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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. ...

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. ...

Speleology in Kazakhstan

Shakalov on 11 Jul, 2012
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 travertine is 1. hard calcareous mineral deposited by flowing water, that is the same as the calcareous variety of sinter and comparable to the softer tufa. the term is normally used only for deposits formed outside caves, where plants and algae cause the precipitation by extracting carbon dioxide from the water and give travertine its porous structure. travertine forms most commonly on waterfalls that build up like gour dams. famous examples include those at plitvice in croatia, dunn's river falls in jamaica, and, largest of all, band-i-amir in afghanistan [9]. 2. calcium carbonate, caco3, light in color and generally concretionary and compact, deposited from solution in ground and surface waters. extremely porous or cellular varieties are known as calcareous tufa, calcareous sinter, or spring deposit. compact banded varieties, capable of taking a polish, are called onyx marble or cave onyx [10]. 3. generally compact calcium carbonate rock formed by precipitation of soluble bicarbonates when equilibrium is lost due to changes in temperature and chemical characteristics. soft, porous variety is called calcareous tufa [20]. synonyms: (french.) travertin; (german.) kalktuff, sinter, travertin; (greek.) travertinis/asvestolithikos toffos; (italian.) travertino; (russian.) travertin; (spanish.) travertino, toba; (turkish.) traverten, sutasi; (yugoslavian.) sedra, travertin, bigar, lehnjak. related to sinter and tufa.?

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

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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
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Your search for u-series (Keyword) returned 52 results for the whole karstbase:
Showing 1 to 15 of 52
The `human revolution' in lowland tropical Southeast Asia: the antiquity and behavior of anatomically modern humans at Niah Cave (Sarawak, Borneo), , Barker G, Barton H, Bird M, Daly P, Datan I, Dykes A, Farr L, Gilbertson D, Harrisson B, Hunt C,
Recent research in Europe, Africa, and Southeast Asia suggests that we can no longer assume a direct and exclusive link between anatomically modern humans and behavioral modernity (the `human revolution'), and assume that the presence of either one implies the presence of the other: discussions of the emergence of cultural complexity have to proceed with greater scrutiny of the evidence on a site-by-site basis to establish secure associations between the archaeology present there and the hominins who created it. This paper presents one such case study: Niah Cave in Sarawak on the island of Borneo, famous for the discovery in 1958 in the West Mouth of the Great Cave of a modern human skull, the `Deep Skull,' controversially associated with radiocarbon dates of ca. 40,000 years before the present. A new chronostratigraphy has been developed through a re-investigation of the lithostratigraphy left by the earlier excavations, AMS-dating using three different comparative pre-treatments including ABOX of charcoal, and U-series using the Diffusion-Absorption model applied to fragments of bones from the Deep Skull itself. Stratigraphic reasons for earlier uncertainties about the antiquity of the skull are examined, and it is shown not to be an `intrusive' artifact. It was probably excavated from fluvial-pond-desiccation deposits that accumulated episodically in a shallow basin immediately behind the cave entrance lip, in a climate that ranged from times of comparative aridity with complete desiccation, to episodes of greater surface wetness, changes attributed to regional climatic fluctuations. Vegetation outside the cave varied significantly over time, including wet lowland forest, montane forest, savannah, and grassland. The new dates and the lithostratigraphy relate the Deep Skull to evidence of episodes of human activity that range in date from ca. 46,000 to ca. 34,000 years ago. Initial investigations of sediment scorching, pollen, palynomorphs, phytoliths, plant macrofossils, and starch grains recovered from existing exposures, and of vertebrates from the current and the earlier excavations, suggest that human foraging during these times was marked by habitat-tailored hunting technologies, the collection and processing of toxic plants for consumption, and, perhaps, the use of fire at some forest-edges. The Niah evidence demonstrates the sophisticated nature of the subsistence behavior developed by modern humans to exploit the tropical environments that they encountered in Southeast Asia, including rainforest

U-Series Dating of Speleothems and A-Glacial Chronology for Western North America, 1979, Harmon, Russell S.

Late Quaternary U-series speleothem growth record from southeastern Minnesota, 1983, Lively R. S. ,
Cyclic deposition of secondary calcium carbonate that coincides with cycles of late Pleistocene glaciation. Peak intervals of deposition occur from the present to 13,000 yr B.P., from 35,000 to 70,000 yr B.P., from 90,000 to 170,000 yr B.P., and an undivided interval from 170,000 to 350,000 yr B.P. Local climatic conditions seem to have had as much importance in determining when deposition occurred as did the major climatic cycles recorded in the marine record.--Modified journal abstract

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.

Palaeoclimate determination from cave calcite deposits, 1992, Gascoyne M,
Calcite deposits formed in limestone caves have been found to be an excellent repository of palaeoclimatic data for terrestrial environments. The very presence of a relict deposit indicates non-glacial conditions at the time of formation, and both 14C and uranium-series methods can be used to date the deposit and, hence, the age of these climatic conditions. Variations in 13C and 18O content of the calcite, in 2H and 18O content of fluid inclusions, in trace element concentrations and, more recently, in pollen assemblages trapped in the calcite, are all potentially available as synchronous palaeoclimatic indicators. Previous work has tended to concentrate mainly on abundance of deposits as a palaeoclimatic indicator for the last 300,000 years. This literature is briefly reviewed here, together with the theory and methods of analysis of the U-series and stable isotopic techniques. The combined use of U-series ages and 13C and 18O variations in cave calcites illustrates the potential for palaeoclimate determination. Previously unpublished results of stable isotopic variations in dated calcites from caves in northern England indicate the level of detail of stable isotopic variations and time resolution that can be obtained, and the complexity of interpretation that may arise. Tentative palaeoclimatic signals for the periods 90-125 ka and 170-300 ka are presented. More comprehensive studies are needed in future work, especially in view of the difficulty in obtaining suitable deposits and the ethics of cave deposits conservation

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

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

Isotopic Stratigraphy of a Last Interglacial Stalagmite from Northwestern Romania: Correlation with the Deep-sea Record and Northern-latitude Speleothem, 1999, Lauritzen, S. E. , Onac, B. P.
LFG-2, a 39.5 cm tall stalagmite from northwestern Romania, has been dated by U-series a-spectrometric dating, and analyzed for stable isotope variations (d18O, d13C) along its growth axis. The sample grew all the way through oxygen isotope stage 5(a-e), and perhaps for some time into stage 4. In spite of a rather low uranium content and therefore imprecise chronology, the sample provides an interesting stable isotope record with high temporal resolution that correlates favorably with other speleothems and with the deep-sea record. Termination II is well defined in the record as a rapid shift from light (cold) to heavier (warm) d18O values, when C3 vegetation seemed to dominate. The d13C in a slow growth zone, corresponding to oxygen isotope stage 5d, as well after the stage 5/4 transition, suggests that C4 plants possibly dominated the surface environment. The d18O record also correlate quite well with the a-dated FM-2 record from northern Norway

Speleothems and climate: a special issue of The Holocene, 1999, Lauritzen Stein Erik, Lundberg Joyce,
Speleothems (cave dripstones) are formed as a part of the meteoric water cycle and therefore vari ations in their growth rate and composition reflect environmental changes on the land surface above the cave. Since they are continental deposits, and possess a remarkably accurate dating potential, using TIMS U-series techniques, speleothems are important palaeoclimatic archives for the terrestrial environment, complementing the marine and ice-core records. The climatic proxies that can be deciphered from speleothems are growth rate, stable isotope composition (d18O, d13C), organic (humic) matter and trace element composition, as well as luminescent laminae, which may display annual rhythms. The nine papers in this special issue ofThe Holocene present the latest results in palaeoclimatic analysis from speleothems

Karst processes on Cayman Brac, a small oceanic carbonate island, PhD Thesis, 1999, Tarhulelips, Rozemarijn Frederike Antoinette

Cayman Brac is a good example of a small oceanic carbonate island which has undergone several periods of submergence and emergence since the Tertiary, resulting in the geological formations being well karstified. This study investigated several karst phenomena on the island including the occurrence and morphology of caves, the water chemistry and microclimate inside the caves, periods of speleothem growth and dissolution, and bell holes. Caves occur throughout the island at various elevations above sea level. Using elevation as a criterion, the caves were divided into Notch caves, located at, or one-two metres above, the Sangamon Notch, and Upper caves, located at varying elevations above the Notch. Analysis of the morphology, age and the relative abundance of speleothem in the caves further supports this division. The close proximity of the Notch and the Notch caves is coincidental: speleothem dating by U-series methods shows that the caves predate the Notch. They are believed to have formed between 1400 and 400 ka, whereas a late Tertiary to Early Quaternary age is assigned to the Upper caves. Speleothem on the island has suffered minor, moderate and major dissolution. Minor dissolution is due to a change in the degree of saturation of the drip water feeding the speleothem, whereas the last two are caused by flooding or condensation corrosion. Many of the speleothems in fact experienced several episodes of dissolution followed by regrowth. The latest episode appears to be caused by condensation corrosion rather than flooding. Eleven speleothems containing growth hiatuses were dated by U-series methods. The results indicate that growth cessation did not occur synchronously. Furthermore, the timing of the hiatuses during the Quaternary is not restricted to glacial or interglacial periods. Oxygen and carbon stable isotope analyses of seven of the samples reveal an apparent shift towards a drier and warmer climate around 120 ka. However, more data and further collaborative evidence is desirable. Of six samples with hiatuses, five show a bi-modal distribution of stable isotope values: before and after the hiatus. Oxygen isotope analyses of modern drip water found inter-sample variations of over 2[per thousand]. This is due to cave environmental factors such as evaporation, infiltration velocity and roof thickness. Inside the caves δ 18 O of drip water decreases with increasing distance from the entrance and thus decreasing external climatic influence. This distance-climatic effect is also reflected in the δ18 O calculated for modern calcite: -5.3, -6.5 and -7.6[per thousand] VPDB at 3, 10 and 20 m respectively. The morphology of bell holes, found only in certain Notch caves, was studied in detail. It is proposed that the bell holes are formed by condensation corrosion, probably enhanced by microbiological activity. The study represents a comprehensive and thorough analyses of karst features on a small oceanic island, and provides information useful for climatic reconstruction during the Quaternary


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

Stable isotope stratigraphy of Holocene speleothems: examples from a cave system in Rana, northern Norway, 2001, Linge H. , Lauritzen S. E. , Lundberg J. , Berstad I. M. ,
High-precision TIMS U-series dates and continuous stable oxygen and carbon isotope profiles of a 4000 year stalagmite record from Rana, northern Norway, are presented and compared with data from two other speleothems from the same cave. The dating results yield ages from 387534 to 2963 years before AD2000, with 2[sigma] errors from 0.5 to 1%. The overall growth rate is 35 mm/ka, corresponding to a temporal resolution of 29 years/mm. The stalagmite is tested for isotopic equilibrium conditions, where all `Hendy' tests, except one, indicate isotopic equilibrium or quasi equilibrium deposition. Both the stable oxygen and carbon isotope records reveal a strong and abrupt enrichment in the near-top measurements. This corresponds in time to the opening of a second cave entrance in the late 1960s, which caused changes in the cave air circulation. The stable oxygen isotope signal is enriched compared to the modern value over the last 300 years, indicating a negative response to temperature changes. Likewise, the stable carbon isotope record is enriched in this period. However, both of the stable isotope records are shown to be significantly enriched compared to the isotope ranges displayed by other stalagmites in the same cave, and this questions the reliability of the proxy records derived from the presented stalagmite. Still, a general good correspondence of large scale fluctuations is found between the three stable oxygen isotope records from this cave. The stable carbon isotope records show large variations within the cave and are believed to be governed by soil-zone conditions, percolation pathways and possibly driprates

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.

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