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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 Kluft is see aisle.?

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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 dependence (Keyword) returned 47 results for the whole karstbase:
Showing 16 to 30 of 47
SEISMIC-electric effect method on guided and reflected waves, 2000, Boulytchov A,
Measurements of seismic-electric effect (SEE) in laboratory and field conditions either on guided or reflected waves were carried out. SEE signals were distinctly traced on receiver that was advantage for treatment. The SEE method was successfully used on reflected waves in a deep cave interior to determine the sediment thickness and on karst massifs to predict the dome cave cavities. In similar difficult attainable places the method is preferable to be used for it does not require a complex apparatus. SEE values dependence on productivity of kimberlites rocks, on permeability of oil-water saturated collectors were investigated on guided waves in laboratory experiments. SEE value allows to distinguish oil, oil-water saturated rocks and only water-saturated rocks from each other. SEE value allows to differ productive kimberlites from non productive ones and from surrounding rocks

Speleogenesis in gypsum, 2000, Klimchouk A.
The main differences between the solutional properties of gypsum and those of calcite lie in the much higher solubility of gypsum, and in dissolution kinetics of gypsum which is solely diffusion controlled. Unlike calcite, no change of kinetic order occurs with an increase in concentration. Initiation of long lateral flow paths through gypsum is virtually impossible due to the rapid rate of dissolution; no kinetic mechanisms allow slow but uniform dissolutional enlargement throughout the flow paths. Near the surface, fissures are already wide enough for cave development to occur, which is extremely competitive due to rapid dissolution kinetics and the strong dependence of enlargement rates on flow velocity and discharge. Thus caves in gypsum in exposed settings are mainly linear or crudely branching, rapidly adjusting to the contemporary geomorphic setting and available recharge. Vertical pipes or pits form in the vadose zone. No deep phreatic development and no artesian development by lateral flow from distant recharge areas can occur. However, cave origin and development does occur in deep-seated confined settings where gypsum beds in stratified sequences are underlain by, or sandwiched between poorly soluble aquifers. Two situations support cave origin in gypsum in deep-seated settings: (1) transverse flow through gypsum between overlying and underlying aquifers, and (2) lateral flow in an insoluble but permeable aquifer underlying a gypsum bed. The former situation generates either maze caves where uniformly distributed fissure networks exist in the gypsum, or discrete voids where the otherwise low-fissured gypsum is disrupted by prominent tectonic fractures. If considerable conduit porosity has been created in a deep-seated setting, it provides ready paths for more intense groundwater circulation and further cave development when the gypsum is uplifted into the shallow subsurface. Thick and low-fissured sulfate strata can survive burial with no speleogenesis at all where surrounded by poorly permeable beds. When exposed to the surface, such gypsum deposits undergo speleogenetic development with no inherited features, presenting the pure line of open karst.

Intra- and inter-annual growth rate of modern stalagmites, 2001, Genty D, Baker A, Vokal B,
We measure the factors that determine growth rate (temperature, drip rate, calcium ion concentration) for 31 waters that feed stalagmites within six cave systems throughout Europe. Water samples were collected at a frequency of at least month. to permit the modelling of both inter- and intra-annual growth rate variations, utilising the theory of Wolfgang Dreybrodt (Chem. Geol. 29 (1980) 89-105; Chem. Geol, 32 (1981) 237-245; Dreybrodt, W., 1988, Processes in Karst Systems. Springer-Verlag, Berlin 288 pp.). Inter-annual growth rates were measured using the stalagmites that were associated with the analysed water samples; growth rate was determined from annual lamina counting, specific time markers within the stalagmites, and location of bomb C-14. When compared to theoretically predicted values, a good agreement between theoretical and measured stalagmite growth rates is observed (R-2 = 0.69). When compared to site climate and geochemical parameters, a good correlation is observed between measured growth fate and mean annual temperature for five sites (R-2 = 0.63) and dripwater calcium content (R-2 = 0.61), but not drip rate (R-2 = 0.09). The good correlation with both calcium and temperature is due to soil CO, production being primarily determined by surface temperature and soil moisture. However, when we compare our data to that in the Grotte de Clamouse, a site that has little soil cover, we observe that the growth rate-temperature relationship breaks down due to either the lack of soil CO, production or prior calcite: precipitation. Intra-annual data demonstrates that maximum growth rate occurs when calcium concentrations are high, and that this occurs under different seasons depending on the hydrology of each site. Our results demonstrate a stronger dependence of intra-annual stalagmite growth rate on dissolved calcium ion concentrations than drip rate for the range of drip rates investigated here (0.01 < t < 2drip s(-1)), but for lower drip rates, this factor becomes important in controlling growth rate. We suggest that for well-monitored acid -understood sites, stalagmite growth rate variations can provide useful information for palaeoclimate reconstruction. (C) 2001 Elsevier Science B.V. All rights reserved

Structural Bases for Shaping of Dolines, 2001, Č, Ar Jož, E

By a precise registration of geological structural elements (the location of beds and to what degree the rock is fractured) and by observation of some morphological properties one may define for each individual doline, either directly or by combining the data known in nearby dolines and their vicinity, the geological bases which give the foundations for its present location, shape and size. On such a basis we prepared a descriptive-genetic classification of dolines and I defined 8 basic types of dolines (labelled from A to H, Fig. 1). In nature pure types are rare; usually combinations occur. The findings relate to dolines in different carbonate rocks and carbonate clastites. Hence it follows that the genesis of dolines cannot be simplified into one general model but all the models are »valid« (corrosion, collapse, climatic) combining among them and intertwined by interdependence of circumstances.

Simulating time-varying cave flow and water levels using the Storm Water Management Model, 2002, Campbell Cw, Sullivan Sm,
The Storm Water Management Model (SWMM) is an Environmental Protection Agency code used to estimate runoff through storm water drainage systems that include channels, pipes, and manholes with storage. SWMM was applied to simulate flow and water level changes with time for a part of Stephens Gap Cave in Jackson County, Alabama. The goal of the simulation was to estimate losses from a surface stream to the cave. The cave has three entrances that can remove water from the surface stream. These entrances connect through several passages to an 8-m (27-ft) high waterfall in a dome room. After a storm, the walls of this dome room had leaves on the wall as high as 4.6 m (15 ft) above the floor. The model showed that the height of the leaves did not represent a water level that could have occurred following any recent storm.Campbell, Livingston and Garza in 1997 developed the CLG model to estimate losses from karst surface streams. This model treats losses as pipe flow from a reservoir and gives the loss flow rate as ~h0.5 where h is the depth of flow in the surface stream. Losses to Stephens Gap Cave calculated with SWMM varied as h1.8. This depth dependence is more characteristic of flow over a weir than of pipe flow.The SWMM-calculated losses to Stephens Gap Cave showed no hysteresis, that is, the rising and falling limbs of the stage-discharge plot followed the same curve. Loss curves with significant hysteresis are difficult to simulate with simple models such as CLG or a weir flow model. However, an SWMM model of a simple hypothetical cave demonstrated that storage in Stephens Gap Cave is far below that required to cause hysteresis. Losses from many karst surface streams can probably be adequately estimated with a calibrated weir flow model. The utility of SWMM for analyzing cave flows was established. SWMM produced stable solutions with very low continuity errors for this cave

Analytical 1D dual-porosity equivalent solutions to 3D discrete single-continuum models. Application to karstic spring hydrograph modelling, 2002, Cornaton F, Perrochet P,
One-dimensional analytical porosity-weighted solutions of the dual-porosity model are derived, providing insights on how to relate exchange and storage coefficients to the volumetric density of the high-permeability medium. It is shown that porosity-weighted storage and exchange coefficients are needed when handling highly heterogeneous systems-such as karstic aquifers-using equivalent dual-porosity models. The sensitivity of these coefficients is illustrated by means of numerical experiments with theoretical karst systems. The presented ID dual-porosity analytical model is used to reproduce the hydraulic responses of reference 3D karst aquifers, modelled by a discrete single-continuum approach. Under various stress conditions, simulation results show the relations between the dual-porosity model coefficients and the structural features of the discrete single-continuum model. The calibration of the equivalent 1D analytical dual-porosity model on reference hydraulic responses confirms the dependence of the exchange coefficient with the karstic network density. The use of the analytical model could also point out some fundamental structural properties of the karstic network that rule the shape of the hydraulic responses, such as density and connectivity. (C) 2002 Elsevier Science B.V. All rights reserved

Detection of sinkholes developed on shaly Ordovician limestones, Hamilton County, Ohio, using digital topographic data: Dependence of topographic expression of sinkholes on scale, contour interval, and slope, 2003, Applegate, P.
The Ohio Geological Survey has recently published a map showing the locations of known and probable karst in Ohio. The map shows some areas of karst developed on the extremely shaly Ordovician limestone of Hamilton County, in the southwestern corner of the state. Detailed mapping of these sinkholes in Mt. Airy Forest, a municipal park near Cincinnati, shows that they occur only where the lower 10 m of the Corryville Member of the Grant Lake Formation is the surface bedrock. Of the many sinkholes in the study area, only one is evident on the 1:24,000 USGS topographic map. The expression of sinkholes on contour maps is dependent on the size of the sinkhole, as well as the scale of the map, the contour interval at which the topography is sampled, and the slope of the ground surface around the sinkhole. It is possible to determine the minimum size of sinkhole which will consistently be expressed on a given part of a contour map. Conversely, it is also possible to determine the scale and contour interval which will be necessary to consistently indicate the presence of sinkholes of a given minimum size.

Dam sites in soluble rocks: a model of increasing leakage by dissolutional widening of fractures beneath a dam, 2003, Romanov D. , Gabrovsek F. , Dreybrodt W. ,
Water flowing through narrow fissures and fractures in soluble rock, e.g. limestone and gypsum, widens these by chemical dissolution. This process, called karstification, sculptures subterranean river systems which drain most of their catchment. Close to dam sites, unnaturally high hydraulic gradients are present to drive the water impounded in the reservoir downstream through fractures reaching below the dam. Under such conditions, the natural process of karstification is accelerated to such an extent that high leakage rates may arise, which endanger the operation of the hydraulic structure. Model simulations of karstification below dams by coupling equations of dissolutional widening to hydrodynamic flow are presented. The model scenario is a dam 100 in wide in limestone or gypsum. The modelling domain is a two-dimensional slice 1 m wide directed perpendicular to the dam. It extends 375 in vertically and 750 in horizontally. The dam is located in its center. This domain is divided by fractures and fissures into blocks of 7.5 x 7.5 x 1 m. The average aperture width of the fractures is 0.02 cm. We performed model runs on standard scenarios for a dam site in limestone with the height H of impounded water 150 in, a horizontal impermeable apron of width W=262 m and a grouting curtain reaching down to a depth of G=97 m. In a second scenario, we changed these construction features to G=187 m and W=82 m. To calculate widening of the fractures, well-established experimental data on the dissolution of limestone and gypsum have been used as they occur in such geochemical settings. All model runs show similar characteristic behaviour. Shortly after filling, the reservoir exhibits a small leakage of about 0.01 m(-3) s(-1), which increases steadily until a breakthrough event occurs after several decades with an abrupt increase of leakage to about 1 m(3) s(-1) within the short time of a few years. Then, flow in the fractures becomes turbulent and the leakage increases to 10 m(3) s(-1) in a further time span of about 10 years. The widths of the fractures are visualized in various time steps. Small channels propagate downstream and leakage rises slowly until the first channel reaches the surface downstream. Then breakthrough occurs, the laminar flow changes to turbulent and a dense net of fractures which carry flow is established. We performed a sensitivity analysis on the dependence of breakthrough times on various parameters, determining breakthrough. These are the height of impounded water H, the depth G of grouting, the average aperture width a(0) of the fractures and the chemical parameters, which are c(eq) the equilibrium concentration of Ca with respect to calcite and the Ca-concentration c(in) of the inflowing water. The results show that the most critical parameter is a(0). At fracture aperture widths of 0.01 cm, breakthrough times are above 500 years. For values of a(0)>0.02 cm, however, breakthrough times are within the lifetime of the structure. We have also modelled dam sites in gypsum, which exhibit similar breakthrough times. However, after breakthrough, owing to the much larger dissolution rates of gypsum, the time until unbearable leakage is obtained, is only a few years. The modelling can be applied to complex geological settings, as phreatic cave conduits below the dam, or a complex stratigraphy with varying properties of the rock with respect to hydraulic conductivity and solubility. A few examples are given. In conclusion, our results support the assumption that increasing leakage of dam sites may be caused by dissolutional widening of fractures. (C) 2003 Elsevier Science B.V. All rights reserved

Evolution of Karst Aquifers in Natural and Man Made Environments: A Modeling Approach. Ph.D. thesis, 2003, Romanov, Douchko

The evolution of karst aquifers under various hydrological and chemical boundary conditions is studied.
In the first part the influence of exchange flow from a prominent fracture into a two-dimensional network of fissures is compared to the evolution of a fracture isolated from this net. The modeling domain is 742.5 m long and 375 m wide dissected by fractures into 100 by 51 blocks. The wide prominent fracture extends along its center, thus constituting a part of the network. Under constant head conditions between the left and the right hand side of the domain it looses flow into the network. We have studied the influence of the fracture widths of the fine net to the breakthrough time (BT) of the system. Because of loss of flow from the central fracture to the net, aggressive solution from the input enhances dissolution and breakthrough times are reduced. This effect is most effective, when the aperture width of the fine net is only smaller by about 1% than the widths of the prominent fracture, such that a large amount of water can flow into the net. To obtain further information on the processes involved, an isolated one-dimensional fracture with an additional single point of outflow from it, is investigated.
As an application of the results above, the evolution of a karst aquifer below dam sites is studied. The modeling domain is a 2D, 1 m wide vertical section of soluble rock (gypsum and limestone), perpendicular to the dam. The block extends 750 m horizontally and 375 m vertically. It is divided by fractures and fissures into blocks of 7.5 m x 7.5 m x 1m. The chemical composition of the inflowing water is equal at all input points. Because of dissolution along the fractures, a large zone of increasing permeability is created below the structure, causing high unbearable water losses from the dam site and also endangering the mechanical stability of the dam. The dependence of BT on the basic parameters - the height of the impounded water, the depth of the grouting curtain, the initial aperture widths of the fractures and the fissures, and the chemical parameters of the inflowing water (equilibrium concentration with respect to calcite and input concentration) is investigated. For fracture aperture widths larger than 0.02 cm breakthrough occurs within the lifetime of the structure.
In the second part the effect of chemical boundary conditions on the evolution of a karst aquifer is studied. The model domain is 500 m x 225 m, divided into blocks of 5 m x 5 m x 1 m by fracture network. There are two input points at constant head (25 m) at the inflow side of the block. The outflow side is open at constant head – 0 m. The hydrological boundaries are equal for all simulated scenarios. The chemical composition of the inflowing water at both inputs is varied, and the reaction of the aquifer is studied. Mixing corrosion is the reason for zones of increased permeability deep inside the aquifer along the boundary, where the solutions mix. The influence of mixing corrosion for various values of the input Ca concentration is studied. The results show two types of evolution. Breakthrough (BT) governed evolution – for values of cin<0.96?ceq, and mixing corrosion (MC) - governed evolution for values of cin>0.96?ceq. The BT - type is characterized by enlarged pathways connecting an inflow point with the outflow boundary. For increasing values of the input concentrations the effect of MC becomes stronger. For high Ca concentrations, MC is dominating. There is no considerably widened connection between the inflow points and the out flow boundary. but an enlarged channel along the mixing zone is observed. The timescale for this type of evolution is considerably longer. For solutions saturated with respect to calcite, the mixing zone is the only area of widening inside the aquifer.

Numerical analysis of conduit evolution in karstic aquifers. PhD Thesis, 2003, Annable, W. K.

Fractured and solutionally enhanced carbonate aquifers supply approximately 20 percent of the Worlds potable water supply. Although in rare cases these geologic settings can geochemically evolve into conduits which are of sufficient size to be explored and interpreted by researchers, the majority of the solutionally enlarged networks providing fresh water supplies remain too small to be directly measured. As such, we rely upon indirect hydraulic testing and tracer studies to infer the complexity and size of such aquifers. Because solutionally enhanced (karstic) aquifers have multiple scales of porosity ranging from matrix flow, fracture flow and open channel conduit flow, they are particularly vulnerable to contamination due to the high rates of chemical transport. In this study, a numerical model which solves for the variably-saturated flow, chemically-reactive transport and sediment transport within fractured carbonate aquifers has been developed to investigate the evolution of proto conduits from discrete fractures towards the minimum limits of caves which can be explored. The model results suggest that, although potentiometric surfaces can be of assistance in forecasting the possible locations of proto conduits at depth, many conduits are never detected using conventional observation wells relying upon hydraulic head data. The model also demonstrates the strong dependence in the pattern of vertical jointing on how conduits may evolve: fractures oriented similar to the mean groundwater flow direction show conduits evolving along the vertical fracture orientation; however, vertical fractures that differ significantly from the mean groundwater flow direction have vastly more complex dissolution networks. The transport of fine-grained sediments within the fractures has been shown to reduce the rates of conduit development in all but the highest velocity regions, resulting in simplified conduit networks, but at accelerated dissolution rates. The fully-coupled advective-dispersive and reactive chemistry equations were employed strictly with equilibrium reactions to simulate calcite dissolution. This study further shows that higher order kinetics in the form of the kinetic trigger effect of White (1997) are not required if diffusion between the rock matrix and the fracture surfaces account for multi-component matrix diffusion effects between the evolving conduits and the carbonate rock matrix according to the diffusional characteristics of the fractured rock system at hand.

Spelologische Charakterisierung und Analyse des Hochschwab-Plateaus, Steiermark., 2004, Plan, L.
The Hochschwab is one of the major karst massifs of the Northern Calcareous Alps (NCA), situated in the north of the Austrian province of Styria and provides freshwater for the city of Vienna. Karstmorphological mapping of 44 km of its plateau brought the discovery of 770 new caves. Together with formerly recorded caves and possible caves detected on aerial photographs a total of 1284, mainly vertical objects are integrated into a GIS. In combination with additional digital datasets, statistical analyses are performed considering the spatial distribution of cave density as well as the dependence on altitude and lithology. Beside this, the most important caves within the study area are characterised. The investigated caves are mainly pits and vertical canyons which developed in the vadose zone. Phreatic cave levels associated with former valley floors, which are common in the NCA, do not exist in the Hochschwab. A few caves of phreatic origin developed above aquitard geological units. The average cave density in the investigation area is 24 objects/km. In glacially strongly overprinted areas it increases to more than 400 caves per km. Remarkable facts of the dependence on lithology are that the limestone of the Dachstein Formation does not show an increased cave density. In contrast, the diverse facies of the limestones of the Wetterstein Formation exhibit major differences.[Hundsbodenschacht (1744/11), G'hacktsteinschacht (1744/14), Furtowischacht (1744/310), Sargdeckelschacht (1744/363), TremmelSchacht-413 (1744/413), EBNK-Schacht (1744/426), Schrgschacht (1744/442), Hirschgrubenhhle (1744/450), Melkbodeneishhle (1745/1), Eis-Schacht-39 (1745/39), Spaltenschacht (1745/43)]

Activators of luminescence in speleothems as source of major mistakes in interpretation of luminescent paleoclimatic records, 2004, Yavor Shopov
This work summarizes the main results of the operation of the International Program "Luminescence of Cave Minerals" of the commission on Physical Chemistry and Hydrogeology of Karst of UIS of UNESCO in the field of activators of speleothem luminescence. It discusses Activators of Luminescence in Speleothems as a source of major mistakes in the interpretation of luminescent paleoclimatic records. It demonstrates the existence of 6 types of luminescence of speleothems and cave minerals in dependence of the type of the luminescence center and its incorporation in the mineral. 24 different activators of photoluminescence of speleothem calcite and 11 of aragonite are studied. This paper demonstrates that it is impossible to produce reliable Paleotemperature or Past Precipitation records from luminescence of speleothems without establishing the organic origin of the entire luminescence of the particular sample.

Stalagmite growth and palaeo-climate: an inverse approach, 2004, Kaufmann G. , Dreybrodt W. ,
The growth of stalagmites is controlled by climatic conditions such as temperature, soil activity, and precipitation. Hence, a stalagmite stratigraphy reflects fluctuations of palaeo-climate conditions on various time scales, from annual variations to ice-age cycles. However, no attempt has been made to infer palaeo-climate fluctuations from the stratigraphy itself We describe the complicated growth of a stalagmite with a simple mathematical model, in which both the growth rate and the equilibrium diameter of stalagmites are functions of palaeo-climate variables. Hence, inverting a given stalagmite stratigraphy in terms of growth rate and equilibrium diameter can in principle recover the palaeo-climate signal. The strongly nonlinear dependence of these two geometrical parameters, however, limits the success of a formal inversion of stratigraphical data. In this paper, we explore the resolving power of both growth rate and equilibrium diameter data for the palaeo-climate signals temperature, carbon-dioxide concentration, and precipitation. We use numerically generated stalagmite stratigraphies as observational data, thus we know beforehand the palaeo-climate signal contained in the stratigraphic record. Our results indicate that both variations in carbon-dioxide concentrations (as a proxy of soil cover) and drip interval (as a proxy of precipitation) can be recovered from the stratigraphy. However, temperature variations are poorly resolved. (C) 2004 Elsevier B.V. All rights reserved

Lateglacial and Holocene sea level changes in semi-enclosed seas of North Eurasia: examples from the contrasting Black and White Seas, 2004, Kaplin Pavel A. , Selivanov Andrei O. ,
A comparison of the Black and White Seas, which differ in their tectonic, glacial and climatic history but which share a strong dependence upon limited water exchange with the world ocean, represents an opportunity for the identification of major factors controlling sea level changes during the Lateglacial and Holocene and for the correlation of these changes. Existing data were critically analyzed and compared with the results of geological, geomorphological and palaeohydrological studies obtained by the present authors during the past two decades.We conclude that glacioeustatic processes played a major role in relative sea level changes on most coasts of both areas. However, along several coastlines, other factors overwhelm glacioeustasy during some time intervals. In the Black Sea, water level rose from its minimum position, -100-120 m, at 18-17 ka BP, to -20-30 m at nearly 9 ka BP. In the White Sea, the decreasing trend in relative sea level is well illustrated on the Kola Peninsula and in Karelia, subject to glacioisostatic emergence. A drastic sea level fall from to -25 m occurred with the drainage of glacial lakes in the eastern White Sea (12.5-9.5 ka BP).The Black and White Sea histories changed drastically in the early Holocene or in the beginning of the middle Holocene (9.5-7.5 ka BP) due to the intrusion of water from the Mediterranean and the Barents seas, respectively. During this period, the White Sea developed under the strong influence of the formation of 'ice shelves' and 'dead ice' blocks, retreating glaciers, as well as of glacioisostatic and related processes. The Black Sea history, however, was determined by water exchange with the Mediterranean via the shallow Dardanelles and Bosporus straits (outflow from the Black Sea 10-9.5 ka BP and inflow from 9-7.5 ka BP according to various data), and, partially, by river discharge variations caused by climatic changes on the Russian Plain. The hypothesis of a catastrophic sea level rise from -120-150 to -15-20 m nearly 7550 calendar years BP is not supported by our data. Water intrusion from the Mediterranean was fast but not catastrophic.In the Black Sea, periods of high sea levels after the intrusion of Mediterranean waters are dated from four sedimentary complexes, Vityazevian, Kalamitian, Dzhemetian and Nymphaean, from nearly 7.5, 7-6, 5.5-4.5 and 2.2-1.7 ka BP, respectively. A fluctuating pattern of sea level change was established in the White Sea after the drainage of proglacial lakes and intrusion of ocean waters at the end of the early Holocene (nearly 8.5-8.2 ka BP). Major periods of sea level rise in the White Sea are dated from the late Boreal-early Atlantic (8.5-7.5 ka BP), late Atlantic (6.5-5.2 ka BP), middle Subboreal (4.5-4 ka BP) and middle Subatlantic (1.8-1.5 ka BP). Fluctuations of relative sea level during the middle and late Holocene were possibly on the order of several meters (from 3 to -2-3 m in the Black Sea and from 5 to -2-3 m in the White Sea). Lower estimates of regressive stages are principally derived from archaeological data on ancient settlements in tectonically submerging deltaic areas and cannot be regarded as reliable.Palaeohydrological analysis does not indicate that intensive (15-25 m or greater) sea level fluctuations were present in the Black Sea or in the White Sea during the middle and late Holocene. Instead, such analysis provides independent evidence to support the argument that significant differences in water level between the Black Sea and the Mediterranean could not be maintained for an extended period of time

Spelologische Charakterisierung und Analyse des Hochschwab-Plateaus, Steiermark, 2004, Plan, L.
The Hochschwab is one of the major karst massifs of the Northern Calcareous Alps (NCA), situated in the north of the Austrian province of Styria and provides freshwater for the city of Vienna. Karstmorphological mapping of 44 km of its plateau brought the discovery of 770 new caves. Together with formerly recorded caves and possible caves detected on aerial photographs a total of 1284, mainly vertical objects are integrated into a GIS. In combination with additional digital datasets, statistical analyses are performed considering the spatial distribution of cave density as well as the dependence on altitude and lithology. Beside this, the most important caves within the study area are characterised. The investigated caves are mainly pits and vertical canyons which developed in the vadose zone. Phreatic cave levels associated with former valley floors, which are common in the NCA, do not exist in the Hochschwab. A few caves of phreatic origin developed above aquitard geological units. The average cave density in the investigation area is 24 objects/km. In glacially strongly overprinted areas it increases to more than 400 caves per km. Remarkable facts of the dependence on lithology are that the limestone of the Dachstein Formation does not show an increased cave density. In contrast, the diverse facies of the limestones of the Wetterstein Formation exhibit major differences.

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