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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 gully is a deep erosional channel [16].?

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Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
See all featured articles
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 microscopy (Keyword) returned 40 results for the whole karstbase:
Showing 1 to 15 of 40
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

Unusual speleothems resembling giant mushrooms occur in Cueva Grande de Santa
Catalina, Cuba. Although these mineral buildups are considered a natural heritage, their
composition and formation mechanism remain poorly understood. Here we characterize
their morphology and mineralogy and present a model for their genesis. We propose that
the mushrooms, which are mainly comprised of calcite and aragonite, formed during four
different phases within an evolving cave environment. The stipe of the mushroom is an
assemblage of three well-known speleothems: a stalagmite surrounded by calcite rafts
that were subsequently encrusted by cave clouds (mammillaries). More peculiar is the
cap of the mushroom, which is morphologically similar to cerebroid stromatolites and
thrombolites of microbial origin occurring in marine environments. Scanning electron
microscopy (SEM) investigations of this last unit revealed the presence of fossilized
extracellular polymeric substances (EPS)—the constituents of biofilms and microbial
mats. These organic microstructures are mineralized with Ca-carbonate, suggesting that
the mushroom cap formed through a microbially-influenced mineralization process. The
existence of cerebroid Ca-carbonate buildups forming in dark caves (i.e., in the absence
of phototrophs) has interesting implications for the study of fossil microbialites preserved
in ancient rocks, which are today considered as one of the earliest evidence for life on
Earth.


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

Fluoreszenzmikroskopische Untersuchung der Bakterienflora und Bestimmung ihrer heterotrophen Aktivitt in organisch belastetem und unbelastetem Grundwasser sandig-kiesiger Ablagerungen., 1981, Marxsen Jurgen
Bacteriological investigations were carried out in the groundwater of sandy and gravelly deposits of the river Fulda valley in an area named Johannesaue near the town Fulda (Hesse, Fed. Rep. of Germany). In January 1979 water samples were collected from 16 pumping tubes distributed in organically polluted and unpolluted areas. For characterizing the bacterial populations, methods used for surface waters were modified and, as far as the author is aware, these methods were used for the first time for investigations pertaining subterranean waters. The bacteria were counted by means of epifluorescence microscopy after staining the bacteria with the fluorochrome acridine orange. This technique renders possible the simultaneous registration of shape and size of bacteria. Parameters characterizing the heterotrophic bacterial activity were measured with 14C-labelled glucose. The number of bacteria in the groundwater collected through pumping tubes, varied from 1.4 to 11.3 million bacteria per ml. The relative glucose uptake potential vr, which was measured at one substrate concentration (600 microg glucose .1-1) where the maximum uptake velocity is almost reached, was 0.12; 0.74 microg glucose 1-1 .h-1. The corresponding specific potential was 0.02-0.18 microg glucose h-1 cell-1. The results agreed with the values of maximum uptake velocity Vmax which was measured at the same time in some of the groundwater samples. The data give first information about distribution of the number of bacteria and of heterotrophic bacterial activity in the groundwater of the investigation area. Relationships could be shown between the bacteriological parameters on the one hand and the concentration of oxygen and the values of COD measured with KMnO4 on the other hand.

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

Some remarks on the genus Microcharon Karaman in Greece, and description of M. agripensis n. sp. (Crustacea, Isopoda, Microparasellidae), 1994, De Laurentiis Paola, Galassi Diana M. P. , Pesce Giuseppe L.
Several samples of microparasellid isopods of the genus Microcharon Karaman were obtained in groundwater habitats of Greece. Four species are identified, and taxonomical and zoogeographical remarks on some rare or poorly known taxa are made. One species, herein described as Microcharon agripensis n. sp., is new to Science. M. latus prespensis Karaman, 1954, on account of the different morphology of the first and second male pleopods, and its partially overlapping distribution, in respect to M. latus Karaman, 1934, is definitively raised at specific rank. Supplementary descriptions and illustrations are reported for incompletely described species such as M. latus, M. prespensis stat. nov., M. major Karaman, 1954 and M. othrys Argano & Pesce, 1979. For some species, such as M. latus, M. othrys and M. antonellae Galassi, 1991, SEM preparations of the mouthparts, not well detailed with the optical microscopy, were carried out. According to data from the present study, a paleogeographical scenario of the Balkan Peninsula is briefly depicted in order to sketch the most significative events which led to the colonization and speciation of the Microcharon species in this area.

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

X-ray standing wave study of the Sr/Si(001)-(2 x 3) surface, 2003, Goodner D. M. , Marasco D. L. , Escuadro A. A. , Cao L. , Tinkham B. P. , Bedzyk M. J. ,
Sub-monolayer surface phases of Sr on Si(0 0 1) have been studied with low-energy electron diffraction (LEED) and X-ray standing waves (XSW). A (3 x 1) phase was observed after depositing 0.6-0.8 ML Sr on room-temperature Si(0 0 1). Annealing at 750-800degreesC caused a portion of the Sr to desorb and resulted in a sharp (2 x 3) LEED pattern. Normal Si(0 0 4) and off-normal Si(0 2 2) and Si(1 11) XSW measurements made on the (2 x 3) phase indicate that Sr atoms must sit at either cave or bridge sites. The XSW results also suggest that if a sufficiently low anneal temperature is used. the (2 x 3) phase co-exists with short-range ordered regions of Sr atoms located at valley-bridge sites. (C) 2003 Elsevier B.V. All rights reserved

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

Current issues and uncertainties in the measurement and modelling of air-vegetation exchange and within-plant processing of POPs, 2004, Barber Jl, Thomas Go, Kerstiens G, Jones Kc,
Air-vegetation exchange of POPs is an important process controlling the entry of POPs into terrestrial food chains, and may also have a significant effect on the global movement of these compounds. Many factors affect the air-vegetation transfer including: the physicochemical properties of the compounds of interest; environmental factors such as temperature, wind speed, humidity and light conditions; and plant characteristics such as functional type, leaf surface area, cuticular structure, and leaf longevity. The purpose of this review is to quantify the effects these differences might have on air/plant exchange of POPs, and to point out the major gaps in the knowledge of this subject that require further research. Uptake mechanisms are complicated, with the role of each factor in controlling partitioning, fate and behaviour process still not fully understood. Consequently, current models of air-vegetation exchange do not incorporate variability in these factors, with the exception of temperature. These models instead rely on using average values for a number of environmental factors (e.g. plant lipid content, surface area), ignoring the large variations in these values. The available models suggest that boundary layer conductance is of key importance in the uptake of POPs, although large uncertainties in the cuticular pathway prevents confirmation of this with any degree of certainty, and experimental data seems to show plant-side resistance to be important. Models are usually based on the assumption that POP uptake occurs through the lipophilic cuticle which covers aerial surfaces of plants. However, some authors have recently attached greater importance to the stomatal route of entry into the leaf for gas phase compounds. There is a need for greater mechanistic understanding of air-plant exchange and the 'scaling' of factors affecting it. The review also suggests a number of key variables that researchers should measure in their experiments to allow comparisons to be made between studies in order to improve our understanding of what causes any differences in measured data between sites. (C) 2003 Elsevier Ltd. All rights reserved

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