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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 radionuclide is a radioisotope [22].?

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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 quartzites (Keyword) returned 18 results for the whole karstbase:
Showing 16 to 18 of 18
STYLES OF HYPOGENE CAVE DEVELOPMENT IN ANCIENT CARBONATE AREAS OVERLYING NON-PERMEABLE ROCKS IN BRAZIL AND THE INFLUENCE OF COMPETING MECHANISMS AND LATER MODIFYING PROCESSES, 2009, Augusto S. Auler

A significant proportion of the karst areas in Brazil develop over ancient cratonic or tectonically stable zones overlying Precambrian quartzites or Archaean crystalline basement (granite, gneiss, schist). In such settings, due to the low transmissivity and highly anisotropic nature of the bedrock, major groundwater flow of regional scale tends to be restricted, and diffuse ascending cross-formational flow into the carbonate is limited to a few favourable input zones. Nevertheless, caves displaying hypogene features occur in several areas, although few contain the full suite of speleogenetic forms commonly found in “classic” better studied areas of Europe and North America. Major known hypogene caves in Brazil tend to be located in zones bordering the more stable cratonic areas, such as in Vazante and Toca da Boa Vista karst areas, where fault zones are likely candidates for providing ascending flow paths towards the carbonate. The absence of transmissive beds above the carbonate limits the existence of outflow routes. Brazilian hypogene caves develop in mostly horizontally bedded or gently dipping bedrock and typically do not display the three-dimensional character of many hypogene caves elsewhere. The speleogenetic role of competing mechanisms such as sulphuric acid dissolution due to pyrite oxidation and condensation corrosion tend to overprint original forms as well as produce similar convergent features.


Sandstone caves on Venezuelan tepuis: Return to pseudokarst?, 2011, Aubrecht R. , Lanczos T. , Gregor M. , Schlogl J. , Smida B. , Liscak P. , Brewercarias C. H. , Vlek L.

Venezuelan table mountains (tepuis) host the largest arenite caves in the world. The most frequently used explanation of their origin so far was the "arenization" theory, involving dissolution of quartz cement around the sand grains and subsequent removing of the released grains by water. New research in the two largest arenite cave systems - Churi-Tepui System in Chimanta Massif and Ojos de Cristal System in Roraima Tepui showed that quartz dissolution plays only a minor role in their speleogenesis. Arenites forming the tepuis are not only quartzites but they display a wide range of lithification and breakdown, including also loose sands and sandstones. Speleogenetic processes are mostly concentrated on the beds of unlithified sands which escaped from diagenesis by being sealed by the surrounding perfectly lithified quartzites. Only the so-called "finger-flow" pillars testify to confined diagenetic fluids which flowed in narrow channels, leaving the surrounding arenite uncemented. Another factor which influenced the cave-forming processes by about 30% was lateritization. It affects beds formed of arkosic sandstones and greywackes which show strong dissolution of micas, feldspars and clay minerals, turning then to laterite ("Barro Rojo"). The main prerequisite to rank caves among karst phenomena is dissolution. As the dissolution of silicate minerals other than quartz appears to play not only a volumetrically important role but even a trigger role, these arenitic caves may be ranked as karst.


Dokumentation von zwei Quarzithhlen am Roraima Tepui (Brasilien, Guyana) , 2011, Plan L. , Hlzel M. , Auler A.
The Gran Sabana extends over the area between the Amazonas and Orinoco River in the northern part of South America. There about hundred table mountains (locally named Tepuis) are rising above the wet savannah plain. One of these, the Roraima Tepui, is situated at the triple border junction of the states of Brazil, Guyana and Venezuela. The plateau is built up of sandstones and quartzites of palaeoproterozoic age (c. 1.9 Billion years). Several caves which have mainly developed due to mechanical erosion of not or just partly lithified sandstone layers have been explored. The aim of a Brazilian Austrian expedition in November 2010 was to visit caves in the southern part of the Roraima Tepui and search for new caves in the less accessible northern part. The Cueva Ojos de Cristal (or Sistema Roraima Sur) was visited. With a mapped length of 16.1 km it is the biggest quartzite cave known in the world. Two caves were mapped, the Hotel Coati and the Lake Gladys Cave, which are the highest lying documented caves of Guyana and Brazil respectively. The Hotel Coati is situated in the north of the Tepui and is a cave often used as a bivouac. It is a shaft, acting as ponor, which is accessible through galleries aligned at rectangularly arranged fissures. North of that cave, in the Guyanese part, the single lake on the plateau, the Lake Gladys is situated at 2665 m a.s.l. There, the Lake Gladys Cave with a total length of 68 m is draining the lake. The entrance lies behind a boulder fall and water disappears into a sump. At the Roraima Tepui there are other not docu - mented objects so far, as the shaft ponor El Fosso (The Pit). Even though no major systems were found during this short expe - dition, the potential of finding further caves in the northern part seems still good.

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