteria. The identity of some of the strains could be resolved to the genus Thiothrix and the Flexibacter-Cytophaga-Bacteriodes phylum, and the identity of the remaining strains was to either the Helicobacter or Thiovulum group. Two of 10 sulfur-oxidizing, chemoautotrophic pure cultures of Thiobacillus spp. (syn. Thiomonas gen. nov.) demonstrated the ability to corrode calcium carbonate, suggesting that the colonization and metabolic activity of these bacteria may be enhancing cave enlargement

Analysis of karst tufa from Guangxi, China, 2003,
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Franciskovicbilinski S, Bilinski H, Barisic D, Horvatincic N, Yuan Dx,
The paper presents an analysis of characteristic karst tufa from Guangxi, China, which has not been studied before. A comparison with tufa from Dinaric Karst of Croatia is discussed in view of the C-type climate. The major mineral is calcite. Minor minerals are quartz and dolomite, depending on location. The content of calcium carbonate varies from 65% to 92%, and that of magnesium carbonate from 0.03% to 1.77%. Among other elements, the most abundant are Fe, from 0.02% to 1.50%, and Ti, from 0.15% to 0.27%. Many other trace elements (V, Cr, Mn, Ni, Cu, Zn, As, Se, Br, Rb, Sr, Y, Zr, Hg and Pb) are also present. Specific activity of radionuclides K-40, Th-232, Cs-137, Ra-226 and U-238 varies from sample to sample. Concentration of U in tufa is close to that reported for sedimentary carbonate. Low concentration Of Cs-137 indicates that this part of the world was not exposed to nuclear explosions. The concentration of Ra-226 is the highest in Mashan County. The ratio U-238/Ra-226 (0.21-0.71) in tufa from Mashan County is significantly lower than the theoretical value of 1. In 5 of the 11 studied samples, stable isotopes delta(13)C and delta(18)O were analyzed. They were dated by means of the C-14 method. One tufa sample originated in the Pleistocene and the others in the Holocene. Because all of the tufa samples contain traces of Na and K, and K < Na, the tufa from Guangxi belong to the CO2-outgassing 'N' type according to the classification of Liu and He (1994)

Carbon isotope exchange rate of DIC in karst groundwater, 2003,
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Gonfiantini R. , Zuppi G. M. ,
The kinetics of isotopic exchange between dissolved inorganic carbon (DIC) of groundwater and calcite of the matrix of karst aquifers of Cyrenaica, Libya, can, be deduced from C-13 and C-14 data. The aquifers are mostly confined, and the majority of the wells do not show any occurrence of modem recharge: in 1976-1980, in fact, the tritium content was below 1 tritium unit (TU) in most sites. Assuming that the isotopic exchange takes place through a first order reaction such as 14 C radioactive decay, it can be shown that a linear correlation occurs between lnA and ln(delta(M) - delta - epsilon(p)), where A is the C-14 activity, delta(M) and delta are the C-13 contents of matrix calcite and DIC, respectively, and epsilon(p) is the C-13 enrichment in CaCO3 precipitation. The slope of the correlation provides the half-life of the isotopic exchange process. For Cyrenaica karst groundwater, a half-life of about 11,000 years is obtained, i.e. about double that of C-14 radioactive decay. The isotopic exchange kinetics also depends on the ratio between groundwater volume and the calcite surface exposed to the exchange process. Thus, other aquifers will show different exchange half-life values. The Cretaceous chalk aquifers of the Paris Basin, France and Lagerdorf, Germany give a half-life of about 4000 years, much shorter than that of Cyrenaica, which may be due to the high porosity, i.e. to the large surface available for the isotope exchange process. The Berkshire Chalk aquifer, UK, gives a half-life of about 10,000 years. Much higher half-lives, above 20,000 years, are obtained for two sandy aquifers in Flevoland, The Netherlands, and Texas, USA, which could be explained by the low CaCO3 content of the aquifer matrix. The highest half-life value, about 40,000 years, is obtained in an artesian limestone aquifer in Florida, USA. (C) 2002 Elsevier Science B.V. All rights reserved

Deep water circulation, residence time, and chemistry in a karst complex, 2003,
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Aquilina L, Ladouche B, Doerfliger N, Bakalowicz M,
We investigated the hydrochemistry of a complex karst hydrosystem made of two carbonate units along a coastal lagoon. Ground water emerges on the lagoon floor from a submarine spring. In addition, thermal waters circulate through the limestone and mix with karst water near the lagoon shore. A distinction between the water from the two carbonate units is related to marine influences and human activities. In one of the massifs, the data show an incongruent dissolution of dolomite with time. In the other system, a slight contamination by saline fluids from the thermal reservoir has led to high calcium and magnesium concentrations. Cl-36, C-14, and H-3 data constrain the residence time of the water, and allow for the distinguishing of four circulation types: (1) shallow surface circulation (primarily above sea level) in the karstic units with short residence times (<20 years); (2) shallow subsurface circulation (approximately 0 to -50 in) below the karstic units with residence time in the order of 50 years; (3) deep circulation at depth of 700 to 1500 m in the Jurassic limestones below thick sedimentary cover, with residence time of several thousand years for a part of the water; and (4) deep circulation at a depth of similar to2500 in, which represents the thermal reservoir in the Jurassic units with residence time of similar to100,000 years. An interpretative hydrogeological framework is based on the constraints of the geochemical analyses of the deep thermal system. and by water flow from the surface to the deep parts of the carbonate formations

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