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Enviroscan Ukrainian Institute of Speleology and Karstology


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Community news

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 point of inflection is the point where a curve changes slope [16].?

Checkout all 2699 terms in the KarstBase Glossary of Karst and Cave Terms


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Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
See all featured articles
Featured articles from other Geoscience Journals
Karst environment, Culver D.C.
Mushroom Speleothems: Stromatolites That Formed in the Absence of Phototrophs, Bontognali, Tomaso R.R.; D’Angeli Ilenia M.; Tisato, Nicola; Vasconcelos, Crisogono; Bernasconi, Stefano M.; Gonzales, Esteban R. G.; De Waele, Jo
Calculating flux to predict future cave radon concentrations, Rowberry, Matt; Marti, Xavi; Frontera, Carlos; Van De Wiel, Marco; Briestensky, Milos
Microbial mediation of complex subterranean mineral structures, Tirato, Nicola; Torriano, Stefano F.F;, Monteux, Sylvain; Sauro, Francesco; De Waele, Jo; Lavagna, Maria Luisa; D’Angeli, Ilenia Maria; Chailloux, Daniel; Renda, Michel; Eglinton, Timothy I.; Bontognali, Tomaso Renzo Rezio
Evidence of a plate-wide tectonic pressure pulse provided by extensometric monitoring in the Balkan Mountains (Bulgaria), Briestensky, Milos; Rowberry, Matt; Stemberk, Josef; Stefanov, Petar; Vozar, Jozef; Sebela, Stanka; Petro, Lubomir; Bella, Pavel; Gaal, Ludovit; Ormukov, Cholponbek;
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Your search for removal (Keyword) returned 84 results for the whole karstbase:
Showing 31 to 45 of 84
Gypsum Karst in the Western Ukraine: Hydrochemistry and Solution Rates, 2001,
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Klimchouk A. B. , Aksem S. D.
Gypsum karst in the Western Ukraine underlies a large territory of more than 20,000 km2 and is represented by a range of stages (evolutionary types), from deep-seated through subjacent to entrenched. Correspondingly, hydrogeological settings of karst development, circulation patterns, and chemical characteristics of groundwaters differ substantially between the respective areas. Based on 1,800 analyses, the paper summarises hydrochemistry of the gypsum-hosting Miocene aquifer. Most of the sampling has been performed in conjunction with a regime study of gypsum-solution rates by means of standard tablets. This study included 53 tablet stations representing varying conditions of water-rock interaction, where 644 weight-loss measurements have been made during 1984-1992. The highest rates are characteristic of entrenched karst, although active dissolution there is localised along well-defined sinking streams with short underground courses, rare vertical-percolation paths, and the water table. Lower, but still quite substantial, rates are characteristic for subjacent and deep-seated (confined) karst. However, the overall dissolution removal is higher there, due to higher rates of flow through the gypsum and the larger area of rock/solvent contact. The results are generalised in order to derive the approximate solution rates that characterise major situations and that are suitable for modelling purposes.

Hydrology, Hazards, and Geomorphic Development of Gypsum Karst in the Northern Black Hills, South Dakota and Wyoming, 2001,
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Epstein, J. B.

Dissolution of gypsum and anhydrite in four stratigraphic units in the Black Hills, South Dakota and Wyoming, has resulted in development of sinkholes and has affected formational hydrologic characteristics. Subsidence has caused damage to houses and water and sewage retention sites. Substratal anhydrite dissolution in the Minnelusa Formation (Pennsylvanian and Permian) has produced breccia pipes and pinnacles, a regional collapse breccia, sinkholes, and extensive disruption of bedding. Anhydrite removal in the Minnelusa probably dates back to the early Tertiary when the Black Hills was uplifted and continues today. Evidence of recent collapse includes fresh scarps surrounding shallow depressions, sinkholes more than 60 feet deep, and sediment disruption and contamination in water wells and springs. Proof of sinkhole development to 26,000 years ago includes the Vore Buffalo Jump, near Sundance, WY, and the Mammoth Site in Hot Springs, SD. Several sinkholes in the Spearfish Formation west of Spearfish, SD, which support fish hatcheries and are used for local agricultural water supply, probably originated 500 feet below in the Minnelusa Formation. As the anhydrite dissolution front in the subsurface Minnelusa moves down dip and radially away from the center of the Black Hills uplift, these resurgent springs will dry up and new ones will form as the geomorphology of the Black Hills evolves. Abandoned sinkholes and breccia pipes, preserved in cross section on canyon walls, attest to the former position of the dissolution front. The Spearfish Formation, mostly comprising red shale and siltstone, is generally considered to be a confining layer. However, secondary fracture porosity has developed in the lower Spearfish due to considerable expansion during the hydration of anhydrite to gypsum. Thus, the lower Spearfish yields water to wells and springs making it a respectable aquifer. Processes involved in the formation of gypsum ka 


Geological and geotechnical context of cover collapse and subsidence in mid-continent US clay-mantled karst, 2002,
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Cooley T,
This paper presents a synthesis of geologic and geotechnical concepts to present a unified model of conditions controlling The development of cover-collapse sinkholes and associated ground subsidence. Appropriate engineering response to the hazards associated with collapse and subsidence requires a full understanding of the underlying mechanisms that produce such effects. The geotechnical characteristics of the overlying clay mantle and occurrence of the associated cover-collapse features are not random, but rather are directly tied to the underlying water flow routes and their development through time. The clay mantle and underlying epikarst are two components of a single system, each of the components influencing the other. This paper brings together these two aspects in terms of the author's personal experience and observations as a geologist, geotechnical engineer, hydrogeologist, and caver. A summary of the basic model follows. Much of the clay mantle and pinnacled upper surface of the epikarst form while surface drainage still prevails. At this stage, the karst underdrains are insufficiently developed to transport soils, although some subsidence into cutters occurs because of dissolutional rock removal. Soil arches and macropore flow routes associated with cutters have developed by this stage. As competent deep conduits extend into the area by headward linking, the cutters with the most favorable drains are linked to the conduits first and act as attractors for the development of a tributary, laterally integrated drainage system in the epikarst. Once the most efficient cutter drains become competent to transport soils, the depressed top-of-rock and ground surfaces characteristic of dolines develop. A given doline underdrain is likely to have multiple tributary drains from adjacent cutters, which vary in soil transport competence. Soil stiffness in the clay mantle over the limestone varies as a result of the pattern of stresses imposed as the underlying rock surface is lowered by dissolution and later as soil piping locally removes soils. In the absence of karst, these soils would have developed a laterally uniform, stiff to very stiff consistency. Where soil near the soil-bedrock interface is locally removed, however, the weight of the materials overlying this void is transferred to abutment zones on the pinnacles by soil arches. Local soil loading in the abutment areas of these arches would increase at least on the-order of 50% in the case of an isolated cavity. In some cases, multiple closely spaced cutters whose soil arches have narrow, laterally constrained abutment zones bearing on the intervening pinnacles may produce substantially higher soil abutment stresses. If the clays in the abutment zones do not fail, they would respond to this increase in stress by consolidating: stiffening and decreasing in volume. The cutters spanned by the soil arches accumulate raveled soils that are 'under-consolidated', the soft zones noted between pinnacles by Sowers. A simple integral of stresses analysis makes it obvious, however that no continuous soft zone exists. It is the transfer of load to the pinnacles through the stiffened abutment soils that allows these locally soft areas to exist. Soil stiffness profiles from borings substantiate this pattern. Cover-collapse features develop where soil transport through cutter drains is sufficient to remove the soils from beneath these arched areas. Two types of collapse have been observed: type I collapses have an upward-stoping open void whose rubble pile is removed by transport as fast as it is generated, producing a deep, steep-sided final collapses. In some cases, multiple voids in clusters can form with narrow abutments separating them. Large collapses may involve a progressive failure of several members of a cluster, including intervening pillars. Type 2 features are soil-filled voids limited in their rate of upward growth by the rate of soil removal, have little open void space, and migrate to the ground surface as a column of soft soils, finally producing a shallow depression. The type 2 features have geotechnical significance because of their effect on settlement under imposed loads. A single underdrain system may service both types of features, the behavior of particular voids being dependent on the relative efficiencies of their drains. This behavior can also change with time because backfilling of the underdrains with soil or flushing out of the soil filling can occur with changes in hydrologic or erosional regimes

Nutrient processing capacity of a constructed wetland in western Ireland, 2002,
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Healy M. , Cawley A. M. ,
In Ireland, constructed wetland systems are increasingly being used to perform tertiary treatment on municipal waste effluent from small towns and villages located in areas whose receiving waters are deemed sensitive. The bedrock formation in the west of Ireland is primarily karst limestone and where the overburden-soil cover is very shallow, such waters are highly sensitive to pollution sources, as little or no natural attenuation and/or treatment will occur. Constructed wetland technology has been seen to offer a relatively low-cost alternative to the more conventional tertiary treatment technologies, particularly when dealing with low population numbers in small rural communities. This paper examines the waste treatment performance, in terms of nutrient (P and N) reduction, of a recently constructed surface-flow wetland system at Williamstown, County Galway, Ireland. Performance evaluation is based on more than two years of water quality and hydrological monitoring data. The N and P mass balances for the wetland indicate that the average percentage reduction over the two-year study period is 51% for total N and 13% for total P. The primary treatment process in the wetland system for suspended solids (between 84 and 90% reduction), biological oxygen demand (BOD) (on average, 49% reduction), N, and P is the physical settlement of the particulates. However, the formation of algal bloom during the growing season reduces the efficiency of the total P removal

The Kukaiau Cave, Mauna Kea, Hawaii, Created by Water Erosion: A New Hawaiian Cave Type, 2003,
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Kempe, S. , Werner, M. S.
In 2000 and 2001, two large (each ca. 1000 m long) cave systems have been surveyed on the eastern, heavily eroded, flank of Mauna Kea: The Paauhau Civil Defense Cave and the Kukaiau Cave (at first called ThatCave/ThisCave System). Both caves occur in the Hamakua Volcanics, 200-250 to 65-70 ka old. They are the first substantial caves documented for lavas of Mauna Kea and the first caves on Hawaii showing extensive morphological signs of water erosion. The Paauhau Civil Defense Cave is a lava tube, as attested by the presence of the typical morphological elements of lava tubes, including secondary ceilings, linings, base sheets, stalactites and lava falls. Subsequently, the cave was modified erosionally by a stream which entered upslope and traversed much, but not all, of the cave, leaving waterfalls, waterfall ponds, scallops, gravel, rounded blocks and mud (Kempe et al. 2003). In contrast the Kukaiau Cave a still active stream cave with a vadose and phreatic section - is essentially erosional in origin. This is concluded from the geology of the strata exposed in the cave and from its morphology: At the upper entrance the cave is situated in a thick series of aa and the lower section was created by removing aa and diamict layers, therefore excluding the possibility that the cave developed from a precursor lava tube. Also, in its phreatic section, the cave makes several right angle turns and moves upward through a series of pahoehoe sheets, unlike any lava tube. Furthermore, a base layer can be followed along which the major section of the upper cave has developed. Allophane and halloysite minerals produced by weathering - helped in sealing the primary porosity of this base layer causing a locally perched water table. Water moving along this base layer on a steep hydraulic gradient through the interstices of aa and through small pahoehoe tubes exerted a high pressure on the porous diamict of the lower cave, causing its erosional removal. Our observations of water erosional caves in lavas of Hawaii offer a new perspective on deep-seated water courses in volcanic edifices.

Quartzite dissolution: karst or pseudokarst?, 2003,
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Wray, R. A. L.

A wide range of landforms of great similarity to limestone karst is found on many of the world's quartz sandstones and quartzites. These landforms have often been dismissed as pseudokarst, but recent investigation shows that the dissolutional removal of silica, even quartz, under earth-surface conditions is a critical process in their formation. They must therefore be regarded as true karst features. Recognition of these genetically similar forms on quartzose rocks now demands the worldwide adoption of a less restrictive, process-based, karst definition. Direct evidence for this near-surface dissolutional weathering is not common. Examples of this process are reviewed here, along with further evidence for the dissolution of silica from within the quartz sandstones of the Sydney Basin in temperate south-eastern Australia. Some of the complex processes by which dissolution attacks the rock remain unclear. However the solubility, thermodynamics, fluid throughput and physical removal of detritus are all critical factors in the formation of what can only be termed karst on quartzites and quartz sandstone.


Evaluation of a peat filtration system for treating highway runoff in a karst setting, 2003,
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Zhou W. F. , Beck B. F. , Green T. S. ,
The deleterious character of highway runoff, especially following long periods without precipitation, has been well documented in the literature. It transports hydrocarbons, heavy metals, and other contaminants from highways, contributing to the pollution of surface water and groundwater. Groundwater is particularly vulnerable in karst areas where highway runoff is transferred quickly into subsurface conduit networks through open sinkholes and/or sinking streams. The difficulties in remediating contaminated karst aquifers make it crucial for karst aquifers to receive only uncontaminated water. A peat filtration system was constructed at the I-40/I-640 interchange in eastern Knoxville, Tennessee, USA, to remove highway runoff contaminants prior to being transported into karst aquifers.- Recent field tests indicate that the system can significantly decrease the concentrations of analyzed constituents including PAHs (polyaromatic hydrocarbons), popper, and zinc. However, the removal efficiency depends on the concentration of the contaminants in the runoff. Long-term monitoring is required to determine the true effectiveness of the designed filtration system and its reliability

Fallen arches: Dispelling myths concerning Cambrian and Ordovician paleogeography of the Rocky Mountain region, 2003,
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Myrow Paul M. , Taylor John F. , Miller James F. , Ethington Raymond L. , Ripperdan Robert L. , Allen Joseph,
High-resolution sedimentologic, biostratigraphic, and stable isotope data from numerous measured sections across Colorado reveal a complex architecture for lower Paleozoic strata in the central Cordilleran region. A lack of precise age control in previous studies had resulted in misidentification and miscorrelation of units between separate ranges. Corrections of these errors made possible by our improved data set indicate the following depositional history. The quartz-rich sandstone of the Sawatch Formation was deposited during onlap of the Precambrian erosion surface in the early Late Cambrian. The overlying Dotsero Formation, a regionally extensive carbonate- and shale-rich succession records blanket-like deposition with only minor facies changes across the state. An extremely widespread, meter-scale stromatolite bed, the Clinetop Bed, caps the Dotsero Formation in most areas. However, a latest Cambrian erosional episode removed 9-11 m of the upper Dotsero Formation, including the Clinetop Bed, from just east of the Homestake shear zone in the Sawatch Range eastward to the Mosquito Range. The overlying Manitou Formation differs in character, and thus in member stratigraphy, on the east vs. west sides of the state. These differences were previously interpreted as the result of deposition on either side of a basement high that existed within the Central Colorado Embayment or Colorado 'Sag,' a region of major breaching across the Transcontinental Arch. This paleogeographic reconstruction is shown herein to be an artifact of miscorrelation. Biostratigraphic data show that the northwestern members of the Manitou Formation are older than the members exposed in the southeastern part of the state and that there is little or no overlap in age between the two areas. This circumstance is the result of (1) removal of older Manitou Formation strata in the southeast by an unconformity developed during the Rossodus manitouensis conodont Zone, and (2) erosion of younger Manitou strata in central and western Colorado along Middle Ordovician and Devonian unconformities. Deciphering these complex stratal geometries has led to invalidation of long-held views on western Laurentian paleogeography during the Cambrian and earliest Ordovician, specifically the existence of the Colorado Sag and a northeast-trending high within the sag that controlled depositional patterns on either side. The mid- Rossodus uplift and resultant unconformity eliminated any and all Upper Cambrian and Lower Ordovician deposits in southern Colorado and northern New Mexico, and thus their absence should not be misconstrued as evidence for earlier nondeposition in this region. Lithofacies distribution patterns and isopach maps provide no evidence that highlands of the Transcontinental Arch existed in Colorado prior to the mid-Rossodus age uplift event. In fact, regional reconstructions of earliest Paleozoic paleogeography along the entire length of the purported Transcontinental Arch should be reevaluated with similarly precise biostratigraphic data to reconsider all potential causes for missing strata and to eliminate topographic elements not supported by multiple stratigraphic techniques. This study illustrates how seriously paleogeographic reconstructions can be biased by the presumption that missing strata represent periods of nondeposition rather than subsequent episodes of erosion, particularly in thin cratonic successions where stratigraphic gaps are common and often inconspicuous

The Sahara-East Mediterranean dust and climate connection revealed by strontium and uranium isotopes in a Jerusalem speleothem, 2004,
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Frumkin A, Stein M,
This paper explores the potential of Sr and U isotope systems in speleothems as tracers of eolian dust transport and hydrological conditions. The study focuses on a speleothem from Jerusalem spanning the past 220 kyr. This speleothem provides a precisely dated record of dust flux from the Sahara to the East Mediterranean. Enhanced dust flux and Terra Rossa soil development are reflected by elevated 87Sr/86Sr ratios in the speleothem (0.7082-0.7086), while lower 87Sr/86Sr ratios (~0.7078) indicate higher contribution of the local bedrock due to low dust flux and low soil accumulation. The strontium isotope system in the speleothem is a robust monitor of the Sahara monsoon-modulated climate, since dust uptake is related to development or reduction in vegetation cover of Sahara soil. The [234U/238U] activity ratios in the speleothem range between 1.12 and 1.0. The high activity values may indicate selective removal of 234U from the soil while the low values converge to the bedrock. The migration of 234U to the cave reflects mainly the regional hydrological conditions that are modulated by the North Atlantic-Mediterranean climate system. Thus, the speleothem provides a combined record of the monsoon-North Atlantic climatic systems. Long-term stability in glacial 87Sr/86Sr ratios (0.70830.0001 over the past 220 kyr) suggests an overall similarity in eolian dust sources, and uniformity in the synoptic conditions that dominate the dust storm tracks during glacial periods

Origin of the salt valleys in the Canyonlands section of the Colorado Plateau - Evaporite-dissolution collapse versus tectonic subsidence, 2004,
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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

Depositional and post-depositional history of warm stage deposits at Knocknacran, Co. Monaghan, Ireland: implications for preservation of Irish last interglacial deposits, 2004,
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Vaughan A. P. M. , Dowling L. A. , Mitchell F. J. G. , Lauritzen S. E. , Mccabe A. M. , Coxon P. ,
Organic-rich deposits, uncovered during overburden removal from mantled gypsum karst at Knocknacran opencast gypsum mine, Co. Monaghan, are the best candidate to date for a last interglacial record in Ireland. The two till and organic-rich deposits (preserved at different quarry elevations) were emplaced on to a Tertiary dolerite surface during high-energy flood events and subsequently folded and faulted by movement towards sinkholes in underlying gypsum. Uranium-thorium disequilibrium dating suggests that the organic-rich deposits in the upper section were hydrologically isolated at ca. 41 ka and those in the lower section at ca. 86 ka. Interpretation of the pollen content, although tentative because of the depositional and post-depositional history of the material, suggests that the organic material originated in a warm stage possibly warmer than the post-Eemian interstadials. The unusual setting of preservation may indicate that in situ, last interglacial deposits have generally been removed by erosion in Ireland.

The Sahara - East Mediterranean dust and climate connection revealed by strontium and uranium isotopes in a Jerusalem speleothem, 2004,
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Frumkin, A. , And Stein, M.
This paper explores the potential of Sr and U isotope systems in speleothems as tracers of eolian dust transport and hydrological conditions. The study focuses on a speleothem from Jerusalem spanning the past 220 kyr. This speleothem provides a precisely dated record of dust flux from the Sahara to the East Mediterranean. Enhanced dust flux and Terra Rossa soil development is reflected by elevated 87Sr/86Sr ratios in the speleothem (0.7082-6), while lower 87Sr/86Sr ratios (~0.7078) indicate higher contribution of the local bedrock due to low dust flux and low soil accumulation. The strontium isotope system in the speleothem is a robust monitor of the Sahara monsoon-modulated climate, since dust uptake is related to development or reduction in vegetation cover of Sahara soil. The [234U/238U] activity ratios in the speleothem range between 1.12 and 1.0. The high activity values may indicate selective removal of 234U from the soil while the low values converge to the bedrock. The migration of 234U to the cave reflects mainly the regional hydrological conditions that are modulated by the North Atlantic-Mediterranean climate system. Thus, the speleothem provides a combined record of the Monsoon - North Atlantic climatic systems. Long-term stability in glacial 87Sr/86Sr ratios (0.70831 over the past 220 kyr) suggests an overall similarity in eolian dust-sources, and uniformity in the synoptic conditions that dominate the dust storm tracks during glacial periods.

Karstification of the aquifer discovered during the construction of the expressway between Klanec and Črni Kal, Classical Karst, 2004,
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Knez Martin, Slabe Tadej, Š, Ebela Stanka

Sixty-seven caves were opened during the earth removal and the excavation of the tunnel on the 6.5 km route section of the expressway between Klanec and Črni Kal. By their number, old caves predominated. Two - thirds of these caves were filled with deposits. The caves investigated contributed to our knowledge of the development of this part of the karst. The more than 450 m - long cave system of caves which we are trying to preserve was opened in the tunnel at Kastelec near the Škrklovica cave. Below the road, the passages of this system are connected with concrete pipes, leading from the roadside.


Hydrochemistry and solution rates in gypsum karst: case study from the Western Ukraine, 2005,
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Klimchouk A. B. , Aksem S. D. ,
The gypsum karst in the Western Ukraine spreads through a large territory covering more than 20,000 km(2) and is represented by a range of stages (evolutionary types), from deep-seated through subjacent to entrenched. Correspondingly, hydrogeological settings of karst development, circulation patterns and chemical characteristics of groundwaters differ substantially between the respective areas. Based on 1,800 analyses, this paper summarises hydrochemistry of the gypsum-hosting Miocene aquifer. The majority of sampling has been performed in conjunction with a study regime of gypsum solution rates by means of standard tablets. In this study, which included 53 tablet stations representing varying conditions of water-rock interaction, 644 weight-loss measurements were made over the period 1984-1992. The highest rates are characteristic of entrenched karst although active dissolution is localised along well-defined sinking streams with short underground courses, rare vertical percolation paths and the water table. Lower but still quite substantial rates are characteristic of subjacent and deep-seated (confined) karst. However, the overall dissolution removal is greater due to higher flow through the gypsum and the larger area of rock-solvent contact. The results are generalised in order to derive the approximate solution rates characterising major situations and to be suitable for modeling purposes

Weathering, geomorphic work, and karst landscape evolution in the Cave City groundwater basin, Mammoth Cave, Kentucky, 2005,
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Groves C. , Meiman J. ,
Following the pioneering work of Wolman and Miller [Wolman, M.G., Miller, J.P., 1960. Magnitude and frequency of forces in geomorphic processes. J. Geol., 68, 54-74.] in evaluation of geomorphic work and the frequencies and magnitudes of forces that drive it, a large number of quantitative studies have focused on the evolution of fluvial systems and transport of elastic sediment. Less attention has been given to understanding frequencies and magnitudes of processes in rock weathering, including investigation of rates at which solutes are removed from landscapes under various flow distributions as an analog to Wolman and Miller's [Wolman, M.G., Miller, J.P., 1960. Magnitude and frequency of forces in geomorphic processes. J. Geol., 68, 54-74.] concept of geomorphic work. In this work, we use I year of high-resolution flow and chemical data to examine the work done in landscape evolution within and at the outlet of Kentucky's Cave City Basin, a well-developed karst landscape/aquifer system that drains about 25 km(2). We consider both removal of solutes contributing to landscape denudation based on calcium mass flux as well as predicted dissolution rates of the conduit walls at the outlet of this basin based on limestone dissolution kinetics. Intense, short-duration events dominate. Storms that filled the Logsdon River conduit occurred < 5% of the year but were responsible for 38% of the dissolved load leaving the system and from 63% to 100% of conduit growth for various scenarios of sediment influence. Landscape denudation is a linear function of the amount of water moving through the system, but conduit growth rates, and thus rates of recharge area evolution from fluvial to karst surface landscapes, depend both on the amount of water available and the distribution of precipitation. © 2004 Published by Elsevier B.V

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