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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 kankar; kunkar is (australian.) see caliche.?

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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 luminescence (Keyword) returned 62 results for the whole karstbase:
Showing 16 to 30 of 62
High-resolution records of soil humification and paleoclimate change from variations in speleothem luminescence excitation and emission wavelengths, 1998, Baker A, Genty D, Smart Pl,
Recent advances in the precision and accuracy of the optical techniques required to measure luminescence permit the nondestructive analysis of solid geologic samples such as speleothems (secondary carbonate deposits in caves). In this paper we show that measurement of speleothem luminescence demonstrates a strong relationship between the excitation and emission wavelengths and both the extent of soil humification and mean annual rainfall. Raw peat with blanket bog vegetation has the highest humification and highest luminescence excitation and emission matrix wavelengths, because of the higher proportion of high-molecular-weight organic acids in these soils. Brown ranker and rendzina soils with dry grassland and woodland cover have the lowest wavelengths. Detailed analysis of one site where an annually laminated stalagmite has been deposited over the past 70 yr during a period with instrumental climate records and no vegetation change suggests that more subtle variations in luminescence emission wavelength correlate best with mean annual rainfall, although there is a lag of approximately 10 yr. These results are used to interpret soil humification and climate change from a 130 ka speleothem at an upland site in Yorkshire, England. These data provide a new continuous terrestrial record of climate and environmental change for northwestern Europe and suggest the presence of significant variations in wetness and vegetation within interglacial and interstadial periods

Fluorescence wavelength and intensity variations of cave waters, 1999, Baker A, Genty D,
The fluorescence properties of groundwaters percolating into four cave systems have been monitored over the period 1997-1998. Fluorescence was excited between 220 and 400 nm and the emission measured from 300 to 500 nm using a fluorescence spectrophotometer. Three fluorescence centres were observed; one at the excitation-emission pair of 290-340:395-430 nm, (humic-like, probably fulvic acid), one at 265-280:300-370 nm (protein like) and a less defined region of high fluorescence at 230-280:310-420 nm (humic and/or protein like). The most consistent fluorescence intensity was observed in the excitation-emission pair of 290-340:395-430 nm, attributed to a fulvic acid source. Subtle differences (5%) in the fluorescence excitation and emission wavelength of this fluorescence peak in the groundwater were observed between the four sites, and the fluorescence intensity varied considerably ( x 60) between the four sites. Both the wavelength and the intensity variations in fluorescence are caused by the differences in the vegetation cover, soil type and humification. Data from the most intensely monitored site (Brown’s Folly Mine, England; 9 sample stations, 10-20 days frequency sampling) revealed no spatial variability in the 290-340:395-430 nm (fulvic acid) fluorescence; in contrast time-series analysis suggests that the seasonal variations do occur, with a decrease in the emission wavelength correlating with the first (autumn) peak in fluorescence intensity, and a decrease in the excitation wavelength correlating with a second (winter) fluorescence intensity peak. Results demonstrate the potential of utilising fluorescence wavelength variations in sourcing karst groundwaters, and as a possible palaeoenvironmental proxy of the overlying soil conditions if trapped within the cave speleothems

Variations in stalagmite luminescence laminae structure at Poole's Cavern, England, AD 1910{}1996: calibration of a palaeoprecipitation proxy, 1999, Baker A, Proctor Cj, Barnes Wl,
Duplicate records of variations in the structure of stalagmite annual luminescence laminae are investi gated for the period ad 1910 to 1996 for Poole's Cavern, Buxton, central England. For the two stalagmites, 88% of the years have luminescence laminae that exhibit a near sinusoidal shape with no structural variations. However 10 laminae (12% of total) exhibit a double band structure; these are demonstrated to occur in years with high monthly or daily mean precipitation. It is suggested that high intensity (.60 mm d- 1) and high quantity (.250 mm per month) of precipitation may flush luminescent organic material onto the stalagmites from either the soil or groundwater zones and generate a double lamina. However, not all precipitation events generated double laminae. High-intensity events in summer were ineffective due to a soil moisture deficit and/or interception by the woodland canopy. High-rainfall months (.250 mm) failed to generate double laminae when preceded by two or more months of greater than 150 mm, suggesting exhaustion of the organic acid supply can occur. When compared to monthly precipitation data for Buxton, laminae shape and the percentage of double laminae of the Poole's Cavern stalagmites are best explained by a centre-weighted running mean of the preceding six to seven months' precipitation. The palaeoclimate potential of structural variations in stalagmite luminescence laminae is discussed

Comparison of the luminescence intensity of speleothem feed waters from six cave systems, 2000, Baker A.

Speleothem organic acid luminescence intensity ratios: A new palaeoenvironmental proxy, 2000, Baker A. , Bolton Lucy

Is it always dark in caves?, 2000, Badino Giovanni
Underground natural sources of visible light are considered. The main light producer is Cerenkov radiation emitted in air, water and rock by cosmic ray muons, that depends, in a complex way, on shape of mountain and of caves. In general the illumination increases linearly with the cavity dimensions. Other light sources are from secondary processes generated by radioactive decays in rock from minerals luminescence. The natural light fluxes in caves are in general easy to detect but are not used from underground life.

Verification of the causes of glaciations and sea level changes using the records of calcite speleothems, 2000, Forti Paolo, Georgiev Leonid, Georgieva Desislava, Lundberg Joyce, Sanabria Michael, Shopov Yavor, Stoykova Diana, Tsankov Ludmil
The luminescence of calcite speleothems displays an exponential dependence on soil temperature unless there is a dense cover of forest over the cave to dampen it. This relationship is determined primarily by the strength of solar visible and infrared radiation. It is suggested that, as a consequence, the microzonal variations of luminescence often found in speleothems can be used as a proxy index of Solar Insolation. The luminescence solar insolation proxy record of a speleothem from Jewel Cave, South Dakota, USA, was found to display millenial and centennial cycles in the record. It exhibits a rapid increase in solar insolation at 139 5.5 kyrs. This increase precedes that suggested by the Orbital theory by about 10,000 years and is due to superimposition of the most powerful cycle in solar luminosity of 11.5 kyrs, upon the curve of orbital variations. The record from a speleothem in Duhlata Cave, Bulgaria matches that of South Dakota within the limits of dating error, indicating that both of these records (which are 10,000 km apart) measure global solar insolation controls rather than local paleotemperature variations.

Karstification and tectonic evolution of the Jabal Madar (Adam Foothills, Arabian platform) during the Upper Cretaceous, 2000, Montenat C. , Soudet H. J. , Barrier P. , Chereau A. ,
A palaeokarst system of Turonian age, located on the Arabian platform, at the front of the ophiolitic nappes of Oman (Jabal Madar, Adam foothills), is described and placed in its geodynamic context. The development of the karst network in a vadose context was favoured by an episode of fracturing (N-S to NW-SE fractures) that affected the Cenomanian platform carbonates of the Natih Formation. The karstic filling comprises two main types of speleothems: - laminated bioclastic calcarenites with graded bedding essentially deposited by gravity currents in a vadose regime; - crystallisation of large masses of white calcite in a saturated regime. The calcite was deposited during several episodes, and often constitutes most of the filling. The episode of uplift and emergence, accompanied by fracturing which favoured the development of the Madar karstic system, was probably induced by the swelling of the Arabian platform, in response to the initiation of the ophiolitic nappe obduction. Karstic filling probably occurred during the rise of marine level, what is suggested by mixing of vadose and marine influences (production of bioclastic calcarenites and later dolomitisation of these ones; crystallisation of white calcite of various origins as evidenced by cathodoluminescence data and carbonate isotopes). At the beginning of the Senonian, the Jabal Madar area was again submerged and incorporated in a relatively deep foreland basin where pelagic marls and turbidites were deposited (Muti Formation). The Jabal Madar (and its karstic system) and the whole of the Adam foothills were affected by folding towards the end of the Cretaceous, during the final phase of thrusting of the Omani nappes. The folding was strongly reactivated by post-obduction compressional movement which occurred during Miocene times

Dolomitization and Dolomite Neomorphism: Trenton and Black River Limestones (Middle Ordovician) Northern Indiana, U.S.A, 2000, Yoo Chan Min, Gregg Jay M. , Shelton Kevin L. ,
The Trenton and Black River Limestones are dolomitized extensively along the axis of the Kankakee Arch in Indiana, with the proportion of dolomite decreasing to the south and southeast of the arch. Planar and nonplanar dolomite replacement textures and rhombic (type 1) and saddle (type 2) void-filling dolomite cements are present. Three stages of dolomitization, involving different fluids, are inferred on the basis of petrographic and geochemical characteristics of the dolomites. Nonferroan planar dolomite has relatively high {delta}18O values (-1.8 to -6.1{per thousand} PDB) and has 87Sr/86Sr ratios (0.70833 to 0.70856) that overlap those of Middle Ordovician seawater. Petrography, geochemistry, and the geometry of the dolomitized body suggest that the planar dolomite was formed in Middle and Late Ordovician seawater during the deposition of the overlying Maquoketa Shale. Ferroan planar and nonplanar dolomite occurs in the upper few meters of the Trenton Limestone, confined to areas underlain by planar dolomite. This dolomite contains patches of nonferroan dolomite with cathodoluminescence (CL) characteristics similar to underlying planar dolomite. Ferroan dolomite has relatively low {delta}18O values (-5.1 to -7.3{per thousand} PDB) and has slightly radiogenic 87Sr/86Sr ratios (0.70915 to 0.70969) similar to those obtained for the overlying Maquoketa Shale. These data indicate that ferroan dolomite formed by neomorphism of nonferroan planar dolomite as fluids were expelled from the overlying Maquoketa Shale during burial. The absence of ferroan dolomite at the Trenton-Maquoketa contact, in areas where the earlier-formed nonferroan planar dolomite also is absent, indicates that the fluid expelled from the overlying shale did not contain enough Mg2 to dolomitize limestone. Type 1 dolomite cement has isotopic compositions similar to those of the ferroan dolomite, suggesting that it also formed from shale-derived burial fluids. CL growth zoning patterns in these cements suggest that diagenetic fluids moved stratigraphically downward and toward the southeast along the axis of the Kankakee Arch. Type 2 saddle dolomite cements precipitated late; their low {delta}18O values (-6.0 to -7.0{per thousand} PDB) are similar to those of the type 1 dolomite cement. However, fluid-inclusion data indicate that the saddle dolomite was precipitated from more saline, basinal fluids and at higher temperatures (94{degrees} to 143{degrees}C) than the type 1 cements (80{degrees} to 104{degrees}C). A trend of decreasing fluid-inclusion homogenization temperatures and salinities from the Michigan Basin to the axis of Kankakee Arch suggests that these fluids emerged from the Michigan Basin after precipitation of type 1 cement

The role of evaporites in the genesis of base metal sulphide mineralisation in the Northern Platform of the Pan-African Damara Belt, Namibia: geochemical and fluid inclusion evidence from carbonate wa, 2000, Chetty D, Frimmel He,
The Otavi Mountain Land is a base metal sulphide ore province in northern Namibia where deposits are hosted by platform carbonates of the Otavi Group in a foreland fold-and-thrust belt on the northern edge of the Pan-African Damara Belt. Deposits have been classified as the Berg Aukas- or Tsumeb-types, based on differences in ore association? stratigraphic position and geochemistry of ores and gangue carbonates. Mineralisation at these deposits is accompanied by carbonate alteration in the form of dolomite and calcite veins, carbonate recrystallisation, calcitisation and carbonate silicification. Based on cathodoluminescence imaging, trace and rare earth element (REE), O and C isotope, and fluid inclusion data, a series of carbonate generations, constituting wall rock alteration around the Tsumeb and Kombat (Tsumeb-type) and Berg Aukas (Berg Aukas-type) deposits, was established. Similar data obtained on the recently discovered Khusib Springs deposit indicate a strong affinity to Tsumeb-type deposits. Tsumeb-type deposits are distinguished from Berg Aukas-type deposits by having trace element and REE concentrations that are significantly higher in the alteration products compared to the carbonate host rocks. Only around Tsumeb-type deposits a relative enrichment in light REE is noted for the hydrothermal carbonate generations that are cogenetic with the main stage of mineralisation. Microthermometric results from fluid inclusions in carbonate alteration phases and associated quartz indicate relatively high salinity (17-33 wt% NaCl equivalent) for the main mineralising and subsequent sulphide remobilisation stages at the deposits investigated. Estimated mineralisation temperatures are significantly higher for Tsumeb-type deposits (370-405 degrees C) with early sulphide remobilisation in Tsumeb at 275 degrees C, whereas they are lower at Berg Aukas (up to 255 degrees C). Fluid inclusion leachate analysis suggests that most of the observed salinity can be ascribed to dissolved, predominantly Ca- and Mg-carbonates and chlorides with subordinate NaCl. Na-Cl-Br leachate systematics indicate a derivation of the fluid salinity from the interaction with evaporitic rocks en route. Tsumeb-type mineralisation is interpreted to be derived from fluids expelled during Pan-African orogeny in the more intensely deformed internal zones of the Damara Belt further south. When the high salinity fluids reached the carbonate platform after having scavenged high concentrations of base metals, base metal sulphide precipitation occurred in zones of high porosity, provided by karst features in the carbonate sequence. Results obtained for the Berg Aukas-type deposits emphasise their derivation from basinal brines, similar to Mississippi Valley-type deposits, and confirm that mineralisation of the Berg Aukas- and Tsumeb-types are both spatially and temporally distinct

Photoluminescence Imaging of Speleothem Microbanding with a High-Resolution Confocal Scanning Laser Macroscope, 2000, Ribes, A. C. , Lundberg, J. , Waldron, D. J. , Vesely, M. , Damaskinos, S. , Guthrie, S. And Dixon, T.

Formation of dolomite mottling in Middle Triassic ramp carbonates (Southern Hungary), 2000, Torok A. ,
The Middle Triassic carbonates of the Villany Mountains were deposited on a homoclinal carbonate ramp. Many of the carbonates from the 700 m-thick sequence show partial or complete dolomitization. The present paper describes dolomites that occur in a limestone unit as irregular mottles and as pore- and fracture-filling cements. Replacement-type scattered dolomite rhombs in the mottles having inclusion-rich, very dull luminescent cores and limpid non-luminescent outer zones represent the initial phase of dolomitization. The isotopic composition of these dolomites (delta(13)C = .30 parts per thousand VPDB, delta(18)O = -3.60 parts per thousand VPDB) is similar to that of the calcitic micrite (delta(13)C = .6 parts per thousand VPDB, delta(18)O = -4.00 parts per thousand VPDB) indicating that no external fluids were introduced during dolomite formation. The elevated Sr content of the micrites implies that sediment was originally aragonite or high-Mg calcite. Dolomitization took place in the burial realm from a 'marine' pore-fluid in a partly closed system. Later fracture-related saddle dolomite reflects elevated formation temperatures and increasing burial. Five calcites were identified. Multiple generations of calcite-filled fractures were formed during burial diagenesis generally having dull or no luminescence (delta(13)C = .80 parts per thousand VPDB, delta(18)O = -6.40 parts per thousand VPDB). The latest phase calcites are related to karst formation, having a very negative isotopic composition (delta(13)C = -5.0 to -7.2 parts per thousand VPDB and delta(18)O approximate to -7.44 parts per thousand VPDB). The karst-related processes include dissolution, calcite precipitation and partial replacement of dolomites by complex zoned bright yellow calcite. The timing of dolomitization is uncertain, but the first phase took place in a partly closed system prior to stylolite formation. Late-stage saddle dolomites were precipitated during maximum burial in the Cretaceous. The dissolution of dolomites and karst-related calcite replacement was not earlier than Late Cretaceous. (C) 2000 Elsevier Science B.V. All rights reserved

Thermoluminescence dating of dune ridges in western Victoria, 2000, White, Susan

Absolute dating of the Pleistocene dune ridges of southwestern Victoria establishes a time frame for speleogenesis of syngenetic karst in such dune calcarenites. The dunes were deposited during the late mid-Pleistocene.

Geochemical study of calcite veins in the Silurian and Devonian of the Barrandian Basin (Czech Republic): evidence for widespread post-Variscan fluid flow in the central part of the Bohemian Massif, 2000, Suchy V. , Heijlen W. , Sykorova I. , Muchez Ph. , Dobes P. , Hladikova J. , Jackova I. , Safanda J. , Zeman A.

Carbonate fracture cements in limestones have been investigated by fluid inclusion and stable isotope analysis to provide insight into fluid evolution and deformation conditions of the Barrandian Basin (Silurian–Devonian) of the Czech Republic. The fractures strike generally north–south and appear to postdate major Variscan deformation. The most common fracture cement is calcite that is locally accompanied by quartz, natural bitumen, dolomite, Mn-oxides and fluorite. Three successive generations of fracture-filling calcite cements are distinguished based on their petrographical and geochemical characteristics. The oldest calcite cements (Stage 1) are moderate to dull brown cathodoluminescent, Fe-rich and exhibit intense cleavage, subgrain development and other features characteristic of tectonic deformation. Less tectonically deformed, variable luminescent Fe-poor calcite corresponds to a paragenetically younger Stage 2 cement. First melting temperatures, Te, of two-phase aqueous inclusions in Stages 1 and 2 calcites are often around 2208C, suggesting that precipitation of the cements occurred from H2O–NaCl fluids. The melting temperature, Tm, has values between 0 and 25.88C, corresponding to a low salinity between 0 and 8.9 eq. wt% NaCl. Homogenization temperatures, Th, from calcite cements are interpreted to indicate precipitation at about 708C or less. No distinction could be made between the calcite of Stages 1 and 2 based on their fluid inclusion characteristics. In some Stage 2 cements, inclusions of highly saline (up to 23 eq. wt% NaCl) brines appear to coexist with low-salinity inclusions. The low salinity fluid possibly contains Na-, K-, Mg- and Ca-chlorides. The high salinity fluid has a H2O–NaCl–CaCl2 composition. Blue-to-yellow-green fluorescing hydrocarbon inclusions composed of medium to higher API gravity oils are also identified in some Stages 1 and 2 calcite cements. Stage 1 and 2 calcites have d 18O values between 213.2‰ and 27.2‰ PDB. The lower range of the calculated d 18O values of the ambient fluids (23.5‰ to 1 2.7‰ SMOW) indicate precipitation of these cements from deeply circulating meteoric waters. The presence of petroleum hydrocarbon inclusions in some samples is interpreted to reflect partial mixing with deeper basinal fluids. The paragenetically youngest Stage 3 calcite cement has only been encountered in a fewveins.These calcites are characterised by an intensely zoned luminescence pattern, with bright yellow and non-luminescent zones. Inclusions of Mn-oxides and siliceous sinters are commonly associated with Stage 3 calcite, which is interpreted to have precipitated from shallower meteoric waters. Regional structural analysis revealed that the calcite veins of the Barrandian basin belong to a large-scale system of north–south-trending lineaments that run through the territory of the Czech Republic. The veins probably reflect episodes of fluid migration that occurred along these lineaments during late stages of the Variscan orogeny

La capture de la Moselle : nouvelles donnes chronologiques par datations U/Th sur splothmes, 2001, Losson Benot, Quinif Yves
The Moselle piracy is one of the most important changes of the hydrographic network in Lorraine (France). For a long time, this phenomenon has been presumed to be relatively recent (at the end of the Middle Pleistocene) because of the well preserved fluvial morphologies and deposits. With new relations between the above ground and subterranean parameters in the piracy area, the capture has been dated from 300 ka by the U/Th method on speleothem. This evaluation reveals an earlier time for the phenomenon, and is more precise than those proposed up to now. The latter were derived from the North-european glacial chronology and one thermoluminescence date obtained in the downstream valley of Meuse. In fact, the improvements in absolute datings, through different methods and U/Th in particular, lead geomorphologists to abandon the simple relation between the glacial-interglacial periods and the accumulation-erosion processes in rivers.

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