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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 redox potential (Eh) is oxidation-reduction potential [16].?

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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.
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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 geophysic (Keyword) returned 162 results for the whole karstbase:
Showing 16 to 30 of 162
The Silica nappe (s.l.) of the Inner West Carpathians consists of an essentially non-metamorphic, platform-type sedimentary complex of Mesozoic (chiefly Triassic) age. Palaeomagnetic samples were collected from 16 sites throughout the southern and northern Gemeric parts of this unit and from one site of the Mesozoic Meliata series which underlies the Silica nappe (s.s.) in south Gemer. The samples from each site were treated using thermal demagnetization and well-grouped magnetic directions of individual components were found for 13 (14) sites. Detailed analysis of the directional data showed (a) post-folding magnetization for four late Triassic-Jurassic sites in the eastern Slovak Karst, (b) synfolding magnetization for five sites in the western Slovak Karst with a direction corresponding to local palaeomagnetic data of African affinity for the late Cretaceous and (c) primary magnetizations in the northern Gemeric area for only two rock units with a declination difference which implies a relative rotation between these units. As all secondary remanences are of normal polarity it is very likely that their acquisition is related to the emplacement of the Silica nappe during the early late Cretaceous. The dominant remagnetization mechanism probably is CRM but occasional contributions of TVRM are also conceivable

Upper Ordovician Arthur Marble and Oligocene Takaka Limestone contain extensive phreatic cave systems beneath the Takaka valley and Golden Bay. Half of all water flows in the Takaka valley pass through subterranean drainage conduits in carbonate rock. New Zealand's largest freshwater springs, the Waikoropupu Springs, are one surface expression of these karst systems. Other characteristics are dolines and submarine springs. A paleocave system developed in the Arthur Marble during the formation of the northwest Nelson peneplain in the Late Cretaceous and early Tertiary. Subsequent subsidence of the peneplain, and deposition of Motupipi Coal Measures, Takaka Limestone, and Tarakohe Mudstone, was followed by folding and faulting of the sequence in the Kaikoura Orogeny. Uplift and erosion in the Pleistocene brought the two carbonate rock formations within reach of groundwater movements. The paleocave system in Arthur Marble was reactivated during periods of glacial, low sea levels, and a smaller cave system formed in the overlying Takaka Limestone. Both systems interact and extend to more than 100 m below present sea level, forming the Arthur Marble - Takaka Limestone aquifer

A propos de gophysique et de la dtection de cavits profondes inconnues, 1992, Choppy, J.
About unknown deep cave detection by geophysic

Kotumsar Cave Ecosystem: An Interaction Between Geophysical, Chemical, and Biological Characteristics, 1992, Biswas, J.

Rospo Mare (Adriatique), un palokarst ptrolier du domaine mditerranen, 1993, Dubois P. , Sorriaux P. , Soudet H. J.
The oil paleokarst of Rospo Mare (Adriatic Sea) The oil field of Rospo Mare is located in the Adriatic Sea, 20 km of the Italian coast. The reservoir lies at the depth of 1300m and consists of a paleokarst of Oligocene to Miocene age, which developed within Cretaceous limestones, now covered with 1200m of mio-pliocene sequences. The oil column is about 140m high. The karstic nature of the reservoir was identified through vertical, cored drill holes which allowed the analysis of the various solutional features and the sedimentary infilling (speleothems, terra rossa, marine clays), as well as their vertical distribution. Erosion morphology at the top of the karst is highly irregular, including paleovalleys as well as many pit-shaped sinkholes. Observations concerning the upper part of the reservoir were compared to a paleokarst of the same age, outcropping widely onshore, in nearby quarries. Detailed knowledge of that morphology through geophysics helped to optimise the development of the field through horizontal drilling. The paleokarst of Rospo Mare is an integral part of the pre-miocene paleokarst assemblages of the periphery of the Mediterranean, which were formed in tropical conditions.

Hydrogeology of the reservoirs planned in Lower Zamanti Basin and karst related problems, 1993, Bayari C. Serdar, Gureri Brahim
This study aims to define the karst related problems that may arise during the implementation of three weir and two dam projects planned in the Lower Zamanti Basin. Based on the regional hydrogeological investi-gations, the problems that may arise during the construction phase were outlined and relevant investigation techniques were proposed. This study showed that no water leakage problem is expected in the reservoir areas of Çamlıca II , Çamlıca III, Tatlar weirs and Göktaş dam, while the possibility of leakage thorugh the reservoir of the Topraktaş dam should be investigated by means of geophysical surveys and exploratory boreholes. The same suggestions are also valid for the energy tunnels of Çamlıca II, Tatlar weirs and Göktaş dam where dewatering of karst groundwater would be an important problem.

lsotopic patterns in modern global precipitation, 1993, Rozanski K. , Araguasaraguas L. , Gonfiantini R.

The Rospo Mare oil field is located in the Adriatic Sea, 20 km off the Italian coast. The reservoir lies at a depth of 1300 m and consists of a paleokarst oi Oligocene to Miocene age which developed within Cretaceous limestones, now covered by 1200 m of Mio-Pliocene sequences. The oil column is about 140 m 8 high. The karstic nature of the reservoir was identified through vertical, cored drill holes which allowed us to analyse the various solution features and the sedimentary infilling (speleothems, terra rossa, marine clays), as well as their vertical distribution. Erosion morphology at the top of the karst is highly irregular, including in particular paleovalleys as well as many pit-shaped sink holes. Detailed geophysical knowledge of that morphology helped to optimize the development of the field through horizontal drilling. Observations concerning the upper part of the reservoir were compared to a palaeokarst of the same age, outcropping widely onshore, in quarries located nearby. The Rospo Mare paleokarst is an integral part of the ante Miocene paleokarst assemblages of the periphery of the Mediterranean which were formed in tropical conditions. Only the fractures enhanced by meteoric water during the formation of the karat are important for reservoir connectivity. During the formation of the karst there were several phases of dissolution and infilling which modified the geometry of the open fissures and only these fractures play an important role in the reservoir drainage. Vertically we can distinguish three very different zones from top to bottom: at the top the epikarst (0-35 m) in a zone of extension. All the fractures have been enlarged by dissolution but the amount of infilling by clay is substantial. The clays are derived either from alteration of the karat fabric or by deposition during the Miocene transgression; the percolation zone (15-45 m) is characterized by its network of large fractures vertically enlarged by dissolution which corresponds to the relict absorption zones in the paleokarst. These fractures, which usually have a pluridecametric spacing, connect the epi-karst with the former sub-horizontal river system. This zone has been intersected by the horizontal wells during the field development. In this zone there are local, horizontal barriers oi impermeable clay which can block vertical transmissibility. In these low permeability zones the vertical fractures have not been enlarged due to dissolution hence the horizontal barrier; the zone of underground rivers (35-70 m) is characterized by numerous horizontal galleries which housed the subterranean ground water circulation. When these fissures are plurimetric in extent this can lead to gallery collapse with the associated fill by rock fall breccia. This can partly block the river system but always leaves a higher zone of free circulation with high permeabilities of several hundreds of Darcys. These galleries form along the natural fracture system relative to the paleohydraulic gradient which in some cases has been preserved. The zone below permanent ground water level with no circulation of fluids is characterized by dissolution limited to non-connected vugs. Very locally these fissures can be enlarged by tectonic fractures which are non-connected and unimportant for reservoir drainage. Laterally, only the uppermost zone can be resolved by seismic imaging linked with horizontal well data (the wells are located at the top of the percolation zone). The Rospo Mare reservoir shows three distinct horizontal zones: a relict paleokarst plateau with a high index of open connected fractures, (area around the A and B platforms); a zone bordering the plateau (to the north-east of the plateau zone) very karstified but intensely infilled by cap rock shales (Miocene - Oligocene age); a zone of intensely disturbed and irregular karst paleotopography which has been totally infilled by shales. The performance of the production wells is dependent on their position with respect to the three zones noted above and their distance from local irregularities in the karst paleotopography (dolines, paleovalleys)

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

ELECTROMAGNETIC AND SEISMOACOUSTIC SIGNALS REVEALED IN KARST CAVES (CENTRAL ITALY), 1995, Bella F, Biagi Pf, Caputo M, Dellamonica G, Ermini A, Plastino W, Sgrigna V, Zilpimiani D,
Since 1988-89 equipment for detecting electric, magnetic and seismoacoustic signals has been running inside the Amare cave. The Amare cave is placed on the southern slope of the Gran Sasso chain, that is one of the largest karst areas of the Italian Apennines. In 1992, a similar equipment was installed inside the Cervo cave. This cave is located in another karst area of the Central Apennines, at about 50 km southwestwards of the Amare cave. In both these measurements sites, the signals are recorded every ten minutes in a digital form; the equipment is able to record signals, the frequency of which ranges from some hundred Hz to some hundred kHz. The data collected up to now seem to identify two different states that we call ''quiet'' and ''perturbed'' state. In the quiet state only electric and magnetic signals with the highest frequencies appear. These signals are connected with radio broadcastings and with the general lightnings activity of the Earth. A perturbed state is characterized by the sudden appearance of seismoacoustic signals coupled with electric and magnetic ones. This phenomenology is connected with local processes. Rainfall, atmospheric-pressure variations and some thermal effects are responsible for these local processes. A possible model is proposed to justify the observed phenomenology: micromovements of the limestone blocks that constitute the roof of the caves are invoked for the production of seismoacoustic signals. The electrification generated by these movements is invoked for the production of electric and magnetic signals

Geological and hydrogeological remote sensing techniques can be applied very favorably to Dinaric karst in the Balkans, a well-known reference area for studies of karst phenomena. The elements that make karst terrain of the Dinarides suitable for remote sensing are geomorphologic characteristics, in particular the specific surface drainage and karst forms, the varying vegetation that most often reflects the existence of different geologic formations on the surface, and distinct tectonic features. Some of the world's largest springs, ponors (sinks), and dolines are controlled by fractures visible on both satellite images and aerial photographs. Lineaments represent fault zones, systems of close faults with similar strike, or large individual faults which all are young or show recently renewed activity. Their neotectonic character and major importance for karst groundwater flow are confirmed by numerous field investigations including water tracing, geophysical research, and drilling

Mapping karst solution features by the integrated geophysical method, 1995, Rodriguez R.

Yucatan karst features and the size of Chicxulub crater, 1996, Connors M, Hildebrand Ar, Pilkington M, Ortizaleman C, Chavez Re, Urrutiafucugauchi J, Granielcastro E, Camarazi A, Vasquez J, Halpenny Jf,
The buried Chicxulub impact structure is marked by a dramatic ring of sinkholes (called cenotes if containing water), and adjacent less prominent partial rings, which have been shown to coincide with maxima in horizontal gravity gradients and a topographic depression. These observations; along with the discreteness and spacing of the features, suggest a formation mechanism involving faulting in the outer slump zone of the crater, which would thus have a diameter of approximately 180 km, An opposing view, based primarily on the interpretation of gravity data, is that the crater is much larger than the cenote ring implies, Given the association of the known cenote ring with faults, we here examine northern Yucatan for similar rings in gravity, surface features and elevation, which we might expect to be associated with outer concentric faults in the case of a larger, possibly multiring, structure, No such outer rings have been found, although definite patterns are seen in the distribution of karst features outside the crater rim, We explain these patterns as resulting mainly from deformation related to the block fault zone that parallels the shelf edge of eastern Yucatan

3-D seismic evidence of the effects of carbonate karst collapse on overlying clastic stratigraphy and reservoir compartmentalization, 1996, Hardage B. A. , Carr D. L. , Lancaster D. E. , Simmons J. L. , Elphick R. Y. , Pendleton V. M. , Johns R. A. ,
A multidisciplinary team, composed of stratigraphers, petrophysicists, reservoir engineers, and geophysicists, studied a portion of Boonsville gas field in the Fort Worth Basin of north-central Texas to determine how modern geophysical, geological, and engineering techniques can be combined to understand the mechanisms by which fluvio-deltaic depositional processes create reservoir compartmentalization in a low- to moderate-accommodation basin. An extensive database involving well logs: cores, production, and pressure data from more than 200 wells, 26 mi(2) (67 km(2)) of 3-D seismic data, vertical seismic profiles (VSPs), and checkshots was assembled to support this investigation. We found the mast Important geologic influence on stratigraphy and reservoir compartmentalization in this basin to be the existence of numerous karst collapse chimneys over the 26-mi(2) (67 km(2)) area covered by the 3-D seismic grid, These near-vertical karst collapses originated in, or near, the deep Ordovician-age Ellenburger carbonate section and created vertical chimneys extending as high as 2500 fl (610 m) above their point of origin causing significant disruptions in the overlying elastic strata. These karst disruptions lend to be circular in map view, having diameters ranging from approximately 500 ft (150 m) to as much as 3000 ft (915 m) in some cases. Within our study area, these karat features were spaced 2000 ft (610 m) to 6000 ft (1830 m) apart, on average. The tallest karst collapse zones reached into the Middle Pennsylvanian Strawn section, which is some 2500 ft (760 m) above the Ellenburger carbonate where the karst generation began. We used 3-D seismic imaging to show how these karst features affected the strata above the Ellenburger and how they have created a well-documented reservoir compartment in the Upper Caddo, an upper Atoka valley-fill sandstone that typically occurs 2000 ft (610 m) above the Ellenburger. By correlating these 3-D seismic images with outcrops of Ellenburger karat collapses, we document that the physical dimensions (height, diameter, cross-sectional area) of the seismic disruptions observed in the 3-D data equate to the karst dimensions seen in outcrops. We also document that this Ellenburger carbonate dissolution phenomenon extends over at least 500 mi (800 km), and by inference we suggest karst models like we describe here may occur in any basin that has a deep, relatively thick section of Paleozoic carbonates that underlie major unconformities

Side-looking sonar backscatter response at dual frequencies, 1996, Ryan William B. F. , Flood Roger D. ,

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