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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 elutriation is a washing process by decantation with water [16].?

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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 rhizoliths (Keyword) returned 4 results for the whole karstbase:
PALUSTRINE CARBONATES AND THE FLORIDA EVERGLADES - TOWARDS AN EXPOSURE INDEX FOR THE FRESH-WATER ENVIRONMENT, 1992, Platt N. H. , Wright V. P. ,
Palustrine carbonates are shallow fresh-water deposits showing evidence of subaqueous deposition and subaerial exposure. These facies are common in the geological record. The intensity of modification is highly variable depending on the climate and the length of emergence. Palustrine limestones have previously been interpreted as marginal lacustrine deposits from fluctuating, low-salinity carbonate lakes, but several problems remain with existing facies models: 1) palustrine carbonates possess a lacustrine biota but commonly display fabrics similar to those of calcretes and peritidal carbonates; 2) the co-occurrence of calcrete horizons and karst-like cavities is somewhat unusual and appears to indicate contemporaneous carbonate precipitation and dissolution in the vadose zone; 3) the dominance of gray colors indicates water-saturation, apparently inconsistent with the evidence for strong desiccation overprint; 4) profundal lake deposits are generally absent from palustrine sequences, and sublittoral facies commonly make up only a small proportion of total thicknesses; 5) no good modem analogue has been identified for the palustrine environment. Analogy with the Florida Everglades suggests a re-interpretation of palustrine limestones, not as pedogenically modified lake margin facies but as the deposits of extensive, very shallow carbonate marshes. The distribution of environments in the Everglades is determined by the local hydrology, reflecting the control of seasonal water-level fluctuations and topography. Climate and topography were the main controls on deposition of ancient palustrine carbonates. As in peritidal sequences, aggradational cycles are capped by a range of lithologies (evaporites, desiccation and microkarst breccias, calcretes, lignite or coal horizons etc.), permitting interpretation of the climate. Careful analysis of lateral facies variations may permit reconstruction of subtle topography. Consideration of the Florida Everglades as a modem analogue for the palustrine environment has suggested the development of an exposure index for fresh-water carbonates

Calcrete morphology and karst development in the Upper Old Red Sandstone at Milton Ness, Scotland, 2000, Balin Df,
The Upper Old Red Sandstone at Milton Ness, Scotland, is notable for its excellent preservation of calcrete textures, which are comparable with some of the best Quaternary examples. It is also significant for the implications that can be drawn from the association between karst and calcrete, with this example interpreted to have formed entirely within a semi-arid environment. Karst cavities were developed in a mature hardpan calcrete, generated in sandy fluvial sediments with associated aeolian deposits. Subsequent to karst cavity generation, clasts derived from the subaerially exposed hardpan were locally transported and deposited as a laterally traceable bed connecting the tops of all the cavities. Both this bed and the karst infills were subsequently recalcretized in the final phase of the profile's evolution. Although calcrete-karst associations often are interpreted as the alternation between semi-arid and humid climates, respectively, this example is interpreted to be a result of water accumulating on the nearly impervious hardpan surface under fairly constant semiarid conditions, evidenced by the recalcretization of both the karst infill and the calcrete-derived breccia ( boulder calcrete'). Additional substrate modification also has taken place by plant roots; the remarkable development of rhizoliths in these Old Red Sandstone sediments should emphasize the need to consider plant influence on other non-marine rocks of post-Silurian age

Quantification of Macroscopic Subaerial Exposure Features in Carbonate Rocks, 2002, Budd Da, Gaswirth Sb, Oliver Wl,
The macroscopic features that characterize subaerial exposure surfaces in carbonates are well known, but their significance has not been quantitatively evaluated. This study presents such an analysis in the lower Oligocene Suwannee Limestone of west-central Florida. Eleven cores were point counted on a foot-by-foot basis for the abundance of caliche, rhizoliths, karst breccia, open vugs, infiltrated sediment, fractures, and pedogenic alteration. These features occur at and below intraformational exposure surfaces, which represent hiatuses estimated at 104 to 105 years, and an uppermost sequence-bounding unconformity representing 0.5 Myr, as revealed by Sr-isotope data. Statistical analyses of the point-count data reveal only a few significant relationships. (1) The hierarchy of exposure surfaces, and by inference duration of exposure, is differentiated only at a marginally significant level by sediment-filled vugs preferentially associated with the sequence boundary. Duration of exposure did not have a significant impact on the relative abundance of all other features. (2) Proximity (< 5 ft; 1.5 m) to any exposure surface is indicated only by rhizoliths, caliche, and pedogenic alteration, whereas karst breccia is preferentially found distal (> 5 ft) to both types of surfaces. Fractures, open vugs, and infiltrated sediment show no proximal or distal preference for either type of surface. (3) Depositional texture has no statistically significant affect on the presence or abundance of the exposure features, with the exception that rhizoliths and open vugs are preferentially more abundant in packstones relative to grainstones. This is interpreted to be the result of a soil-moisture effect. Factor analysis defines four factors that explain 46% to 52% of the total variance in the abundance data relative to the sequence boundary and the intraformational surfaces, respectively. The loading of each exposure feature on each factor is the same with respect to both types of surfaces, which is further evidence that the abundance of exposure features is independent of duration of exposure. Factor 1 is interpreted to be the amplitude of base-level changes and controls the abundance of karst breccia. Factor 2 is interpreted to be abundance of vegetation and relates to the abundance of rhizoliths and fractures. Factor 3 is interpreted to be a combination of soil-zone PCO2 and the availability of water and affects the abundance of pedogenic overprinting, caliche, and open vugs. Factor 4 is stratigraphic proximity to the sequence boundary, which controls the presence of sediment-filled voids. The amount of uncorrelated unique variance associated with infiltrated sediments, pedogenic overprinting, caliche, and open vugs is large (> 60%), meaning that feature abundance is also influenced by other unidentified site-specific factors. These results demonstrate that quantifying the abundance of macroscopic subaerial exposure features in limestones has the potential to yield more insight into the significance of those features than a mere qualitative assessment. This is particularly true when assessing the potential role of the many variables that can affect the development of these features

Lower Miocene gypsum palaeokarst in the Madrid Basin (central Spain): dissolution diagenesis, morphological relics and karst end-products, 2002, Rodriguezaranda J. P. , Calvo J. P. , Sanzmontero M. E. ,
The Miocene sedimentary record of the Madrid Basin displays several examples of palaeokarstic surfaces sculpted within evaporite formations. One of these palaeokarstic surfaces represents the boundary between two main lithostratigraphic units, the Miocene Lower and Intermediate units of the Madrid Basin. The palaeokarst formed in lacustrine gypsum deposits of Aragonian age and corresponds to a surface palaeokarst (epikarst), further buried by terrigenous deposits of the overlying unit. Karst features are recognized up to 5.5 m beneath the gypsum surface. Exokarst and endokarst zones are distinguished by the spatial distribution of solution features, i.e. karren, dolines, pits, conduits and caves, and collapse breccias, sedimentary fills and alteration of the original gypsum across the karst profiles. The development of the gypsum palaeokarst began after drying out of a saline lake basin, as supported by recognition of root tubes, later converted to cylindrical and funnel-shaped pits, at the top of the karstic profiles. The existence of a shallow water table along with low hydraulic gradients was the main factor controlling the karst evolution, and explains the limited depth reached by both exokarst and endokarst features. Synsedimentary fill of the karst system by roughly laminated to massive clay mudstone with subordinate carbonate and clastic gypsum reflects a punctuated sedimentation regime probably related to episodic heavy rainfalls typical of arid to semi-arid climates. Duration of karstification is of the order of several thousands of years, which is consistent with previous statements that gypsum karstification can develop rapidly over geologically short time periods

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