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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 hydroscopic coefficient is the amount of absorbed water on the surface of soil particles in an atmosphere of 50% relative humidity at 25řc [16].?

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

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What is Karstbase?



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KarstBase a bibliography database in karst and cave science.

Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
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;
See all featured articles from other geoscience journals

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Your search for exposure (Keyword) returned 139 results for the whole karstbase:
Showing 31 to 45 of 139
Radon exposure during underground trips: A set of guidelines for cave and mine exploration in Britain, 1996,
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Friend C. R. L. (ed. )

The influence of climatic change on exposure surface development: a case study from the Late Dinantian of England and Wales, 1996,
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Vanstone Simon,
Exposure surfaces represent an integral part of Asbian-Brigantian cyclothemic platform carbonates in England and Wales. These are characterized by the association of clay palaeosols, calcrete and palaeokarst and in most instances would appear to have been polygenetic. Alternating calcrete-karst stratigraphies associated with individual exposure surfaces indicate that the climate changed from semi-arid to humid to semi-arid conditions during each sea-level fall/rise cycle. Lowstand intervals were humid and resulted in karstification of the cyclothem-top sediments and the formation of a mineral soil. In contrast, regressive/transgressive phases were semi-arid and resulted in calcretization of the emergent platform carbonates. The influence that climatic cyclicity had upon exposure surface development was modulated by variations in platform bathymetry, subsidence and spatial climatic variation, and platforms exhibit their own individual record of what was essentially an idealized sequence of events. As with the sea-level oscillations responsible for cyclothemic sedimentation, the climatic cyclicity is thought to be the product of orbital forcing and probably reflects either eccentricity-driven shifts in the locus of monsoonal precipitation, or precession-driven variations in monsoonal intensity. If precessional in origin, exposure surface development represents a single minimum to minimum excursion, some 20 ka in duration, whereas if eccentricity-driven this may have been appreciably longer. Nevertheless, the immature nature of the exposure surfaces suggests that emergence was probably only of the order of a few tens of thousands of years

Vadose weathering of sulfides and limestone cave development-Evidence from eastern Australia., 1996,
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Osborne R. A. L.

Many significant limestone caves in eastern Australia (particularly New South Wales, Tasmania) are associated with sulfide deposits and other ore bodies. These deposits have a variety of origins (hydrothermal, paleokarst, volcaniclastic). The sulfides weather on exposure to oxygen - rich vadose seepage water, lowering the water pH and releasing sulfate and magnesium which can lead to the deposition of gypsum and aragonite speleothems. Removal of weathered ores and ore - bearing paleokarst sediments in the vadose zone is, in places, an important mechanism for the formation of large caverns.

Determining the Exposure Age of a Karst Landscape, 1996,
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Frumkin A,
An extensive salt karst system has developed in Mount Sedom salt diapir, Israel, during the Holocene. Multilevel vadose caves were14C dated using wood fragments embedded in alluvial deposits. The oldest date of each cave is used to constrain the age of the salt exposure. The upper portion of the southeastern escarpment was the first to rise above base level ~7100 yr B.P. Caves in the surrounding area indicate gradual landscape exposure around this initial karstified area between 7000 and 4000 yr B.P. The northern part of the mountain experienced a similar exposure history, lagging some 3000 yr after the southern part. This lag may be attributed to the narrow width of the diapir in the north, which increases viscous drag at the borders of the rising diapir

Symposium Abstract: Exposure to Radon in Gilfield Mine [North Yorkshire], 1997,
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Barkerread G. R. , Farnfield R. A.

The Lower Triassic Montney Formation, west-central Alberta, 1997,
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Davies Gr, Moslow Tf, Sherwin Md,
The Lower Triassic Montney Formation was deposited in a west-facing, arcuate extensional basin, designated the Peace River Basin, on the northwestern margin of the Supercontinent Pangea, centred at about 30 degrees N paleolatitude. At least seasonally arid climatic conditions, dominance of northeast trade winds, minimum fluvial influx, offshore coastal upwelling, and north to south longshore sediment transport affected Montney sedimentation. Paleostructure, particularly highs over underlying Upper Devonian Leduc reefs and lows associated with graben trends in the Peace River area, strongly influenced Montney depositional and downslope mass-wasting processes. A wide range of depositional environments in the Montney is recorded by facies ranging from mid to upper shoreface sandstones, to middle and lower shoreface HCS sandstones and coarse siltstones, to finely laminated lower shoreface sand and offshore siltstones. and to turbidites. Dolomitized coquinal facies occur at seven stratigraphic horizons in the Montney. Some coquinas are capped by karst breccias and coarse-grained aeolian deflation lag sand residues indicating subaerial exposure. The Montney has been divided into three informal members that have been dated by palynology and compared with global Early Triassic sequences. The subdivisions are: the Lower member, of Griesbachian to Dienerian age, correlated with a third-order cycle; the Coquinal Dolomite Middle member, of mixed Dienerian and Smithian ages; and the Upper member, of Smithian to Spathian age, correlative with two, shorter-duration third-order cycles. A forced regressive wedge systems tract model is adopted for deposition of the Coquinal Dolomite Middle member and for turbidites in the Valhalla-La Glace area of west-central Alberta. With this model, coquinas and turbidites accumulated during falling base level to lowstand, with a basal surface of forced regression at the base of the coquina and a sequence boundary at the top of the coquinal member. This is supported by the evidence for subaerial exposure and maximum lowstand at the top of the coquina. Very limited grain size distribution in the Montney, dominantly siltstone to very fine-grained sandstone, but often very well sorted, is interpreted to reflect an aeolian influence on sediment source and transport, High detrital feldspar and detrital dolomite in the Montney are consistent with (but not proof of) aeolian source from an arid interior, as is high detrital mica content in finer size grades. Extensive and often pervasive dolomitization, and early anhydrite cementation within the Montney, are also consistent with an arid climatic imprint. As new exploratory drilling continues to reveal the wide range of facies in the Montney, it adds to both the complexity and potential of this relatively unique formation in western Canada

Principal features of evaporite karst in Canada, 1997,
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Ford Dc,
Outcrops of sulfate arid mixed sulfate-carbonate rocks are common everywhere in Canada outside of the Shield province. Interstratal salt deposits are abundant in the interior lowlands. Types of karst that occur are determined chiefly by relations between (i) formation thickness and purity, (ii) regional topography and hydraulic gradient (iii) effects of receding Wisconsinan and earlier glaciers, and (iv) extent of modern permafrost. Exposures of bare karst on thick, pure sulfate formations are comparatively rare. Two principal landform types found on them are: (1) high-density polygonal karst (micro-sinkhole densities of thousands per km(2)); where hydraulic gradients are high and tills are thin; (2) hills and ridges of blocks uplifted and fractured by hydration (anhydrite) tectonics at paleo-icefront positions where hydraulic gradients are low. Deeply till-mantled karst dominated by collapse and suffosion sinkholes in the mantling detritus is well developed in southwestern Newfoundland and in central and northern Nova Scotia. Covered karst is abundant on sulfates conformably overlain by carbonate br elastic strata; collapse sinkholes ale the principal landform. Very large breccia pipes (up to 25 x 15 km) ale associated with deep subrosion of salt during glacier recessions. Syngenetic breccia karst is a fourth, distinct category created in some formations of thin, interbedded dolostones and sulfates. Where these are exposed td high hydraulic gradients, deep calcite-cemented breccias were formed in a first generation, upon which sinkhole and pinnacle karsts and dissolution drape topographies were able to develop rapidly in late-glacial and post-glacial conditions

Risk assessment methodology for karst aquifers .2. Solute-transport modeling, 1997,
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Field Ms,
Ground-water flow and solute-transport simulation modeling are major components of most exposure and risk assessments of contaminated aquifers. Model simulations provide information on the spatial and temporal distributions of contaminants in subsurface media but are difficult to apply to karst aquifers in which conduit flow is important. Ground-water flow and solute transport in karst conduits typically display rapid-flow velocities, turbulent-flow regimes, concentrated pollutant-mass discharge, and exhibit open-channel or closed-conduit how Conventional groundwater models, dependent on the applicability of Darcy's law, are inappropriate when applied to karst aquifers because of the (1) nonapplicability of Darcian-flow parameters, (2) typically nonlaminar flow regime, and (3) inability to locate the karst conduits through which most flow and contaminant transport occurs. Surface-water flow and solute-transport models conditioned on a set of parameters determined empirically from quantitative ground-water tracing studies may be effectively used to render fate-and-transport values of contaminants in karst conduits. Hydraulic-flow and geometric parameters developed in a companion paper were used in the surface-water model, TOXI5, to simulate hypothetical slug and continuous-source releases of ethylbenzene in a karst conduit. TOXI5 simulation results showed considerable improvement for predicted ethylbenzene-transport rates and concentrations over qualitative tracing and analytical ground-water model results. Ethylbenzene concentrations predicted by TOXI5 simulations were evaluated in exposure and risk assessment models

Isolated carbonate platform of Caniego, Spain: A test of the latest Albian worldwide sea-level changes, 1997,
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Fernandezmendiola Pa, Garciamondejar J,
The upper Albian Caniego carbonate platform consists of a 20-m-thick unit of rudist- and coral-bearing limestones that crops out at the northern margin of the Mena diapir in northern Spain, The limestones were deposited on top of a slowly subsiding area, the Mena paleohigh, a diapiric-induced horst bounded by synsedimentary faults, The Caniego limestones originated in shallow warm tropical waters following a widespread marine transgression at the base of the foraminifera Rotalipora appenninica zone (ammonite Stoliczkaia dispar zone), Around the middle part of the appenninica zone the Caniego limestones underwent subaerial exposure and karst development, Fibrous calcite cements filled the bulk of the fissure-dike and dissolution cavities, Field, petrological, and geochemical data indicate that the fibrous calcites are meteoric flowstones, delta(18)O values in these cements range from -3 parts per thousand to -4.5 parts per thousand and delta(13)C values range from -7 parts per thousand to -14 parts per thousand (relative to the Peedee belemnite [PDB] standard), Thick wedges of nearshore shallow-marine siliciclastic sediments were deposited in paleotrough areas surrounding the Caniego paleohigh while the platform was subaerially exposed, The carbonate platform was drowned in early Cenomanian time and hardground-condensed facies developed during this period (Rotalipora brotzeni zone), Deeper water noncondensed marry sedimentation was reestablished in the mid-Cenomanian (Rotalipora reicheli zone), Comparison of the Iberian Caniego limestones with worldwide successions suggests a coincidence in the timing of platform formation emergence and drowning in several basins of different lithospheric plates, Nevertheless, an overall lack of coordination of sea-level histories from different basins may be related to tectonic movements of the lithospheric plates, Plate rearrangement is invoked as the primary control on relative sea-level changes and sequence development

Groundwater circulation and geochemistry of a karstified bank-marginal fracture system, South Andros Island, Bahamas, 1997,
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Whitaker Fiona F. , Smart Peter L. ,
On the east coast of South Andros Island, Bahamas, a major bank-marginal fracture system characterised by vertically extensive cavern systems (blue holes) is developed sub-parallel to the steep-sided deep-water re-entrant of the Tongue of the Ocean. In addition to providing a discharge route for meteoric, mixed and geochemically evolved saline groundwaters, a strong local circulation occurs along the fracture system. This generates enhanced vertical mixing within voids of the fracture system, evidenced by the increasing mixing zone thickness, and the thinning and increasing salinity of brackish lens waters from north to south along the fracture system. Furthermore, tidally driven pumping of groundwaters occurs between the fracture and adjacent carbonate aquifer affecting a zone up to 200 m either side of the fracture.The resultant mixing of groundwaters of contrasting salinity and within and along the fracture system and with the surrounding aquifer waters, together with bacterial oxidation of organic matter, generates significant potential for locally enhanced diagenesis. Undersaturation with respect to calcite within the fresh (or brackish)-salt water mixing zone is observed in the fracture system and predicted in the adjacent aquifer, while mixing between the brackish fracture lens and surrounding high fresh waters causes dissolution of aragonite but not calcite. The latter gives rise to considerable secondary porosity development, because active tidal pumping ensures continued renewal of dissolutional potential. This is evidenced by calcium and strontium enrichment in the brackish lens which indicates porosity generation by aragonite dissolution at a maximum rate of 0.35% ka-1, up to twice the average estimated for the fresh water lens. In contrast saline groundwaters are depleted in calcium relative to open ocean waters suggesting the formation of calcite cements.The development of a major laterally continuous cavernous fracture zone along the margin of the carbonate platform permits enhanced groundwater flow and mixing which may result in generation of a diagenetic `halo' at a scale larger than that generally recognised around syn-sedimentary fractures in fossil carbonates. This may be characterised by increased secondary porosity where a relative fall in sea-level results in exposure and formation of a meteoric groundwater system, or cementation by `marine' calcite both below this meteoric system, and where the bank surface is flooded by seawater

Radon transport phenomena studied in Karst caves-international experiences on radon levels and exposures, 1997,
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Hakl J. , Hunyadi I. , Csige I. , Geczy G. , Lenart L. , Varhegyi A. ,
The results of radon measurements in caves obtained by using of nuclear track detectors are summarized. Mean radon concentrations are ranging worldwide from 0.1 to 20 kBqm-3 with 2.8 kBqm-3 arithmetic average. From long-term extended radon measurements in caves not only a detailed dosimetric picture can be drawn, but using radon gas as a radioactive tracer, the subsurface and near-to-surface transport processes can be studied, too. It will be shown that long-term radon monitoring by nuclear track detectors, in conjunctions with active detectors which enables detection of fast dynamic changes, offers very important information for naturally-occurring transport processes

Karst Development and Speleogenesis, Isla de Mona, Puerto Rico, 1998,
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Frank, E. F. , Mylroie, J. , Troester, Jo. , Alexander, Jr. , E. C. , Carew, J.
Isla de Mona consists of a raised table-top Miocene-Pliocene reef platform bounded on three sides by vertical cliffs, up to 80 m high. Hundreds of caves ring the periphery of the island and are preferentially developed in, but not limited to, the Lirio Limestone/Isla de Mona Dolomite contact. These flank margin caves originally formed at sea level and are now exposed at various levels by tectonic uplift of the island (Frank 1983; Mylroie et al. 1995b). Wall cusps, a characteristic feature of flank margin caves, are ubiquitous features. Comparisons among similar caves formed in the Bahamas and Isla de Mona reveal the same overall morphology throughout the entire range of sizes and complexities. The coincidence of the primary cave development zone with the Lirio Limestone/Isla de Mona Dolomite contact may result from syngenetic speleogenesis and dolomitization rather than preferential dissolution along a lithologic boundary. Tectonic uplift and glacioeustatic sea level fluctuations produced caves at a variety of elevations. Speleothem dissolution took place in many caves under phreatic conditions, evidence these caves were flooded after an initial period of subaerial exposure and speleothem growth. Several features around the perimeter of the island are interpreted to be caves whose roofs were removed by surficial denudation processes. Several large closed depressions and dense pit cave fields are further evidence of surficial karst features. The cliff retreat around the island perimeter since the speleogenesis of the major cave systems is small based upon the distribution of the remnant cave sections.

An overview of the geology of the Transvaal Supergroup dolomites (South Africa), 1998,
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Eriksson Pg, Altermann W,
In the Neoarchaean intracratonic basin of the Kaapvaal craton, between approximately 2640 Ma and 2516 Ma, two successive stromatolitic carbonate platforms developed. Deposition started with the Schmidtsdrif Subgroup, which is probably oldest in the southwestern part of the basin, and which contains stromatolitic carbonates, siliciclastic sediments and minor lava flows. Subsequently, the Nauga formation carbonates were deposited on peritidal flats located to the southwest and were drowned during a transgression of the Transvaal Supergroup epeiric sea, around 2550 Ma ago. This transgression led to the development of a carbonate platform in the areas of the preserved Transvaal and Griqualand West basins, which persisted for 30-50 Ma. During this time, shales were deposited over the Nauga Formation carbonates in the south-western portion of the epeiric sea. S subsequent period of basin subsidence led to drowning of the stromatolitic platform and to sedimentation of chemical, iron-rich silica precipitates of the banded iron formations (BIF) over the entire basin. Carbonate precipitation in the Archaean was largely due to chemical and lesser biogenic processes, with stromatolites and ocean water composition playing an important role. The stromatolitic carbonates in the preserved Griqualand West and Transvaal basins are subdivided into several formations, based on the depositional facies, reflected by stromatolite morphology, and on a intraformational unconformities; interbedded tuffs and available radiometric age data do not ye permit detailed correlation of units from the two basins. Thorough dolomitisation of most formations took place at different post-depositional stages, but mainly during early diagenesis. Partial silification was the result of diagenetic and weathering processes. Karstification of the carbonate rocks was related to periods of exposure to subaerial conditions and to percolation of groundwater. Such periods occurred locally at the time of carbonate and BIF deposition. Main karstification, however, probably took place during an erosional period between approximately 2430 Ma and 2320 Ma

Paleomagnetic study of Triassic sediments from the Silica Nappe in the Slovak Karst, a new approach, 1998,
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Kruczyk J. , Kadzialkohofmokl M. , Tunyi I. , Pagac P. , Mello J. ,
Intensive paleomagnetic and rock magnetic study were performed for Triassic limestones from the Silica Nappe in the Slovak Karst. Five exposures situated on the eastern and western side of the Stitnik-Plesivec fault were sampled for this study. In all exposures a secondary component of remanence of normal polarity (N), carried by secondary PSD magnetite was found. In the Silicka Brezova exposure (SE) apart from the N component, another secondary component of reversed polarity (R), carried by hematite; was isolated. Both components were acquired after folding. The R component was acquired during the Odra reversal event in the Oligocene (Birkenmajer et al. 1977). Comparison of its direction with the reference data let us conclude that the area belonged during this time to the African affinity. The declination of the R component suggests that after this magnetization period the studied region rotated anticlockwise by about 90 degrees around an intraplate vertical axis together with the whole Pelso megaunit. According to Marton et al. (1995) and Marton & Fodor (1995) the rotation took place in two phases, the first one by about 50 degrees took place in the Early Miocene, the second one, by about 30 degrees - in the Late Miocene. The N component, isolated by us, seems to have been acquired during the Middle Miocene after the first and before the second rotational phases: its declination agrees with a counterclockwise rotation of the Silica Nappe by about 30-40 degrees during the Late Miocene, as postulated by the cited authors. The inclination of the N component is lower, than the expected for Miocene, but agrees with the Miocene results for the Bukk region also belonging to the Pelso block, confirming the idea about the Miocene 'southern escape' of the Pelso block (Marton 1993). The final tectonic activity in the study area was connected with formation of the Stitnik-Plesivec fault (Late Tertiary-Quaternary). Our results suggest, that the fault is of rotational type and resulted in different tilting of beds situated on its eastern and western sides

Holocene development of three isolated carbonate platforms, Belize, central America, 1998,
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Gischler E. , Hudson J. H. ,
Locally operating factors such as topography of the reef basement and exposure to waves and currents rather than regionally effective factors such as the post-glacial sea level rise in the western Atlantic explain the different Holocene developments of the three isolated carbonate platforms Glovers Reef, Lighthouse Reef, and Turneffe Islands offshore Belize. A series of NNE-striking tilted fault-blocks at the passive continental margin forms the deep basement of the Belize reefs. Glovers and Lighthouse Reefs are located on the same fault-block, while Turneffe Islands is situated west of Lighthouse Reef on an adjacent fault-block. The three platforms are surrounded by deep water and have surface-breaking reef rims. Significant differences exist between platform interiors. Glovers Reef has only 0.2% of land and an 18 m deep, well-circulated lagoon with over 800 patch reefs. Lighthouse Reef has 3% of land and a well-circulated lagoon area. Patch reefs are aligned along a NNE-striking trend that separates a shallow western (3 m) and a deeper eastern (8 m) lagoon. Turneffe Islands has 22% of land that is mainly red mangrove. Interior lagoons are up to 8 m deep and most have restricted circulation and no patch reefs. Surface sediments are rich in organic matter. In contrast, the northernmost part of Turneffe Islands has no extensive mangrove development and the well-circulated lagoon area has abundant patch reefs. Holocene reef development was investigated by means of 9 rotary core holes that all reached Pleistocene reef limestones, and by radiometric dating of corals. Maximal Holocene reef thickness reaches 11.7 m on Glovers Reef, 7.9 m on Lighthouse Reef, and 3.8 m on Turneffe Islands. Factors that controlled Holocene reef development include the following. (1) Holocene sea level. The margin of Glovers Reef was flooded by the rising Holocene sea ca. 7500 YBP, that of Lighthouse Reef ca. 6500 YBP, and that of Turneffe Islands between 5400 and 4750 YBP. All investigated Holocene reefs belong to the keep-up type, even though the three platforms were flooded successively and, hence, the reefs had to keep pace with different rates of sea level rise. (2) Pre-Holocene topography. Pleistocene elevation and relief are different on the three platforms. This is the consequence of both tectonics and karst. Different elevations caused successive reef initiation and they also resulted in differences in lagoon depths. Variations in Pleistocene topography also explain the different facies distribution patterns on the windward platforms that are located on the same fault-block. On Lighthouse Reef tectonic structures are clearly visible such as the linear patch reef trend that is aligned along a Pleistocene fault. On Glovers Reef only short linear trends of patch reefs can be detected because the Pleistocene tectonic structures are presumably masked by the higher Holocene thickness. The lower Pleistocene elevation on Glovers Reef is probably a consequence of both a southward tectonic tilt, and stronger karstification towards the south related to higher rainfall. (3) Exposure to waves and currents. Glovers Reef, Lighthouse Reef, and the northernmost part of Turneffe Islands receive the maximum wave force as they are open to the Caribbean Sea. Adjacent lagoons are well-circulated and have luxuriant patch reef growth and no extensive mangrove development. By contrast, most of Turneffe Islands is protected from the open Caribbean Sea by Lighthouse Reef to the east and is only exposed to reduced wave forces, allowing extensive mangrove growth in these protected areas. (C) 1998 Elsevier Science B.V

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