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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. ...

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That isochrone is a line connecting water levels in observation wells for a given instant in time [16].?

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KarstBase a bibliography database in karst and cave science.

Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
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Featured articles from other Geoscience Journals
Karst environment, Culver D.C.
Mushroom Speleothems: Stromatolites That Formed in the Absence of Phototrophs, Bontognali, Tomaso R.R.; D’Angeli Ilenia M.; Tisato, Nicola; Vasconcelos, Crisogono; Bernasconi, Stefano M.; Gonzales, Esteban R. G.; De Waele, Jo
Calculating flux to predict future cave radon concentrations, Rowberry, Matt; Marti, Xavi; Frontera, Carlos; Van De Wiel, Marco; Briestensky, Milos
Microbial mediation of complex subterranean mineral structures, Tirato, Nicola; Torriano, Stefano F.F;, Monteux, Sylvain; Sauro, Francesco; De Waele, Jo; Lavagna, Maria Luisa; D’Angeli, Ilenia Maria; Chailloux, Daniel; Renda, Michel; Eglinton, Timothy I.; Bontognali, Tomaso Renzo Rezio
Evidence of a plate-wide tectonic pressure pulse provided by extensometric monitoring in the Balkan Mountains (Bulgaria), Briestensky, Milos; Rowberry, Matt; Stemberk, Josef; Stefanov, Petar; Vozar, Jozef; Sebela, Stanka; Petro, Lubomir; Bella, Pavel; Gaal, Ludovit; Ormukov, Cholponbek;
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Your search for 18o (Keyword) returned 127 results for the whole karstbase:
Showing 1 to 15 of 127
Speleothems and paleoglaciers, , Spotl Christoph, Mangini Augusto,
Ice and speleothems are widely regarded as mutually exclusive as the presence of liquid water is a fundamental prerequisite for speleothem deposition. Here we show that speleothems may form in caves overlain by a glacier, as long as the temperature in the cave is above freezing and the conduits are not completely flooded by melt water. Carbonate dissolution is accomplished via sulfide oxidation and the resultant speleothems show high [delta]13C values approaching and locally exceeding those of the parent host rock (lack of soil-derived biogenic C). The [delta]18O values reflect the isotopic composition of the melt water percolating into the karst fissure network and carry an atmospheric (temperature) signal, which is distinctly lower than those of speleothems formed during periods when soil and vegetation were present above the cave. These `subglacial' speleothems provide a means of identifying and dating the former presence of warm-based paleoglaciers and allow us to place some constraints on paleotemperature changes

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

Isotopic Composition of Precipitation, Cave Drips and Actively Forming Speleothems at Three Tasmanian Cave Sites, 1982, Goede A. , Green D. C. , Harmon R. S.

Monthly samples of precipitation and cave drips were collected from three Tasmanian cave sites along a north-south transect and their 18O/16O ratios determined. At one station D/H ratios were also measured and the relationship between delta 18O and delta D values investigated. The 18O/16O and D/H ratios of monthly precipitation show marked seasonality with values correlating strongly with mean monthly temperatures. The effect of temperature on 18O/16O ratios appears to increase as one goes southwards and is at least twice as strong at Hastings (.61 deg /oo SMOW/ deg C) as it is shown at Mole Creek (.28 deg /oo SMOW/ deg C). Irregularities in the seasonal pattern of 18O/16O change are particularly pronounced at Hastings and in the Florentine Valley and can be attributed to the amount effect. For delta 18O values > -5.5 deg /oo the combined data from the three Tasmanian stations show an amount effect of .026 deg /oo SMOW/mm. Cave drips show apparently random, non-seasonal variation in the 18O / 16O isotopic compostion but the weighted mean of the 18O/16O isotope composition of precipitation provides a good approximation to their mean 18O/16O isotopic composition. In contrast to their D/H ratios for a cave drip site in Little Trimmer Cave, Mole Creek, show a distict seasonal pattern. The 18O/16O and 13C/12C ratios have been determined for a number of actively forming speleothems. With respect to 18O/16O it is found that speleothems the three sites are being deposited under conditions approaching isotopic equilibrium. The 13C/12C ratios of these speleothems are highly variable but the generally less negative values found in Frankcombe Cave (Florentine Valley) compared with the other two sites may reflect the effects of recent clearfelling in the area.

Trace-element partition coefficients in the calcite-water system and their paleoclimatic significance in cave studies, 1983, Gascoyne M,
Speleothems (stalactites, stalagmites) formed in limestone caves have been found to contain much information on the timing and intensity of past climates, from analysis of their U, Th, 13C and 18O contents. Because the incorporation of certain trace elements (e.g., Mg, Mn and Zn) in calcite is known to be temperature-dependent, it may be possible to use variations in trace-metal content of fossil speleothems as an alternative paleotem-perature indicator. Using specially developed ion-exchange sampling techniques, analysis of trace-metal content of seepage water and associated fresh calcite deposits in caves in Vancouver Island and Jamaica shows that Mg is distributed between phases in a consistent manner within the temperature regimes of the caves (7[deg] and 23[deg]C, respectively). Average values of the distribution coefficient for Mg are respectively 0.017 and 0.045 at these temperatures. These results indicate that the Mg content of calcite varies directly with temperature and in a sufficiently pronounced manner that a 1[deg]C rise in depositional temperature of a speleothem containing 500 ppm Mg, at ~10[deg]C, would be seen as an increase of ~35ppm Mg -- a readily determinable shift. Other factors affecting Mg content of a speleothem are considered

A reconnaissance isotope study of waters in the karst of the Western Tatra mountains, 1988, Rozanski K. , Dulinski M. ,
Presented are results of isotope investigations of waters collected in the karstic area of the Western Tatra Mts. Altogether 35 groundwater samples have been analysed (tritium content, [delta]D, [delta]18O). They represent groundwaters collected on the earth surface (springs, streams, exurgences) as well as waters found in caves. Parallel, systematic isotope analyses of monthly precipitation collected at the Ornak station located in the center of the investigated area were also carried out. The results of isotope investigations fully confirm earlier suggestions that the karst system of the Western Tatra Mts consists of separate independent subsystems exhibiting weak (if any) hydraulic interconnections. Tritium data allow a semi-quantitative assessment of the mean residence time of the baseflow component in the investigated system. It is equal to at least 7/8 years. Eventual further measurements of tritium content should allow a more precise determination of this parameter. [delta]D and [delta]18O analyses of the investigated waters provide a basis for assessment of the Is/I ratio i.e. the ratio of infiltration originating from summer precipitation to the total yearly infiltration. It appears that groundwaters collected in caves exhibit on the average significantly higher D and 18O content compared to groundwaters collected on the surface. Possible reasons of this effect are discussed thoroughly in the paper

Palaeoclimate determination from cave calcite deposits, 1992, Gascoyne M,
Calcite deposits formed in limestone caves have been found to be an excellent repository of palaeoclimatic data for terrestrial environments. The very presence of a relict deposit indicates non-glacial conditions at the time of formation, and both 14C and uranium-series methods can be used to date the deposit and, hence, the age of these climatic conditions. Variations in 13C and 18O content of the calcite, in 2H and 18O content of fluid inclusions, in trace element concentrations and, more recently, in pollen assemblages trapped in the calcite, are all potentially available as synchronous palaeoclimatic indicators. Previous work has tended to concentrate mainly on abundance of deposits as a palaeoclimatic indicator for the last 300,000 years. This literature is briefly reviewed here, together with the theory and methods of analysis of the U-series and stable isotopic techniques. The combined use of U-series ages and 13C and 18O variations in cave calcites illustrates the potential for palaeoclimate determination. Previously unpublished results of stable isotopic variations in dated calcites from caves in northern England indicate the level of detail of stable isotopic variations and time resolution that can be obtained, and the complexity of interpretation that may arise. Tentative palaeoclimatic signals for the periods 90-125 ka and 170-300 ka are presented. More comprehensive studies are needed in future work, especially in view of the difficulty in obtaining suitable deposits and the ethics of cave deposits conservation

A High-Resolution Record of Holocene Climate Change in Speleothem Calcite from Cold Water Cave, Northeast Iowa, 1992, Dorale Ja, Gonzalez La, Reagan Mk, Pickett Da, Murrell Mt, Baker Rg,
High-precision uranium-thorium mass spectrometric chronology and 18O-13C isotopic analysis of speleothem calcite from Cold Water Cave in northeast Iowa have been used to chart mid-Holocene climate change. Significant shifts in [dagger]18O and [dagger]13C isotopic values coincide with well-documented Holocene vegetation changes. Temperature estimates based on 18O/16O ratios suggest that the climate warmed rapidly by about 3{degrees}C at 5900 years before present and then cooled by 4{degrees}C at 3600 years before present. Initiation of a gradual increase in [dagger]13C at 5900 years before present suggests that turnover of the forest soil biomass was slow and that equilibrium with prairie vegetation was not attained by 3600 years before present

Niveaux marins, chronologie isotopique et karstification en rpublique dominicaine, 1993, Diaz_del_olmo F. , Camara_artigas R.
The study of marine levels and the karstification of coral reefs on the Santo Domingo coast emphasizes qua-ternary dynamics linked to climatic variations and eustatic oscillations. The evolution proposed here includes the last 400 000 years (U/Th limit) and shows the importance of stages 1, 5 and 7 (interglacial stages) in the layout of coral reefs. As far as karstifiction is concerned, the differences observed between ancient and more recent times can be accounted for by a tendancy to the drying out of the intertropical morphoclimatic system.

The astronomical theory of climate and the age of the Brunhes-Matuyama magnetic reversal, 1994, Bassinot Fc, Labeyrie Ld, Vincent E, Quidelleur X, Shackleton Nj, Lancelot Y,
Below oxygen isotope stage 16, the orbitally derived time-scale developed by Shackleton et al. [1] from ODP site 677 in the equatorial Pacific differs significantly from previous ones [e.g., 2-5], yielding estimated ages for the last Earth magnetic reversals that are 5-7% older than the K/Ar values [6-8] but are in good agreement with recent Ar/Ar dating [9-11]. These results suggest that in the lower Brunhes and upper Matuyama chronozones most deep-sea climatic records retrieved so far apparently missed or misinterpreted several oscillations predicted by the astronomical theory of climate. To test this hypothesis, we studied a high-resolution oxygen isotope record from giant piston core MD900963 (Maldives area, tropical Indian Ocean) in which precession-related oscillations in [delta]18O are particularly well expressed, owing to the superimposition of a local salinity signal on the global ice volume signal [12]. Three additional precession-related cycles are observed in oxygen isotope stages 17 and 18 of core MD900963, compared to the composite curves [4,13], and stage 21 clearly presents three precession oscillations, as predicted by Shackleton et al. [1]. The precession peaks found in the [delta]18O record from core MD900963 are in excellent agreement with climatic oscillations predicted by the astronomical theory of climate. Our [delta]18O record therefore permits the development of an accurate astronomical time-scale. Based on our age model, the Brunhes-Matuyama reversal is dated at 775 10 ka, in good agreement with the age estimate of 780 ka obtained by Shackleton et al. [1] and recent radiochronological Ar/Ar datings on lavas [9-11]. We developed a new low-latitude, Upper Pleistocene [delta]18O reference record by stacking and tuning the [delta]18O records from core MD900963 and site 677 to orbital forcing functions

Rainfall-recharge relationships within a karstic terrain in the Eastern Mediterrainian semi-arid region, Israel: 18O and D characteristics, 1998, Ayalon A. , Barmatthews M. , Sass E.

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

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

Isotopic Stratigraphy of a Last Interglacial Stalagmite from Northwestern Romania: Correlation with the Deep-sea Record and Northern-latitude Speleothem, 1999, Lauritzen, S. E. , Onac, B. P.
LFG-2, a 39.5 cm tall stalagmite from northwestern Romania, has been dated by U-series a-spectrometric dating, and analyzed for stable isotope variations (d18O, d13C) along its growth axis. The sample grew all the way through oxygen isotope stage 5(a-e), and perhaps for some time into stage 4. In spite of a rather low uranium content and therefore imprecise chronology, the sample provides an interesting stable isotope record with high temporal resolution that correlates favorably with other speleothems and with the deep-sea record. Termination II is well defined in the record as a rapid shift from light (cold) to heavier (warm) d18O values, when C3 vegetation seemed to dominate. The d13C in a slow growth zone, corresponding to oxygen isotope stage 5d, as well after the stage 5/4 transition, suggests that C4 plants possibly dominated the surface environment. The d18O record also correlate quite well with the a-dated FM-2 record from northern Norway

Speleothem evidence for Holocene fluctuations of the prairie-forest ecotone, north-central USA, 1999, Denniston Rf, Gonzalez La, Baker Rg, Asmerom Y, Reagan Mk, Edwards Rl, Alexander Ec,
Carbon and oxygen isotopic trends from seven Midwestern speleothems record significant offsets in the timing of middle-Holocene vegetation change. Interactions of dry Pacific and moist Gulf of Mexico air masses maintained a sharp moisture gradient across Iowa, Minnesota, and Wisconsin such that the arrival of prairie was offset by 2000 years between caves and pollen sites located only 50 km apart. Oxygen isotopes shift concomitantly with carbon in most cases, although these changes are believed to represent increased evaporative enrichment of 18O prior to infiltration during the prairie period

A Holocene millennial-scale climatic cycle from a speleothem in Nahal Qanah Cave, Israel, 1999, Frumkin A, Carmi I, Gopher A, Ford Dc, Schwarcz Hp, Tsuk T,
Nahal Qanah Cave, located in the east Mediterranean region, has been inhabited by humans during several periods of the Holocene. These well-dated cultures are used here to establish the age of a speleothem growing over archaeological remains. d18O and d13C from a stalagmite through the last 6000 years display a 1000-2000-year cycle. Depleted d18O and d13C value correlate well with high Dead Sea levels and increased arboreal pollen, suggesting common climatic control affecting the entire region

Holocene millenial-scale climatic cycle from Nahal Qanah Cave speleothem, Israel, 1999, Frumkin, A. , Carmi, I. , Gopher, A. , Tsuk, T. , Ford, D. C. And Schwarcz, H. P.
Nahal Qanah Cave, located in the east-Mediterranean region, has been inhabited by humans during several periods of the Holocene. These well-dated cultures are used here to establish the age of a speleothem growing over archaeological remains. d18O and d13C of a stalagmite through the last 6000 years display a 1-2 thousand years cycle. Depleted d18O and d13C values correlate well with high Dead Sea levels and increased arboreal pollen, suggesting common climatic control affecting the entire region.

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