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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That transmissibility coefficient is the use of the term transmissibility has been replaced by transmissivity [22]. see transmissivity.?

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;
See all featured articles from other geoscience journals

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Your search for gpr (Keyword) returned 24 results for the whole karstbase:
Showing 16 to 24 of 24
GPR detection of karst and archaeological targets below the historical centre of Merida, Yucatn, Mexico, 2009,
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Barba Luis, Blancas Jorge, Ortiz Agustin, Ligorred Josep

The Historical Center of Merida has been classified as a “zone of high patrimonial value” based on the study of topography and the historical documents that show a long-term occupation, non-interrupted since pre- Columbian times when T’Hó was the great capital of the northern region of the Maya area. For the local government, rehabilitation of the Historical Center of Merida has been a great priority. Among others, this project includes preservation of archaeological remains (pre-Columbian or colonial) and detection of karstic zones under the city. In order to prevent damage to the patrimony, ground penetrating radar (GPR) surveys were carried out employing 200 and 400 MHz antennas along 16.5 km of the city streets. After data analysis, it was possible to build a map showing the locations of subsurface karst features and archaeological remains below the street pavement, many of which correlate with archaeological platforms proposed in historic documents as well as some of the cenotes recorded in popular memory. As result, for the first time in Mexico, a local government has information available that will allow them to minimize damage to archaeological remains and mitigate risks associated with construction above shallow subsurface karstic zones within this important modern city

Investigating Ancient Maya Agricultural Adaptation through Ground Penetrating Radar (GPR) Analysis of Karst Terrain , Northern Yucat n, Mexico, 2010,
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Munro Stasiuk Mandy J. & Manahan T. Kam
Landscape adaptation on the Northern Yucatn Peninsula, Mexico, is particularly difficult, as soils are thin and the terrain is devoid of any surface water other than the occasional sinkhole (cenote) that connects directly to the groundwater system. Despite this, ancient Maya cities, including Xuenkal, emerged and thrived, likely because of their proximity to natural sinkholes. In the case of Xuenkal, these sinkholes, known locally as rejolladas, have bases above the local water table and, as such, do not provide direct access to the underlying water, but they provide closer access. Recognizing that the presence of rejolladas was likely important to the ancient Maya the purpose of this study is to characterize the rejolladas in terms of their subsurface characteristics, specifically bedrock configuration and soil. Ground penetrating radar analysis, as well as the results of a test pit excavation, confirm the presence of deep soils in the rejollada bases. It seems that the smaller deeper rejolladas have the thickest soils and sediment. The ancient city of Xuenkal is constructed amidst a particularly dense cluster of rejolladas which may have contributed to its location. Rejolladas, containing significantly thicker soils than the surrounding karst surface, and the ability to sustain dense healthy vegetation would have been particularly desirable for the Maya to capitalize on.

Contributions of geophysical techniques to the exploration of the Molnár János Cave (Budapest, Hungary), 2010,
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Surá, Nyi Gergely, Dombrá, Di Endre, Leé, LŐ, Ssy Szabolcs

Located in the centre of the Pannonian, one of the hottest basins in Europe with high average heat flow values, Hungary has long been famous for hot water springs and frequent cave occurrences. The Molnár János Cave, an active thermokarstic cave, belonging to the Buda Hills karst system, lies beneath a highly populated district of Budapest. Its large passages are almost completely filled by lukewarm water. Only the upper part of its largest known chamber rises above the water level, which offers an excellent site to examine recent cave generation processes. However, hitherto, no dry subsurface gateway existed towards this chamber; it was only accessible underwater. In this paper, we present the results of various geophysical investigations including GPR, magnetic and seismic methods, carried out in a close cooperation between geophysicists and speleologists. The aim of the measurements was to determine the precise position of the hall relative to a nearby drift. Based upon the successful seismic survey and first break analysis, a precise and efficient boring could be designed to realise the connection. Finally, a passage between the two cavities has been established and, thus, the chamber of the cave is now accessible to the whole scientific community.

GPR detection of several common subsurface voids inside dikes and dams, 2010,
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Xu X. , Zeng Q. , Li D. , Wu J. , Wu X. , Shen J.

Ground-penetrating radar (GPR) technique has been used in detecting several common subsurface voids inside dikes and dams in south of China, and the results indicate that GPR can be successfully applied to uncovering termite nests inside dikes and dams, and the technique proves to be advantageous in real-time retrieval of detection data, precise positioning and effect of application being basically not affected by locality and climate, when it is compared to other available methods. GPR is also effective in detecting cracks in the sloping clay core, and proves to pose less impact on the normal operation of the detected hydraulic projects, be more efficient, and capable of retrieving more comprehensive detection data, when compared with the method of artificial observation through holes chiseled out from the ground. Also, GPR is capable of detecting ferralsol in tropical and subtropical regions to some depth, and shows high value of application in detecting some hidden troubles such as caves and settlements with low to moderate depths inside dams in karst regions. Moreover, GPR technique proves to be so capable of detecting carbonate rocks to certain depth and can yield precise results that it can be applied to analysis and discovery of leakage channels inside reservoirs in karst regions

A comparative integrated geophysical study of Horseshoe Chimney Cave, Colorado Bend State Park, Texas, 2011,
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Brown W. A. , Stafford K. , Shawfaulkner M. , Grubbs A.

An integrated geophysical study was performed over a known cave in Colorado Bend State Park (CBSP), Texas, where shallow karst features are common within the Ellenberger Limestone. Geophysical survey such as microgravity, ground penetrating radar (GPR), direct current (DC) resistivity, capacitively coupled (CC) resistivity, induced polarization (IP) and ground conductivity (GC) measurements were performed in an effort to distinguish which geophysical method worked most effectively and efficiently in detecting the presence of subsurface voids, caves and collapsed features. Horseshoe Chimney Cave (HCC), which is part of a larger network of cave systems, provides a good control environment for this research. A 50 x 50 meter grid, with 5 m spaced traverses was positioned around the entrance to HCC. Geophysical techniques listed above were used to collect geophysical data which were processed with the aid of commercial software packages. A traditional cave survey was conducted after geophysical data collection, to avoid any bias in initial data collection. The survey of the cave also provided ground truthing. Results indicate the microgravity followed by CC resistivity techniques worked most efficiently and were most cost effective, while the other methods showed varying levels of effectiveness.

The Dead Sea sinkhole hazard: Geophysical assessment of salt dissolution and collapse, 2011,
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Frumkin Amos, Ezersky Michael, Alzoubi Abdallah, Akkawi Emad, Abueladas Abdelrahman

A geophysical approach is presented for analyzing processes of subsurface salt dissolution and associated sinkhole hazard along the Dead Sea. The implemented methods include Seismic Refraction (SRFR), Transient Electromagnetic Method (TEM), Electric Resistivity Tomography (ERT), and Ground Penetration Radar (GPR). The combination of these methods allows the delineation of the salt layer boundaries, estimating its porosity distribution, finding cavities within the salt layer, and identifying deformations in the overlying sediments. This approach is shown to be useful for anticipating the occurrence of specific sinkholes, as demonstrated on both shores of the Dead Sea. These sinkholes are observed mainly along the edge of a salt layer deposited during the latest Pleistocene, when Lake Lisan receded to later become the Dead Sea. This salt layer is dissolved by aggressive water flowing from adjacent and underlying aquifers which drain to the Dead Sea. Sinkhole formation is accelerating today due to the rapid fall of the Dead Sea levels during the last 30 years, caused by anthropogenic use of its water.

Integrating geomorphological mapping, trenching, InSAR and GPR for the identification and characterization of sinkholes: A review and application in the mantled evaporite karst of the Ebro Valley (NE Spain), 2011,
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Gutié, Rrez Francisco, Galve Jorge Pedro, Lucha Pedro, Castañ, Eda Carmen, Bonachea Jaime, Guerrero Jesú, S

This contribution illustrates the advantages of integrating conventional geomorphological methods with InSAR, ground penetrating radar and trenching for sinkhole mapping and characterization in a mantled evaporite karst area, where a significant proportion of the karstic depressions have been obliterated by artificial fills. The main practical aim of the investigation was to elucidate whether buried sinkholes overlap the areas planned for the construction of buildings and services, in order to apply a preventive planning strategy. Old aerial photographs and detailed topographic maps were the most useful sources of information for the identification of sinkholes and helped to obtain information on their chronology, either a minimum age or bracketing dates. The InSAR technique provided subsidence rate values ranging from 4.4 to 17.3 mm/yr consistent with the spatial distribution of the mapped sinkholes. This quantitative deformation data helped corroborating independently the existence of active buried sinkholes and improving the delineation of their limits. The GPR profiles contributed to the precise location of sinkhole edges, provided information on the geometry of buried sinkholes and deformation structures and helped to site trenches and to rule out the existence of sinkholes in particular areas. The main input derived from the trenches includes: (1) Confirming or ruling out anomalies of the GPR profiles attributable to subsidence. (2) Precise location of the edge of some filled sinkholes. (3) Information on subsidence mechanisms recorded by various deformation structures and cumulative subsidence magnitude. (4) Calculating minimum long-term subsidence rates using radiocarbon dates obtained from deformed sinkhole deposits. (5) Unequivocal evidence of active subsidence in areas assigned for the construction of buildings

Paleokarst Breccia-Pipe Reservoir Analogue, Carboniferous, Svalbard, 2011,
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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.

Analysis of the capabilities of low frequency ground penetrating radar for cavities detection in rough terrain conditions: The case of Divača cave, Slovenia , 2012,
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Gosar, Andrej

High frequency ground penetrating radar (GPR) is usually applied for cavities detection in a shallow subsurface of karst areas to prevent geotechnical hazards. For specific projects, such as tunnel construction, it is important to detect also larger voids at medium depth range. However, dimensions of classical rigid low frequency antennas seriously limit their applicability in a rough terrain with dense vegetation commonly encountered in a karst. In this study recently developed 50 MHz antennas designed in a tube form were tested to detect cave gallery at the depth between 12 m and 60 m. The Divaca cave was selected because of a wide range of depths under the surface, possibility of unknown galleries in the vicinity and a rough terrain surface typical for Slovenian karst. Seven GPR profiles were measured across the main gallery of the cave and additional four profiles NE of the cave entrance where no galleries are known. Different acquisition and processing parameters were analysed together with the data resolution issues. The main gallery of the cave was clearly imaged in the part where the roof of the gallery is located at the depth from 10 m to 30 m. The width of the open space is mainly around 10 m. Applied system was not able to detect the gallery in the part where it is located deeper than 40 m, but several shallower cavities were discovered which were unknown before. The most important result is that the profiles acquired NE of the cave entrance revealed very clearly the existence of an unknown gallery which is located at the depth between 15 m and 22 m and represents the continuation of the Divaca cave. Access to this gallery is blocked by the sediment fill in the entrance shaft of the cave. The results of the study are important also for future infrastructure projects which will involve construction of tunnels through karstified limestone and for speleological investigations to direct the research efforts.

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