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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. ...

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Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
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Featured articles from other Geoscience Journals
Karst environment, Culver D.C.
Mushroom Speleothems: Stromatolites That Formed in the Absence of Phototrophs, Bontognali, Tomaso R.R.; D’Angeli Ilenia M.; Tisato, Nicola; Vasconcelos, Crisogono; Bernasconi, Stefano M.; Gonzales, Esteban R. G.; De Waele, Jo
Calculating flux to predict future cave radon concentrations, Rowberry, Matt; Marti, Xavi; Frontera, Carlos; Van De Wiel, Marco; Briestensky, Milos
Microbial mediation of complex subterranean mineral structures, Tirato, Nicola; Torriano, Stefano F.F;, Monteux, Sylvain; Sauro, Francesco; De Waele, Jo; Lavagna, Maria Luisa; D’Angeli, Ilenia Maria; Chailloux, Daniel; Renda, Michel; Eglinton, Timothy I.; Bontognali, Tomaso Renzo Rezio
Evidence of a plate-wide tectonic pressure pulse provided by extensometric monitoring in the Balkan Mountains (Bulgaria), Briestensky, Milos; Rowberry, Matt; Stemberk, Josef; Stefanov, Petar; Vozar, Jozef; Sebela, Stanka; Petro, Lubomir; Bella, Pavel; Gaal, Ludovit; Ormukov, Cholponbek;
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Your search for electron microscopy (Keyword) returned 29 results for the whole karstbase:
Showing 1 to 15 of 29
Black Phytokarst from Hell, Cayman Islands, British West Indies, 1973, Folk Rl, Roberts Hh, Moore Ch,
Erosion by filamentous algae, comparison with ordinary karst, scanning electron microscopy, Bluff Limestone

Scanning Electron Microscopy and Energy Dispersive X-Ray Analysis of Artificial and Natural Substrates from the Phantom Flowstone of Sulphur River in Parker Cave, Kentucky, 1988, Olson Rick A. , Thompson D. Bruce

On some cave minerals from Northern Norway., 1995, Lauritzen Steinerik, Onac Bogdan Petroniu
The present paper aims to point out the results of 31 samples from some Norwegian caves that have been analysed with respect to their mineralogical composition. Identification of the minerals was done by X-ray diffraction, thermal, infrared spectroscopy and scanning electron microscopy. Seventeen minerals were identified belonging to 4 groups: carbonates, sulphates, oxides-hydroxides and silicates.

Evidence for Geomicrobiological Interactions in Guadalupe Caves, 2000, Northup, D. E. , Dahm, C. N. , Melim, L. A. , Spilde, M. N. , Crossey, L. J. , Lavoie, K. H. , Mallory, L. M. , Boston, P. J. , Cummingham, K. I. , Barns, S. M.
Caves in the Guadalupe Mountains offer intriguing examples of possible past or present geomicrobiological interactions within features such as corrosion residues, pool fingers, webulites, u-loops, and moonmilk. Scanning electron microscopy, transmission electron microscopy, molecular biology techniques, enrichment cultures, bulk chemistry, and X-ray diffraction techniques have revealed the presence of iron- and manganese-oxidizing bacteria in corrosion residues, which supports the hypothesis that these organisms utilize reduced iron and manganese from the limestone, leaving behind oxidized iron and manganese. Metabolically active populations of bacteria are also found in punk rock beneath the corrosion residues. Microscopic examination of pool fingers demonstrates that microorganisms can be inadvertently caught and buried in pool fingers, or can be more active participants in their formation. Enrichment cultures of moonmilk demonstrate the presence of a variety of microorganisms. Humans can have a deleterious impact on microbial communities in Guadalupe caves

DETRITAL ORIGIN OF A SEDIMENTARY FILL, LECHUGUILLA CAVE, GUADALUPE MOUNTAINS, NEW MEXICO, 2000, Foos Am, Sasowsky Id, Larock Ej, Kambesis Pn,
Lechuguilla Cave is a hypogene cave formed by oxidation of ascending hydrogen sulfide from the Delaware Basin. A unique sediment deposit with characteristics suggesting derivation from the land surface, some 285 m above, was investigated. At this location, the observed stratigraphy (oldest to youngest) was: bedrock floor (limestone), cave clouds (secondary calcite), calcite-cemented silstone, finely laminated clay, and calcite rafts. Grain-size analysis indicates that the laminated clay deposits are composed of 59-82% clay-size minerals. The major minerals of the clay were determined by X-ray diffraction analysis and consist of interstratified illite-smectite, kaolinite, illite, goethite, and quartz. Scanning electron microscopy observations show that most of the clay deposit is composed of densely packed irregular-shaped clay-size flakes. One sample from the top of the deposit was detrital, containing well-rounded, silt-size particles. Surface soils are probably the source of the clay minerals. The small amount of sand- and silt-size particles suggests that detrital particles were transported in suspension. The lack of endellite and alunite is evidence that the clays were emplaced after the sulfuric-acid dissolution stage of cave formation. Fossil evidence also suggests a previously existing link to the surface

Acidic cave-wall biofilms located in the Frasassi Gorge, Italy, 2000, Vlasceanu L. , Sarbu S. M. , Engel A. S. , Kinkle B. K. ,
Acidic bioflms present on cave walls in the sulfidic region of the Frasassi Gorge, Italy, were investigated to determine their microbial composition and their potential role in cave formation and ecosystem functioning. All biofilm samples examined had pH values <1.0. Scanning electron microscopy of the biofilms revealed the presence of various filaments and rods associated in large clusters with mineral crystals. Qualitative energy-dispersive x-ray analysis was used to determine that the crystals present on the cave walls, associated with the microbial biofilm, were composed of calcium and barium sulfate. Ribosomal RNA-based methods to determine the microbial composition of these biofilms revealed the presence of at least two strains of potential acidophilic, sulfur-oxidizing bacteria, belonging to the genera Thiobacillus and Sulfobacillus. An acid producing strain of Thiobacillus sp. also was obtained in pure culture. Stable isotope ratio analysis of carbon and nitrogen showed that the wall biofilms are isotopically light, suggesting that in situ chemoautotrophic activity plays an important role in this subsurface ecosystem

Depositional environment for metatyuyamunite and related minerals from Caverns of Sonora, TX (USA), 2001, Onac Bogdan P. , Veni George, White William B. ,
A new mineral association composed of metatyuyamunite, celestite, opal and several minor crystalline phases has been identified in the Caverns of Sonora (Texas). The minerals were identified by means of X-ray diffractometry and optical and scanning electron microscopy. The main component of this association is metatyuyamunite, a uranyl vanadate mineral that appears as aggregates of sub-millimeter platy-like crystals that are often covered by botryoidal opal coatings. The orthorhombic unit cell of the Sonora metatyuyamunite had parameters a = 10.418, b = 8.508, and c = 17.173 A. Opal and celestite formed either directly over the yellow crust or along the cracks that traverse the limy mud on which metatyuyamunite was precipitated. The secondary uranium-vanadium minerals described herein were precipitated in the final stages of cave development

Leonite [K2Mg(SO4)2{middle dot}4H2O], konyaite [Na2Mg(SO4)2{middle dot}5H2O] and syngenite [K2Ca(SO4)2{middle dot}H2O] from Tausoare Cave, Rodnei Mts, Romania, 2001, Onac B. P. , White W. B. , Viehmann I. ,
Tausoare Cave is renowned in Romania for its gypsum and mirabilite speleothems. Of interest are the white crystalline speleothems formed on the floor of the Sala de Mese' (Dining Room) that were previously described as consisting of mirabilite. The samples we collected reveal crystals of two different habits. One shows the characteristic mirabilite fibrous crystals (cotton-like speleothem) while the other formed bladed and short prismatic crystals which comprise the delicate cave flowers'. The mineral association was characterized by means of X-ray analysis, scanning electron microscopy and electron microprobe. Beside thenardite (dehydration product of mirabilite) we also identified three sulphate minerals: leonite [K2Mg(SO4)2{middle dot}4H2O], syngenite [K2Ca(SO4)2{middle dot}H2O] and konyaite [Na2Mg(SO4)2{middle dot}5H2O]. Of these, leonite and konyaite have never been reported in a cave environment. This paper describes the mineralogy of this particular sulphate deposit and offers some viewpoints on the crystallogenesis

Black carbon pollution of speleothems by fine urban aerosols in tourist caves, 2003, Jeong Gi Young, Kim Soo Jin, Chang Sae Jung,
Speleothems in the karst caves of South Korea, which receive many visitors, are losing their aesthetic appeal due to black coloring. Mineralogical, textural, and chemical analyses were conducted on the speleothems to discover the cause of the discoloration. An abrupt color change from the natural color seen in the inner zones to the black color of the outer zones suggests that pollution commenced just after the opening of caves to visitors, and has continued since then. The main mineral compositions of both the outer black and the inner layers are the same, but the concentration of non-carbonate carbon is much higher in the black layers than in the inner layers. Electron microscopy showed that chain-like agglomerates (ca. 0.2-1.1 {micro}m diameter) of sub-micrometer carbon spheres (ca. 0.02-0.05 {micro}m diameter) are absent from the inner layer but present in the black layer, as well as in the cave aerosol. On the basis of their sub-micrometer size, agglomeration pattern, and composition, the carbon spheres and their agglomerates are considered to originate mostly from automobile exhaust. They are presumed to have been carried into the caves by visitors from urban environments and then deposited on the surface of growing speleothems. Protection of speleothems from discoloration requires control of these fine anthropogenic aerosols

Palaeolithic painting matter: natural or heat-treated pigment?, 2004, Chalmin E, Vignaud C, Menu M,
Analyses of archaeological materials attempt to rediscover the know-how of Prehistoric men by determining the nature of the matter, its preparation mode, and its geographic origin. The preparation mode of painting matter of Palaeolithic rock art consisted not only in mixing and grinding but also in heat-treatment. Palaeolithic painters used two main colors: red (iron oxide, hematite) and black (charcoal or manganese oxide). The different phases of manganese oxides can be distinguished using their elemental composition, their structure and the oxidation state of the Mn ion (II, III, IV). Their transformation during heat-treatment has been studied on mineralogical reference samples by means of transmission electron microscopy (TEM) either coupled or not with a heating stage (in situ). These studies have enabled us to understand the transformation mechanisms of manganese oxides and also to gain insights into the preparation procedures of painting materials during the Palaeolithic period. The painting samples studied in this paper come from the cave of Lascaux (Dordogne, France). These studies allow us to distinguish between natural or heat-treated manganese oxides

Involvement of microorganisms in the formation of carbonate speleothems in the Cervo Cave (L'Aquila-Italy), 2004, Cacchio P, Contento R, Ercole C, Cappuccio G, Martinez Mp, Lepidi A,
Much is known about the bacterial precipitation of carbonate rocks, but comparatively little is known about the involvement of microbes in the formation of secondary mineral structures in caves. We hypothesized that bacteria isolated from calcareous stalactites, which are able to mediate CaCO3 precipitation in vitro, play a role in the formation of carbonate speleothems. We collected numerous cultivable calcifying bacteria from calcareous speleothems from Cervo cave, implying that their presence was not occasional. The relative abundance of calcifying bacteria among total cultivable microflora was found to be related to the calcifying activity in the stalactites. We also determined the delta(13)C and delta(18)O values of the Cervo cave speleothems from which bacteria were isolated and of the carbonates obtained in vitro to determine whether bacteria were indeed involved in the formation of secondary mineral structures. We identified three groups of biological carbonates produced in vitro at 11degreesC on the basis of their carbon isotopic composition: carbonates with delta(13)C values ( a) slightly more positive, (b) more negative, and (c) much more negative than those of the stalactite carbonates. The carbonates belonging to the first group, characterized by the most similar delta(13)C values to stalactites, were produced by the most abundant strains. Most of calcifying isolates belonged to the genus Kocuria. Scanning electron microscopy showed that dominant morphologies of the bioliths were sherulithic with fibrous radiated interiors. We suggest a mechanism of carbonate crystal formation by bacteria

The distribution and life history of Arrhopalites caecus (Tullberg): Order: Collembola, in Wind Cave, South Dakota, USA., 2005, Moore J. C. , Saunders P. , Selby G. , Horton H. , Chelius M. K. , Chapman A. , Horrocks R. D.
Individuals of the collembolan species Arrhopalites caecus (Tullberg) were collected from drip pools within Wind Cave, South Dakota, at Methodist Church adjacent to the Natural Entrance Tour Route and Room Draculum near survey marker NP-39. Specimens were identified as A. caecus using direct interference and scanning electron microscopy. Molecular analysis of the D2 region of 28S rDNA was performed and the sequences were deposited in Genbank (accession number AY239037). We determined that our population of A. caecus reproduced parthenogenetically by successively isolating and rearing eggs through the F4 generation on 9:5 plaster:charcoal media maintained at 21C, and by the absence of males. Molecular analysis of 16S rDNA for bacterium within our specimens failed to detect the ?-pro-teobacterium (Rickettseales) Wolbachia. Generation times, fecundity, and molt frequency were consistent with other reports for Collembola.

Petrographic and geochemical study on cave pearls from Kanaan Cave (Lebanon), 2007, Nader Fadi. H.
The Kanaan cave is situated at the coastal zone, north of Beirut City (capital of Lebanon). The cave is located within the upper part of the Jurassic Kesrouane Formation (Liassic to Oxfordian) which consists mainly of micritic limestone. Twenty seven cave pearls were subjected to petrographic (conventional and scanning electron microscopy) and geochemical analyses (major/trace elements and stable isotopes). The cave pearls were found in an agitated splash-pool with low mud content. They are believed to have formed through chemical precipitation of calcite in water over-saturated with calcium. The nucleus and micritic laminae show ? 18OV-PDB values of about -5.0 and ? 13C V-PDB values of -11.8, while the surrounding calcite spar laminae resulted in ?18OV-PDB ranging between -5.3 and -5.2, and ? 13C V-PDB between -12.3 and -12.1. A genesis/diagenesis model for these speleothems is proposed involving recrystallization which has selectively affected the inner layers of the cave pearls. This is chiefly invoked by sparry calcite crystals invading the inner micrite cortical laminae and the nuclei (cross-cutting the pre-existing mud-envelopes), and the slight depletion in ? 18O values from inner to outer cortical layers. The calculated ? 18OV-SMOW of the water (-4.2) matches with data on meteoric water signature for the central eastern Mediterranean region.

Biotic versus abiotic calcite formation on prehistoric cave paintings: the Arcy-sur-Cure 'Grande Grotte' (Yonne, France) case, 2007, Chalmin E, D'orlye F, Zinger L, Charlet L, Geremia Ra, Orial G, Menu M, Baffier D, Reiche I,
The Grande Grotte' cave at Arcy-sur-Cure (Yonne, France) with its prehistoric paintings shows important calcite concretions. Two types of calcite have been observed on the wall: translucent yellowish layers and opaque white or grey layers that completely obstruct the paintings. Other calcite types are present in the lakes of the cave (floating calcite rafts at the surface of the lake and soft calcite at the bottom of the lake). The morphology of the different calcites was observed at different scales by optical microscopy with normal and polarized light, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The elemental composition was measured by using particle-induced X-ray emission (micro-PIXE) and the structure by X-ray diffraction (XRD), infrared (FT-IR) and Raman spectroscopy. The bacterial diversity and its role in calcite formation were assessed by culture and 16S-SSCP in order to distinguish and to assess various abiotic and biotic formation mechanisms. The investigation of calcite characteristics enables conclusions on the formation mechanism and on a biotic or abiotic origin of the calcites. The change of calcite types on the walls reveals changes of the environmental cave parameters. In addition, interactions of calcites with the prehistoric paint layer could be evaluated

Petrographic and geochemical study on cave pearls from Kanaan Cave (Lebanon), 2007, Nader Fadi H.
The Kanaan cave is situated at the coastal zone, north of Beirut City (capital of Lebanon). The cave is located within the upper part of the Jurassic Kesrouane Formation (Liassic to Oxfordian) which consists mainly of micritic limestone. Twenty seven cave pearls were subjected to petrographic (conventional and scanning electron microscopy) and geochemical analyses (major/trace elements and stable isotopes). The cave pearls were found in an agitated splash-pool with low mud content. They are believed to have formed through chemical precipitation of calcite in water over-saturated with calcium. The nucleus and micritic laminae show ? 18OV-PDB values of about -5.0 and ? 13C V-PDB values of -11.8, while the surrounding calcite spar laminae resulted in ?18OV-PDB ranging between -5.3 and -5.2, and ? 13C V-PDB between -12.3 and -12.1. A genesis/diagenesis model for these speleothems is proposed involving recrystallization which has selectively affected the inner layers of the cave pearls. This is chiefly invoked by sparry calcite crystals invading the inner micrite cortical laminae and the nuclei (cross-cutting the pre-existing mud-envelopes), and the slight depletion in ? 18O values from inner to outer cortical layers. The calculated ? 18OV-SMOW of the water (-4.2) matches with data on meteoric water signature for the central eastern Mediterranean region.

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