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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 helictite is 1. generally small variety of stalactitic calcite growth that is twisted and contorted with no apparent regard for gravity. helictites form on cave walls, ceilings, and on stalactites. the growth develops as seepage water loses carbon dioxide from near its tip, having been supplied to that point by capillary action through a fine central canal. the helictite shape is created by crystal lattice distortion and crystal form changes within the calcite, but what causes these is uncertain. impurities may plan a role, and rare groups of parallel growing helictites may be wind-guided [9]. 2. irregular, twiglike, crystalline growths with varying orientations but often in crystal continuity, formed in caves by precipitation from bicarbonate solutions [20]. 3. a curved or angular twiglike lateral projection of calcium carbonate having a tiny central canal, found in caves [10]. also known as eccentric anemolite [20]; eccentric stalactite. synonyms: (french.) excentrique; (german.) exzentrisch gekrummter, tropfstein, excentriques; (greek.) stalaktits akanonistos; (italian.) stalattiti anomale, eccentiche; (spanish.) estalactita excentrica; (turkish.) duzensiz sarkit; (yugoslavian.) heliktit. related to curtain, dripstone, speleothem.?

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

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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;
See all featured articles from other geoscience journals

THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB
Computers & Geosciences, 1996, Vol 22, Issue 4, p. 419-424
PC-based two-dimensional discrete Fourier transform programs for terrain analysis
Abstract:
A two-dimensional Fast Fourier Transform (2D-FFT) program written in C language was developed for the personal computer with the specific purpose of extracting periodicities from digital elevation model (DEM) data. The program generates the individual frequency pairs, the coefficients representing the amplitudes of the cosine and sine waves, the angle the wavefront makes in the terrain, the wavelength, the power of the wave, the percent contribution the wave makes to the overall landscape, and finally the overall percentage of variance accounted for by the model. The landscape can be reconstructed based on the number of significant waveforms extracted. Generalizations on the spatial trends of the terrain therefore can be made. The Fourier analysis provides insight to the nature and complexity of the terrain. An application of the program to the karst landscape of Manati, Puerto Rico is illustrated. Copyright (C) 1996 Elsevier Science Ltd