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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. ...

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That interbedded is pertaining to beds or sedimentary material intercalated in a parallel fashion into a main stratum [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 gravity (Keyword) returned 75 results for the whole karstbase:
Showing 31 to 45 of 75
Speleothem rupture in karst: tectonic or climatic origin? U-Th dating of rupture events in Salamandre Cave (Gard, southeastern France), 2004, Ponsbranch, Hamelin B. , Brulhet J. , Bruxelles L. ,
Caves are relatively protected from the main external erosional factors. Therefore, they constitute potentially reliable places for long-term conservation of continental history. Moreover their secondary carbonated deposits, the speleothems, can be dated precisely on the 0-500 ka time-scale using U-series isotopes measured by thermo-ionisation mass spectrometry (TIMS). Tectonic events (tectonic displacements and earthquakes) may change cave morphology and induce speleothem breaking or displacement as has been shown by previous studies performed mainly in Italy [Forti et Postpischl, 1984; Postpischl et al., 1991 for example]. Nevertheless, collapses of speleothems observed today in caves are difficult to interpret as their origin may be linked to several other natural processes. We studied the Aven de la Salamandre cave located in southeastern France (Gard), an area between the Cevennes fault and the Nimes fault, where evidence of Quaternary vertical movements was previously described. However, this region is not considered to be a seismic active zone. The Aven de la Salamandre cave is characterized by numerous broken speleothems. Some of them are very large and a lot of them are covered by growth of new calcite or new speleothem generation. We report here 13 TIMS U/Th analysis performed on two broken speleothems recovered by second generation calcite growth. Dating results are discussed through time corrections due to detrital content of calcite. In the first sequence, a 7 0.35 ka fracture event is identified. In the second sequence, the age of the breakdown is between 1.1 0.1 and 6.3 2 ka. These events could thus be contemporary. Hypotheses for the origin of this fracture event are presented and discussed: (i) karstic catastrophic event due to intense climatic changes or to cavity collapse (break down of hanging wall, gravity, landslide...); (ii) co-seismic ruptures. The first conclusion of this study is that these collapse episodes in the Aven de la Salamandre cave cannot be due to the direct effect of an earthquake or climatic event. Only indirect effects of flooding (by mobilization of the argillaceous components of the floor and consecutive destabilization of the speleothems growing upon it) or earthquake effects (more likely by local effects than by wave front passage) are privileged. By comparing our dating with regional destructive known events (in other karsts, in cliffs and scarps), dated by relative chronology, we are lead to propose a regional generalized event precisely dated here at 7 ka. This second conclusion doesn't contradict the presence of unbroken speleothems older than 100 ka found in other caves in the neighborhood as local effects is one of the predominant factors relative to speleothem stability. As a final conclusion, this paper promotes the use of speleothems as reliable datable tools for assessing regional stability problems (sensitivity to seismic hazards, to destructive intense climatic events...) as is done for paleoclimatic reconstruction

Origin of the salt valleys in the Canyonlands section of the Colorado Plateau - Evaporite-dissolution collapse versus tectonic subsidence, 2004, Gutierrez F. ,
The salt valleys over the axis of the salt-cored anticlines in the Paradox fold and fault belt (Canyonlands, Utah and Colorado) are created by subsidence of the anticline crests. Traditionally, the collapse of the anticlinal crests was attributed to dissolution of the salt walls (diapirs) forming the anticline cores. Recent studies based on scaled physical models and field observations propose that the salt valleys are a result of regional extension and that salt dissolution had only a minor influence in the development of the axial depressions. This paper presents several arguments and lines of evidence that refute the tectonic model and support the salt dissolution subsidence interpretation. The development of contractional structures in salt dissolution experiments led the advocates of the tectonic interpretation to reject the dissolution-induced subsidence explanation. However, these salt dissolution models do not reproduce the karstification of salt walls in a realistic way, since their analog involves removal of salt from the base of the diapirs during the experiments. Additionally, numerous field examples and laboratory models conducted by other authors indicate that brittle subsidence in karst settings is commonly controlled by subvertical gravity faults. Field evidence against the regional extension model includes (1) a thick cap rock at the top of the salt walls, (2) the concentration of subsidence deformation structures along the crest of the anticlines (salt walls), (3) deformational structures not consistent with the proposed NNE extension, like crestal synforms and NE-SW grabens, (4) dissolution-induced subsidence structures controlled by ring faulting, revealing deep-seated dissolution, (5) large blocks foundered several hundred meters into the salt wall, (6) evidence of recent and active dissolution subsidence, and (7) the aseismic nature of the recently active collapse faults. Although underground salt dissolution seems to be the main cause for the generation of the salt valleys, this phenomenon may have been favored by regional extension tectonics that enhance the circulation of groundwater and salt dissolution. (C) 2003 Elsevier B.V. All rights reserved

Geology and models of salt extrusion at Qum Kuh, central Iran, 2004, Talbot C. J. , Aftabi P. ,
Profiles through the summit of a small nearly axisymmetric extrusion of Oligocene and Miocene salt, and simple analogue models of it, simulate the profiles of piles of ductile nappes extruded from convergent orogens. The salt extrudes from a reactive diapir along a major strike-slip fault at about 82 mm a(-1) and rises 315 m above the central plateau of Iran. The salt has the distinctive smooth profile of a viscous fountain in which an asymmetric apron of allochthonous salt gravity-spreads over its surroundings from a summit dome. Curtain folds developed in the source layer extrude from the diapir and are refolded by major recumbent folds with circumferential axes that simulate nappes. Minor flow folds with circumferential axes refold major folds in the top 10-50 m of surficial salt. Master joints > 100 m long indicate brittle failure of dilated salt by regional stress fields. Tuned to the dimensions of Qum Kuh, analytical and analogue models of viscous extrusions constrain the dynamic salt budget and a time of extrusion of at least 42000 years. New analogue models suggest that the number, amplitude and spacing of major recumbent folds within the extruded salt (and ductile nappe piles) record the number, amount and relative timing of fluctuations in the driving forces

Geological-evolutionary model of a gravity-induced slope deformation in the carbonate Central Apennines (Italy), 2004, Martino S. , Prestininzi A. , Mugnozza G. S. ,
This paper discusses the findings from a study conducted on gravity-induced deformations occurring along the SW slope of Mount Nuria linking the village of Pendenza (Rieti, Italy) to the area of San Vittorino, in the alluvial plain of the Velino river, where important infrastructures are present. The dominantly carbonate composition of the rocks outcropping along the slope, the occurrence of a main spring fed by a regional karst aquifer and the interaction of gravity-induced deformations with buildings and infrastructures resting on the slope or located at its base make the investigated case extremely interesting and reflective of phenomena that are common in similar geological-hydrogeological conditions. Insights from this case and their use for the construction of a 'geological-evolutionary model' shed more light on the complex interactions existing between jointed carbonate rocks, seepage, karst dissolution, genesis of gravity-induced deformations and their evolution in space and time, through the analysis of stress-strain conditions within the slope. According to the selected methodological approach, data from detailed geological, geomorphological and geomechanical surveys were integrated with those from laboratory tests and from a complex slope monitoring system. From the results of the study it was possible to: i) refer the investigated phenomena to gravity-induced deformations on the slope scale; ii) build a representative 'geological-evolutionary model' and iii) develop an analytical approach to assess the hazard represented by these deformations for local buildings and infrastructures. The identification of different hazard conditions can help define the type and value of possible mitigation efforts. The investigated case also provided inputs for testing new approaches to the geomechanical characterization of rock masses, to the description of their jointing and to the correlation of their main discontinuities with tectonic and gravity-induced elements

Review on the use of natural cave speleothems as palaeoseismic or neotectonics indicators, 2005, Gilli E,
Collapses that affect cave speleothems have frequently been attributed to earthquakes, although this has not been proved. Observations after an earthquake and laboratory tests indicate that only slender speleothems break under coseismic solicitation. Other causes as subsidence, decompression and creeping of ice or cave sediments explain most of the breaks. Tectonics is also a major cause of speleothems breakages and it is possible to detect minute movements of faults. It seems possible to make the difference between brutal coseismic movements and aseismic slow ones. However, the interpretation is often difficult, as the damage can also be caused by gravity tectonics or glacitectonics. To cite this article: E. Gilli, C. R. Geoscience 337 (2005)

From the geological to the numerical model in the analysis of gravity-induced slope deformations: An example from the Central Apennines (Italy), 2005, Maffei A. , Martino S. , Prestininzi A. ,
This paper presents the findings from a study on gravity-induced slope deformations along the northern slope of Mt. Nuria (Rieti-Italy). The slope extends from the village of Pendenza to the San Vittorino plain and hosts the Peschiera River springs, i.e. the most important springs of the Central Apennines (average discharge: about 18 m(3)/s). Detailed geological-geomorphological and geomechanical surveys, supported by a site stress-strain monitoring system and laboratory tests, led us to define the main evolutionary features of the studied phenomena. Based on the collected data, a 'geological-evolutionary model' was developed with a view to identifying a spatio-temporal correlation between relief forms, jointing of the rock mass and its stress conditions. The geological-evolutionary model was expected to improve numerical simulations and to test our assumptions. The numerical model also allowed us to simulate changes in the stress-strain conditions of the rock mass and correlate them with jointing, seepage, as well as with site-detected and site-monitored forms and deformations. In particular, significant relations between seepage, tensile stresses within the rock mass, karst solution and collapse of cavities were identified. (c) 2005 Elsevier B.V. All rights reserved

Late glacial to Holocene climate and sedimentation history in the NW Black Sea, 2005, Bahr A, Lamy F, Arz H, Kuhlmann H, Wefer G,
Gravity cores from the continental slope in the northwestern Black Sea were studied using high-resolution stable isotope, grain size and XRF-scanning data. The measurements provide a 30 000 years AMS 14C-dated record of variations in the hydrological regime of the Black Sea and give insight into changing paleoenvironments in the surrounding areas. Stable climatic conditions during the Last Glacial Maximum were followed by a series of meltwater pulses most likely originating from the Scandinavian ice sheet between 18 000 and 15 500 yr BP.1 This meltwater input rose the level of the Caspian Sea to a point that Caspian water could spill into the Black Sea via the Manych-depression north of the Caucasian mountains. High-frequency oscillations in the XRF-data during this period suggest a probable link to the arctic climate regime. Later, during the Bolling/Allerod and the early Holocene, prevailing high temperatures led to authigenic calcite precipitation through increased phytoplankton activity, interrupted by the Younger Dryas and the '8200 yr BP cold event' with dominant clastic sedimentation

The use of microgravity for cavity characterization in karstic terrains, 2005, Styles P. , Mcgrath R. , Thomas E. , Cassidy N. J. ,
Microgravity is the interpretation of changes in the subsurface density distribution from the measurement of minute variations in the gravitational attraction of the Earth. As a technique, it is particularly suited to the investigation of subsurface structures, mapping of geological boundaries and, most importantly in this case, the location and characterization of voids or cavities. Gravity variations due to the geological/petrophysical changes associated with fracturing and changes in pore composition are superimposed upon much larger variations due to elevation, latitude, topography, Earth tides and regional geological variations. However, these external changes can be modelled or monitored with sufficient accuracy to be removed from the data. With the recent development of high-resolution instruments, careful field acquisition techniques and sophisticated reduction, processing and analysis routines, anomalies as small as 10 microgal can be detected and interpreted effectively. This paper describes the state-of-the-art' application of the microgravity technique for the detection and characterization of karstic cavities in a variety of limestone terrains, including the Carboniferous Limestone of the United Kingdom and Eire and the coral limestones of the Bahamas. The case study examples show how the recorded gravity anomalies have revealed the location of density variations associated with underground cave systems and, ultimately, provided information on their depths, shapes and morphology from a combined analysis of their spectral content, characteristic gradient signatures and modelling responses. In addition, mass deficiencies have been estimated, directly from the anomaly map, by the use of Gauss's theorem without any prior knowledge of the exact location, or nature, of the causative bodies

The search for Palmer's Chamber, Lamb Leer, Somerset, United Kingdom, 2006, Butcher, Antony, Phillip J Murphy, Simon Beaney And Roger Clark.
During the late 1930s and 1950s a series of geophysical resistivity measurements were acquired by Professor Leo Palmer of Hull University over the Lamb Leer cave system (referred to as Lamb Lair by Palmer), which is located within the Mendip Hills, Somerset. Through his surveys, Professor Palmer reportedly delineated a resistive zone that he believed to correspond to the location of the Great Chamber of Lamb Leer, a 30m-diameter cavity located at 35m below ground level. Additionally, he concluded that a further large cavern of similar size existed some 100m northeast of the Great Chamber. In an attempt to confirm the existence and establish the nature of "Palmer's Chamber", a series of resistivity and microgravity profiles were carried out during the summers of 2004 and 2006. The resistivity survey confirmed the presence of a resistive anomaly within the vicinity of "Palmer's Chamber"; however the resulting microgravity data do not suggest the presence of a mass deficiency feature that would be expected over a significant void.

Aroca (domaine marin ctier, Pays basque, France) : un karst continental ennoy par les transgressions maritimes quaternaires, 2007, Vanara Nathalie , Perre Alain, Pernet Marc, Latapie Serge, Jaillet Stphane, Martine Olivier
AROCA (LITTORAL, BASQUE COUNTRY, FRANCE): A CONTINENTAL KARST DROWNED BY QUATERNARY MARITIME TRANSGRESSIONS. The rocky formations in shallow areas of the Atlantic coast are hardly known. Studies are rare because of the difficulties of direct observation (diving in always agitated, troubled water, depth between 20 and 40 m). Our first step was to make a detailed topography of a submarine plateau named Aroca, 4 km off Socoa harbour (bay of Saint-Jean-de-Luz). This plateau was already known for having a large variety of forms within a small surface (150 x 100 m). We gave names to most remarquable formations and defined five main characteristic zones: - in the exokarstic domain 1/ a top surface with channels, 2/ a dismantled surface with pinnacles; - in the endokarstic domain 3/ caves, galleries, arches; - at the limits 4/ three inclined plans, west, north and east, 5/ a cliff to the south. A typology of forms shows a predominance of ablation reliefs: aplanation, over-deepened channels, covered rooms and galleries, arches, residual pinnacles. Deposit accumulations regroup chaotic breakdown blocks, pebble accumulations and sand covers. Statement of explanations requires recognition of the nature and age of the outcrops and succession of erosional agents during the Pleistocene. Rocks are dated from Ypresien (limestones) to Bartonian (marls). Continental erosion during sea regressions is responsible of caracteristic landforms and deposits; for example wall banks, allochthonous pebbles The currently active marine erosion during sea transgressions is due to storms, tide, dissolution, biochemical action (lithophages) and gravity. We propose a paleogeographic reconstitution. After an essentially calcareous sedimentation in Eocene and an essentially marly sedimentation in Oligocene, the sea recedes during Miocene. From then, the platform, henceforward above the water, is subject to meteoric erosion. In Pliocene, evolution of the massif is isovolumic (under a marly cover and with a low hydraulic gradient). During the lower and middle Pleistocene, the erosion of the marly cover goes on. During the upper Pleistocene, the wurmian (18000 BP) marine regression allows entrenchment of the hydrographic system thanks to an increase of hydraulic gradients (classic functional karst). From 15000 years onwards, a general transgression of sea level happens by successive steps. During the Boreal, a break in transgression allows the formation of a paleo-shore at 20 to 30 m, inducing a peneplanation phase in the tidal or infratidal zone. From 7500 BP onwards, a a rapid transgression from 23 to 8, then a slower one from 8 to the present level stops karstification on the massif. At present, only marine abrasion is active and tends to obliterate the previously built landforms.

Assessment of cover-collapse sinkholes in SW Sardinia (Italy), 2007, Ardau F, Balia R, Bianco M, De Waele J,
The SW part of Sardinia has been afflicted, in recent years, by several cover-collapse sinkholes mostly occurring in low-density population areas. The study area, that lies in the Iglesiente-Sulcis region, is characterized by the cropping out of the Palaeozoic basement related to the South European Hercynian chain, covered with Tertiary-Quaternary sediments. The main rock types that crop out are Palaeozoic metasandstones, metadolostones, metalimestones, shales and metaconglomerates, and Tertiary-Quaternary fluvial-lacustrine continental sediments. The combined application of several geophysical techniques, integrated with boreholes and geotechnical as well as hydrogeological measurements, proved to be very useful and promising in defining in detail the geological context in which each sinkhole has formed. Moreover, the gravity method, even when used alone, proved to be very effective in detecting the regional geological structures to which sinkholes are related. Eventually, the historical analysis of phenomena, the geological knowledge of the Iglesiente-Sulcis area and the results of properly designed geophysical surveys allows the most probable areas for cover-collapse sinkholes to occur in the future to be determined. In fact, this research pointed out that the depth of the sediment-covered Palaeozoic bedrock is one of the major constraints in delimiting hazardous areas, leading to the construction of a preliminary hazard map. This map shows a belt of high risk, and also suggests the areas in which further geophysical and geotechnical investigations should be carried out to estimate the depth of the bedrock

The legend of carbon dioxide heaviness, 2009, Badino G.
The false legend of carbon dioxide traps resulting from the weight of carbon dioxide gas is disproved. In spite of water-vapor lightness in comparison with air, no water-vapor trap exists on cave ceilings. In fact, underground atmospheres with specific compositions are not related to gravity, but to the absence of any air movement around the gas sources. The process of double diffusion of oxygen and carbon dioxide during organic compound decomposition in still air is shown to be significant. This phenomenon can form atmospheres that are deadly due to oxygen deficiencies and poisonous because of excess carbon dioxide. Carbon dioxide storage behaves like a liquid and can flow or can be poured, as cold air can, but these are typical transient processes with no relation to a caves foul air formation.

The genesis of cave rings explained using empirical and experimental data, 2009, Nozzoli F. , Bevilacqua S. , And Cavallari L.
A cave ring is a faint speleothem consisting in a thin circle on the floor symmetrically surrounding a water drop impact point. Two different mechanisms seem to be responsible for cave ring formation: the drop splash at the floor, for the splash rings, and the ejection of a secondary droplet during the fall, for the fall down rings. A systematic investigation of 67 speleothem rings discovered in five different caves in central Italy was conducted. The data show compatibility with a common nature for all the observed rings. For the observed rings, the hypothesis of a falling secondary droplet origin is confirmed and the hypothesis of a primary drop splash is rejected. The trajectory of a secondary droplet has been measured, and the collected data suggest that the secondary droplets originate from a primary drop breakup at a distance y0 5 142.7 6 7.2 cm from the stalactite tip. Assuming this spontaneous breakup hypothesis, the velocities ratio b 5 uy/ux 5 25.5 6 1.6 at the breakup time was measured. Finally, the collected ring data (5-cm- to 50-cm-diameter range) exhibit a negative curva- ture trajectory. The large departure from a gravity dominant parabolic trajectory suggests other forces, such as air friction or lift force, are at work on the small secondary droplets.

Microscopic fungi isolated from the Domica Cave system (Slovak Karst National Park, Slovakia). A review, 2009, Novakova A.
A broad spectrum, total of 195 microfungal taxa, were isolated from various cave substrates (cave air, cave sediments, bat droppings and/or guano, earthworm casts, isopods and diplopods faeces, mammalian dung, cadavers, vermiculations, insect bodies, plant material, etc.) from the cave system of the Domica Cave (Slovak Karst National Park, Slovakia) using dilution, direct and gravity settling culture plate methods and several isolation media. Penicillium glandicola, Trichoderma polysporum, Oidiodendron cerealis, Mucor spp., Talaromyces flavus and species of the genus Doratomyces were isolated frequently during our study. Estimated microfungal species diversity was compared with literature records from the same substrates published in the past.

A terminological matter: paragenesis, antigravitative erosion or antigravitational erosion ?, 2009, Pasini G.
In the speleological literature three terms are utilized to designate the ascending erosion: paragenesis (= paragnsis, coined in 1968), antigravitative erosion (= erosione antigravitativa, coined in 1966) and antigravitational erosion (wrong English translation of the Italian term erosione antigravitativa, utilized later on). The term paragenesis should be abandoned because of the priority of the term erosione antigravitativa - on the ground of the law of priority and because of its ambiguous etimology. On the other hand, the term antigravitational erosion should be forsaken in favour of the term antigravitative erosion, given the meaning that the terms gravitation and gravity have in Physics. Therefore, to designate the phenomenon of the ascending erosion there would be nothing left but the term antigravitative erosion. The antigravitative erosion process and its recognizability are illustrated. Examples of caves with evident antigravitative erosion phenomena, developed in different karstifiable rocks and in several parts of the world, are given. It is recalled that the antigravitative erosion is a phenomenon well-known since 1942 and widely proven and supported, and that it is relatively easy in many cases - to recognize the antigravitative origin of karstic passages. It is stressed that the antigravitative erosion is an important phenomenon, exclusive of the karstic caves and unique in nature.

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