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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 viscosity is 1. the resistance of liquid to flow [16]. 2. the property of a real fluid creating shear forces between two fluid elements and giving rise to fluid friction [16]. specifically, it is the ratio of the shear stress to the rate of shear strain [6].?

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Featured articles from Cave & Karst Science Journals
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Your search for c-13 (Keyword) returned 13 results for the whole karstbase:
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

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

Hydrochemical and hydrodynamical investigations are presented to explain tufa deposition rates along the flow path of the Huanglong Ravine, located in northwestern Sichuan province, China, on an altitude of about 3400 m asl. Due to outgassing of CO2 the mainly spring-fed stream exhibits, along a valley of 3.5 km, calcite precipitation rates up to a few mm/year. We have carried out in situ experiments to measure calcite deposition rates at rimstone dams, inside of pools and in the stream-bed. Simultaneously, the downstream evolution of water chemistry was investigated at nine locations with respect to Ca2 Mg2, Na, Cl-, SO42-, and alkalinity. Temperature, pH, and conductivity were measured in situ, while total hardness, Ca-T, and alkalinity have been determined immediately after sampling, performing standard titration methods. The water turned out to be of an almost pure Ca-Mg-HCO3 type. The degassing of CO2 causes high supersaturation with respect to calcite and due to calcite precipitation the Ca2 concentration decreases from 6 . 10(-3) mole/l upstream down to 2.5 . 10(-3) mole/l at the lower course. Small rectangular shaped tablets of pure marble were mounted under different flow regimes, i.e., at the dam sites with fast water flow as well as inside pools with still water. After the substrate samples had stayed in the water for a period of a few days, the deposition rates were measured by weight increase, up to several tens of milligrams. Although there were no differences in hydrochemistry, deposition rates in fast flowing water were higher by as much as a factor of four compared to still water, indicating a strong influence of hydrodynamics. While upstream rates amounted up to 5 mm/year, lower rates of about 1 mm/year were observed downstream. Inspection of the marble substrate surfaces by EDAX and SEM (scanning electron microscope) revealed authigeneously grown calcite crystals of about 10 mu m. Their shape and habit are indicative of a chemically controlled inorganic origin. By applying a mass transfer model for calcite precipitation taking into account the reaction rates at the surface given by Plummer et al. (1978), slow conversion of CO2 into H and HCO3-, and diffusional mass transport across a diffusion boundary layer, we have calculated the deposition rates from the hydrochemistry of the corresponding locations. The calculated rates agree within a factor of two with the experimental results. Our findings confirm former conclusions with respect to fast flow conditions: reasonable rates of calcite precipitation can be estimated in reducing the PWP-rate calculated from the chemical composition of the water by a factor of about ten, thus correcting for the influence of the diffusion boundary layer

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

Aufeis of the Firth River basin, Northern Yukon Canada: Insights into permafrost hydrogeology and Karst, 1997, 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

Ancient helictites and the formation of vadose crystal silt in upper Jurassic carbonates (Southern Germany), 1998, Reinhold C. ,
Speleothems and vadose crystal silt are effective indications for karstification processes in the fossil record. Upper Jurassic limestones in Southern Germany that have undergone vadose diagenesis contain on crystal margins and tips of coarse bladed calcites numerous fibrous calcite crystals, formed by abnormal growth conditions, and internal sediment within fractures and vugs, Fibrous calcite crystals grew as crusts, in fence and mesh-like arrangements. Fibrous crystals, which have a length:width ratio of greater than 1:10, are made up of stacked subcrystals composed of an alternation of hexagonal prisms and rhombohedra, They exhibit a central to somewhat eccentric capillary. Electron probe microanalysis shows low-Mg calcite mineralogy with negligible amounts of Fe, Mn, and Sr as well as dis seminated clay and metal hydroxide impurities. Stable-isotope data show relatively C-13-enriched and O-18-depleted values (delta(13)C similar to parts per thousand PDB, delta(18)O similar to -6 parts per thousand PDB), suggesting a meteoric environment and CO2 degassing as the main process of formation, Fibrous calcite crystals form from capillary fluids that are highly supersaturated with respect to calcium carbonate, contaminated with alien mineral impurities. The abnormal growth pattern is suggested to be substrate-controlled and attributed to mineral impurities that produce numerous crystallization nuclei. Fibrous calcite crystals are comparable to helictites of the filiform type that are reported only from Quaternary caves. Nevertheless, the diagenetic sequence and oxygen isotope data suggest a Late Cretaceous to early Tertiary age for their formation. The internal sediment consists exclusively of silt-size fragments of fibrous crystals and therefore is comparable to vadose crystal silt. Crystal silt is generated by the erosion of fibrous crystals both by va dose seepage and air currents. This study is the first observation of ancient helictites and related vadose crystal silt, documenting the close relationship between pore ceiling vadose cements and the generation of crystal silt

A four-component mixing model for water in a karst terrain in south-central Indiana, USA. Using solute concentration and stable isotopes as tracers, 2001, Lee E. S. , Krothe N. C. ,
The study area lies in a highly karstified carbonate terrain in south central Indiana. Sinkholes, conduits, and caves form large secondary pathways for the subsurface flow. As a result, the discharge from a main emergence point for the subsurface flow system, the Orangeville Rise, quickly responds to the storm events and shows wide variations in flow rate, water chemistry, and stable isotopic compositions. These responses are attributed to the mixing of water in secondary pathways. In the study area, recharge occurs through the thick, mantled karst plain and the sinkhole plains, and the role of soil layer and epikarst in the recharge process is of great importance. Rain (DIC: 2 HCO3- mg/l, delta C-13 (DIC): - 7%o) soil water (DIC: 544 HCO3- mg/l, delta C-13(DIC): - 14.7%o), epikarstic water (DIC: 224 HCO3- mg/l delta C-13(DIC): - 13.6%o), and phreatic diffuse flow water (DIC: 299 HCO3- mg/l, delta C-13(DIC): - 11.8%o) generally showed unique and constant dissolved inorganic carbon (DIC) and delta C-13(DIC) values over time. Using DIC and delta C-13(DIC) as tracers, a four-component mixing model was established for the karstic flow system. By constructing the discharge hydrograph separation curves, the mixing ratio of each component, rain (10.6%), soil (3.1%), epikarstic (52.3%), and phreatic (34.0%) water, was determined for the Orangeville Rise discharge over the testing period of 104 h after the storm event of 10/4/90. Vadose water occupied 55.4% of spring discharge and this demonstrates the importance of the unsaturated zone, especially the epikarst, in the karstic flow systems. (C) 2001 Elsevier Science B.V. All rights reserved

Variation of delta C-13 in karst soil in Yaji Karst Experiment Site, Guilin, 2002, Pan G. X. , He S. Y. , Cao J. H. , Tao Y. X. , Sun Y. H. ,
This study deals with delta(13)C variation in karst soil system of Yaji Karst Experiment Site, Guilin, a typical region of humid subtropical karst formations. Samples of near ground air, plant tissue, soil and water (soil solution and karst spring) were respectively collected on site in different seasons during 1996-1999. Considerable variation of delta(13)C values are not only found with different carbon pools of soil organic carbon, soil air CO2 and soil water HCO3-, but also with the soil depths and with different seasons during a year. The delta(13)C values Of CO2 both of near ground air and soil air are lower in July than those in April by 1parts per thousand-4parts per thousand PDB. Our results indicate that the delta(13)C values of carbon in the water and air are essentially dependent on interface carbon interaction of air-plant-soil-rock-water governed by soil organic carbon and soil CO2 in the system

Carbon isotope exchange rate of DIC in karst groundwater, 2003, 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

Carbon 13 of TDIC to quantify the role of the unsaturated zone: the example of the Vaucluse karst systems (Southeastern France), 2003, Emblanch C, Zuppi Gm, Mudry J, Blavoux B, Batiot C,
The total dissolved inorganic carbon (TDIC) and C-13(TDIC) have been used as chemical and isotopic tracers to evaluate the contribution of different water components discharging at the Fontaine de Vaucluse karst spring near Avignon. At the same time they have been used to separate its flood hydrograph. Waters flowing from unsaturated zone (UZ) and saturated zone (SZ) show similar concentration in TDIC. In UZ and SZ water rock interactions do not obey to the same kinetic. The mixing rate between water coming from the UZ characterised by a short residence time and water from the SZ with a longer residence time has been evaluated in the spring discharge. In a hydrodynamic system, which is rather complex as it is open to the soil CO2 in UZ and closed to the same CO2 in the SZ, C-13(TDIC) has excellent characteristics as an environmental tracer. In order to better describe the inwardness of mass movements within the aquifer, the apparent contrasting information obtained using two different isotopes (O-18 of water molecules and C-13 of TDIC) must be combined. O-18 informs whether the hydrodynamic system acts as piston flow (PF) or follows a well mixing model (WMM). Conversely, C-13 gives more complete information on the UZ contributes to the total discharge. (C) 2003 Elsevier B.V. All rights reserved

Differences in the C-14 age, delta C-13 and delta O-18 of Holocene tufa and speleothem in the Dinaric Karst, 2003, Horvatincic N. , Bronic I. K. , Obelic B. ,
We studied Holocene speleothems and tufa samples collected in numerous caves and rivers in the Dinaric Karst of Croatia, Slovenia, Bosnia and Herzegovina, as well as Serbia and Montenegro. Differences in the formation process of tufa and speleothems are discussed in the context of their isotopic composition (C-14, C-13 and O-18), as well as the chemistry of surface water (rivers, lakes) and drip water (in caves). The physical and chemical parameters monitored in the surface water (tufa precipitation) and drip water (speleothem precipitation) show that more stable conditions accompany speleothem rather than tufa formation. This is particularly obvious in the water temperature variations (2-22degreesC in surface water and 7-12degreesC in drip water) and in saturation index variation (3-11 in surface water and 1-6 in drip water). The range of C-14 ages recorded by Holocene speleothems (similar to 12 000 yr) is wider by several thousands years than that of Holocene tufa samples (similar to 6000 yr). delta(13)C values for tufa samples range from -12parts per thousand to -6parts per thousand and for speleothem samples from -12parts per thousand to ?? per thousand reflecting higher soil carbon and/or vegetation impact on the process of tufa than on speleothem formation. The differences in delta(18)O values of tufa and speleothem samples from different areas reflect different temperature conditions and differing isotopic composition in the water. The study shows that speleothems from the Dinaric Karst can be used as global palaeoclimatic records, whereas tufa records changes in the local palaeoenvironment. (C) 2003 Elsevier Science B.V. All rights reserved

Cave air control on dripwater geochemistry, Obir Caves (Austria): Implications for speleothem deposition in dynamically ventilated caves, 2005, Spotl C. , Fairchild I. J. , Tooth A. F. ,
There are very few process studies that demonstrate the annual variation in cave environments depositing speleothems. Accordingly, we initiated a monitoring program at the Obir Caves, an Austrian dripstone cave system characterized by a seasonally changing air flow that results in a predictable pattern of high pCO(2), during summer and low pCO(2), in winter. Although similar seasonal changes in Soil pCO(2) occur, they are not directly connected with the changes in the subsurface since the dripwaters are fed from a well-mixed source showing little seasonal variation. Cold season flushing by relatively CO2-poor air enhances degassing of CO2 in the cave and leads to a high degree of supersaturation of dripwater with regard to calcite. Forced calcite deposition during the cold season also gives rise to a pronounced pattern of synchronous seasonal variations in electrical conductivity, alkalinity, pH, Ca and delta(13)C(DIC) which parallel variations recorded in delta(13)C(cave air). Chemical components unaffected by calcite precipitation (e.g., delta D,delta(18)O,SiO2,SO4) lack a seasonal signal attesting to a long residence in the karst aquifer. Modeling shows that degassing of CO2 from seepage waters results in kinetically-enhanced C isotopic fractionation, which contrasts with the equilibrium degassing shown from the Soreq cave in Israel. The Obir Caves may serve as a case example of a dripstone cave whose seepage waters (and speleothems) show intra-annual geochemical variability that is primarily due to chemical modification of the groundwater by a dynamic, bidirectional subsurface air circulation. Copyright (c) 2005 Elsevier Ltd

Dolomite formation in breccias at the Musandam Platform border, Northern Oman Mountains, United Arab Emirates, 2006, Breesch L, Swennen R, Vincent B,
The presence of dolomite breccia patches along Wadi Batha Mahani suggests large-scale fluid flow causing dolomite formation. The controls on dolomitization have been studied, using petrography and geochemistry. Dolomitization was mainly controlled by brecciation and the nearby Hagab thrust. Breccias formed as subaerial scree deposits, with clay infill from dissolved platform limestones, during Early Cretaceous emergence. Cathodoluminescence of the dolostones indicates dolomitization took place in two phases. First, fine-crystalline planar-s dolomite replaced the breccias. Later, these dolomites were recrystallized by larger nonplanar dolomites. The stable isotope trend towards depleted values (delta O-18: -2.7 parts per thousand to - 10.2 parts per thousand VPDB and delta C-13: -0.6 parts per thousand to -8.9 parts per thousand VPDB), caused by mixing dolomite types during sampling, indicates type 2 dolomites were formed by hot fluids. Microthermometry of quartz cements and karst veins, post-dating dolomites, also yielded high temperatures. Hot formation waters which ascended along the Hagab thrust are invoked to explain type 2 dolomitization, silicification and hydrothermal karstification. (C) 2006 Elsevier B.V, All rights reserved

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