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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 chandelier is large variety of gypsum flower, with branching crystal structure that may hang many meters from a cave ceiling. very rare, except in lechuguilla cave of new mexico [9].?

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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 7 results for the whole karstbase:
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

Ochtina Aragonite Cave (Western Carpathians, Slovakia): Morphology, mineralogy of the fill and genesis, 2002, Bosak P, Bella P, Cilek V, Ford Dc, Hercman H, Kadlec J, Osborne A, Pruner P,
Ochtina Aragonite Cave is a 300 m long cryptokarstic cavity with simple linear sections linked to a geometrically irregular spongework labyrinth. The metalimestones, partly metasomatically altered to ankerite and siderite, occur as isolated lenses in insoluble rocks. Oxygen-enriched meteoric water seeping along the faults caused siderite/ankerite weathering and transformation to ochres that were later removed by mechanical erosion. Corrosion was enhanced by sulphide weathering of gangue minerals and by carbon dioxide released from decomposition of siderite/ankerite. The initial phreatic speleogens, older than 780 ka, were created by dissolution in density-derived convectional cellular circulation conditions of very slow flow. Thermohaline convection cells operating in the flooded cave might also have influenced its morphology. Later vadose corrosional events have altered the original form to a large extent. Water levels have fluctuated many times during its history as the cave filled during wet periods and then slowly drained. Mn-rich loams with Ni-bearing asbolane and bimessite were formed by microbial precipitation in the ponds remaining after the floods. Allophane was produced in the acidic environment of sulphide weathering. La-Nd-phosphate and REE enriched Mn-oxide precipitated on geochemical barriers in the asbolane layers. Ochres containing about 50 wt.% of water influence the cave microclimate and the precipitation of secondary aragonite. An oldest aragonite generation is preserved as corroded relics in ceiling niches truncated by corrosional bevels. Thermal ionisation mass spectrometry and alpha counting U series dating has yielded ages of about 500-450 and 138-121 ka, indicating that there have been several episodes of deposition, occurring during Quaternary warm periods (Elsterian 1/2, Eemian). Spiral and acicular forms representing a second generation began to be deposited in Late Glacial (14 ka - Allerod) times. The youngest aragonite, frostwork, continues to be deposited today. Both of the, younger generations have similar isotopic compositions, indicating that they originated in conditions very similar, or identical, to those found at present in the cave

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

Ochtin Aragonite Cave (Slovakia): morphology, mineralogy and genesis, 2005, Bosk P. , Bella P. , Cilek V. , Ford D. C. , Hercman H. , Kadlec J. , Osborne A. , Pruner P. ,

Ochtiná Aragonite Cave is a 300 m long cryptokarstic cavity with simple linear sections linked to a geometrically irregular spongework labyrinth. The limestones, partly metasomatically altered to ankerite and siderite, occur as lenses in insoluble rocks. Oxygen-enriched meteoric water seeping along the faults caused siderite/ankerite weathering and transformation to ochres that were later removed by mechanical erosion. Corrosion was enhanced by sulphide weathering of gangue minerals and by carbon dioxide released from decomposition of siderite/ankerite. The initial phreatic speleogens, older than 780 ka, were created by dissolution in density-derived convectional cellular circulation conditions of very slow flow. Thermohaline convection cells operating in the flooded cave might also have influenced its morphology. Later vadose corrosional events have altered the original form to a large extent. Water levels have fluctuated many times during its history as the cave filled during wet periods and then slowly drained.
Mn-rich loams with Ni-bearing asbolane and birnessite were formed by microbial precipitation in the ponds remaining after the floods. Allophane was produced in the acidic environment of sulphide weathering. La-Nd-phosphate and REE enriched Mn-oxide precipitated on geochemical barriers in the asbolane layers. Ochres containing about 50 wt.% of water influence the cave microclimate and the precipitation of secondary aragonite. An oldest aragonite generation is preserved as corroded relics in ceiling niches truncated by corrosional bevels. TIMS and alpha counting U series dating has yielded ages of about 500-450 and 138-121 ka, indicating that there have been several episodes of deposition, occurring during Quaternary warm periods (Elsterian 1/2, Eemian). Spiral and acicular forms representing a second generation began to be deposited in Late Glacial (14 ka – Alleröd) times. The youngest aragonite, frostwork, continues to be deposited today. Both of the younger generations have similar isotopic compositions, indicating that they originated in conditions very similar, or identical, to those found at present in the cave.


U-series dating and taphonomy of Quaternary vertebrates from Brazilian caves, 2006, Auler As, Pilo Lb, Smart Pl, Wang X, Hoffmann D, Richards Da, Edwards Rl, Neves Wa, Cheng H,
The geochronology and taphonomy of internationally important fossil bearing cave deposits were studied, both in the semi-arid Northern Bahia area and the subtropical southeastern Lagoa Santa area of Brazil. Taphonomic analysis suggests that the processes responsible for bone accumulation in the Brazilian caves vary between sites, and taphonomic bias can therefore be significant in causing differences in faunal composition. In the Toca da Boa Vista caves the presence of single articulated skeletons, and the entrance-related distribution indicate that random penetration of animals is the main mechanism of fossil accumulation, a process that biases the assemblage to smaller species, and takes place over extended time periods. In nearby Toca dos Ossos cave transport by runoff in the cave river is predominant, and biases the fauna remains to larger more robust bones and species. Deposition probably also occurred only at times of enhanced runoff giving a more contemporaneous assemblage. Similar processes were responsible for emplacement of the copious fossil remains in the more humid Lagoa Santa area, where terrigenous fossil deposits are found intercalated by massive speleothem calcite layers. In this area runoff under a drier climate probably accounts for the sediment emplacement inside caves. In both areas the mode of emplacement implies bias in the fossil record, resulting in fossil assemblages that do not mirror surface faunas, limiting palaeoenvironmental reconstruction.Mass spectrometric U-series analysis of speleothem calcite overlaying fossil remains gives minimum ages for fossil deposition. These ages confirm the previous view that many of the deposits derive from the late glacial, but also show that much older material (some > 350,000[no-break space]yr) is also present. The habitat requirements of critical fossil species such as bats and monkeys strongly suggest that they derive from much wetter periods when forest cover was present in the currently semi-arid Northern Bahia area. Taphonomy exerts a major control on the diversity and mode of emplacement of cave fossil deposits in eastern Brazil and thus detailed sedimentological and hydrological studies coupled with a sound geochronological approach are essential in quantifying the relative importance of each taphonomic processes before faunal and palaeoecological interpretations can be attempted

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