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Enviroscan Ukrainian Institute of Speleology and Karstology


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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 river bed is the channel of a river covered by water [16].?

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.
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 membrane (Keyword) returned 5 results for the whole karstbase:
The role of groundwater in eutropication of a lake in glacial outwash terrain., 1976,
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Lee David Robert
The nutrient contribution of groundwater in glacial outwash terrain was evaluated at Lake Sallie in north-central U.S.A. (4646' N., 95 54' W.). Groundwater entering the lake was collected with seepage meters consisting of bottomless cylinders vented to a thin membrane bag. A theoretical flow net and comparison of nutrient concentrations in well and seepage water indicated that seepage meters can be used in high velocity discharge areas to obtain site-specific water samples of groundwater for nutrient analyses. Based on an average value of 0.25 mg/l PO4, groundwater inflow along an 800 km segment of shoreline transported 37 kg of phosphorus per year into the lake. Groundwater inflow was nitrate rich along shoreline adjacent so land used for agriculture and lakeside septic tanks, but there was no apparent pattern regarding land use and phosphorus content of groundwater inflow. A nearby eutrophic lake was a suspected source of phosphorus in groundwater inflow. Because surface flow has carried large quantities of nitrogen and phosphorus into this lake, its present eutrophic condition cannot be attributed to nutrient influx by groundwater. However, groundwater nutrient influx could be highly significant in other lakes where surface nutrient influx is small.

Road and bridge construction across gypsum karst in England, 2002,
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Cooper Ah, Saunders Jm,
Gypsum karst problems in the Permian and Triassic sequences of England have caused difficult conditions for bridge and road construction. In Northern England, the Ripon Bypass crosses Permian strata affected by active gypsum karst and severe subsidence problems. Here, the initial borehole site investigation for the road was supplemented by resistivity tomography studies. The roadway was reinforced with two layers of tensile membrane material within the earth embankment. This will prevent dangerous catastrophic collapse, but will allow sagging to show where problems exist. The River Ure Bridge was constructed across an area of subsidence pipes filled with alluvial deposits. It was built with extra strength, larger than normal foundations. If one pier fails, the bridge is designed for adjacent arches to span the gap without collapse. The bridge piers are also fitted with electronic load monitoring to warn of failure. In the Midlands area of England, road construction over Triassic gypsum has required a phase of ground improvement on the Derby Southern Bypass. Here, the gypsum caps a hill where it was formerly mined; it dips through a karstic dissolution zone into an area of complete dissolution and collapse. The road and an associated flyover were built across these ground conditions. A major grouting program before the earthworks began treated the cavities in the mine workings and the cavernous margin of the gypsum mass. Within the karstic dissolution zone, gypsum blocks and cavities along the route were identified by conductivity and resistivity geophysical surveys, excavated and backfilled. In the areas of complete dissolution and collapse, the road foundation was strengthened with vibrated stone columns and a reinforced concrete road deck was used. (C) 2002 S. Yamamoto. Published by Elsevier Science B.V on behalf of NERC. All rights reserved

Iron Oxide and Calcite Associated with Leptothrix sp. Biofilms within an Estavelle in the Upper Floridan Aquifer, 2011,
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Florea Lee J. , Stinson Chasity L. , Brewer Josh, Fowler Rick, Kearns B Joe, Greco Anthony M.

In Thornton’s Cave, an estavelle in west-central Florida, SEM, EDS, and XRD data reveal biofilms that are predominantly comprised of FeOOH-encrusted hollow sheaths that are overgrown and intercalated with calcite. Fragments of this crystalline biofilm adhere to the walls and ceiling as water levels vary within the cave. Those on the wall have a ‘cornflake’ appearance and those affixed to the ceiling hang as fibrous membranes. PCR of DNA in the active biofilm, combined with morphologic data from the tubes in SEM micrographs, point to Leptothrix sp., a common Fe-oxidizing bacteria, as the primary organism in the biofilm. Recent discoveries of ‘rusticles’ in other Florida caves suggest that Fe-oxidizing bacteria may reside elsewhere in Florida groundwater and may play a role in the mobility of trace metals in the Upper Florida aquifer.
SEM micrographs from two marble tablets submerged for five months, one exposed to microbial activity and a second isolated from microbial action, revealed no visible etchings or borings and very limited loss of mass. EDS data from the electron micrographs of the unfiltered tablet document the same FeOOH-encrusted hollow sheaths and similar deposits of calcite as seen in the ‘cornflakes’. These results, combined with water chemistry data imply that the biofilm may focus or even promote calcite precipitation during low-water level conditions when CO2 degasses from the cave pools.


Evaluation of Strategies for the Decontamination of equipment for Geomyces destructans, the Causative Agent of the White-Nose Syndrome (WNS), 2013,
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Shelley V. , Kaiser S. , Shelley E. , Williams T. , Kramer M. , Haman K. , Keel K. , Barton H. A.

 

White-nose syndrome is an emerging infectious disease that has led to a
dramatic decline in cave-hibernating bat species. White-nose syndrome is caused by the
newly described fungal pathogen Geomyces destructans, which infects the ear, muzzle,
and wing membranes of bats. Although the exact mechanism by which the fungus causes
death is not yet understood, G. destructans leads to a high mortality rate in infected
animals.While the primary mechanism of infection appears to be bat-to-bat transfer, it is
still unclear what role human activity may play in the spread of this pathogen. Here we
evaluate the effectiveness of decontamination protocols that can be utilized by
speleologists to reduce the likelihood of spreading this dangerous pathogen to naı¨ve
bats or uninfected hibernacula. Our results show that pre-cleaning to remove muds and/
or sediments followed by the use of commercially available disinfectants can effectively
remove G. destructans from caving fabrics. Alternatively, immersion in water above
50 uC for at least 20 minutes effectively destroys the fungal spores. These results have
allowed the development of a decontamination protocol (http://www.fws.gov/
WhiteNoseSyndrome/cavers.html) that, when appropriately followed, can greatly
reduce the likelihood of the human mediated transfer of G. destructans from an
infected to uninfected site.


COVER-COLLAPSE SINKHOLE DEVELOPMENT IN THE CRETACEOUS EDWARDS LIMESTONE, CENTRAL TEXAS, 2013,
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Hunt B. B. , Smith B. A. , Adams M. T. , Hiers S. E. , Brown N.

Sudden cover-collapse sinkhole (doline) development is uncommon in the karstic Cretaceous-age Edwards limestone of central Texas. This paper presents a case-study of a sinkhole that formed within a stormwater retention pond (SWRP) in southwest Austin. Results presented include hydrogeologic characterizations, fate of stormwater, and mitigation of the sinkhole. On January 24, 2012, a 11 cm (4.5 in) rainfall filled the SWRP with about 3 m (10 ft) of stormwater. Subsequently, a sinkhole formed within the floor of a SWRP measuring about 9 m (30 ft) in diameter and 4 m (12 ft) deep. About 26.5 million liters (7 million gallons) of stormwater drained into the aquifer through this opening. To determine the path, velocity, and destination of stormwater entering the sinkhole a dye trace was conducted. Phloxine B was injected into the sinkhole on February 3, 2012. The dye was detected at one well and arrived at Barton Springs in less than 4 days for a minimum velocity of 2 km/day (1.3 mi/day).Review of pre-development 2-foot topographic contour and geologic maps reveals that the SWRP was built within a broad (5,200 m2; 6 acre), shallow depression bounded by two inferred NE-trending fault zones. Photographs taken during SWRP construction showed steep west-dipping bedrock in the northern SWRP wall. Following collapse of the sinkhole, additional hydrogeologic characterization included excavation to a depth of 6.4 m (21 ft), surface geophysics (resistivity), and rock coring. Geologic materials consisted mostly 89of friable, highly altered, clayey limestone consistent with epikarst in-filled with terra rosa providing a cover of the feature. Dipping beds, and fractured bedrock support proximity to the mapped fault zone. Geophysics and surface observations suggested a lateral pathway for stormwater flow at the junction between the wet pond’s impermeable geomembrane and compacted clay liner for the retention pond. The collapse appears to have been caused by stormwater down-washing poorly consolidated sediments from beneath the SWRP and into a pre-existing karst conduit system.

Mitigation of the sinkhole included backfill ranging from boulders to gravel, a geomembrane cover, and reinforced concrete cap. Additional improvements to the SWRP included a new compacted clay liner overlain by a geomembrane liner on the side slopes of the retention pond.


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