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Enviroscan Ukrainian Institute of Speleology and Karstology


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Speleology in Kazakhstan

Shakalov on 04 Jul, 2018
Hello everyone!   I pleased to invite you to the official site of Central Asian Karstic-Speleological commission ("Kaspeko")   There, we regularly publish reports about our expeditions, articles and reports on speleotopics, lecture course for instructors, photos etc. ...

New publications on hypogene speleogenesis

Klimchouk on 26 Mar, 2012
Dear Colleagues, This is to draw your attention to several recent publications added to KarstBase, relevant to hypogenic karst/speleogenesis: Corrosion of limestone tablets in sulfidic ground-water: measurements and speleogenetic implications Galdenzi,

The deepest terrestrial animal

Klimchouk on 23 Feb, 2012
A recent publication of Spanish researchers describes the biology of Krubera Cave, including the deepest terrestrial animal ever found: Jordana, Rafael; Baquero, Enrique; Reboleira, Sofía and Sendra, Alberto. ...

Caves - landscapes without light

akop on 05 Feb, 2012
Exhibition dedicated to caves is taking place in the Vienna Natural History Museum   The exhibition at the Natural History Museum presents the surprising variety of caves and cave formations such as stalactites and various crystals. ...

Did you know?

That floe calcite is very thin film of pure calcium carbonate floating on the surface of a subterranean pool of very calm water [10].?

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.
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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 evaporites (Keyword) returned 133 results for the whole karstbase:
Showing 121 to 133 of 133
Occurrence and morphology of crayback-like stalagmites in the Painted Cave of Niah (Sarawak, Malaysia), 2012,
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Dodgewan Dominique, Deng Angela Hui Min, Abbas Mohammad Fadhil

The Painted Cave is a subhorizontal relict tunnel passage which runs through a small karst tower, approximately 30m above the surrounding alluvial plain and adjacent to other large karst towers in Niah National Park (Sarawak, Malaysia). Lundberg and McFarlane (2011) described the occurrence, morphology and mode of formation of a crayback stalagmite close to the north entrance of the cave. The presence of numerous other crayback-like stalagmites in three zones of the same cave is reported here. Their elongated humped-back morphology indicates formation influenced by cave wind. The axial orientations of the crayback-like stalagmites are similar in each of the three cave zones, but differ between the zones. Many of the stalagmite features resemble those of crayback stalagmites, suggesting that cyanobacteria may also have played a role in their formation. The Painted Cave has large entrances at both ends. The natural light levels within the cave are sufficient for cyanobacterial growth and cave wind is noticeable. A suite of stalagmite morphologies ranging from forms that are wind influenced but abiotic, to forms that are also moderately to strongly influenced by cyanobacteria is suggested.


Differences in karst processes between northern and southern China, 2012,
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Hao Y. , Cao B. , Zhang P. , Wang Q. , Li Z. , Yeh T. C. J.

The east–west trending Tsinling Mountains in central China were uplifted at the end of the Middle Jurassic [176–161 million years ago (Ma)] in Yanshanian, thus effectively and geographically defining the northern climate as cold and dry, and the southern climate as warm and humid. Influenced by paleoenvironmental variation, the karst process shows differences between northern and southern China. Using the systems approach, the authors integrated the geologic history, climate, and hydrological conditions to analyze the causes of the karst differences in northern and southern China, as well as in the Tibetan Plateau. Carbonate rock deposition began in the Mesoproterozoic Era (1,600–1,000 Ma) in north China, and in the Sinian Sub-Era (825–570 Ma) in south China. In north China, the rock formation ended in the Mid-Ordovician (466 Ma), while in South China the deposition continued to the Triassic (250–200 Ma). Tibetan Plateau was deposited in the Late Permian (257–250 Ma). The different depositional environment caused different lithologies: the limestones are largely micritic in the north, but are massive and sparry in the south. The modern karst features were formed mainly in the Tertiary (53–2.6 Ma) and the Quaternary. In the Quaternary, the Tibetan Plateau arose sharply, which formed the monsoon system of East Asia, and loess started to deposit in north China, which partly delayed or prevented karstification in north China, and differentiated the karst features from those in south China. Thus, the karst process in north China is mainly hypogene, while the south is epigene in the Quaternary.


Differences in karst processes between northern and southern China, 2012,
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Hao Y. , Cao B. , Zhang P. , Wang Q. , Li Z. , Jim Yeh T. C.

The east–west trending Tsinling Mountains in central China were uplifted at the end of the Middle Jurassic [176–161 million years ago (Ma)] in Yanshanian, thus effectively and geographically defining the northern climate as cold and dry, and the southern climate as warm and humid. Influenced by paleoenvironmental variation, the karst process shows differences between northern and southern China. Using the systems approach, the authors integrated the geologic history, climate, and hydrological conditions to analyze the causes of the karst differences in northern and southern China, as well as in the Tibetan Plateau. Carbonate rock deposition began in the Mesoproterozoic Era (1,600–1,000 Ma) in north China, and in the Sinian Sub-Era (825–570 Ma) in south China. In north China, the rock formation ended in the Mid-Ordovician (466 Ma), while in South China the deposition continued to the Triassic (250–200 Ma). Tibetan Plateau was deposited in the Late Permian (257–250 Ma). The different depositional environment caused different lithologies: the limestones are largely micritic in the north, but are massive and sparry in the south. The modern karst features were formed mainly in the Tertiary (53–2.6 Ma) and the Quaternary. In the Quaternary, the Tibetan Plateau arose sharply, which formed the monsoon system of East Asia, and loess started to deposit in north China, which partly delayed or prevented karstification in north China, and differentiated the karst features from those in south China. Thus, the karst process in north China is mainly hypogene, while the south is epigene in the Quaternary.


Hypogene Speleogenesis, 2013,
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Klimchouk, A. B.

Recognition of the wide occurrence, significance, and specific characteristics of hypogene speleogenesis during last twodecades signifies a major paradigm shift in karst science, previously overwhelmingly dominated by epigene concepts and models. Hypogene karst is one of the fundamental categories of karst, at least of equal importance with more familiar epigenic karst. Hypogene and epigenic karst systems are regularly associated with different types, patterns, and segments off low systems, which are characterized by distinct hydrokinetic, chemical, and thermal conditions. Hypogene speleogenesis is the formation of solution-enlarged permeability structures by water that recharges thecavernous zone from below, independent of recharge from the overlying or immediately adjacent surface. It develops mainly in leaky confined conditions, although it may continue through unconfined ones. Hydraulic communication along cross-formational flow paths, across lithological boundaries, different porosity systems, and flow regimes allows deeper ground waters in regional or intermediate flow systems to interact with shallower and more local systems, permittinga variety of dissolution mechanisms to operate. A specific hydrogeologic mechanism acting in hypogenic transverse speleogenesis (restricted input/output) suppresses the positive flow-dissolution feedback and speleogenetic competition seen in the epigenic development. Hypogenic caves occur in different soluble rocks in a wide range of geological and tectonic settings, basinal throughorogenic. Overall patterns of cave systems are strongly guided by the spatial distribution of the initial (prespeleogenetic) permeability features and hydrostratigraphic barriers and interfaces within the soluble and adjacent units, by the mode of water input to, and output from, cave-forming zones and by the overall recharge–discharge configuration in the multiple aquifer system. Because of their transverse nature, hypogene caves have a clustered distribution in plan view, althoughinitial clusters may merge laterally across considerable areas. Hypogene caves display remarkable similarity in their pattern sand mesomorphology, strongly suggesting that the type of flow system is the primary control. The rapidly evolving understanding of hypogene speleogenesis has broad implications for many applied fields such asprospecting and characterization of hydrocarbon reservoirs, groundwater management, geological engineering, and mineral resources industries


Evolution of Intrastratal Karst and Caves in Gypsum, 2013,
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Klimchouk, A. B.

The term ‘intrastratal karst’ denotes a series of evolutionary karst types corresponding to successive stages of karst developmentin a soluble rock while it moves back to exposure after being buried by younger strata. The major boundaryconditions, the overall circulation pattern, and extrinsic factors and intrinsic mechanisms of karst development appear tochange considerably between the stages, resulting in characteristic styles of cave development and surface karst morphology,particularly distinct in case of gypsum karst.As gypsum is much more soluble than carbonates, it does not survive long in outcrops beyond arid areas. Wheregypsum is exposed to the surface with no substantial karstification formed during various stages of reburial, the developmentof epigene solution porosity in this rock is hindered due to the fast dissolution, being limited to flow paths in whichthe breakthrough conditions can be attained quickly. However, karst processes in gypsum develop extensively in intrastratalkarst settings, with inheritance from the deep-seated stage through the denuded one. Karstification may commence in anystage of intrastratal development, and during the next successive stage, the process, although in changed conditions, will beaffected significantly by the preformed solution porosity. Speleogenesis in deep-seated gypsum karst is exclusively hypogene.In subjacent karst, both hypogene and epigene speleogenesis may operate depending on the locally prevailing flowregime, but hypogene speleogenesis still dominates. In entrenched and denuded karst types, speleogenesis is overwhelminglyepigenic, but it is greatly facilitated by the presence of solution porosity inherited from the previous stages.Diverse and expressive karst landforms related to subsurface conduits evolve through different stages of the intrastratal karstdevelopment.The subsidence hazard in regions underlain by gypsum differs substantially between the karst types, so that one canobtain a kind of integrated general hazard assessment by classifying a given individual karst according to its evolution state.In general, various types of intrastratal karst, subjacent karst in particular, are the most potent in generating subsidence problems, whereas exposed karst types, particularly open karst, are the least prone to subsidence


Bench-scale models of dye breakthrough curves, 2013,
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Anger Cale T. , Alexander Jr. E. Calvin

Fluorescent dye tracer breakthrough curves (TBCs) obtained from quantitative traces in karst flow systems record multiple processes, including advection, dispersion, diffusion, mixing, adsorption, and chemical reaction. In this study, TBCs were recorded from small, bench-scale physical models in an attempt to isolate, understand, and quantify some of these processes under full-pipe flow conditions. Dye traces were conducted through a suite of geometries constructed out of Pyrex glass. These geometries consisted of (1) linear conduits, of varying length and diameter, (2) single and dual mixing chambers, and (3) a single chamber with an immobile region. Each glass system was connected to a constant flow apparatus. Dye was then injected with a syringe, allowed to flow through the system, and be naturally or artificially mixed in the process. Solute breakthrough was recorded in a scanning spectrofluorophotometer and the resulting TBC was analyzed. Independent variables examined in each of the three settings were discharge (Q) and dye concentration (Co). Artificial mixing rates (RM), induced by magnetic stirrers in settings (2) and (3), were also considered. Initial runs varied Q from 0.75 to 1.25 mL/s, with constant RM ranging from 0 to 360 revolutions per minute (rpm). Preliminary data yield realistic-looking breakthrough curves with steeply rising leading edges, a peak, and an asymmetric, exponential tail. Analysis of laboratory variables with respect to hydraulic parameters extracted from each TBC suggests that discharge and mixing rate alone can differentiate conduit complexity at the laboratory scale.

 


Differentiated characterization of karst aquifers: some contributions, 2013,
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Geyer T. , Birk S. , Reimann T. , Dorfliger N. , Sauter M.

Because of the small radius of investigation of hydrogeological standard testing methods, the characterization of karst aquifers is still a challenge. The development of a karst conduit system introduces an element of large contrast in hydraulic conductivity in the hydraulic parameter field of a karst aquifer. It leads to complex flow patterns and transport phenomena that differ significantly from those observed in porous and fissured media. While on a local, i.e., borehole scale, the fissured matrix of karst aquifers can be regarded as a continuum, on a regional, i.e., catchment scale, the drainage of the aquifer system is controlled by the conduit system, which may have a highly anisotropic geometry. Therefore, characterization of karst aquifers requires a differentiated approach by the combination of various hydrogeological field methods or the application of large-scale tests, which cover the scale of dominant aquifer heterogeneities. Existing numerical modeling approaches can be applied for integral data interpretation on catchment scale.


Comparison of discharge, chloride, temperature, uranine, dD, and suspended sediment responses from a multiple tracer test in karst, 2013,
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Luhmann A. J. , Covington M. D. , Alexander S. C. , Chai S. Y. , Schwartz B. F. , Groten J. T. , Alexander Jr. E. C.

A controlled recharge event with multiple tracers was conducted on August 30, 2010. A pool adjacent to a sinkhole was filled with approximately 13,000 L of water. The water was heated, and salt, deuterium oxide, and uranine were added. The pool was then emptied into the sinkhole, and data were collected at Freiheit Spring approximately 95 m north of the sinkhole to monitor changes in discharge, temperature, conductivity/chloride, dD, uranine, and suspended sediment. This combined trace demonstrated the feasibility and utility of conducting superimposed physical, chemical, and isotopic traces. Flow peaked first at the spring and was followed by a suspended sediment peak; then essentially identical uranine, chloride, and dD peaks; and finally a temperature peak. The initial increase in flow at the spring recorded the time at which the water reached a submerged conduit, sending a pressure pulse to the spring at the speed of sound. The initial increase in uranine, chloride, and dD at the spring recorded the arrival of the recharge water. The initial change in temperature and its peak occurred later than the same parameters in the uranine, chloride, and dD breakthrough curves. As water flowed along this flow path, water temperature interacted with the aquifer, producing a delayed, damped thermal peak at the spring. The combination of conservative and nonconservative tracers illustrates unique pressure, advective, and interactive processes.


The Grosmont: the worlds largest unconventional oil reservoir hosted in polyphase-polygenetic karst, 2013,
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Machel Hans G. , Borrero Mary Luz, Dembicki Eugene, Huebscher Harald4

The Upper Devonian Grosmont platform in Alberta, Canada, is the world’s largest heavy oil reservoir hosted in carbonates, with 400-500 billion barrels of IOIP at an average depth of about 250 – 400 m. Advanced thermal recovery technologies, such as SAGD and electrical in-situ retorting, much higher world market prices for oil and certain political pressures have led to a flurry of activity in the Grosmont since 2006.
The sedimentary stratigraphy of the Grosmont reservoir consists of six stacked car-bonate units interbedded with marls and some evaporites. The latter two originally acted as aquitards during diagenesis but are breached or missing in parts of the area today. Dolomitization by density-driven reflux was the first pervasive diagenetic pro-cess. A dense fracture network was created in three or four phases. Most fractures probably originated from collapse following subsurface salt dissolution and/or from Laramide tectonics far to the west, whereby pulsed crustal loading in the fold-and-thrust belt created a dynamic forebulge in the Grosmont region via multiple pulses of basin-wide crustal flexing, each followed by relaxation. The fracture network probably was reactivated and/or expanded by glacial loading and post-glacial isostatic rebound in the Pleistocene and Holocene, respectively.
The region experienced three or four prolonged periods of epigene karstification, alt-hough there is tangible evidence for only two of them in the Grosmont platform. The first of these episodes was a ‘warm epigene karstification’ during the Jurassic - Creta-ceous, and the second was/is a ‘cold epigene karstification’ that started sometime in the Cenozoic and is continuing to this day. In addition, there is circumstantial evidence for hypogene ‘karstification’ (= dissolution) throughout much of the geologic history of the Grosmont since the Late Devonian. Karstification was accompanied and/or by fol-lowed by extensive hydrocarbon biodegradation.


Investigating Groundwater Flow Between Edwards and Trinity Aquifers in Central Texas, 2013,
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Wong C. I. , Kromann J. S. , Hunt B. B. , Smith B. A. , Banner J. L.

Understanding the nature of communication between aquifers can be challenging when using traditional physical and geochemical groundwater sampling approaches. This study uses two multiport wells completed within Edwards and Trinity aquifers in central Texas to determine the degree of groundwater inter-flow between adjacent aquifers. Potentiometric surfaces, hydraulic conductivities, and groundwater major ion concentrations and Sr isotope values were measured from multiple zones within three hydrostratigraphic units (Edwards and Upper and Middle Trinity aquifers). Physical and geochemical data from the multiport wells were combined with historical measurements of groundwater levels and geochemical compositions from the region to characterize groundwater flow and identify controls on the geochemical compositions of the Edwards and Trinity aquifers. Our results suggest that vertical groundwater flow between Edwards and Middle Trinity aquifers is likely limited by low permeability, evaporite-rich units within the Upper and Middle Trinity. Potentiometric surface levels in both aquifers vary with changes in wet vs. dry conditions, indicating that recharge to both aquifers occurs through distinct recharge areas. Geochemical compositions in the Edwards, Upper, and Middle Trinity aquifers are distinct and likely reflect groundwater interaction with different lithologies (e.g., carbonates, evaporites, and siliceous sediments) as opposed to mixing of groundwater between the aquifers. These results have implications for the management of these aquifers as they indicate that, under current conditions, pumping of either aquifer will likely not induce vertical cross-formational flow between the aquifers. Inter-flow between the Trinity and the Edwards aquifers, however, should be reevaluated as pumping patterns and hydrogeologic conditions change.


EVAPORITE KARST AND HYDROGEOLOGY OF THE CASTILE FORMATION: CULBERSON COUNTY, TEXAS AND EDDY COUNTY, NEW MEXICO, 2013,
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Stafford, K. W.

Karst development in Permian Castile evaporites has resulted in complex speleogenetic evolution with multiple phases of diagenetic overprinting. More than 10,000 surficial features, primarily sinkholes, occur throughout Culberson County, Texas, and Eddy County, New Mexico, based on GIS-analyses where laminated Castile sulfates crop out. Cave development is largely the result of hypogene processes, where ascending fluids from the underlying Bell Canyon Formation migrate near vertically through the Castile Formation, creating caves up to 100 meters deep and over 500 meters long, which have been breached through a combination of collapse and surface denudation. Numerous small and laterally limited epigene features occur throughout the region, as well as the anomalously large Parks Ranch Cave System with more than 6.5 kilometers of cave development and multiple large, incised, sinkhole entrances. Hypogene caves exhibit varying degrees of epigenic overprinting as a result of surficial breaching.

Water resources in the Castile Formation are directly related to karst development with extremely heterogeneous flow networks. Most springs in the region discharge sulfate-rich waters, contain high levels of hydrogen sulfide, and support sulfate-reducing bacterial colonies. Isolated stream passages in northern Culberson County provide locally significant water resources that do not exhibit elevated hydrogen sulfide concentrations. Local water tables vary greatly over the region and few caves access base-level conditions. Upward migration of hydrocarbons complicates regional hydrology and diagenesis, resulting in extensive evaporite calcitization, which greatly modifies both fluid / rock interaction and permeability structures.


VARIATIONS IN EVAPORITE KARST IN THE HOLBROOK BASIN, ARIZONA, 2013,
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Neal J. T. , Johnson K. S. , Lindberg P.

At least six distinct forms of evaporite karst occur in the Holbrook Basin•depending considerably on overburden and/or bedrock type. Early Permian evaporites in the 300-m-thick Corduroy Member of the Schnebly Hill Formation include halite, sylvite, and anhydrite at depths of 215-250 m. Karst features result from collapse of overlying Permian and Triassic strata into underlying salt-dissolution cavities. Evaporite karst occurs primarily along the 100+ km-long dissolution front on the southwestern edge of the basin, and is characterized by numerous sinkholes and depressions generally coincident with the axis of the Holbrook Anticline•in reality a dissolution-collapse monocline. “The Sinks” comprise ~ 300 individual sinks up to 200 m across and 50 m deep, the main karst features along the dissolution front. Westerly along the dissolution front, fewer discrete sinkholes occur, and several breccia pipes are believed to be forming. Numerous pull-apart fissures, graben-sinks, sinkholes, and broad collapse depressions also occur.A newly recognized subsidence/collapse area of some 16 km2 occurs in the western part of the basin, northward from the extension of the Holbrook “anticline.” The Chimney Canyon area is some 12 km east of McCauley Sinks, a postulated breccia pipe exemplified in, and possibly manifested in at least four other closed depressions. Interferometric Synthetic Aperture Radar (InSAR) data of one depression shows active subsidence of ~4 cm/yr.Karst formation is ongoing, as shown by repeated drainage of Dry and Twin Lakes into newly opened fissures and sinkholes. These two playa lakes were enlarged and modified in recent years into evaporation 2impoundments for effluent discharge from a nearby pulp mill. Four major drainage events occurred within these playa reservoirs during the past 45 years, collectively losing more than 1.23 x107 m3 (10,000 acre-feet) of water and playa sediment. Drainage occurs through piping into bedrock joints in Triassic Moenkopi Formation (sandstone) in the bottom and along the margins of these playas. Effluent discharge has been discontinued into these playas, although recurring precipitation can fill the basins.


Origin of the palaeokarst in Miocene evaporites on the SW periphery of the Eastern European Platform in the light of palynological studies – a case study of the Zoloushka Cave, Bukovina, Western Ukraine, 2014,
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The Zoloushka Cave belongs to a group of the largest gypsum caves in Western Ukraine (Bukovina region), developed in the middle Miocene (upper Badenian) evaporite series (Tyras Formation) on the SW periphery of the East European Platform. It is developed in the lower part of the evaporite series composed of gypsum, which is covered by a carbonate layer (Ratyn Limestone). The uneven upper surface of the gypsum at the contact with the limestone, the frequent occurrence of palaeokarst forms, and the presence of karstified fissures filled with allochthonous material indicate a sedimentation break between the gypsum and the overlying limestone. To support this thesis and to add new data on the age and palaeoenvironmental conditions of palaeokarst formation in the Bukovina region, palynological studies were carried out on material from the Zoloushka Cave. Palynofacies, sporomorphs and dinoflagellate cysts were studied. In total, over 70 sporomorph taxa and over 25 dinoflagellate cyst taxa have been identified in four samples collected from the filling of the palaeokarstic forms in the cave. The results of the analysis of sporomorphs and dinoflagellate cysts point to the formation of the palaeokarst during the sedimentation break that took place at the end of the late Badenian evaporitic cycle in the Western Ukraine region. The subsequent marine transgression led to the filling of the karst forms in gypsum with chemogenic carbonate material, precipitated from marine water (draperies) and with fine-grained, clastic material (pockets and fissures).


     

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