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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 base width is the width of the hydrograph as determined by a line parallel to the time axis cutting through the points where the rising limb starts and where the recession curve ends [16].?

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 geochronology (Keyword) returned 28 results for the whole karstbase:
Showing 16 to 28 of 28
Ages et modalits des incursions humaines et animales prhistoriques dans ltage Cathala de la grotte dAldne (Hrault, France). Apport des analyses sdimentologiques et gochronologiques, 2004, Guendon Jeanlouis, Ambert Paul, Quinif Yves, Baumes Bernard, Colomer Albert, Dainat Denis, Galant Philippe, Gruneisen Alain, Gruneisen Nathalie
Chronologies and means of prehistoric human and animal frequentations into Aldne cave, Cathala level (Hrault, France). Sedimentology and geochronology studies - The Aldne cave forms a long network of galleries on four levels. Only the first two of these contain prehistoric vestiges. Superior level (Bousquet storey) presents a Lower Palaeolithic stratigraphy in the porch. It contained also, in the deep areas, a thick filling of clays and speleothems with bear bones, intensively quarried during the 19th and 20th centuries for phosphate ore. These workings allowed to discover the second level (Cathala storey) and, in these news galleries, human footprints trail with sooty marks on the walls, numerous animal paw prints, hyena coprolites, scratches and nests made by bears. After study establishing mesolithic age of human footprints (8 200 130 BP, 7 790 60 BP) and anteriority of animal passages, researches were directed on sedimentological and geochronological study (U/Th dating of speleothem). First, the age of the last animal presence in the second level of Aldne was precised, between 41 500 BP to 25 000 BP. Second, means and chronologies of closing of the prehistoric entrance of Cathala storey were revealed. The actual access in these galleries is only an artificial entrance opened up for phosphate mining. It begins by a cat-flap and shafts about twenty meters high. The access used by prehistoric humans and animals is completely obstructed by a very important boulder choke with speleothems interstratified, situated in North part of Cathala gallery. The studies of this boulder choke showed three principal phases of closing of this primitive access: a first collapse of the roof during Middle Pleistocene; an important bedded rock-fragments produced by frost shattering of primitive entrance porch, which filled principal gallery during periglacial stages of the Upper Pleistocene; and a second roof collapse, during Holocene. The burnt pieces of brand left on the ground allowed to recognise the last narrow passage taken by the Mesolithic humans before this last collapse finally obstructing this entrance.

Magmatic and Hydrothermal Chronology of the Giant Rio Blanco Porphyry Copper Deposit, Central Chile: Implications of an Integrated U-Pb and 40Ar/39Ar Database, 2005, Deckart K, Clark Ah, Celso Aa, Ricardo Vr, Bertens An, Mortensen Jk, Fanning M,
The history of hypabyssal intrusion and hydrothermal activity in the northeastern and central parts of the be-hemothian (sensu Clark, 1993) Rio Blanco-Los Bronces porphyry copper-molybdenum deposit is clarified on the basis of integrated U-Pb and 40Ar/39Ar geochronology. Isotope dilution thermal ion mass spectrometry (ID-TIMS) U-Pb dates for zircon separates and ID-TIMS and sensitive high resolution ion microprobe (SHRIMP) dates for single zircon grains in pre-, syn- and late-mineralization volcanic and intrusive host rocks in the Rio Blanco, Don Luis, and Sur-Sur mining sectors provide a temporal framework for interpretation of incremental-heating and spot-fusion 40Ar/39Ar dates for, respectively, magmatic biotite and hydrothermal biotite, muscovite, and orthoclase. The ore deposit is hosted in part by 16.77 {} 0.25 to 17.20 {} 0.05 (2{sigma}) Ma andesitic volcanic strata of the Farellones Formation, but the major host rocks are units of the San Francisco batholith, including the 11.96 {} 0.40 Ma Rio Blanco granodiorite (mine terminology), the 8.40 {} 0.23 Ma Cascada granodiorite, and the 8.16 {} 0.45 Ma diorite. Hypabyssal dacitic intrusions (late porphyries) emplaced into the batholith yield 206Pb/238U ID-TIMS dates ranging from 6.32 {} 0.09 Ma (quartz monzonite porphyry), through 5.84 {} 0.03 Ma (feldspar porphyry) to 5.23 {} 0.07 Ma (Don Luis porphyry). The late-mineralization Rio Blanco dacite plug yields a SHRIMP zircon age of 4.92 {} 0.09 Ma. The 40Ar/39Ar plateau ages for phenocrystic biotites in quartz monzonite porphyry, feldspar porphyry, and Don Luis porphyry, as well as the preore diorite, range only from 5.12 {} 0.07 to 4.57 {} 0.06 Ma. All are significantly younger than the corresponding zircons and exhibit no correlation with intrusive sequence. The 40Ar/39Ar ages for hydrothermal biotite and orthoclase veins within the San Francisco batholith units fall in a narrow interval from 5.32 {} 0.27 to 4.59 {} 0.11 Ma. Hydrothermal sericites (muscovite), one associated with chalcopyrite, yielded spot-fusion ages of 4.40 {} 0.15 Ma (Rio Blanco granodiorite hosted) and 4.37 {} 0.06 Ma (Don Luis porphyry hosted). Comparison with the ID-TIMS and SHRIMP zircon ages indicates that most of the 40Ar/39Ar ages, even 95 percent plateaus, do not record initial magmatic cooling or hydrothermal alteration-mineralization events, evidence for quasipervasive reheating to at least 300{degrees}C by successive intrusions. Published Re-Os ages for two molybdenite samples range from 5.4 to 6.3 Ma and overlap extensively with the zircon U-Pb ages for the late porphyries. They imply that Cu-Mo mineralization overlapped temporally with the emplacement of, at least, quartz monzonite porphyry and feldspar porphyry units of the late porphyry suite and was, therefore, contemporaneous with the rise of dacitic melts to subvolcanic levels. Hydrothermal activity is inferred to have continued until 4.37 {} 0.06 Ma, following intrusion of the Don Luis porphyry and the early stages of emplacement of the Rio Blanco dacite plug complex. Hypogene Cu-Mo mineralization therefore probably persisted for 2 m.y. The geochronologic data do not resolve whether ore formation was continuous or episodic, but the observed crosscutting relationships between intensely altered and mineralized country rocks and less altered and mineralized late porphyry bodies support a model in which the ascent of metal-rich brines from an unexposed zone of the parental magma chamber was periodically stimulated by magma perturbation and hypabyssal intrusion

In situ U-series dating by laser-ablation multi-collector ICPMS: new prospects for Quaternary geochronology, 2005, Eggins S. M. , Griin R. , Mcculloch M. T. , Et Al.

Electron Spin Resonance (ESR) Dating In Karst Environments, 2006, Blackwell, Bonnie A. B.

Electron spin resonance (ESR) dating has been developed for many materials, including hydroxyapatite in enamel, bone, and some fish scales, aragonite and calcite in travertine, molluscs, and calcrete, and quartz from ash, which have many potential applications in karst settings. Although the complexity of the signals in some materials has hampered routine application, research is solving these problems to make the method even more widely applicable. When tested against other dating techniques, age agreement has usually been excellent. Generally, the most reliable applications seem to be tooth enamel, some mollusc species, calcite deposits, and quartz minerals. ESR dating uses signals resulting from trapped charges created by radiation in crystalline solids. Ages are calculated by comparing the accumulated dose in the dating sample with the internal and external radiation dose rates produced by natural radiation in and around the sample. For fossils and authigenic minerals, no zeroing is necessary to obtain accurate ages. In sediment which contains reworked mineral clasts, ESR can be used to date the age of the mineral grain itself if it was not zeroed during erosion. For dating the sedimentation age, however, ESR signals must have been zeroed in order to give the correct age. High pressure, heating, and in some minerals, light exposure and grinding can zero an ESR signal, but some like hydroxyapatite have very high stability at surface temperatures. For materials that absorb uranium (U) during their burial history, such as teeth, bones, or mollusc shells, the age calculation considers their U uptake by cross calibrating with U series or U/Pb dating or by assuming different uptake models. Some difficulties in calculating the external dose rate can be overcome by applying the ESR isochron method, in which the sample acts as its own dosimeter. In open-air karst environments, changes in the external dose rate due to altered sediment cover, and hence, changing cosmic dose rates, need to be modelled. For all karst environments, sedimentary water concentration and mineralogical variations with time also need to be considered. Many ESR applications are currently used in karst settings, but several more are also possible.

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

U-Pb geochronology of speleothems by MC-ICPMS, 2006, Woodhead J. , Hellstrom J. , Maas R. El Al.

UPb geochronology of speleothems by MC-ICPMS, 2006, Woodheada Jon, Hellstroma John, Maasa Roland, Drysdaleb Russell, Zanchettac Giovanni, Devined Paul, Taylor Eve

Building upon the work of Richards et al. [1998. U–Pb dating of a speleothem of Quaternary age. Geochimica et Cosmochimica Acta 62, 3683–3688], we have developed a method for precise dating of speleothems beyond the range of the U–Th technique using the U–Pb decay scheme. By coupling low-blank sample preparation procedures and multi-collector inductively coupled plasma mass spectrometry (MC-ICPMS) analytical methodologies developed for low-level Pb-isotope analysis, we find that, under ideal circumstances (radiogenic speleothems with very low common Pb), U–Pb dating of speleothems is not only possible, but also produces excellent age resolution— often comparable to or better than U–Th studies. Corrections for initial isotopic disequilibrium are necessary and exert a strong control on the achievable age uncertainty. The technique will be of immediate benefit in extending speleothem-based climate proxy records beyond _500 ka and will also find other uses, such as the dating of associated sub-fossil remains, and providing constraints on rates of landscape evolution and neo-tectonic processes. Here we present initial results for speleothems from the Nullarbor Plain, Western Australia, and the Alpi Apuane, Italy. The Nullarbor samples provide important new constraints on the development of aridity in Australia during the late Tertiary/early Quaternary, while the Apuane samples offer insights into the landscape history and uplift of that region.

Cave geology and speleogenesis over the past 65 years: role of the National Speleological Society in advancing the science, 2007, Palmer Arthur N.
The National Speleological Society was founded in 1941, near the end of a remarkable period in the history of speleogenesis. Many well-known geologists had published on the topic during the previous decade. For various reasons the NSS did not benefit from this wave of interest, and its members were faced with reconstructing the subject from a fresh beginning. The topic was developed mainly by individuals who started as cave explorers and extended that interest into science. Some of the advances over the past 65 years include new field and laboratory techniques, models of cave origin, introduction of sulfuric acid speleogenesis, coastal cave studies, recognition of microbial mediation of cave processes, geochronology and paleoclimatology, digital modeling, and growing attention toward lava caves.

Isotope geochemistry of the mafic dikes from the Vazante nonsulfide zinc deposit, Brazil, 2007, Babinski M. , Monteiro L. V. S. , Fetter A. H. , Bettencourt J. S. , Oliveir T. F.
The Vazante Group, located in the northwestern part of Minas Gerais, hosts the most important zinc mine in Brazil, the Vazante Mine, which represents a major known example of a hypogene nonsulfide zinc deposit. The main zinc ore is represented by willemite and differs substantially from other deposits of the Vazante-Paracatu region, which are sulfide-dominated zinc-lead ore. The age of the Vazante Group and the hosted mineralization is disputable. Metamorphosed mafic dikes (metabasites) that cut the metasedimentary sequence and are affected by hydrothermal processes recently were found and may shed light on the geochronology of this important geological unit. Zircon crystals recovered from the metabasites are xenocrystic grains that yield U?Pb conventional ages ranging from 2.1 to 2.4 Ga, so the basement of the Vazante Group is Paleoproterozoic or has metasedimentary rocks whose source area was Paleoproterozoic. Pb isotopes determined for titanite separated from the metabasites have common, nonradiogenic Pb compositions, which prevents determination of their crystallization age. However, the Pb signatures observed for the titanite crystals are in agreement with those determined for galena from the carbonate-hosted Zn?Pb deposits hosted by the Vazante Group, including galena from minor sulfide ore bodies of the Vazante deposit. These similarities suggest that the metalliferous fluids that affected the metabasites may have been those responsible for galena formation, which could imply a similar lead source for both nonsulfide and sulfide zinc deposits in the Vazante?Paracatu district. This common source could be related to deep-seated, basin-derived, metalliferous fluids associated with a long-lived hydrothermal system related to diagenesis and deformation of the Vazante Group during the Neoproterozoic.

Annually Laminated Speleothems: a Review, 2008, Baker A. , Smith C. L. , Jex C. , Fairchild I. J. , Genty D. And Fuller L.
This review of annually laminated speleothems firstly considers the four types of annual laminae found within speleothems: fluorescent laminae formed by annual variations in organic matter flux; visible or petrographic laminae, formed by annual variations in calcite texture or fabric; calcite-aragonite couplets; and finally trace element laminae. The methods available to confirm the annual nature, or otherwise, of lamina deposition are reviewed. We consider the use of annual laminae in chronology building, with particular relevance to palaeoclimate reconstructions. Finally, the use of annual lamina width as a palaeoclimate proxy is reviewed.

Annually Laminated Speleothems: a Review, 2008, Baker A. , Smith C. L. , Jex C. , Fairchild I. J. , Genty D. , Fuller L.

This review of annually laminated speleothems firstly considers the four types of annual laminae found within speleothems: fluorescent laminae formed by annual variations in organic matter flux; visible or petrographic laminae, formed by annual variations in calcite texture or fabric; calcite-aragonite couplets; and finally trace element laminae. The methods available to confirm the annual nature, or otherwise, of lamina deposition are reviewed. We consider the use of annual laminae in chronology building, with particular relevance to palaeoclimate reconstructions. Finally, the use of annual lamina width as a palaeoclimate proxy is reviewed.

Uplift rates defined by U-series and 14C ages of serpulid-encrusted speleothems from submerged caves near Siracusa, Sicily (Italy), 2009, Dutton Andrea, Scicchitano Giovanni, Monaco Carmelo, Desmarchelier Jolyon M. , Antonioli Fabrizio, Lambeck Kurt, Esat Tezer M. , Fifield L. Keith, Mcculloch Malcolm T. , Mortimer Graham

We have established a plausible rate of uplift near Siracusa in southeastern Sicily (Italy) over the last glacial–interglacial cycle using U-series ages of submerged speleothem calcite and 14C ages of calcite serpulid layers that encrust the speleothems during cave submergence. The precisely determined ages of these sea level benchmarks were compared with expected relative sea level position based on glacio-hydro-isostatic modeling to assess the rate of uplift in this region. When combined with the age of various late Holocene archaeological sites that have been recently described and characterized in terms of their functional position relative to sea level these data collectively define a rate of uplift ≤0.4 mm a−1 along this portion of the Sicilian coastline. These results are consistent with an age assignment of marine isotope stage (MIS) 5.3 or 5.5 for the Akradina terrace, which in turn places temporal constraints on paleoshorelines above and below this level.

High-precision 238U234U230Th disequilibrium dating of the recent past: a review, 2009, Zhao Jianxin, Yu Kefu, Feng Yuexing

Although it was demonstrated 20 years ago that mass spectrometric U–Th methods are capable of highprecision dating of young corals, the use of this approach to decipher recent environmental, climatic and archaeological records is still restricted and its potential has not yet been widely recognised. U–Th methods are typically used to determine the ages of carbonate materials such as speleothem and coral. Dating young carbonates of this sort is challenging. Their extremely low 230Th content necessitates stricter instrumental and laboratory conditions than those required for dating older samples. Moreover, analyses must be corrected for the presence of non-radiogenic 230Th, which is proportionally far more significant than in older samples. Nevertheless, 2s precisions of around _1–10 years are readily achievable for pristine coral samples dating from the last 500 years. Although the range of analytical precisions for speleothems may vary more widely depending on U concentrations and levels of nonradiogenic 230Th correction, published studies reveal 2s precisions of around _10–80 years for typical speleothems. This paper demonstrates how the U–Th method may be applied to establish the causes of recent coral mortality, to determine the recurrence interval of extreme wave events, to investigate earthquake frequency and neotectonic uplift, to reconstruct recent climatic history, and to understand settlement patterns and sociopolitical changes in Polynesia prior to European contact.

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