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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 natural well is (jamaican.) a vertical shaft in limestone, open to the surface and having water at the bottom; similar to a cenote [10]. synonym: (italian.) pozzo carsico.?

Checkout all 2699 terms in the KarstBase Glossary of Karst and Cave Terms

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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 oxygen-isotope (Keyword) returned 39 results for the whole karstbase:
Showing 31 to 39 of 39
Variability of Southwest Indian summer monsoon precipitation during the Bolling-Allerod, 2005, Sinha Ashish, Cannariato Kevin G. , Stott Lowell D. , Li Hong Chun, You Chen Feng, Cheng Hai, Edwards R. Lawrence, Singh Indra B. ,
We have generated a high-resolution (<20 yr) 230Th-dated stalagmite oxygen isotope record from Timta Cave in the western Himalaya in India that documents Southwest Indian summer monsoon (ISM) precipitation variations during the Bolling-Allerod interstadial from 15.2 to 11.7 ka. Compared with the glacial and Younger Dryas, ISM precipitation was enhanced during the Bolling-Allerod. ISM precipitation was apparently coupled to variations in the East Asian monsoon and North Atlantic climate on millennial and multicentennial time scales during the deglaciation. Analyses of a high growth rate interval (<2.5 yr resolution) encompassing the late Bolling-early Allerod suggest that multidecadal monsoon variability was an important aspect of ISM behavior at that time. The frequency spectrum of ISM precipitation during this time interval is similar to that of the {Delta}14C record and other ISM precipitation records during the latest Holocene. This raises the hypothesis that multidecadal climate dynamics during the late Bolling-early Allerod may have been similar to those that operated during the last several millennia, even though the boundary conditions of these two time intervals were very different

Modification and preservation of environmental signals in speleothems, 2006, Fairchild Ij, Smith Cl, Baker A, Fuller L, Spotl C, Mattey D, Mcdermott F, Eimp,
Speleothems are primarily studied in order to generate archives of climatic change and results have led to significant advances in identifying and dating major shifts in the climate system. However, the climatological meaning of many speleothem records cannot be interpreted unequivocally, this is particularly so for more subtle shifts and shorter time periods, but the use of multiple proxies and improving understanding of formation mechanisms offers a clear way forward. An explicit description of speleothem records as time series draws attention to the nature and importance of the signal filtering processes by which the weather, the seasons, and longer-term climatic and other environmental fluctuations become encoded in speleothems. We distinguish five sources of variation that influence speleothem geochemistry, i.e. atmospheric, vegetation/soil, karstic aquifer, primary speleothem crystal growth and secondary alteration, and give specific examples of their influence. The direct role of climate diminishes progressively through these five factors. We identify and review a number of processes identified in recent and current work that bear significantly on the conventional interpretation of speleothem records, for example: (1) speleothem geochemistry can vary seasonally and hence a research need is to establish the proportion of growth attributable to different seasons and whether this varies over time; (2) whereas there has traditionally been a focus on monthly mean delta O-18 data of atmospheric moisture, current work emphasizes the importance of understanding the synoptic processes that lead to characteristic isotope signals, since changing relative abundance of different weather types might control their variation on the longer-term; (3) the ecosystem and soil zone overlying the cave fundamentally imprint the carbon and trace element signals and can show characteristic variations with time; (4) new modelling on aquifer plumbing allows quantification of the effects of aquifer mixing; (5) recent work has emphasized the importance and seasonal variability Of CO2-degassing leading to calcite precipitation upflow of a depositional site on carbon isotope and trace element composition of speleothems; (6) although much is known about the chemical partitioning between water and stalagmites, variability in relation to crystal growth mechanisms and kinetics is a research frontier; (7) aragonite is susceptible to conversion to calcite with major loss of chemical information, but the controls on the rate of this process are obscure. Analytical factors are critical in generating high-resolution speleothem records. A variety of methods of trace element analysis is available, but standardization is a common problem with the most rapid methods. New stable isotope data on Irish stalagmite CC3 compares rapid laser-ablation techniques with the conventional analysis of micromilled powders and ion microprobe methods. A high degree of comparability between techniques for delta O-18 is found on the millimeter to centimeter scale, but a previously described high-amplitude oxygen isotope excursion around 8.3 ka is identified as an analytical artefact related to fractionation of the laser-analysis associated with sample cracking. High-frequency variability of not less than 0.5 parts per thousand may be an inherent feature of speleothem delta O-18 records. (c) 2005 Elsevier B.V. All rights reserved

Carbon and oxygen isotope records and paleoclimate reconstruction (140_'250'ka B.P.) from a stalagmite of Shuinan Cave, Guilin, China, 2006, Meiliang Zhang, Hai Cheng, Daoxian Yuan, Xiaoyan Zhu, Yushi Lin, Jiaming Qin, Edwards R. ,

A penultimate glacial monsoon record from Hulu Cave and two-phase glacial terminations, 2006, Cheng H, Edwards Rl, Wang Y, Kong X, Ming Y, Kelly Mj, Wang X, Gallup Cd, Liu W,
Oxygen isotope records of three stalagmites from Hulu Cave, China, extend the previous high-resolution absolute-dated Hulu Asian Monsoon record from the last to the penultimate glacial and deglacial periods. The penultimate glacial monsoon broadly follows orbitally induced insolation variations and is punctuated by at least 16 millennial-scale events. We confirm a Weak Monsoon Interval between 135.5 {} 1.0 and 129.0 {} 1.0 ka, prior to the abrupt increase in monsoon intensity at Asian Monsoon Termination II. Based on correlations with both marine ice-rafted debris and atmospheric CH4 records, we demonstrate that most of marine Termination II, the full rise in Antarctic temperature and atmospheric CO2, and much of the rise in CH4 occurred within the Weak Monsoon Interval, when the high northern latitudes were probably cold. From these relationships and similar relationships observed for Termination I, we identify a two-phase glacial termination process that was probably driven by orbital forcing in both hemispheres, affecting the atmospheric hydrological cycle, and combined with ice sheet dynamics

Large kinetic isotope effects in modern speleothems, 2006, Mickler Patrick J. , Stern Libby A. , Banner Jay L. ,
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

The co-evolution of Black Sea level and composition through the last deglaciation and its paleoclimatic significance, 2006, Major Candace O. , Goldstein Steven L. , Ryan William B. F. , Lericolais Gilles, Piotrowski Alexander M. , Hajdas Irka,
The Black Sea was an inland lake during the last ice age and its sediments are an excellent potential source of information on Eurasian climate change, showing linkages between regionally and globally recognized millennial-scale climate events of the last deglaciation. Here, we detail changes from the last glacial maximum (LGM) through the transition to an anoxic marginal sea using isotopic (strontium and oxygen) and trace element (Sr/Ca) ratios in carbonate shells, which record changing input sources and hydrologic conditions in the basin and surrounding region. Sr isotope records show two prominent peaks between ~18 and 16 ka BP cal, reflecting anomalous sedimentation associated with meltwater from disintegrating Eurasian ice sheets that brought Black Sea level to its spill point. Following a sharp drop in Sr isotope ratios back toward glacial values, two stages of inorganic calcite precipitation accompanied increasing oxygen isotope ratios and steady Sr isotope ratios. These calcite peaks are separated by an interval in which the geochemical proxies trend back toward glacial values. The observed changes reflect negative water balance and lake level decline during relatively warm periods (Bolling-Allerod and Preboreal) and increasing river input/less evaporation, resulting in higher lake levels, during the intervening cold period (the Younger Dryas). A final shift to marine values in Sr and oxygen isotope ratios at 9.4 ka BP cal corresponds to connection with the global ocean, and marks the onset of sedimentation on the Black Sea continental shelf. This date for the marine incursion is earlier than previously suggested based on the appearance of euryhaline fauna and the onset of sapropel formation in the deep basin

Stalagmite evidence for the precise timing of North Atlantic cold events during the early last glacial, 2007, Drysdale Rn, Zanchetta G, Hellstrom Jc, Fallick Ae, Mcdonald J, Cartwright I,
Evidence of millennial-scale cold events following the last interglacial are well preserved in North Atlantic marine cores, Greenland ice, and pollen records from Europe. However, their timing was previously undetermined by radiometric dating. We report the first precise radiometric ages for two such events, C23 (105.1 {} 0.9 ka to 102.6 {} 0.8 ka) and C24 (112.0 {} 0.8 ka and 108.8 {} 1.0 ka), based on stable carbon and oxygen isotope measurements on a stalagmite from Italy (CC28). In addition to providing new information on the duration of these events in southern Europe, the age data provide invaluable tuning points for the Melisey I (C24) and Montaigu (C23) pollen zones identified in western Europe. The former event is of particular significance because it represents the end of the Eemian interglacial forest phase in western Europe. The new age data will also allow fine tuning of the timing and duration of Greenland stadial 24 (equivalent to C23) in the North Greenland Ice Core Project ice core and, via a common gasage chronology, tuning of the Vostok and EPICA (European Project for Ice Coring in Antarctica) ice cores

Stalagmite stable isotope record of recent tropical cyclone events, 2007, Frappier Ab, Sahagian D, Carpenter Sj, Gonzalez La, Frappier Br,
We present a 23 yr stalagmite record (1977-2000) of oxygen isotope variation, associated with 11 tropical cyclones (TCs), from Actun Tunichil Muknal cave in central Belize. High-resolution microsampling yielded a record of monthly to weekly temporal resolution that contains abrupt decreases (negative excursions) in calcite {delta}18O values that correspond with recent TC rain events nearby. A logistic discriminant model reliably identified TC proxy signals using the measurable parameters {delta}18O and {delta}13C values, and single point changes in {delta}18O value. The logistic model correctly identified 80% of excursions as TC events and incorrectly classified only 1 of nearly 1200 nonstorm sampling points. In addition to enabling high-resolution TC frequency reconstruction, this geologic proxy also provides information about the intensity of individual TCs. A multiple regression predicted TC intensity (R2 = 0.465, p = 0.034) using sampling frequency and excursion amplitude. Consistent with previous low-resolution studies, we found that the decadal average {delta}18O value was lower during the 1990s when several TCs produced rainfall in the area, but higher during the 1980s when only one TC struck. Longer, accurately dated, high-resolution speleothem stable isotope records may be a useful new tool for paleotempestology, to clarify associations between highly variable TC activity and the dynamic range of Quaternary climate

Stable isotope variations in stalagmites from northwestern Sweden document climate and environmental changes during the early Holocene, 2007, Sundqvist H. S. , Holmgren K. , Lauritzen S. E. ,
This paper presents two early Holocene (9.6-5.9 ka BP) high-resolution stable isotope records of stalagmites from two caves in northwestern Sweden (Korallgrottan and Labyrintgrottan). Close similarities between the Swedish records and a previously presented Norwegian stalagmite oxygen isotope record emphasize the potential of Scandinavian stalagmites to provide high-resolution regional palaeoclimatic information. The stable oxygen isotope records are interpreted to reflect the temperature evolution during the early Holocene with a gradual warming from c. 9.6 ka BP, interrupted by cooler conditions at 8.5-8.0 ka BP. The results indicate that the cooler conditions were driven by two to three abrupt cold events rather than one 8.2 event' only. Except for these cold events the stalagmite oxygen isotope records show that temperatures in northwestern Sweden were warmer than today between 9.6 and 5.9 ka BP and that during this period the interval between 7.8 and 5.9 ka BP seems to have been the warmest. The high-amplitude changes in the stable carbon isotope record of Labyrintgrottan are proposed to reflect changes in local vegetation. The area above Labyrintgrottan was most likely covered by much denser vegetation than today at the time of stalagmite growth (9.5-7.5 ka BP) and was -unlike today -probably situated below the local tree limit between 9.0 and 8.0 ka BP

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