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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 anomaly is the deviation from normally expected findings, especially in exploration geophysics indicating a change in subsurface environmental conditions [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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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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GSA Bulletin, 2006, Vol 118, Issue 1, p. 65-81
Large kinetic isotope effects in modern speleothems
Abstract:
The application of stable isotopes in speleothem records requires an understanding of the extent to which speleothem calcite isotopic compositions reflect the compositions of the cave waters from which they precipitate. To test for equilibrium precipitation, modern speleothem calcite was grown on glass plates, so that the carbon and oxygen isotope composition of the calcite and the water from which it precipitated could be directly compared. The plates were placed on the tops of three actively growing stalagmites that occupy a 1 m2 area in Harrison's Cave, Barbados, West Indies. Only some of the plate {delta}13C values and none of the plate {delta}18O values correspond to equilibrium values, indicating significant kinetic isotope effects during speleothem calcite growth. We investigate herein mechanisms that may account for the kinetic isotope effects. On each plate, speleothem calcite was deposited with distinct {delta}18O and {delta}13C compositions that increase progressively away from the growth axis, with up to 6.6{per thousand} 13C and 1.7{per thousand} 18O enrichments. The positive {delta}13C versus {delta}18O trends are likely a result of 18O and 13C Rayleigh-distillation enrichment in the HCO3- reservoir owing to progressive CO2 degassing and CaCO3 precipitation. The magnitude of the {delta}13C versus {delta}18O slope is likely controlled by the extent to which CO2 hydration-hydroxylation reactions buffer the oxygen isotope composition of the HCO3- reservoir during calcite precipitation. Complete oxygen isotopic buffering of the HCO3- reservoir by CO2 hydration-hydroxylation reactions will produce a vertical {delta}13C versus {delta}18O slope in calcite sampled along a growth layer. As oxygen isotope buffering of the HCO3- reservoir decreases to no buffering, the {delta}13C versus {delta}18O slope in calcite sampled along a growth layer will decrease from vertical to 0.52 at the cave temperature. In this study, modern speleothem calcite sampled along the growth layer produced a {delta}13C versus {delta}18O slope of 3.9, indicating incomplete oxygen isotope buffering of the HCO3- reservoir during calcite precipitation. Both modern and Holocene speleothem calcite from Barbados, sampled temporally along the growth axis, shows similar positive {delta}13C versus {delta}18O slopes. These results, along with the spatial variations in glass plate calcite carbon and oxygen isotope compositions, suggest that the isotopic composition of the Holocene speleothems is in part controlled by non-equilibrium isotope effects. In addition, there is a correlation between stalactite length and oxygen and carbon isotope ratios of calcite precipitated on the corresponding stalagmite and glass plate, which may be due to 13C and 18 O enrichment of the HCO3- reservoir during CO2 degassing-calcite precipitation along the overhanging stalactite. We compiled 165 published speleothem stable isotope records with a global distribution and found that most of these records show a positive covariation between {delta}13C and {delta}18O values. Speleothem stable isotope records may be influenced by kinetic isotope effects such that temperature-controlled equilibrium fractionation models alone cannot directly explain the significance of the variations in these records. Advancing the interpretation of these records requires the calibration of cave environmental conditions with the non-equilibrium isotope effects that cause {delta}13C and {delta}18O covariations in speleothems