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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 aquifere epikarstique is see epikarst zone.?

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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 scree (Keyword) returned 39 results for the whole karstbase:
Showing 31 to 39 of 39
HYDRAULIC PROPERTIES OF CARBONATE ROCKS FROM SLOVAKIAN BOREHOLE DATABASE, 2010, Malk P. & vasta J.
Using archival hard copy records on 22,922 wells and hydrogeological boreholes, maintained since 1950s on the territory of Slovak Republic, a spatial database was developed. If possible, each borehole was linked to a certain aquifer or aquifer lithological type, according to its screened interval. Wells with ambiguous position of open casing were excluded from further processing to obtain distinct relation of pumping rate to lithology. Using stored records of hydraulic tests, each pumping rate was processed to obtain uniformly calculated standard specific capacity. These values were subsequently used to reinterpret hydraulic parameters. Based on standardized specific capacity data, estimates of transmissivity (T; in m2s-1) and hydraulic conductivity (K; in ms-1) for each well were calculated and linked to corresponding aquifer type. From these, hydraulic properties of limestones (238 boreholes), dolomites (463 boreholes) and granitoid rocks (96 boreholes) are compared. As anticipated, geometrical mean of transmissivity was low for granitoids (6.5110-5 m2s-1) and one order of magnitude higher for limestones (6.1610-4 m2s-1), due to its enhancement by karstification. The highest observed value of mean transmissivity, two times higher than that found for limestones, was obtained for dolomitic aquifers (1.0410-3 m2s-1). Dolomitic aquifers also show the highest median values of hydraulic conductivity (3.2110-5 ms-1), in one order of magnitude higher than granitoids (2.1010-6 ms-1) and three times higher than limestones (9.4510-6 ms-1). In comparison with limestones, dolomites seem to be slightly more homogeneous in aquifer properties; also several lithological types there show similarities in both T and K. Some limestone lithofacies (Steinalm and Raming), seem to have lower transmissivity and hydraulic conductivity comparing to other limestones types (Dachstein, Gutenstein, Wetterstein). The data on hydraulic properties of all these hard rocks show lognormal statistical distribution and high heterogeneity.

Vascular plant biodiversity richness and endemo relictness of the karst mountains Prenj-Čvrsnica-Čabulja in Bosnia and Herzegovina (W. Balkan) , 2011, Redhić, Sulejman, Barudanović, Senka, Trakić, Sabina, Kulijer Dejan
The complex of karstic mountains Prenj-Čvrsnica and Čabulja in Herzegovina (w. Balkan) is characterized by high level of both geomorphology and biodiversity richness. This has been confirmed by a research of plant communities, their structure and dynamics, which took place throughout several seasons from 2005 to 2008. In the investigated area the vegetation cover, as a reliable indicator for specific karstic circumstances, is being differentiated in a great number of syntaxa (plant communities) that encompass over 2,500 vascular plants. On the surface of about 100,000 ha identified were up to 236 plant associations, 116 alliances and 63 vegetation orders that belong to 34 classes. This amounts 34% of total of vegetation classes at the European level and 100% of so far known vegetation classes in Bosnia and Herzegovina, over 80% of classes at the level of Montenegro and Croatia.There have been identified nearly 450 endemic and relict species, which is why most of the identified communities are endemic and relict ones, not only at the level of association but also at the level of higher syntaxonomic categories, such as alliance and order. The highest diversity level characterizes those communities that make a direct contact with the calcareous geological foundation either in rock crevices or screes on limestone. That high level of floristic and vegetation richness places this area among the most diverse areas both in Europe and whole Mediterranean.That high level of floristic and vegetation richness places this area among the most diverse areas both in Europe and whole Mediterranean. Such pattern of vegetation (syntaxonomy) and floristic diversity confirms the unique role of dinaric-herzegovina karst as a complex of unrepeatable ecological factors on global scale.

Paleokarst Breccia-Pipe Reservoir Analogue, Carboniferous, Svalbard, 2011, Wheeler Walter, Tveranger Jan, Lauritzen Steinerik, Heincke Björn, Rossi Guiliana, Allroggen Niklas, Buckley Simon

Upwards-propagating collapse pipes typically form sinkholes where they meet the land surface. Renewed dissolution of breccia in ancient pipes can have a similar effect. For these cases, probability-based models of sinkhole hazard are closely related to the expected mature architecture of the collapse-pipe field. We present a case study of the architecture of a square-kilometre field of collapse-pipes from the Carboniferous-Permian in which the pipes are documented in outcrop and using shallow geophysical methods.

The study site is located on the Wordiekammen plateau in the Carboniferous Billefjorden half-graben basin on Spitsbergen. Cliffs bounding the plateau expose breccia pipes cutting a gently-dipping 200-m-thick series of platform carbonates, in turn underlain by stratiform breccias and residual pods of gypsum. Many of the breccia pipes are tall (>250 m) and postdate several shallow karstification episodes. Most pipes are inferred not to have reached the surface based on a lack of terrigenous material and fluvial structure, although several pipes show indications of such surface communication. Although the pipes are generally attributed to gypsum dissolution, a deep carbonate karstification event is inferred based on high temperature calcite cement, and burial dehydration of gypsum, may also have contributed to void formation.

On the plateau top the collapse pipes are obscured by thick scree, thus km-scale size and spacing data for the pipes and faults was collected by mapping the bedrock with 2D ground-penetrating radar (GPR). GPR profiles were acquired on a grid with 25-meter line spacing, using 50 MHz antennas and achieving 30-40 m penetration. Breccia bodies were identified by steep-sided zones of complex diffraction patterns interrupting bedding-related continuous reflections. Two pipes were further studied in 3D using high-resolution GPR, tomographic seismic and geo-electric. These geophysical data were merged into a comprehensive 3D framework including helicopter-borne lidar and photo scans of the plateau rim geology, thus allowing an integrated visualization and interpretation of the different datasets. The GPR data show the breccia pipes to be slightly oblate with diameters ranging from 20 to over 100 m; 60 meters is a typical value. Approximately 10 pipes are identified in cliff-side outcrops bordering the GPR area, whereas 30 more are identified within the plateau by the GPR data. The GPR volume lies about 200 m above the pipe base, hence the pipe-length frequency-distribution data are incomplete. The strata are cut by small-offset (<5m) faults related to collapse processes and larger-offset faults related to regional basin extension. The breccia pipe field appears to be delimited by these more regional faults, in turn inferred to control the thickness of syn-rift gypsum and/or the hydrology of its dissolution. Collapse breccia pipes form strong vertical heterogeneities in rock properties such as porosity and permeability, matrix density, cement, mechanical strength and lithology, affecting fluid-flow characteristics on a meter to hundred-meter scale. It is rare that pipe fields are well exposed at the kilometre scale. Although some scaling data can be obtained from 3D oil-industry seismic reflection data but the resolution insufficient to visualize critical details. The outcrop combination of seismic, electric and geologic techniques facilitates the interpretation of 3D facies architectures and by proxy porosity-permeability relationships. Studies at the km scale are fundamental for understanding basic karst and collapse processes, and yield petrophysical models that can be applied predictively to natural hazards and groundwater or hydrocarbon exploitation in paleokarst settings.


Cure from the cave: volcanic cave actinomycetes and their potential in drug discovery, 2013, Cheeptham N. , Sadoway T. , Rule D. , Watson K. , Moote P. , Soliman L. C. , Azad N. , Donkor K. K. , Horne D.

Volcanic caves have been little studied for their potential as sources of novel microbial species and bioactive compounds with new scaffolds. We present the first study of volcanic cave microbiology from Canada and suggest that this habitat has great potential for the isolation of novel bioactive substances. Sample locations were plotted on a contour map that was compiled in ArcView 3.2. Over 400 bacterial isolates were obtained from the Helmcken Falls cave in Wells Gray Provincial Park, British Columbia. From our preliminary screen, of 400 isolates tested, 1% showed activity against extended spectrum ß-lactamase E. coli, 1.75% against Escherichia coli, 2.25% against Acinetobacter baumannii, and 26.50% against Klebsiella pneumoniae. In addition, 10.25% showed activity against Micrococcus luteus, 2% against methicillin resistant Staphylococcus aureus, 9.25% against Mycobacterium smegmatis, 6.25% Pseudomonas aeruginosa and 7.5% against Candida albicans. Chemical and physical characteristics of three rock wall samples were studied using scanning electron microscopy and f lame atomic absorption spectrometry. Calcium (Ca), iron (Fe), and aluminum (Al) were the most abundant components while magnesium (Mg), sodium (Na), arsenic (As), lead (Pb), chromium (Cr), and barium (Ba) were second most abundant with cadmium (Cd) and potassium (K) were the least abundant in our samples. Scanning electron microscopy (SEM) showed the presence of microscopic life forms in all three rock wall samples. 16S rRNA gene sequencing of 82 isolates revealed that 65 (79.3%) of the strains belong to the Streptomyces genus and 5 (6.1%) were members of Bacillus, Pseudomonas, Nocardia and Erwinia genera. Interestingly, twelve (14.6%) of the 16S rRNA sequences showed similarity to unidentif ied ribosomal RNA sequences in the library databases, the sequences of these isolates need to be further investigated using the EzTaxon-e database (http://eztaxon-e. ezbiocloud.net/) to determine whether or not these are novel species. Nevertheless, this suggests the possibility that they could be unstudied or rare bacteria. The Helmcken Falls cave microbiome possesses a great diversity of microbes with the potential for studies of novel microbial interactions and the isolation of new types of antimicrobial agents.


Colonization of subterranean habitats by spiders in Central Europe, 2013, Rů, ič, Ka V. , milauer P. , Mlejnek R.

Using data from the Czech Republic, we studied the distribution of spiders in soils, crevice systems, scree and caves, i.e. subterranean habitats at depths spanning from 10 cm to 100 m. In total, we found 161 species. The number of species declines with increasing habitat depth, with a major drop in species richness at the depth of 10 meters. Thirteen species exhibit morphological adaptations to life in subterranean habitats. At depths greater than 10 meters, spider assemblages are almost exclusively composed of troglomorphic species. We propose a hypothesis of evolution of troglomorphisms at spiders during Quaternary climatic cycles.


The effects of UV light on the antimicrobial activities of cave actinomycetes, 2013, Rule Devon, Cheeptham Naowarat

The goal of this study was to determine whether actinomycetes isolated from a volcanic cave in western Canada could produce novel antimicrobial compounds against six multidrug- resistant pathogens when exposed to UV light. One hundred and seventy-six actinomycete strains isolated from Helmcken Falls Cave, Wells Gray Provincial Park, BC, were screened against six pathogens using the “plug assay” in UV light and no light conditions. Of the 176 strains tested, 100 or 57% of the cave actinomycete strains had antimicrobial activities against the pathogens in 124 different instances: 35 instances when exposed to UV and no light, 30 when exposed to UV light, and 59 instances when exposed to no light. The metabolites of six actinomycete strains also lost their antimicrobial activities when exposed to UV light. While the metabolites produced by these strains have yet to be determined, exposure to lighted environments may either deactivate or enhance the antimicrobial activities of cave actinomycete strains. This study represents a confirmation that cave actinomycetes are potential sources of novel antimicrobial compounds and also is the first report of the enhancement of antimicrobial activities of some cave bacteria by exposure to UV light. Further investigation of the role of UV light with respect to activation/deactivation of antimicrobial activities of cave actinomycetes is required.


Molecular divergence and evolutionary relationships among Aemodogryllinae from Southern China, Laos and Thailand (Orthoptera, Rhaphidophoridae), 2013, Valerio Ketmaier, Claudio Di Russo, Mauro Rampini, Nadine Bernhardt, Ralph Tiedemann, Marina Cobolli

In this study we screened for sequence polymorphisms at one mitochondrial (Cytochrome Oxidase subunit I) and one nuclear (Internal Transcribed Spacer 1) gene 33 populations of the cave cricket generaDiestrammena, ParadiestrammenaEutachycines and Paratachycines from Southern China (three Provinces: Jiangxi, Guangdong and Guizhou), Laos and Thailand. Twenty-five of these populations were assigned to the genusDiestrammena, subgenus Gymnaeta, while the remaining eight belonged to the genera Paradiestrammena (3), Eutachycines (3) and Paratachycines(2). The degree of troglomorphosis varies among them; some populations are blind and depigmented, some have fully developed eyes, while some others show intermediate characteristics. Phylogenetic searches carried out on the two gene partitions separately revealed multiple cases of incongruence but only three of them were statistically significant and were hence removed from the subsequent analyses based on the combined data set. Our data do not support Diestrammena as monophyletic while representatives of ParadiestrammenaEutachycines and Paratachycineswere clustered together; the validity of some nominal species was confirmed molecularly but we also revealed a large number of deeply divergent lineages. Populations with the same degree of troglomorphosis do not cluster together. We identified five major clades; divergence among them (and in a few circumstances also within them) is always higher than the DNA barcode threshold for intraspecific comparisons in insects. In two circumstances, the same clades (III and V) are co-distributed in geographically distinct areas (Provinces). This geographical distribution might be explained by envisioning an evolutionary scenario based on zones of secondary admixture following epigean dispersal among lineages that diverged in allopatry.


AN EVALUATION OF AUTOMATED GIS TOOLS FOR DELINEATING KARST SINKHOLES AND CLOSED DEPRESSIONS FROM 1-METER LIDAR-DERIVED DIGITAL ELEVATION DATA, 2013, Doctor D. H. , Young J. A.

LiDAR (Light Detection and Ranging) surveys of karst terrains provide high-resolution digital elevation models (DEMs) that are particularly useful for mapping sinkholes. In this study, we used automated processing tools within ArcGIS (v. 10.0) operating on a 1.0 m resolution LiDAR DEM in order to delineate sinkholes and closed depressions in the Boyce 7.5 minute quadrangle located in the northern Shenandoah Valley of Virginia. The results derived from the use of the automated tools were then compared with depressions manually delineated by a geologist. Manual delineation of closed depressions was conducted using a combination of 1.0 m DEM hillshade, slopeshade, aerial imagery, and Topographic Position Index (TPI) rasters. The most effective means of visualizing depressions in the GIS was using an overlay of the partially transparent TPI raster atop the slopeshade raster at 1.0 m resolution. Manually identified depressions were subsequently checked using aerial imagery to screen for false positives, and targeted ground-truthing was undertaken in the field. The automated tools that were utilized include the routines in ArcHydro Tools (v. 2.0) for prescreening, evaluating, and selecting sinks and depressions as well as thresholding, grouping, and assessing depressions from the TPI raster. Results showed that the automated delineation of sinks and depressions within the ArcHydro tools was highly dependent upon pre-conditioning of the DEM to produce “hydrologically correct” surface flow routes. Using stream vectors obtained from the National Hydrologic Dataset alone to condition the flow routing was not sufficient to produce a suitable drainage network, and numerous artificial depressions were generated where roads, railways, or other manmade structures acted as flow barriers in the elevation model. Additional conditioning of the DEM with drainage paths across these barriers was required prior to automated 2delineation of sinks and depressions. In regions where the DEM had been properly conditioned, the tools for automated delineation performed reasonably well as compared to the manually delineated depressions, but generally overestimated the number of depressions thus necessitating manual filtering of the final results. Results from the TPI thresholding analysis were not dependent on DEM pre-conditioning, but the ability to extract meaningful depressions depended on careful assessment of analysis scale and TPI thresholding.


An approach for collection of nearfield groundwater samples in submerged limestone caverns, 2013, Mills Aaron L. , Tysall Terrence N. , Herman Janet S.

Walls of submerged caves feeding Florida springs are often lined with a heavy mat of filamentous bacteria, many of which are able to oxidize reduced sulfur in groundwater migrating from the porous bedrock into the cave conduit. To determine changes in water chemistry as water passes through the microbial mat, a simple device made from standard well screen and sealed with a rubber stopper and controllable vents was installed in a hole drilled in the wall of the cave passage. The sampler was sealed in place with marine epoxy. we measured anions in water from the sampler and from the water-filled conduit taken just outside the sampler. Most anions measured viz., Cl, NO3, and PO43−, increased slightly between the matrix and conduit waters. However, traces of sulfide were measured in the water from the rock matrix, but not in the conduit. SO4 2−concentrations in the conduit were about twice that measured in the water from the sampler, about 22 and 11 mg SO42− L−1, respectively, providing further evidence that sulfur oxidation is an important process in the bacterial mats attached to the limestone surfaces in these caves. An additional use of the sampling device is to measure discharge from the local bedrock into the cave conduit.


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