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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. ...

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. ...

Speleology in Kazakhstan

Shakalov on 11 Jul, 2012
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 joint pattern is a group of joints which form a characteristic geometrical relationship, and which can vary considerably from one location to another within the same geologic formation.?

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Chemistry and Karst, White, William B.
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Geochemical and mineralogical fingerprints to distinguish the exploited ferruginous mineralisations of Grotta della Monaca (Calabria, Italy), Dimuccio, L.A.; Rodrigues, N.; Larocca, F.; Pratas, J.; Amado, A.M.; Batista de Carvalho, L.A.
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
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Your search for stable-isotope (Keyword) returned 75 results for the whole karstbase:
Showing 1 to 15 of 75
Paleoclimate and location of the border between Mediterranean climate region and the Saharo-Arabian Desert as revealed by speleothems from the northern Negev Desert, Israel, , Vaks A. , Barmatthews M. , Ayalon A. , Matthews A. , Frumkin A. , Dayan U. , Halicz L. , Mogilabin A. , Schilman B. ,
Speleothem bearing karstic caves of the northern Negev Desert, southern Israel, provides an ideal site for reconstructing the paleoclimate and paleo-location of the border between Mediterranean climate region and the Saharo-Arabian Desert. Major periods of speleothem deposition (representing humid periods) were determined by high resolution 230Th-U dating and corresponding studies of stable isotope composition were used to identify the source of rainfall during humid periods and the vegetation type. Major humid intervals occurred during glacials at 190-150[no-break space]ka, 76-25[no-break space]ka, 23-13[no-break space]ka and interglacials at 200-190[no-break space]ka, 137-123[no-break space]ka and 84-77[no-break space]ka. The dominant rainfall source was the Eastern Mediterranean Sea, with a possible small contribution from southern tropical sources during the interglacial periods. When the interglacial interval rainfall was of Eastern Mediterranean origin, the minimum annual rainfall was ~ 300-350[no-break space]mm; approximately twice than of the present-day. Lower minimum amounts of precipitation could have occurred during glacial periods, due to the cooler temperatures and reduced evaporation. Although during most of the humid periods the vegetation remained steppe with mixed C3 C4 vegetation, Mediterranean C3 type steppe-forest vegetation invaded southward for short periods, and the climate in the northern Negev became closer to Mediterranean type than at present. The climate was similar to present, or even more arid, during intervals when speleothem deposition did not occur: 150-144[no-break space]ka, 141-140[no-break space]ka, 117-96[no-break space]ka, 92-85[no-break space]ka, 25-23[no-break space]ka, and 13[no-break space]ka-present-day.Precipitation increase occurred in the northern Negev during the interglacial monsoonal intensity maxima at 198[no-break space]ka, 127[no-break space]ka, 83[no-break space]ka and glacial monsoonal maxima at 176[no-break space]ka, 151[no-break space]ka, 61[no-break space]ka and 33[no-break space]ka. However, during interglacial monsoonal maxima at 105[no-break space]ka and 11[no-break space]ka, the northern Negev was arid whereas during glacial monsoonal minima it was usually humid. This implies that there is not always synchroneity between monsoonal activity and humidity in the region.Oxygen isotopic values of the northern Negev speleothems are systematically lower than contemporaneous speleothems of central and northern Israel. This part is attributed to the increased rainout of the heavy isotopes by Rayleigh fractionation processes, possibly due to the farther distance from the Mediterranean coast

Identification of the origin of oreforming solutions by the use of stable isotopes, 1977, 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

Stable isotope study of karstic-related dolomitization; Jurassic rocks from the coastal plain, Israel, 1984, Buchbinder Lg, Magaritz M, Goldberg M,

STABLE ISOTOPES IN CAVE POOL SYSTEMS - CARLSBAD-CAVERN, NEW-MEXICO, USA, 1990, Ingraham N. L. , Chapman J. B. , Hess J. W. ,
The stable isotopic ratios of drip water, pool water and water vapor collected in remote areas of Carlsbad Cavern, New Mexico, were used to develop a conceptual model of the hydrologic conditions of the cave pools. When considered in terms of open and closed pool systems, the data indicate that the pools in Carlsbad Cavern appear to leak more water than they evaporate. The pools in Carlsbad Cavern range between -43 and -31% in delta-D, -7.4 and -5.9% in delta-O-18, and have EC-values of 365-710 mu-S cm(-1). The water vapor is consistently 80-82% more depleted in D than associated pool water and appears to be under direct isotopic control by the pools. Most of the drip water ranges between -51 and -44% in delta-D, between -8.0 and -6.9% in delta-O-18, and have EC-values of 310-350 mu-S cm(-1), regardless of location of collection in the cave. Drip water collected on popcorn formations (which in this case are formed by evaporation of wall seep) have stable isotopic compositions similar to local pool water; however, they have EC-value of up to 1060 mu-S cm(-1). In addition, a small, closed pool near the Lake of the Clouds has stable isotopic compositions similar to those of the Lake and elevated EC-values of up to 9500 mu-S cm(-1). The degree of stable isotopic enrichment that evaporating waters can obtain in the Cavern is limited by exchange with the water vapor which, in turn, appears to be controlled by the pools

KINETIC ENRICHMENT OF STABLE ISOTOPES IN CRYOGENIC CALCITES, 1992, Clark Id, Lauriol B,
The C-13 and O-18 contents of cryogenic calcites formed by expulsion during the freezing of bicarbonate groundwaters are examined. Samples from karst caves within the permafrost region of northern Yukon, Canada, have deltaC-13-values as high as 17.0 parts per thousand, representing the most isotopically enriched freshwater carbonates yet reported. To account for such enrichments, calcium bicarbonate solutions were frozen and sublimated under controlled laboratory conditions. The rapid rate of reaction is shown to effectively preclude isotopic equilibration during bicarbonate dehydration, resulting in a kinetic partitioning of C-13 between CO2 and CaCO3. We find a value of 31.2 1.5 parts per thousand for 1000ln13alpha(KIE)(13alpha(KIE) = 1.032), which is considerably greater than the equilibrium fractionation factor (13epsilon(CaCO3-CO2)) of 10.3 parts per thousand at 0-degrees-C. This kinetic isotope effect (KIE) represents the ratio of the absolute reaction rate constants (13k(d)/12k(d)) for the two isotopic species during the dehydration of dissolved bicarbonate. Similar results for deltaO-18-values confirm that the reaction proceeds without isotope exchange. The KIE of O-18 is determined to be 1.006 for this reaction at 0-degrees-C. These data are compared with the KIE which occurs during the reverse reaction: CO2 hydroxylation by reaction with OH- in hyperalkaline waters

STABLE ISOTOPIC STUDY OF THE GROUNDWATER OF THE MARTHA BRAE RIVER BASIN, JAMAICA, 1992, 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

MICROBIOLOGICAL ACTIVITY IN THERMOGLACIAL KARST SPRINGS, SOUTH SPITSBERGEN, 1994, Lauritzen S. E. , Bottrell S. ,
Along the Hornsund fault zone, South Spitsbergen (76-degrees-60'N), thermokarstic springs smell of H2S and display either growth of, or eject fragments of, organic slime. The temperature in individual springs varies between 4 and 15-degrees-C. Their rate of discharge is approximately 1 L s-1 to 18 m3 s-1, corresponding to a minimum temperature of 30-degrees-C within the base of the aquifer. The water, which contains a few ppm SO4(2-), 0.5 ppm S2-, and several thousand ppm NaCl, appears to be a mixture of turbid glacial meltwater and hot brine. Water chemistry and stable isotopes indicate that the salinity is not the result of simple dilution of modern seawater from the brackish zone beneath the coastal karst aquifer, but rather originates from a deep thermal brine component where concentrations and isotopic composition of various species are controlled by water-rock interaction in the source area of the brine. A value of DELTAdeltaS-34 of up to about 30 parts per thousand indicates that sulfide is a bioreduction product of sulfate. Scanning electron microscope (SEM) studies revealed bacteria and fungal hypha in the organic slime, and larger spherical particles (approximately 3.8 mum diameter) that display high concentrations of Fe and S. These findings demonstrate the presence of sulfate-reducing bacteria within the subpermafrost aquifer

ASSOCIATION OF TEPEES AND PALEOKARST IN THE LADINIAN CALCARE-ROSSO (SOUTHERN ALPS, ITALY), 1994, Mutti M. ,
The Ladinian Calcare Rosso of the Southern Alps provides a rare opportunity to examine the temporal relationships between tepees and palaeokarst. This unit comprises peritidal strata pervasively deformed into tepees, repeatedly capped by palaeokarst surfaces mantled by terra rossa. Palaeokarsts, characterized by a regional distribution across the Southern Alps, occur at the base and at the top of the unit. Local palaeokarsts, confined to this part of the platform, occur within the Calcare Rosso and strongly affected depositional facies. Tepee deformation ranges from simple antiformal structures (peritidal tepecs) to composite breccias floating in synsedimentary cements and internal sediments (senile tepees). Peritidal tepees commonly occur at the top of one peritidal cycle, in association with subaerial exposure at the cycle top, while senile tepees affect several peritidal cycles, and are always capped by a palaeokarst surface. Cements and internal sediments form up to 80% of the total rock volume of senile tepees. The paragenesis of senile tepees is extremely complex and records several, superimposed episodes of dissolution, cement precipitation (fibrous cements, laminated crusts, mega-rays) and deposition of internal sediments (marine sediment and terra rossa). Petrographical observations and stable isotope geochemistry indicate that cements associated with senile tepees precipitated in a coastal karstic environment under frequently changing conditions, ranging from marine to meteoric, and were altered soon after precipitation in the presence of either meteoric or mixed marine/meteoric waters. Stable isotope data for the cements and the host rock show the influence of meteoric water (average deltaO-18 = - 5.8 parts per thousand), while strontium isotopes (average Sr-87/Sr-86 = 0.707891) indicate that cements were precipitated and altered in the presence of marine Triassic waters. Field relationships, sedimentological associations and paragenetic sequences document that formation of senile tepees was coeval with karsting. Senile tepees formed in a karst-dominated environment in the presence of extensive meteoric water circulation, in contrast to previous interpretations that tepees formed in arid environments, under the influence of vadose diagenesis. Tepees initiated in a peritidal setting when subaerial exposure led to the formation of sheet cracks and up-buckling of strata. This porosity acted as a later conduit for either meteoric or mixed marine/meteoric fluids, when a karst system developed in association with prolonged subaerial exposure. Relative sea level variations, inducing changes in the water table, played a key role in exposing the peritidal cycles to marine, mixed marine/meteoric and meteoric diagenetic environments leading to the formation of senile tepees. The formation and preservation in the stratigraphic record of vertically stacked senile tepees implies that they formed during an overall period of transgression, punctuated by different orders of sea level variations, which allowed formation and later freezing of the cave infills

CHEMICAL EVOLUTION OF GROUNDWATER NEAR A SINKHOLE LAKE, NORTHERN FLORIDA .1. FLOW PATTERNS, AGE OF GROUNDWATER, AND INFLUENCE OF LAKE WATER LEAKAGE, 1995, Katz B. G. , Lee T. M. , Plummer L. N. , Busenberg E. ,
Leakage from sinkhole lakes significantly influences recharge to the Upper Floridan aquifer in poorly confined sediments in northern Florida. Environmental isotopes (oxygen 18, deuterium, and tritium), chlorofluorocarbons (CFCs: CFC-11, CCl3F; CFC-12, CCl2F2; and CFC-113, C2Cl3F3), and solute tracers were used to investigate groundwater flow patterns near Lake Barco, a seepage lake in a mantled karst setting in northern Florida. Stable isotope data indicated that the groundwater downgradient from the lake contained 11-67% lake water leakage, with a limit of detection of lake water in groundwater of 4.3%. The mixing fractions of lake water leakage, which passed through organic-rich sediments in the lake bottom, were directly proportional to the observed methane concentrations and increased with depth in the groundwater flow system. In aerobic groundwater upgradient from Lake Barco, CFC-modeled recharge dates ranged from 1987 near the water table to the mid 1970s for water collected at a depth of 30 m below the water table. CFC-modeled recharge dates (based on CFC-12) for anaerobic groundwater downgradient from the lake ranged from the late 1950s to the mid 1970s and were consistent with tritium data. CFC-modeled recharge dates based on CFC-11 indicated preferential microbial degradation in anoxic waters. Vertical hydraulic conductivities, calculated using CFC-12 modeled recharge dates and Darcy's law, were 0.17, 0.033, and 0.019 mid for the surficial aquifer, intermediate confining unit, and lake sediments, respectively. These conductivities agreed closely with those used in the calibration of a three-dimensional groundwater flow model for transient and steady state flow conditions

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, 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

Microorganisms as tracers in groundwater injection and recovery experiments: a review, 1997, Harvey R. W. ,
Modern day injection and recovery techniques designed to examine the transport behavior of microorganisms in groundwater have evolved from experiments conducted in the late 1800s, in which bacteria that form red or yellow pigments were used to trace flow paths through karst and fractured-rock aquifers. A number of subsequent groundwater hydrology studies employed bacteriophage that can be injected into aquifers at very high concentrations (e.g., 10(13) phage ml(-1)) and monitored through many log units of dilution to follow groundwater flow paths for great distances, particularly in karst terrain. Starting in the 1930s, microbial indicators of fecal contamination (particularly coliform bacteria and their coliphages) were employed as tracers to determine potential migration of pathogens in groundwater. Several injection and recovery experiments performed in the 1990s employed indigenous groundwater microorganisms (both cultured and uncultured) that are better able to survive under in situ conditions. Better methods for labeling native bacteria (e.g. by stable isotope labeling or inserting genetic markers, such as the ability to cause ice nucleation) are being developed that will not compromise the organisms' viability during the experimental time course

Tracing recharge from sinking streams over spatial dimensions of kilometers in a karst aquifer, 1997, 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

Environmental isotope study of the major karst springs in Damascus limestone aquifer systems: Case of the Figeh and Barada springs, 1997, 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

Stable isotope composition of F-Pb-Zn mineralization in the Valle de Tena (Spanish Central Pyrenees), 1997, As I, Recio C, Fanlo I, Fern N,

Precipitation and alteration of late Cretaceous sedimentary apatites and siderites (Leonie Trough, Bavaria, Germany), 1998, Sattler C. D. , Halbach P. ,
Late Cretaceous sedimentary siderites and fluorapatites of the iron ore deposit 'Leonie' (Bavaria, Germany) have been investigated by geochemical and mineralogical methods to define their origin. The siderites consist to more than 90 mol% of FeCO3. This elemental composition relates to an early diagenetic fresh water depositional environment. The stable isotope geochemistry of carbon and oxygen (delta(18)O: parts per thousand SMOW; delta(13)C: -12 parts per thousand PDB) also supports a siderite genesis in meteoric waters, with carbon originating from oxidation of organic matter. The chemical composition of the fluorapatites is relatively pure and shows a very low elemental substitution for calcium and phosphate. This is the result of an intense epigenetic alteration of the primary carbonate fluorapatite and, thus, cannot be related to specific source aspects. Microscopic investigations and thermodynamic calculations reveal a precursory apatite precipitation before siderite was formed. This process is thought to have removed calcium from karst waters to a level which enables siderite to be precipitated. Because of the data and observations a siderite formation in a stagnant fresh water basin is postulated, while the apatite formation probably was initiated during a connection to the open ocean (Tethys) with temporary marine ingressions. The input of iron and partly of phosphorus and fluorine into the karst basins resulted from the draining of the uplifted easterly mountains of the igneous Bohemian Massif under the influence of a humid warm climate. During the postulated marine ingressions especially phosphorus and fluorine were brought into the system whereas most of the calcium and carbonate reached the karst troughs by dissolution of the Late Jurassic Maim limestones

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