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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 bend is curve in a water course [16].?

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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 polarization (Keyword) returned 6 results for the whole karstbase:
A comparative integrated geophysical study of Horseshoe Chimney Cave, Colorado Bend State Park, Texas, , Brown Wesley A. , Stafford Kevin W. , Shawfaulkner Mindy , Grubbs Andy

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.


SHALLOW KARST EXPLORATION USING MT-VLF AND DC RESISTIVITY METHODS, 1995, Guerin R. , Benderitter Y. ,
A geophysical test was carried out over a well-located and fairly embedded karstic conduit. The MT-VLF method was selected because of its high resolution and its ability to provide a resistivity parameter sensitive to water and clay. This method was used together with DC resistivity methods which allow vertical adjustment of the VLF data and show consistency between the investigation and target depths. After correcting the deformations due to the polarization of the primary field, the MT-VLF data show clearly, in the central part of the site, that the conduit does not coincide with an anomaly axis but coincides with the boundary between a conductive area and a resistive area. 2D modelling confirms that direct detection of the conduit is not feasible and that the conduit is located close to a conductive zone corresponding to a completely clay-filled fractured zone. This situation was observed on the whole site and the conduit seemed systematically to thread its way between the conductive zones to join the outlet. The distribution of the conductive fractured zones and the direction of the hydraulic gradient were two important elements in predicting the location of the conduits. A 3D approach would increase the probability of finding the conduits in such a case

Palaeomagnetic Research of a Fossil Cave in the Highway Construction at Kozina, SW Slovenia, 2000, Bosá, K Pavel, Knez Martin, Otrubová, Dana, Pruner Petr, Slabe Tadej, Venhodová, Daniela

A fossil channel was filled by sandy sediments of light brown to ochreous color with dynamic structures and textures (lower sequence) unconformably overlain by remains of collapsed roof with brown and ochreous matrix (upper sequence). The sedimentary profile was about 5 m high. In all 38 samples taken from the profile, only one was cemented. Samples were demagnetised by alternating field (AF) at 10 to 1,000 Oe. The cemented one was demagnetised by gradual thermal process from 80 to 560 °C in the MAVACS apparatus. Detected remanent magnetisation in a natural state varied between 95 and 36,470 pT, values of volume magnetic susceptibility are from 55 to 998 x 10-6 SI. Rocks showed low or medium magnetisation. Normal and inverse polarization was detected after demagnetisation. The primary component of magnetisation and resulting polarity could not be stated in samples with expressive viscose component (up to 90 %). According to arrangement of individual magnetozone, it can be stated that sediments are older than the top of Olduvai chron (1.77 Ma), as the magnetostratigraphic profile at Kozina terminated by reverse polarised magnetozone and contains two normal polarised zones. The profile can be correlated with the Divača profile, not only from the palaeomagnetic point of view, but also from a lithological point of view. We suppose, as in Divača, that the cave is a result of the Messinian speleogenetic epoch and its fossilization was connected with rapid base level uplift after refilling of the Mediterranean basin by water. If this hypothesis is close to reality, the fossilization process can be dated from about 5.2 Ma up.


Observation of bicarbonate in calcite by NMR spectroscopy, 2006, Feng J, Lee Yj, Reeder Rj, Phillips Bl,
We show that the signal observed in 13C{1H} cross-polarization magic-angle-spinning (CP/MAS) NMR spectra of synthetic calcite precipitated at room temperature arises from bicarbonate ion. Although this peak occurs at the same chemical shift as for the bulk carbonate signal, its observation by CP/MAS indicates that it corresponds to carbonate associated with H. The variation in the CP/MAS intensity with contact time shows oscillations characteristic of C-H pairs separated by 1.9(1) A and remote from other H, consistent with bicarbonate. 13C{1H} heteronuclear correlation spectra indicate that the hydrogen in the bicarbonate groups gives a relatively narrow 1H NMR signal at .4 ppm. A peak at this chemical shift is also observed in direct-observe 1H MAS NMR spectra of the synthetic sample, and also in natural biogenic and abiogenic calcite. This 1H chemical shift indicates a moderate hydrogen bonding interaction d(OH...O) {approx}1.85 A, which suggests significant structural relaxation occurs near the bicarbonate

CAVE SEDIMENTS FROM THE POSTOJNSKAPLANINSKA CAVE SYSTEM (SLOVENIA): EVIDENCE OF MULTI-PHASE EVOLUTION IN EPIPHREATIC ZONE, 2008, Zupan Hajna N. , Pruner P. , Mihevc A. , Schnabl P. , BosÁ, K P.

The Postojnska jama–Planinska jama cave system and number of smaller adjacent caves are developed in the Postojnski kras. These caves are located between two dextral strike-slip fault zones oriented in the Dinaric direction. The caves contain lithologically diversified cave fill, ranging from speleothems to allogenic fluvial sediments. The allogenic clastic material is derived from a single source, Eocene siliciclastics of the Pivka Basin. Small differences in mineral/petrologic composition between the sediments can be attributed to different degrees of weathering in the catchment area and homogenization of source sediments. Thick sequences of fine-grained laminated sediments, deposited from suspension are common. The depositional environment was mostly calm, but not completely stagnant. Such a sedimentary environment can be described as cave lacustrine, with deposition from pulsed flow. The homogeneity of the palaeomagnetic data suggests rapid deposition by a number of short-lived single-flood events over a few thousand years. This depositional style was favourable for recording of short-lived excursions in the palaeomagnetic field. The sediments were originally not expected to be older than Middle Quaternary in age (i.e. about 0.4 Ma). Later numerical dating (Th/U and ESR) indicated ages older than 0.53 ka. New palaeomagnetic data from selected sedimentary profiles within the cave system detected normal polarization in much of the profiles studied. Reverse polarized magnetozones, interpreted mostly as short- lived excursions of magnetic field, were detected in only a few places. Therefore, we interpreted most of the sediments as being younger than 0.78 Ma, belonging to different depositional phases within the Brunhes chron. Palaeomagnetic properties of two profiles in caves intersected by the artificial tunnel between Postojnska jama and Črna jama had reverse polarized magnetozones and of sediments in Zguba jama, may indicate an age much greater than 0.78 Ma. The cave system has evolved over a long period of time, governed by the functioning of Planinsko polje in the relation to the evolution of the resurgence area in Ljubljana Moor further to the east. General stabilization of the hydrological system with low hydraulic head led to the evolution of caves in epiphreatic and paragenetic conditions over a long time-span. Individual cave segments or passages were completely filled and exhumed several times during the evolution of the cave. Alternation of depositional and erosional phases may be connected with changing conditions within the cave system, the functioning of the resurgence area, collapse, climatic change, tectonic movement and the intrinsic mechanisms of contact karst.


A comparative integrated geophysical study of Horseshoe Chimney Cave, Colorado Bend State Park, Texas, 2011, 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.


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