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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 effective rainfall is effective precipitation when only rainfall is involved [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 barbados (Keyword) returned 15 results for the whole karstbase:
Showing 1 to 15 of 15
The marine oxygen isotope record in Pleistocene coral, Barbados, West Indies, 1978, Fairbanks R. G. , Matthews R. K.

Doline morphology and development in Barbados, 1983, Day M. J.

230Th234U and 14C dating of a late Pleistocene stalagmite in Lobatse II Cave, Botswana, 1994, Holmgren Karin, Lauritzen Stein Erik, Possnert Goran,
A late Pleistocene stalagmite from a karst cave in southeastern Botswana has been used to compare the 14C dating method on speleothem carbonates with the 230Th234U method. An age discrepancy between the two methods indicates that at least one of the dating series does not reflect the true growth ages. The deviation is smallest in the youngest part of the stalagmite, where 21,600 U-series years correspond to 17,800 14C BP. This is in accordance with the 14C and 230Th234U-dating results on Barbados corals (Bard et al., 1990). Subsequently, the deviation increases rapidly with age, resulting in a discrepancy of 20,000 years at the 230Th234U age of 50,000 years. Whilst the 14C results exhibit a reversed order in the middle of the sequence, the 230Th234U age estimates are stratigraphically ordered. We consider the U-series data reliable and conclude that these results do indeed reflect true calender years. The 14C age estimates are probably a result of the postdepositional introduction of 14C, but may also reflect, to some extent, variations in the atmospheric 14C content. This study indicates that 14C dating of speleothem carbonate is problematic

High-resolution temporal record of Holocene ground-water chemistry; tracing links between climate and hydrology, 1996, Banner Jl, Musgrove M, Asmerom Y, Edwards Rl, Hoff Ja,
Strontium isotope analysis of precisely dated calcite growth layers in Holocene speleothems from Barbados, West Indies, reveals high-resolution temporal variations in ground-water composition and may provide a new approach to documenting the links between climate variability and fluctuations in the hydrologic cycle such as recharge rates and flow paths. The speleothems grew in a cave that developed in a fresh-water aquifer in uplifted Pleistocene reef limestones. Three periods of ground-water Sr isotope evolution are observed: 87 Sr/ 86 Sr values decreased from 6 to 4 ka, increased from 4 to 1 ka, and decreased again after 1 ka. The Sr isotope oscillations appear to record periodic variations in the relative Sr fluxes to ground water from exchangeable soil sites vs. carbonate mineral reactions, as reflected in 87 Sr/ 86 Sr values of modern Barbados ground waters. A hydrologic model that explains changes in ground-water flow routes in karst aquifers as a function of amount of rainfall recharge can account for the speleothem Sr isotope record. Independent Holocene climate records that indicate a major period of aridity at around 1.3-1.1 ka in the American tropics correspond with periodic variations in rainfall on Barbados that are predicted by this hydrologic model

Isolated carbonate platform of Caniego, Spain: A test of the latest Albian worldwide sea-level changes, 1997, Fernandezmendiola Pa, Garciamondejar J,
The upper Albian Caniego carbonate platform consists of a 20-m-thick unit of rudist- and coral-bearing limestones that crops out at the northern margin of the Mena diapir in northern Spain, The limestones were deposited on top of a slowly subsiding area, the Mena paleohigh, a diapiric-induced horst bounded by synsedimentary faults, The Caniego limestones originated in shallow warm tropical waters following a widespread marine transgression at the base of the foraminifera Rotalipora appenninica zone (ammonite Stoliczkaia dispar zone), Around the middle part of the appenninica zone the Caniego limestones underwent subaerial exposure and karst development, Fibrous calcite cements filled the bulk of the fissure-dike and dissolution cavities, Field, petrological, and geochemical data indicate that the fibrous calcites are meteoric flowstones, delta(18)O values in these cements range from -3 parts per thousand to -4.5 parts per thousand and delta(13)C values range from -7 parts per thousand to -14 parts per thousand (relative to the Peedee belemnite [PDB] standard), Thick wedges of nearshore shallow-marine siliciclastic sediments were deposited in paleotrough areas surrounding the Caniego paleohigh while the platform was subaerially exposed, The carbonate platform was drowned in early Cenomanian time and hardground-condensed facies developed during this period (Rotalipora brotzeni zone), Deeper water noncondensed marry sedimentation was reestablished in the mid-Cenomanian (Rotalipora reicheli zone), Comparison of the Iberian Caniego limestones with worldwide successions suggests a coincidence in the timing of platform formation emergence and drowning in several basins of different lithospheric plates, Nevertheless, an overall lack of coordination of sea-level histories from different basins may be related to tectonic movements of the lithospheric plates, Plate rearrangement is invoked as the primary control on relative sea-level changes and sequence development

Protactinium-231 Dating of Carbonates by Thermal Ionization Mass Spectrometry: Implications for Quaternary Climate Change, 1997, Edwards Rl, Cheng H, Murrell Mt, Goldstein Sj,
Measurement of protactinium-231 ($^{231}$Pa) in carbonates by thermal ionization mass spectroscopy yields $^{231}$Pa ages that are more than 10 times more precise than those determined by decay counting. Carbonates between 10 and 250,000 years old can now be dated with $^{231}$Pa methods. Barbados corals that have identical $^{231}$Pa and thorium-230 ($^{230}$Th) ages indicate that the timing of sea level change over parts of the last glacial cycle is consistent with the predictions of the Astronomical Theory. Two Devils Hole calcite subsamples record identical $^{231}$Pa and $^{230}$Th ages, suggesting that the chronology of this climate record is accurate

Scuba observations of standstill levels in Elba Island (ltaly) and in Marie-Galante (West Indies). A worldwide sequence?, 1999, Collinagirard J,
Scuba observations (0 to -60 m) in Provence and Corsica and new data from Elba Island (Italy) indicate the bathymetric location of eustatic erosion levels in the Mediterranean Sea. A general sketch is given (standstill levels at-ii m, -17 m, -25 m, -35 m, -45 m, -50 m/55 m, -100 m). Isotopic data suggest contemporaneity of -100 m and -55 m levels with the two slow-down phases of Holocene transgression documented in Barbados and Tahiti coring (MWP-1A and 1B). Transgression acceleration after 14 000 BP explains the conservation of these littoral morphologies. Tectonics or isostasic movements (never more than 5 m) are prooved by differences observed in different areas of the world

Estimating recharge in a tropical karst aquifer, 2000, Jones I. C. , Banner J. L. , Humphrey J. D. ,
Unique constraints on seasonal and spatial variations in recharge to the Pleistocene limestone aquifer of Barbados are obtained from the analysis of oxygen isotopic compositions of groundwater and rainwater. Conventional methods of estimating recharge are based on groundwater chloride variations, coastal groundwater discharge, and potential evapotranspiration. These methods typically yield estimates of recharge for Barbados that range from 9% to 20% of average annual rainfall, with significant uncertainties that arise from poorly constrained model input parameters. Owing to the low relief and tropical climate of Barbados, variations in rainwater and groundwater delta(18)O values are primarily influenced by the amount of rainfall, with negligible temperature or altitude effects. Composite monthly rainwater delta(18)O values are inversely related to rainfall, while groundwater delta(18)O values show little seasonal variability. Rainwater delta(18)O values are equivalent to groundwater values only at the peak of the wet season. By using mass balance, the difference between groundwater and weighted-mean rainwater delta(18)O values gives recharge values. These values are in general agreement with estimates by conventional methods (10-20%) and provide unique additional information including the following: (1) Recharge is restricted to the wettest 1-3 months of the year, and (2) there is less recharge at higher elevations. The effective shift in delta(18)O values between contemporaneous rainwater and groundwater via recharge is a useful tool for estimating temporal and spatial variability in recharge and must be considered in paleoclimatic studies where climate inferences are based on groundwater delta(18)O values preserved in the geologic record

Start of the last interglacial period at 135 ka: Evidence from a high Alpine speleothem, 2002, Spotl Christoph, Mangini Augusto, Frank Norbert, Eichstadter Rene, Burns Stephen J. ,
A detailed study of growth periods of a flowstone from Spannagel Cave in the Zillertal Alps (Austria) at [~]2500 m above sea level, a site highly sensitive to climate changes, offers unprecedented new insights into Pleistocene climate change in Central Europe. Flowstone sample SPA 52 has a high U content (to 116 ppm); analyses of this sample reveal that episodes of calcite deposition started at 204 {} 3 ka, 135 {} 1.2 ka, and 122 ka, suggesting that at these times, the mean air temperature at this high Alpine site was within 1.5 {degrees}C of the present-day condition. The beginning of growth at 135 ka corresponds to the ending of the last glaciation and is concordant with a midpoint age for the penultimate deglaciation at 135 {} 2.5 ka, as deduced from the absolutely dated oxygen isotope curve in sediments from the Bahamas, as well as with recent coral evidence from Barbados indicating a high sea level already by 135.8 {} 0.8 ka. This set of data supports evidence against Northern Hemisphere forcing of termination II, because the insolation maximum is at 127 ka

Estimating recharge thresholds in tropical karst island aquifers: Barbados, Puerto Rico and Guam, 2003, Jones I. C. , Banner J. L. ,
The hydrology and geochemistry of groundwater in tropical island aquifers, such as Barbados, Guam and Puerto Rico, are significantly influenced by tropical climatic conditions. Recharge to these aquifers is the product of regional and local climate patterns that control rainfall. Oxygen isotopes can be used to estimate the amount and timing of recharge on these islands because seasonal fluctuations of rainwater oxygen isotopic compositions are related to the amount of rainfall. The karst aquifers on Barbados, Guam and Puerto Rico have similar rainwater and groundwater oxygen isotopic compositions. Comparison of groundwater and rainwater oxygen isotopic compositions in the three aquifers indicates that: (1) recharge occurs by rapid infiltration with little evaporation prior to recharge; and (2) recharge is associated with similar monthly rainfall thresholds of 190-200 mm. These rainfall thresholds are remarkably similar for three aquifers in different geographic locations. Differences between the spatial variations of groundwater oxygen isotopic compositions on Barbados and Puerto Rico can be attributed to the more complex groundwater flow system on Puerto Rico. The surprising similarities of hydrologic conditions under which recharge will take place can be attributed to similarities in climate and geologic conditions, such as soils and limestone bedrock, that exist on the three islands. We therefore speculate that similar recharge-rainfall thresholds may be observed in other tropical karst aquifers. (C) 2003 Elsevier Science B.V. All rights reserved

Hydrogeologic and climatic influences on spatial and interannual variation of recharge to a tropical karst island aquifer, 2003, Jones I. C. , Banner J. L. ,
[1] The hydrology and geochemistry of groundwater in tropical island aquifers, such as on Barbados, are significantly influenced by tropical climatic conditions. Recharge to these aquifers is the product of regional and local climate patterns that control rainfall. Oxygen isotopes can be used to estimate the amount and timing of recharge on these islands because seasonal fluctuations of rainwater oxygen isotopic compositions are related to the amount of rainfall. This study shows that estimates of average annual recharge to the limestone aquifer on Barbados vary widely, displaying a more direct relationship to the distribution of rainfall throughout each year than to total annual rainfall. Recharge estimates are higher during years when rainfall is concentrated in the peak wet season months than during years when rainfall is more evenly distributed throughout the year. The El Nino-Southern Oscillation appears to be partially responsible for these rainfall and recharge fluctuations. Knowledge of interannual variation of recharge and processes responsible is important because recharge variation must be considered when setting groundwater management policies related to groundwater availability

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

Episodic fluid flow, hypogene and epigene karstification, and dolomitiza-tion in an accretionary prism setting, Barbados, West Indies, 2013, Machel Hans G. , Sumrall Jonathan B. , Mylroie John E.

Unusual polygenetic void and cave development in dolomitized Miocene chalks on Barbados, West Indies, 2013, Sumrall J. B. , Mylroie J. E. , Machel H. G.

Barbados provides an unusual case of polygenetic cave development within dolomitized chalks and marls of the Miocene Oceanics Group. These diagenetic processes are driven by a succession and interplay of tectonic uplift, fracturing, hypogene fluid injection, overprinting by mixing zone diagenesis, and mechanical and biological erosion in the current littoral zone. The significance of the voids and caves within the chalks on Barbados are: 1) these appear to be the first dissolution caves documented in dolomitized chalk, and 2) these features show a polygenetic origin documenting the diagenetic changes in lithology that allowed the development and preservation of these cave types.

Episodic fluid flow, hypogene and epigene karstification, and dolomitiza-tion in an accretionary prism setting, Barbados, West Indies, 2013, Machel Hans G. , Sumrall Jonathan B. , Mylroie John E.

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