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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. ...

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That capacity, well is the rate at which a well will yield water [16].?

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Featured articles from Cave & Karst Science Journals
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 isotopes (Keyword) returned 233 results for the whole karstbase:
Showing 1 to 15 of 233
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

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

Origin of the sedimentary deposits of the Naracoorte Caves, South Australia, , Forbes Ms, Bestland Ea,
The origin of the sediments located in the Naracoorte Caves (South Australia) was investigated via the analysis of strontium isotope ratios (87Sr/86Sr), elemental geochemistry, and mineralogy. Sedimentary deposits located in Robertson, Wet, Blanche and several other chambers in Victoria Cave are all variable mixes of fine sand and coarse silts, which display similar and consistent strontium isotope ratios (0.717-0.725). This suggests that over the 400[no-break space]ka time frame that these deposits span there has been minimal variation in the source of the clastic sediments. Increased strontium concentrations for these cave sediments correspond with increasing silt content, yet there is no correlation between 87Sr/86Sr ratios and silt content. This implies that the silt-sized component of the sediments is the main contributor of strontium to the cave sediments. Comparisons of 87Sr/86Sr with regional surficial deposits show a significant correlation between the cave sediments (avg: 0.7228; n = 27), the fine silt lunettes of the Bool Lagoon area (avg: 0.7224; n = 4), the sandy A horizons of the Coonawarra Red Brown Earths (RBEs; avg: 0.726; n = 5), and Holocene age podsolic sand deposits (0.723). These data suggest that there has been substantial flux from this group of deposits to the caves, as would be expected considering prevailing winds. This relationship is further supported by a strong correlation between many trace elements, including Ti, Zr, Ce, and Y; however, variations in clay mineralogy suggest that the fine silt-dominated lunettes and Padthaway RBEs were not significant contributors to the cave deposits. Hence, the detritus entering the caves was more than likely from areas proximal to the cave entrance and was dominated by medium grain-sized materials. Major regional deposits, including the coarser-grained, calcite-rich Bridgewater Formation sands, basalts from the lower SE, Padthaway Horst granites, Gambier limestone, and metamorphics from the Adelaide geosyncline show minimal correlation in 87Sr/86Sr ratios, elemental geochemistry, and mineralogy with the cave sediments, and are discounted as significant sources. In comparison, 87Sr/86Sr ratios for the Coorong silty sands (0.717-0.724), Lower Murray sands (0.727-0.730), and the medium size silt component of the Murray-Darling River system (0.71-0.72), compare favourably with the cave sediments. This relationship is further supported by similarities in elemental chemistry and mineralogy. Thus, much of the strontium-rich silt that is now located in the Naracoorte Cave sediments likely originated from the Murray-Darling basin. Over time, this material has been transported to the SE of South Australia, where it mixed with the medium sand component of the regressive dune ridge sequence, locally derived organic matter, limestone fragments, and fossil material to produce the unique deposits that we see evident in many of the chambers of the Naracoorte Cave system today

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

Environmental isotopes in groundwater hydrology, 1980, Fontes J.

The isotopes of hydrogen and oxygen in precipitation, 1980, Gat J. R.

Guidebook on Nuclear Techniques in Hydrology. Technical Reports Series, 1983,

Les exutoires de l'aquifre karstique de la Fontaine de Vaucluse, 1985, Michelot Cl. , Mudry J.
REMARKS ABOUT THE OUTLETS OF THE LIMESTONE AQUIFER OF THE FONTAINE DE VAUCLUSE (SOUTHEASTERN FRANCE) - The Fontaine de Vaucluse is apparently the single outlet of the Vaucluse table-lands, a calcareous aquifer of more than 1000 square kilometres. The hydro-geochemical study (major ionic elements and isotopes) of the different water spots of the western boundaries of this area (springs and wells) enables one to identify the different families of water (coming from the Vaucluse table-lands or from the Comtat plain) that emerge out of the Fontaine de Vaucluse or out of other places covered with the tertiary and quaternary deposits.

Oxygen isotopes and sea level, 1986, Chappell J. , Shackleton N. J.

Caesium-137 and Caesium-134 levels in soil in a tea plantation in Turkey after the chernobyl accident, 1989, Yesin T. , Cakir N. ,
Gamma-ray scintillation spectrometry has been used to measure the 137Cs and 134Cs levels and depth distributions in soil of a tea plantation in the Eastern Black Sea region in Turkey. Soil samples were collected in November 1987. The depth distribution was found to be exponential with [alpha] = 0.16 cm-1 and the exposure rate arising therefrom is calculated as 17.46 [mu]R/h over the ground surface

Sr isotope study of vein and cave calcites from southern Israel, 1990, Avigour A, Magaritz M, Issar A, Dodson Mh,
The strontium isotope compositions of secondary calcites from the Negev, southern Israel, were compared to those of the marine carbonate host rocks, which range in age from Triassic to Eocene, in order to understand fluid source and migration through fracture systems in dominantly carbonate strata. The Sr isotopes of these calcite clusters are divided into two groups: (1) calcites with 87Sr/86Sr values greater than those of the host carbonates; and (2) calcites with 87Sr/86Sr values close to the values of the host carbonate. 1. (1) These secondary calcites were found on the main tectonic lines of the Negev (faults and fold axes) and are enriched in 87Sr (87Sr/86Sr = 0.707709-0.709151) relative to the marine carbonate country rocks (87Sr/86Sr = 0.707251-0.70755, with one exception). These calcites are associated or crossed by thin veins filled by Fe- and Mn-oxides.2. (2) Secondary calcites with 87Sr/86Sr values close to those of the marine carbonate country rocks (0.7073-0.7077) are found in karstic caves and veins, and are located in sites which are not on the major faults and fold axes. These calcites are not crossed by Fe- and Mn-oxides.The isotopic results indicate that the solutions from which the secondary minerals of the first group precipitated were not in isotopic equilibrium with the marine host rocks. The possible source of the precipitating solutions can be either surface rain descending through the fault system or ascending groundwaters from the deep Nubian aquifer (Paleozoic to Early Cretaceous in age). In both cases there would be a limited interaction with the host sandstone rock which usually is depleted in Sr. The similarity of the 87Sr/86Sr values to those of the host rocks in the second group suggests that the main source of Sr in these calcite crystals was from the dissolution of the marine carbonate country rocks by rain- and flood waters

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

Oxygen isotopes in meteoric calcite cement as indicators of continental paleoclimate., 1991, Hays P. D. , Grossman E. L.

APPLICATION OF MICROBIAL TRACERS IN GROUNDWATER STUDIES, 1991, Hotzl H. , Kass W. , Reichert B. ,
In situ tracing experiments have proved to be reliable tools to get direct information on subsurface flow direction and flow parameters. Beside dyes, salts, radioisotopes and drift bodies, microbes can be used as tracers. In several comparative experiments carried out in porous and karst aquifers by the International Association of Tracer Hydrology (ATH) the microbial markers (bacteria and bacteriophages) have shown promising results. They are especially suitable to explain and model the subsurface transport of microorganisms

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

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