Community news

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 paleokarst is 1. a karstified rock or area that has been buried by later sediments; in some places, ancient caves have been completely filled by the later sediments [10]. 2. a decoupled contemporary system that has experienced tectonic subsidence and lie unconformably beneath clastic cover rocks, occasionally becoming exhumed and re-integrated into the active system [17]. 3. a karst formed in the past under an earlier erosion cycle and often in remote geological times. the karst is preserved by burial or suspension of karstification processes [20]. 4. a karstified surface and the karst features associated with it, such as caves, that have been buried by younger rocks. paleokarstic features at various scales may be recognized within most carbonate successions. more rarely they may be reexposed (exhumed) by the effects of later uplift and erosion [9]. synonyms: (french.) paleokarst; (german.) palaokarst, fobiler karst; (greek.) paleokarst; (italian.) paleocarsismo, carsismo fossile; (russian.) paleokarst; (spanish.) paleokarst; (turkish.) eski karst; (yugoslavian.) paleokrs, paleokras, paleokarst. see also buried karst.?

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

What is Karstbase?

Search KARSTBASE:

keyword
author

Browse Speleogenesis Issues:

KarstBase a bibliography database in karst and cave science.

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;
See all featured articles from other geoscience journals

Search in KarstBase

Your search for shield (Keyword) returned 21 results for the whole karstbase:
Showing 16 to 21 of 21
The Earth Has a Future, 2006, Dutch Si,
An alternative to visualizing geologic time by looking into the past is to look into the future. Even geologically short future time scales completely outstrip our ability to forecast changes in human society, whereas most geologic changes in the same time will be modest. Many events that are infrequent on a human time scale, such as earthquakes and volcanic eruptions, become commonplace on longer time scales, and events that have not occurred in recorded history, such as major ice ages, large meteor impacts, giant pyroclastic eruptions, or collapses of Hawaiian shield volcanoes, become almost inevitable in a million years

Eisdickenmessungen in alpinen Hhlen mit Georadar, 2007, Behm M. , Hausmann H.
Ground penetrating radar (GPR) has been used to determine the ice thickness at several locations in three alpine ice caves Eisriesenwelt, 1511/24, Salzburg; Dachstein-Mammuthhle, 1547/9, Upper Austria; Dachstein-Rieseneishhle, 1547/17, Upper Austria). It could be shown that shielded antennas with relatively high frequencies (500 MHz) are sufficient to penetrate the ice up to 15 m depth. 3D layouts (crossing profiles) were necessary to delineate the subsurface in detail and to verify that certain reflections in the radargramm sections originate from the subsurface. In almost all radargramm sections, the lower boundary of the ice body is identified by the onset of strong and sharp reflections. We attribute this to either increased humidity at the ice rock contact (due to melting) or to a sedimentary layer between ice and rock. Pronounced layering of the ice body itself is clearly seen at some locations, which may results from alternating air content. The maximum thickness is 7.5 m in Eisriesenwelt (location Eispalast), 6 m in the Dachstein-Mammuthhle (location Saarhalle) and 15 m in the Dachstein-Rieseneishhle (location Tristandom).

Dramatic increase in late Cenozoic alpine erosion rates recorded by cave sediment in the southern Rocky Mountains, 2010, Refsnider, Kurt A.

Apparent increases in sedimentation rates during the past 5 Ma have been inferred at sites around the globe to document increased terrestrial erosion rates, but direct erosion rate records spanning this period are sparse. Modern and paleo-erosion rates for a small alpine catchment (3108 m above sea level) in the Southern Rocky Mountains are measured using the cosmogenic radionuclides (CRNs) 10Be and 26Al in cave sediment, bedrock on the overlying landscape surface, and coarse bedload in a modern fluvial drainage. The unique setting of the Marble Mountain cave system allows the inherited erosion rates to be interpreted as basin-averaged erosion rates, resulting in the first CRN-based erosion rate record from the Rocky Mountains spanning 5 Myr. Pliocene erosion rates, derived from the oldest cave sample (4.9 ± 0.4 Ma), for the landscape above the cave are 4.9 ± 1.1 m Myr− 1. Mid Pleistocene erosion rates are nearly an order of magnitude higher (33.1 ± 2.7 to 41.3 ± 3.9 m Myr− 1), and modern erosion rates are similar; due to the effects of snow shielding, these erosion rate estimates are likely higher than actual rates by 10–15%. The most likely explanation for this dramatic increase in erosion rates, which likely occurred shortly before 1.2 Ma, is an increase in the effectiveness of periglacial weathering processes at high elevations related to a cooler and wetter climate during the Pleistocene, providing support for the hypothesis that changes in late Cenozoic climate are responsible for increased continental erosion.


Speleothems: General Overview, 2012, White, William B.

Speleothems are secondary mineral deposits formed in caves by flowing, dripping, or seeping water. The most commonly occurring minerals are calcite, aragonite, and gypsum although many other minerals have been found in speleothems. The shapes of speleothems are determined by a competition between the dynamics of the water and the crystal growth habits of the constituent minerals. Stalactites, stalagmites, flowstone, and other speleothems deposited from dripping for flowing water take shapes dictated by the details of the flow behavior. Helictites, anthodites, and gypsum flowers formed from seeping water and various pool deposits take shapes dictated by the habit of crystal growth. Tan, orange, and brown colors common to calcite speleothems and also their luminescence under ultraviolet light is due to inclusion of humic and fulvic acid from overlying soils. Speleothems are also found in lava tubes.


Geomorphogenesis of astructural slopes of the Inner Range of the Mountainous Crimea: the role of hypogenic karst in the formation and retreat of cliffs, 2012, Tymokhina . . , Klimchouk A. B. , Amelichev G. M.

In geomorphogenesis of the fore-mountain region, a leading role is played by the processes of dismemberment of «shielding» limestone layers of the monoclinal stratified structure, and slope processes in the intervals of rocky limestone utcrops. Their main pre-condition for the latter is hypogene karst development which preceded the modern relief and controlled its formation. Karstified fracture-karst zones, 100 to 400 m wide, in the Cretaceous-Paleogene strata controlled the entrenchment of valleys in the limestone layers. The basic elements of hypogenic karst structures, which forms their spatial framework, are subvertical
fracture-karst conduits (karst «rifts»). Dissection of limestone layers along vertical fracture-karst rift conduits initially set the cliff-like shape of valleys slopes, and presence of such rift conduits in the rear of cliffs of already incised valleys determines the mechanisms of cliff retreat, with the maintenance of verticality, and controls position and configuration of segments of cliffs. A dominant slope process in the intervals of limestones is block toppling, whereas blocks become separated mainly along remaining
fracture-karst conduits in rearward parts of cliffs. Hypogenic sculptural morphology is displayed in the exposed walls of the fracture-karst conduits, which determines the originality and nomenclature of morphology of limestone cliffs of the Inner Range. In those areas of slopes where position of cliffs has stabilized for considerable time due to absence of new lines of block detachment in the rear, weathering becomes a significant process in the morphogenesis of surfaces. Slopes lose their verticality and acquire
the smoothed rims. Specific hypogenic sculptural morphology of cliffs is being destroyed on such slopes. The finding about control of slope processes in limestones by hypogenic fracture-karst structures gives new important criteria for the slope condition assessment and prognosis of hazardous collapses and rockfalls in the limits of the Internal Range 


HYPOGENIC SPELEOGENESIS IN THE CRIMEAN FORE-MOUNTAINS (THE BLACK SEA REGION, SOUTH UKRAINE) AND ITS ROLE IN THE REGIONAL GEOMORPHOLOGY, 2013, Klimchouk A. , Amelichev G. , Tymokhina E. , Tokarev S.

 

The leading role in the geomorphic development of the Crimean fore-mountain region is played by the processes of dismemberment of “shielding” limestone layers of the monoclinal stratified structure through valley entrenchment, and by further retreat of vertical rocky outcrops via block-toppling mechanism. These processes are guided by the presense of hypogene karst structures, whose formation preceded the modern relief. Karstified fracture-karst zones, 100 to 400 m wide, in the Cretaceous-Paleogene strata controlled the entrenchment of valleys in the limestone layers. The basic elements of hypogenic karst structures, which form their spatial framework, are sub-vertical fracture-karst conduits (karst “rifts”). Denudational opening of vertical fracture-karst rift conduits in limestone layers set the cliff-like shape of valleys slopes, and presence of such rift conduits in the rear of cliffs of already incised valleys determines the block-toppling mechanisms of slope retreat. This maintains the verticality of cliff segments in the cuesta ridge and controls their position. Hypogenic sculptural morphology is extensively displayed in the exposed walls of cliffs (former conduit walls), which determines the originality and nomenclature of morphology of limestone cliffs of the Inner Ridge. In those areas of slopes where position of cliffs has stabilized for considerable time due to absence of new lines of block detachment in the rear, weathering becomes a significant process in the morphogenesis of surfaces. The abundance, outstanding expression, preservation and accessibility of relict hypogene karst features in the extensive cuesta cliffs of the Inner Ridge makes the region the foremost one for studying regularities of hypogene solution porosity development, the process currently ongoing in the adjacent artesian basin of the Plain Crimea.


Results 16 to 21 of 21
You probably didn't submit anything to search for