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Enviroscan Ukrainian Institute of Speleology and Karstology

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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 artificial discharge is the discharge of ground water by pumping wells [16].?

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

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Browse Speleogenesis Issues:

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 uranium (Keyword) returned 87 results for the whole karstbase:
Showing 16 to 30 of 87
Palaeoclimate determination from cave calcite deposits, 1992,
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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

A High-Resolution Record of Holocene Climate Change in Speleothem Calcite from Cold Water Cave, Northeast Iowa, 1992,
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Dorale Ja, Gonzalez La, Reagan Mk, Pickett Da, Murrell Mt, Baker Rg,
High-precision uranium-thorium mass spectrometric chronology and 18O-13C isotopic analysis of speleothem calcite from Cold Water Cave in northeast Iowa have been used to chart mid-Holocene climate change. Significant shifts in [dagger]18O and [dagger]13C isotopic values coincide with well-documented Holocene vegetation changes. Temperature estimates based on 18O/16O ratios suggest that the climate warmed rapidly by about 3{degrees}C at 5900 years before present and then cooled by 4{degrees}C at 3600 years before present. Initiation of a gradual increase in [dagger]13C at 5900 years before present suggests that turnover of the forest soil biomass was slow and that equilibrium with prairie vegetation was not attained by 3600 years before present

Uranium-series Disequilibrium: Applications to Earth, Marine Environmental Sciences, 1992,
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Ivanovich M. , Harmon R. S.

Uranium-series dating of the draining of an aquifer: the example of Wind Cave, Black Hills, South Dakota., 1993,
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Ford D. C. , Lundberg J. , Palmer A. N. Et Al.

230Th dating of the speleothems from the ''Grotta del Fiume-Grotta Grande del Vento'' karst system in Frasassi (Ancona, Italy) and paleoenvironmental implications., 1994,
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Taddeucci Adriano, Tuccimei Paola, Voltaggio Mario
Chronological measurements have been carried out on speleothems from the Grotta del Fiume-Grotta Grande del Vento karst system in Frasassi (Ancona, Italy) by means of the 230Th radiometric method in order to date hypogean karst levels and related geological events. Higher levels were found to be older than the lower ones according to standstills and sinkings of the water table. The dated speleothems from the first and second level formed less than 10,000 years ago; the minimum ages of the third and fifth levels, which are respectively 130,000 and 200,000 years old, were correlated to climatic events. Dating different portions of a speleothem allows the measurements of the radial and vertical accretion rates and their variation over time. Such data together with the 234U/238U activity ratio and the uranium content of the speleothems have been correlated with the climatic variations connected to the glacial cycles. The same data have been used to fit a hydrogeological model.

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Kimberley M. M. ,
Ironstone is any chemical sedimentary rock with > 15% Fe. An iron formation is a stratigraphic unit which is composed largely of ironstone. The solutes which have precipitated to become ironstone have dissolved from the Earth's surface, from the upper crust, e.g. the basaltic layer of oceanic crust, or from deeper within the Earth. Genetic modellers generally choose between surficial weathering, e.g. soil formation, and hydrothermal fluids which have convected through the upper kilometre of oceanic crust. Most genetic modellers attribute cherty laminated iron formations to hydrothermal convection and noncherty oolitic iron formations to surficial weathering. However, both types of iron formations are attributable to the exhalation of fluids from a source region too deep for convection of seawater. Evidence for a deep source of ferriferous fluids comes from a comparison of ancient ironstone with modern ferriferous sediment in coastal Venezuela. A deep-source origin for ironstone has wide-ranging implications for the origins of other chemical sedimentary ores, e.g. phosphorite, manganostone, bedded magnesite, sedimentary uranium ore, various karst-filling ores, and even petroleum. Preliminary study of a modern oolitic iron deposit described herein suggests that the source of iron and silica to iron formations may have been even deeper than envisioned within most hydrothermal convection models

Geomagnetic palaeosecular variation recorded in North And Central American speleothems, PhD thesis, 1995,
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Lean, C. M. B.

The aim of this project was to collect samples of stalagmites from Northern and Central America in order to produce records of the palaeosecular variation of the earth's magnetic field. Two stalagmites were sampled from Western Canada and ten from Mexico and Guatemala which could be compared with contemporaneous stalagmite records from these areas (Latham, 1981; Latham et al, 1982; 1986; 1987; 1989).
The stalagmites were generally weakly magnetised but remanence directions were stable upon stepwise thermal and alternating-field demagnetisation. Consistency in directions recorded between central and corresponding lateral sub-samples within two stalagmites (MSC2 from Canada and CP1 from Guatemala) inferred that any depositional errors caused by surface effects were less than the measurement errors. Grain size analysis showed the presence of a fine-grained magnetic fraction (0.01 - 0.1?:m) sourced from the cave drip-waters (either by direct deposition or by chemical precipitation) and a coarser magnetic fraction (0.01 - >10?:m) sourced from the flood-borne detritus. The latter source was dominant in stalagmites which were regularly inundated with water. The type of magnetic mineral present was determined by the geology of the catchment area; magnetite dominated in the Vancouver Island stalagmites, titanomagnetite in the Mexican stalagmites and haematite in the Guatemalan stalagmite.
Uranium-series dating of samples was hindered by the young ages of many of the samples, by low uranium concentrations and by the presence of allogenic thorium. If significant amounts of allogenic thorium were present, a sample age could be calculated based on an estimate of the initial thorium ratio ([230Th/232Th]0). Analysis of samples from Sumidero Recuerdo in Mexico, however, suggested that this ratio is not constant with time and may vary by a factor of two over approximately 1700 years. Due to these imprecisions many dates were out of stratigraphic sequence and age estimates were made assuming constant growth rates, except where growth had ceased for a finite length of time.
Records of sequential change of palaeomagnetic direction were obtained from the Mexican stalagmite SSJ3 and the Canadian stalagmite MSC2. The reliability of the latter record was confirmed by comparison with another Canadian stalagmite record (Latham et al, 1987) and contemporaneous lacustrine records. Other records were disappointing due to poor temporal resolution; each sub-sample represented a period of approximately 1000 years in Mexican stalagmites SSJ2 and SSJ4. Such slow growth rates are insufficient for the resolution of secular variation features with periods of less than 2000 years and are only suitable to gain information about the nature of long-term secular variations, for example the far-sided virtual geomagnetic poles and low inclinations predominant throughout the Holocene in Southern Mexico.
The existence of matching contemporaneous stalagmite records of secular variation together with the demonstrated lack of depositional inclination errors is encouraging, despite the sometimes "hit or miss" aspects of sample selection. Nevertheless it has been proved that speleothem records have the potential to complement the existing archaeomagnetic, lava and lacustrine data.

Karst et mines en France et en Europe : gtes, grottes-mines et gotechnique, 1996,
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Nicod, J.
Many ores have been extracted in the karst areas since the proto-historic times. The ores have been trapped in the paleokarsts, according to various processes whose origin is still much debated. Certain metal-rich minerals have been excavated in caves or "mine-caves". Many polymetallic ores in paleokarstic deposits were in exploitation in SW Sardinia, Sierra of Carthagena, Montagne Noire, Peak District, and Upper Silesia... The mercury mines of Idrija (Slovenia) and the uranium deposits of Tyuya Muyun (Kirgizia) are of particular interest. Recent studies have clearly shown the historic importance of numerous pockets of pisolitic iron (Siderolithic, Bohnerz) in the European steel metallurgy, since the Celts and Romans and up to the middle of the 19th century. The siderite ores raise special problems. Most bauxite deposits were found in karstic pockets and paleo-poljes (mediterranean type of bauxites). The studies of the old mines give a better insight into paleokarsts. Both the ancient and modern mines have created artificial karsts, and raise many geotechnical and environmental problems.

Dated co-occurrence of Homo erectus and Gigantopithecus from Tham Khuyen Cave, Vietnam, 1996,
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Ciochon R, Long Vt, Larick R, Gonzalez L, Grun R, Devos J, Yonge C, Taylor L, Yoshida H, Reagan M,
Tham Khuyen Cave (Lang Son Province, northern Vietnam) is one of the more significant sites to yield fossil vertebrates In east Asia, During the mid-1960s, excavation in a suite of deposits produced important hominoid dental remains of middle Pleistocene age, We undertake more rigorous analyses of these sediments to understand the fluvial dynamics of Pleistocene cave infilling as they determine how skeletal elements accumulate within Tham Khuyen and other east Asian sites, Uranium/thorium series analysis of speleothems brackets the Pleistocene chronology for breaching, infilling, and exhuming the regional paleokarst, Clast analysis indicates sedimentary constituents, Including hominoid teeth and cranial fragments, accumulated from very short distances and under low fluvial energy, Electron spin resonance analysis of vertebrate tooth enamel and sediments shows that the main fossil-bearing suite (S1-S3) was deposited about 475 thousand years ago, Among the hominoid teeth excavated from S1-S3, some represent Homo erectus and Gigantopithecus blacki, Criteria are defined to differentiate these teeth from more numerous Pongo pygmaeus elements, The dated cooccurrence of Homo erectus and Gigantopithecus blacki at Tham Khuyen helps to establish the long co-existence of these two species throughout east Asia during the Early and Middle Pleistocene

Large-basin groundwater circulation and paleo-reconstruction of circulation leading to uranium mineralization in Grand Canyon breccia pipes, Arisona., 1996,
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Huntoon P. W.

Mineralogy of speleothems from caves in the Padurea Craiului Mountains and their palaeoclimatic significance, PhD thesis, 1996,
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Onac, B. P.

The thesis comprises an introductory section, which provides the reader with the basic geologic, tectonic and speleologic setting of the study area in the karst of Padurea Craiului Mountains and is then divided into a mineralogical/crystallographical study and a geochronological study. The mineralogical and crystallographical investigations were based on traditional and modern methods of laboratory techniques (X-ray, thermal, infra-red, scanning electron microscope and thermal ionisation mass-spectrometric analysis) and have given several new aspects concerning the morphology and origin of cave speleothems (for example, anthodites, oulopholites, fungites). Following detailed investigations on some moonmilk speleothems, a new classification system has been proposed. The results of this first part of the thesis lead into a discussion of the conditions of formations of the studied cave minerals and their morphology.
The second part (geochronology) is dedicated to speleothem dating and contains details of the 230Th/234U chronometer and its application. The various sampling sites (caves) are presented, as well as a list of uranium-series dates. Although there are relatively few data (65), a discussion of the distribution of the ages in time and with respect to Pleistocene climate has been undertaken. It is reported that the speleothems from the Padurea Craiului Mountains display less pronounced growth intervals than those from north-western Europe.
The thesis also examines the use of caves (via speleothem dating) to obtain rates of landscape evolution. The maximum average erosion rates for the Crisul Repede basin are in the range, 0.43-046 m/1000 years. These rates represent both glacial and interglacial conditions, and compare well with rates determined from other countries. A list of minerals which form cave speleolhems is given in an Appendix. The list was compiled from the literature and updated with the author's investigations. It includes the mineral name, composition, crystal system and class, and frequency.

Palaeosecular variation observed in speleothems from western China and northern Spain, PhD thesis, 1996,
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Openshaw, S. J.

This study has produced records of the palaeosecular variation (PSV) of the earth's magnetic field from Speleothems from China and Spain. The ultimate aim of this project was to produce contemporaneous PSV records which would show that Speleothems accurately record ambient geomagnetic field behaviour. From Sichuan Province, China, five Speleothems were collected of which four were studied for their records of PSV. Eight Spanish Speleothems from the Cantabrian coast were collected but their weak magnetisation allowed only one record of PSV to be produced.
All speleothem sub-samples were weakly magnetised and had, on average, initial intensities of <100 x 10-8 Am2kg-1. Despite this, the majority of sub-samples were stable during stepwise alternating-field and thermal demagnetisation and each displayed a single component of magnetisation after removal of any secondary overprints. Rock magnetic experiments were hampered by low mineral concentrations but suggested that the remanences of each speleothem were carried by a mixture of multi and single-domain (titano-) magnetite and also by haematite present in significant quantities. The primary method of remanence acquisition appeared to be a depositional remanence sourced from flooding. This was corroborated by a linear relationship between sub-sample intensities and weight % acid insoluble detritus.
A selection of sub-samples from each speleothem were dated using uranium-thorium disequilibrium and alpha spectrometry. For the majority of sub-samples the low concentrations of uranium, high levels of detrital contamination and initially low chemical yields raised the associated dating inaccuracies above the quoted level for alpha spectrometry of 5-10%. Two Spanish Speleothems had high uranium concentrations and little, or no, detrital contamination. Percent age errors of these Speleothems ranged from 1 to 6%. Comprehensive experiments on the efficiencies of three electrodeposition methods were also undertaken. The most efficient method was found to be a modified version of the Hallstadius method (Hallstadius, 1984), which consistently achieved chemical yields between 40 and 90% for uranium and thorium.
In order to correct more analytically for the presence of detrital contamination, the leachate/leachate method of Schwarcz and Latham (1989) was tested. The maximum likelihood estimation data treatment technique (Ludwig and Titterington, 1994) was used to calculate dates from these analyses. Tests on Mexican speleothem SSJ2 gave excellent results allowing a revised dating scheme to be adopted. Tests on some sub-samples from Chinese Speleothems were generally unsuccessful due to analytical errors.
The isotope 210Pb was used to date the top surface of one speleothem. A constant growth rate was inferred which was significantly less than that calculated from the 230Th - 234U dating method. This was thought to be due to the former techniques inability to resolve growth rates of periods of less than 200 years.
Despite the dating errors associated with each speleothem the records of PSV compare well with each other and with contemporaneous records from China, Japan and also the UK (for the Spanish record). In addition. agreement with PSV data modelled from observatory records suggested that westward drift of the non-dipole geomagnetic field was predominant during the past 10ka.

Genesis of the Sanbaqi deposit: a paleokarst-hosted uranium deposit in China, 1997,
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Min M. , Zheng D. , Shen B. , Wen G. , Wang X. , Gandhi S. S. ,

Uranium-series ages of speleothems from South Andros, Bahamas: Implications for Quaternary sea-level history and palaeoclimate, 1998,
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Smart P. L, Richards D. A. , Edwards R. L.

Late Pleistocene microtine rodents from Snake Creek Burial Cave, White Pine County, Nevada, 1998,
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Bell Cj, Mead Ji,
A total of 395 microtine rodent specimens recovered from Snake Creek Burial Cave (SCBC) are referred to Microtus SP. and Lemmiscus curtatus. Radiocarbon and Uranium series dates indicate an ae for these fossils of between 9460 160) yr. B.P. and 15,1000 700 yr, B.P. The sample of lower first molars of Lemmiscus includes 4-, 5-, and B-closed triangle morphotypes. Earlier reports of the 4-closed triangle morphotype are from Irvingtonian deposits in Colorado, Nevada, and New Mexico and from early Rancholabrean deposits in Washington. The morphotype is not known in living populations of Lemmiscus. SCBC specimens constitute the youngest record of the 4-closed triangle morphotype and are the only-specimens reported item the late Rancholabrean. Thc time of disappearance of Lemmiscus with this molar morphology is unknown, but populations with this morphotype possibly became extinct at or near the end of the Pleistocene

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