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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 activated charcoal, activated carbon is a granular material usually produced by the roasting of cellulose base substances, such as wood or coconut shells, in the absence of air. it has an extremely porous structure and is used in water conditioning as an adsorbent for organic matter and certain dissolved gases [6]. it is especially useful for adsorbing tracer dyes.?

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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 u-series dating (Keyword) returned 26 results for the whole karstbase:
Showing 1 to 15 of 26
U-Series Dating of Speleothems and A-Glacial Chronology for Western North America, 1979, Harmon, Russell S.

High Precision Mass Spectrometric U-Series Dating of Speleothem, with an example from a submerged Bahamian cave, 1989, Li, W. X. , Lundberg, J. , Dickin, A. P. , Ford, D. C. , Schwarcz, H. P. , Mcnutt, R. & Williams, D.

Thesis Abstract: The U-series dating and geochemistry of flowstones from the Great Orme mine, 1996, King H. K.

Application of Thermography of Karst Hydrology, 1996, Campbell C. W. Abd El Latif M. , Foster Jo. W.
Nearly 3000 km of Belize display well-developed karst that occurs dominantly on Cretaceous limestones distributed on the periphery of the Maya Mountains. Other exposed carbonates in Belize, sharing the same tropical climate and heavy rainfall, are not karsted. The Mayas represent a horst structure raised by movement of the Caribbean-North American plate boundary. In excess of 150 km of large cave passage has been mapped, often exhibiting multi-level development likely related to this regional tectonic motion. Passages are dominantly trunk conduits solutionally bored through the lower-lying limestones by integrated allogenic streams from the Mayas. Other large, independent caves and collapse chambers are also known. Limited U-series dating of speleothem gives minimum ages of 176 KaBP for cave development. The karst surfaces are dominated by disaggregated remnants of previous fluvial networks, but also contain spectacular collapse dolines. The karst aquifers appear to be solutionally open systems of relatively high porosity (>1%). Boosting of carbon dioxide levels above surface soil CO2 occurs within aquifers, perhaps due to decay of washed-in vegetation. Mean solutional erosion is estimated at 0.10-0.13 m/Ka for these karsts.

A mineralogical analysis of karst sediments and its implications to the middle-late Pleistocene climatic changes on the Tibetan Plateau, 1998, Zhang D. D. ,
The minerals in various categories of Tibetan karst sediments were divided into three groups: carbonate, iron and silicate. The carbonate minerals, including calcite, aragonite and dolomite, consist mainly of speleothem, tufa and sinter. Most of the speleothems indicates wetter and warmer periods in early and middle Pleistocene, the youngest being 194,000 years old. The second formation of carbonate mineral, tufa, implies an arid period starting 91,000 years BP. The iron minerals, goethite and hematite, are often mixed up with cave alluvial sediments that are interbedded with flowstones, and the depression sediments. They indicate strong oxidizing environments during their deposition, which is absent at present. The clay minerals, specially kaolinite, were contained in cave alluvial, flowstone and the depression sediments as well. Combined with stratigraphic study and U-series dating, the mineral analysis shows that warmer and wetter climates, which were suitable for speleothem development, probably disappeared 200 ka ago, and drier and colder climates dominated this plateau since then

Thermal ionization mass spectrometry U-series dating of a hominid site near Nanjing, China, 2001, Zhao Jian Xin, Hu Kai, Collerson Kenneth D. , Xu Han Kui,
Mass spectrometric U-series dating of speleothems from Tangshan Cave, combined with ecological and paleoclimatic evidence, indicates that Nanjing Man, a typical Homo erectus morphologically correlated with Peking Man at Zhoukoudian, should be at least 580 k.y. old, or more likely lived during the glacial oxygen isotope stage 16 ([~]620 ka). Such an age estimate, which is [~]270 ka older than previous electron spin resonance and alpha-counting U-series dates, has significant implications for the evolution of Asian H. erectus. Dentine and enamel samples from the coexisting fossil layer yield significantly younger apparent ages, that of the enamel sample being only less than one-fourth of the minimum age of Nanjing Man. This suggests that U uptake history is far more complex than existing models can handle. As a result, great care must be taken in the interpretation of electron spin resonance and U-series dates of fossil teeth

Petrographic and Geochemical Screening of Speleothems for U-series Dating: An Example from Recrystallized Speleothems from Wadi Sannur Cavern, Egypt, 2002, Railsback, L. B. , Dabous, A. A. , Osmond, J. K. , Fleisher, C. J.
Petrographic and geochemical analyses of four speleothems from Wadi Sannur Cavern in eastern Egypt show that petrography and geochemistry can provide a useful way to screen speleothems prior to dating via U-series analysis. The speleothems vary from inclusion-rich zoned calcite to clear featureless calcite. U concentrations (ranging from 0.01-2.65 ppm) and Sr concentrations (ranging from 0.00-0.11 wt%) are greater in inclusion-rich zoned calcite. U concentrations are also greater in speleothems with small (<1.2 mm wide) columnar calcite crystals than in speleothems with larger crystals. Mg concentrations in the speleothems range from 0.2 to 2.3 mol% MgCO3 and show no significant relationship to petrography at the microscopic scale. Geochemical considerations suggest that the Wadi Sannur speleothems were originally mostly aragonite, and that all four have undergone recrystallization. More generally, they suggest that coarse clear columnar calcite and large (>1.0 ppm) ranges of U concentration are warning signs of recrystallization and U loss. However, even finer grained, inclusion-rich columnar calcite may be the result of recrystallization while retaining U contents less depleted than those of associated clear calcite.

Key Largo Limestone revisited: Pleistocene shelf-edge facies, Florida Keys, USA, 2002, Multer H. G. , Gischler E. , Lundberg J. , Simmons K. R. , Shinn E. A. ,
New dates and analysis of 12 deep and 57 shallow cores allow a more detailed interpretation of the Pleistocene shelf edge of the Florida Platform as found in various facies of the Key Largo Limestone beneath the Florida Keys. In this study a three-phase evolution of the Quaternary units (Q1-Q5) of the Key Largo is presented with new subdivision of the Q5. (1) In the first phase, the Q1 and Q2 (perhaps deposited during oxygen-isotope stage 11) deep-water quartz-rich environment evolved into a shallow carbonate phase. (2) Subsequently, a Q3 (presumably corresponding to oxygen-isotope stage 9) flourishing reef and productive high-platform sediment phase developed. (3) Finally, a Q4 and Q5 (corresponding to oxygen-isotope stages 7 and 5) stabilization phase occurred with reefs and leeward productive lagoons, followed by lower sea levels presenting a sequence of younger (isotope substages 5c, 5a) shelf-margin wedges, sediment veneers and outlier reefs. The Key Largo Limestone provides an accessible model of a carbonate shelf edge with fluctuating water depth, bordering a deep seaward basin for a period of at least 300 ka. During this time, at least four onlaps/offlaps, often separated by periods of karst development with associated diagenetic alterations, took place. The story presented by this limestone not only allows a better understanding of the history of south Florida but also aids in the interpretation of similar persistent shelf-edge sites bordering deep basins in other areas

High-resolution magnetostratigraphy of speleothems from Snežna jama, Kamnik-Savinja Alps, Slovenia, 2002, Bosá, K Pavel, Hercman Helena, Mihevc Andrej, Pruner Petr

The Snežna jama Cave is located in the Kamnik-Savinja Alps, NE Slovenia, in a Raduha Ridge. The cave is a huge, more or less horizontal fossil phreatic/epiphreatic conduit. It is penetrated by vertical shafts - invasion vadose (proglacial) caves. Close to the cave entrance, there is about 3 m high wall composed of speleothems - a complex sequence of flowstone with numerous breaks in deposition, six of them are principal. The lower part of the profile (about 85 cm) contains abundant terrigenous component (terra rossa-derived clay). Stalagmites developed in several periods are completely buried by nearly horizontal younger sequences of flowstone. Continuous speleothem log was recovered from the profile in a total length of about 2.4 m. The rock column was cut to cubes in the laboratory (2x2x2 cm) and studied both by thermal demagnetisation (23 samples, 12 steps - 20 to 620 °C) and alternating field method (98 samples, 14 steps - 1 to 100 mT). Magnetic properties identified the lithological boundary. In contrast to the upper part, the lower one shows both higher magnetic susceptibility and higher remanent magnetisation. The turn point can indicate important palaeogeographical change. Magnetostratigraphic log is composed of 7 normal and 6 reverse polarised magnetozones. The age of speleothems detected by the U-series alpha-counting spectrometry falls outside the method range, i.e. over 350 ka. Uranium isotopic equilibria indicate the age over 1.2 Ma. The age of the fill is pre-Quaternary, clearly older than 1.77 Ma. The most probable age from correlation with geomagnetic polarity timescales is about 3.0 to 5.0 or 1.8 to 3.6 Ma. Both possibilities can indicate the growth rate of speleothems of about 1.1 to 1.3 m per 1 Ma. The age of speleogenesis can be compared to some of unroofed caves in the area of the Classical Karst (SW Slovenia) connected with the Messinian period. Snežna jama was uplifted to high altitudes by younger (Plio-Pleistocene) uplift of the Alpine chain.


Symposium Abstract: Coupled ESR and U-series dating of equid teeth from archaeological sites, 2003, Hoffmann R.

U-series Dating and Human Evolution, 2003, Pike A. W. G. , Pettitt P. B. ,

Cryogenic cave calcite from several Central European caves: age, carbon and oxygen isotopes and a genetic model, 2004, Zak Karel, Urban Jan, Cilek Vaclav, Hercman Helena,
Cryogenic cave calcite (CCC), formed by segregation of solutes during water freezing, was found in three Central European caves. This calcite type forms accumulations of loose calcite grains on cave floor. The calcite grains are of highly variable crystal morphology, and of sizes ranging from less than 1 mm to over 1 cm. The most typical feature is their accumulation as loose (uncemented) crystals. U-series dating indicates the formation of CCC in the studied caves during several climatic oscillations of the Weichselian (between 61 and 36 ka BP in the Chelsiowa Jama-Jaskinia Jaworznicka cave system in Poland, between 34 and 26 ka BP in the BUML Cave in the Czech Republic, and between 26 and 21 ka BP in the Stratenska Jaskyna cave system, Slovakia). At the time of CCC formation, the studied caves were lying in a periglacial zone.Detailed C and O stable isotope study of CCC samples revealed that slow water freezing under isotope equilibrium was the dominant formational process in the studied Polish and Czech caves. Significantly higher [delta]13C values of CCC in the Stratenska Jaskyna Cave indicate either water freezing in a more opened system with continuous CO2 escape (Rayleigh fractional separation), or participation of another CO2 source. The model of slow water freezing under isotope equilibrium is supported by isolated character of the caves having limited ventilation.In contrast, modern cryogenic cave calcite powders sampled directly on the ice surface of two recently iced caves in Slovakia with high ventilation showed much higher [delta]18O and [delta]13C data, similar to cryogenic calcites obtained in experimental rapid water freezing

Palaeoclimatic implications of the growth history and stable isotope ([delta]18O and [delta]13C) geochemistry of a Middle to Late Pleistocene stalagmite from central-western Italy, 2004, Drysdale Rn, Zanchetta G, Hellstrom Jc, Fallick Ae, Zhao Jx, Isola I, Bruschi G,
The age structure and stable isotope composition of a stalagmite (CC1) from an upland cave in central-western Italy were studied to investigate regional response to global climatic changes. Four growth phases are constrained by 28 thermal ionization and multi-collector inductively coupled plasma mass spectrometry Th-U ages and reveal intermittent deposition through the period between Marine Isotope Stage (MIS) 11 and 3 (~380 and ~43 kyr). Most of the growth took place between ~380 and ~280 kyr, a period punctuated briefly by a hiatus in deposition through the glacial maximum of MIS 10. Growth was terminated abruptly at 280 kyr just prior to the MIS 8 glacial maximum. With a present-day chamber temperature of 7.5 [deg]C, the timing of hiatuses close to these glacial maxima point to freezing conditions at the time. No deposition was recorded through the entirety of MIS 7 and most of MIS 6, whilst two minor growth phases occurred at ~141-125 and ~43 kyr. Growth at 141 kyr indicates temperatures >0 [deg]C at a time when MIS 6 ice volumes were close to their maximum. High stable carbon isotope ([delta]13C) values (-2.8[per mille sign] to .1[per mille sign]) throughout the stalagmite's growth reflect a persistently low input of biogenic CO2, indicating that the steep, barren and alpine-like recharge area of today has been in existence for at least the last ~380 kyr. During MIS 9, the lowest [delta]13C values occur well after maximum interglacial conditions, suggesting a lag in the development of post-glacial soils in this high-altitude karst. The stable oxygen isotope ([delta]18O) trends match the main structural features of the major climate proxy records (SPECMAP, Vostok and Devils Hole), suggesting that the [delta]18O of CC1 has responded to global-scale climate changes, whilst remarkable similarity exists between CC1 [delta]18O and regional sea-surface temperature reconstructions from North Atlantic core ODP980 and southwest Pacific marine core MD97-2120 through the most detailed part of the CC1 record, MIS 9-8. The results suggest that CC1 and other stalagmites from the cave have the potential to capture a long record of regional temperature trends, particularly in regards to the relative severity of Pleistocene glacial stages

The Sahara-East Mediterranean dust and climate connection revealed by strontium and uranium isotopes in a Jerusalem speleothem, 2004, Frumkin A, Stein M,
This paper explores the potential of Sr and U isotope systems in speleothems as tracers of eolian dust transport and hydrological conditions. The study focuses on a speleothem from Jerusalem spanning the past 220 kyr. This speleothem provides a precisely dated record of dust flux from the Sahara to the East Mediterranean. Enhanced dust flux and Terra Rossa soil development are reflected by elevated 87Sr/86Sr ratios in the speleothem (0.7082-0.7086), while lower 87Sr/86Sr ratios (~0.7078) indicate higher contribution of the local bedrock due to low dust flux and low soil accumulation. The strontium isotope system in the speleothem is a robust monitor of the Sahara monsoon-modulated climate, since dust uptake is related to development or reduction in vegetation cover of Sahara soil. The [234U/238U] activity ratios in the speleothem range between 1.12 and 1.0. The high activity values may indicate selective removal of 234U from the soil while the low values converge to the bedrock. The migration of 234U to the cave reflects mainly the regional hydrological conditions that are modulated by the North Atlantic-Mediterranean climate system. Thus, the speleothem provides a combined record of the monsoon-North Atlantic climatic systems. Long-term stability in glacial 87Sr/86Sr ratios (0.70830.0001 over the past 220 kyr) suggests an overall similarity in eolian dust sources, and uniformity in the synoptic conditions that dominate the dust storm tracks during glacial periods

The Sahara - East Mediterranean dust and climate connection revealed by strontium and uranium isotopes in a Jerusalem speleothem, 2004, Frumkin, A. , And Stein, M.
This paper explores the potential of Sr and U isotope systems in speleothems as tracers of eolian dust transport and hydrological conditions. The study focuses on a speleothem from Jerusalem spanning the past 220 kyr. This speleothem provides a precisely dated record of dust flux from the Sahara to the East Mediterranean. Enhanced dust flux and Terra Rossa soil development is reflected by elevated 87Sr/86Sr ratios in the speleothem (0.7082-6), while lower 87Sr/86Sr ratios (~0.7078) indicate higher contribution of the local bedrock due to low dust flux and low soil accumulation. The strontium isotope system in the speleothem is a robust monitor of the Sahara monsoon-modulated climate, since dust uptake is related to development or reduction in vegetation cover of Sahara soil. The [234U/238U] activity ratios in the speleothem range between 1.12 and 1.0. The high activity values may indicate selective removal of 234U from the soil while the low values converge to the bedrock. The migration of 234U to the cave reflects mainly the regional hydrological conditions that are modulated by the North Atlantic-Mediterranean climate system. Thus, the speleothem provides a combined record of the Monsoon - North Atlantic climatic systems. Long-term stability in glacial 87Sr/86Sr ratios (0.70831 over the past 220 kyr) suggests an overall similarity in eolian dust-sources, and uniformity in the synoptic conditions that dominate the dust storm tracks during glacial periods.

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