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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 thermocline is an intermediate layer in stratified water [16].?

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

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Browse Speleogenesis Issues:

KarstBase a bibliography database in karst and cave science.

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 yield (Keyword) returned 178 results for the whole karstbase:
Showing 31 to 45 of 178
A Radiocarbon Date of 380 60 bp for a Taino site, Cueva Negra,Isla de Mona, Puerto Rico, 1998,
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Frank, E. F.
Charcoal fragments were collected from a mixed charcoal and bone deposit from a chamber in Cueva Negra, Isla de Mona Puerto Rico. Radiocarbon dating yielded a conventional 14C age of 380 60 Radiocarbon Years before present. Considering the standard deviation in the 14C data, the range in possible calendar dates is from 1480 to 1655 AD. This time period encompasses the first contact between Taino population and Europeans, and the subsequent removal of the last of the Taino from the island to Puerto Rico in 1578.

An experimental study of calcite and limestone dissolution rates as a function of pH from -1 to 3 and temperature from 25 to 80 degrees C, 1998,
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Alkattan M, Oelkers Eh, Dandurand Jl, Schott J,
Dissolution rates of single calcite crystals, limestones, and compressed calcite powders were determined from sample weight loss using free-drift rotating disk techniques. Experiments were performed in aqueous HCl solutions over the bulk solution pH range -1 to 3, and at temperatures of 25 degrees, 50 degrees, and 80 degrees C. Corresponding rates of the three different sample types are identical within experimental uncertainty. Interpretation of these data using equations reported by Gregory and Riddiford [Gregory, D.P., Riddiford, A.C., 1956. Transport to the surface of a rotating disc. J. Chem. Sec. London 3, 3756-3764] yields apparent rate constants and H diffusion coefficients. The logarithms of overall calcite dissolution rates (r) obtained at constant disk rotation speed are inversely proportional to the bulk solution pH, consistent with r = k(2') a(H,b), where k(2)' stands for an apparent rate constant and a(H,b) designates the hydrogen ion activity in the bulk solution, This variation of dissolution rates with pH is consistent with corresponding rates reported in the literature and the calcite dissolution mechanism reported by Wollast [Wollast, R., 1990. Rate and mechanism of dissolution of carbonates in the system CaCO3-MgCO3. In: Stumm, W. (Ed.), Aquatic Chemical Kinetics. Wiley, pp. 431-445]. Apparent rate constants for a disk rotation speed of 340 rpm increase from 0.07 0.02 to 0.25 0.02 mol m(-2) s(-1) in response to increasing temperature from 25 degrees to 80 degrees C. H diffusion coefficients increase from (2.9 to 9.2) x 10(-9) m(2) s(-1) over this temperature range with an apparent activation energy of 19 kJ mol(-1). (C) 1998 Elsevier Science B.V. All rights reserved

Estimating subsurface fissure apertures in karst aquifers from equilibrium activities, 1998,
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Field Ms, Mose Dg,
Rn-222 activities were determined for the karst aquifer underlying Walkersville, Maryland, in an area of ground-water discharge from a single geological unit during the summer and fall seasons, Radon-222 equilibrium activities in karst ground waters can be employed in mass-balance models to estimate microfissure, macrofissure, and conduit aperture dimensions, This approach defines Rn-222 generation and loss in karst aquifers as a function of fissure apertures and the U-238 content of the rock, High Rn-222 activities occur in tight fissures and low Rn-222 activities occur in conduits, In the vadose zone, Rn-222 activities are low as a result of degassing, especially if flow is turbulent and activities are decoupled from the phreatic zone, In the phreatic zone, if recharge to fissures causes a reduction of residence time below that required for equilibrium (approximate to 26 days), Rn-222 activities fall, At springs and in the vadose zone, after a rainfall event, Rn-222 activities increase as waters with long residence and with high Rn-222 activities are expelled from fissure and fracture storage, Field data and selected literature values were used to test the model, Models used to predict median microfissure apertures for this karst aquifer yield aperture estimates ranging from 2.8 mu m to 9.2 mu m. Median macrofissure apertures ranged from 5.53 cm to 5.88 cm, Median conduit apertures ranged from 1.16 m to 1.24 m, Comparison of the models results with published data on karst aquifers and observations at the field site suggest that the predicted apertures are reasonable

Geomorphology of the Tertiary gypsum formations in the Ebro Depression (Spain), 1998,
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Elorza Mg, Santolalla Fg,
This paper reviews the current knowledge of the mainly karstic geomorphological features developed in the evaporitic formations of the Ebro Depression (northern Spain). Special emphasis is given to the recently published and unpublished scientific advances. The gypsum formations, of Tertiary age, have an extensive outcrop area within the Ebro Depression. Here, their morphogenesis is controlled mainly by processes of surface and subsurface dissolution acting on the gypsum. Outstanding landforms in the gypsum terrain include saline lakes developed in flat bottom dolines (saladas). Other characteristic morphologies include karren and gypsum domes, which occur on a decimetre scale. Where the gypsum is covered by Quaternary alluvial deposits the karstification processes are especially intense and cause subsidence phenomena. Karstic subsidence affects stream terraces, mantled pediments and infilled valleys, which in the region are called vales. Dissolution-induced synsedimentary subsidence has produced interesting geological features, which include significant thickening and deformation of the alluvial deposits. In contrast to the rapid removal of gypsum by dissolution, the amount of gypsum removed by erosion is low. Water erosion studies carried out on gypsiferous slopes of the Ebro Depression, indicate that the sediment yield ranges from 0.59 to 7.82 t/ha/year. This low yield results from the high infiltration capacity of the soils. Subsidence caused by gypsum dissolution has important socioeconomic consequences in the Ebro Depression. The active alluvial karstification of the gypsum causes numerous sinkholes that are harmful to linear structures (roads, railway Lines, irrigation channels), buildings and agricultural land. Unforeseen catastrophic subsidence also puts human Lives at risk. The benefits of such terrains include thickened alluvial deposits which act as valuable water reservoirs and which form excellent sources of aggregates. Fluvial valleys in this gypsiferous terrain commonly show an asymmetrical geometry with prominent gypsum scarps at one side. These gypsum scarps are affected by numerous landslides. These slope movements are hazardous, may dam rivers and cause flooding of the alluvial plains. (C) 1998 Elsevier Science B.V. All rights reserved

Speleothem-based paleoclimate record from northern Oman, 1998,
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Burns Sj, Matter A, Frank N, Mangini A,
U-Th age dating and stable isotope measurements of speleothems from Hoti Cave in northern Oman yield paleoclimate information from the region extending to 125 ka. The results (1) provide further confirmation of an early Holocene wet period in southern Arabia extending from some time prior to 9.7 ka and ending at 6.2 ka; (2) demonstrate a second period of wetness closely coinciding with the last interglacial period, marine isotope stage (MIS) 5e; (3) indicate that during MIS 5e, southern Arabia was considerably wetter than during the early Holocene; and (4) demonstrate that periods of increased monsoon wind strength, based on data from marine sediments, do not always coincide with evidence of greatly increased precipitation even from nearby continental areas

The dynamics of flowstone deposition in the caves Postojnska, Planinska, Taborska and Škocjanske, Slovenia , 1998,
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Gams Ivan, Kogovš, Ek Janja

The results of flowstone deposition measurements in the caves Postojnska, Planinska, Taborska and Škocjanska Jama of the Slovene karst are given. From 0 to 180 mg of CaCO3 are precipitated from 1 litre of percolation water. The drippings during one year yield average 40 g of flowstone out of 1 m3 of percolation water; in the case of Orjaki, Škocjanske Jame, the deposition is even higher. Comparison of measurements of percolation water flowing either over the speleothems or over sheets of glass in Postojnska Jama since 1963 have shown numerous factors controlling the flowstone deposition. The quantity of precipitated flowstone expotentially increases by the growth of speleothem when water washes larger surfaces of the speleothem. Gravimetric determination of flowstone deposition on sheets of glass (61x18 cm) gave in 34 years an average flowstone growth of 0.11 mm per year.

Pleistocene small mammals from some karstic fillings of Slovenia - preliminary results, 1998,
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Aguilar Jeanpierre, Crochet Jeanyves, Krivic Katarina, Marandat Bernard, Michaux Jacques, Mihevc Andrej, Sigé, Bernard, Š, Ebela Stanka

The discovery of Pleistocene small mammals in karstic fillings of Slovenia is reported here. The rodent faunas collected there are mainly composed of arvicolids, murids and to a lesser degree of cricetids, although in one filling only glirids have been recorded yet. Six species of Lipotyphlan insectivores have been identified. A cave filling has yielded bats which belong to species different of those which occupy the cave to date.

Hydrogeology of Kartchner Caverns State Park, Arizona, 1999,
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Graf, C. G.
Three distinct hydrogeologic systems occur within Kartchner Caverns State Park, Arizona, each in fault contact with the other two. The southeastern corner and eastern edge of the park is part of the large graben that formed the San Pedro Valley during Miocene Basin and Range faulting. A thick alluvial sequence fills this graben and contains a regional aquifer covering 1000 km. One well in the park penetrates this aquifer. The groundwater level measured in this well was 226 m below land surface (1167 m msl), which is 233 m lower than the lowest measured point inside of Kartchner Caverns (1400 m msl). A pediment occupies a small part of the southwestern corner of the park. Structurally, this feature is part of the Whetstone Mountains horst rising above the park to the west. The pediment consists of a bedrock surface of Precambrian Pinal Schist overlain by a few tens of meters of granite wash sediments. Groundwater occurs at depths of 4-18 m below land surface in wells tapping the granite wash sediments. Data from these wells indicate that the zones of saturation within the granite wash sediments are probably of limited lateral extent and yield little water to wells. At the boundary between the pediment and the carbonate ridge containing Kartchner Caverns, the water table in the granite wash aquifer is 20 m higher than the bottom of the nearest known cave passage, located about 200 m to the east.The arid carbonate hills occupying the northwestern part of the park are the erosional remnants of a fault block (the Kartchner Block) that was displaced downward with respect to the Whetstone Mountains horst to the west. Kartchner Caverns is wholly contained in a ridge of highly faulted Mississippian Escabrosa Limestone and cuts conspicuously across Escabrosa beds dipping 10-40 to the southwest and west. Meteoric water enters the Kartchner Block and Kartchner Caverns from infiltration of runoff in washes that border the block and from overhead infiltration of precipitation. A small amount of groundwater also may flow into the Kartchner Block from the schist pediment to the south. Response in the cave to these fluxes is slow. As calculated from past records, the probability of flooding in the cave in any one year is about 57%.

Estimates of Population Size of Stygobromus emarginatus (Amphipoda: Crangonyctidae) in a Headwater Stream in Organ Cave, West Virginia, 1999,
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Knapp, S. M. , Fong, D. W.
Population sizes of Stygobromus emarginatus were estimated using mark-recapture data at three sites each in two habitats of a headwater stream in the Organ Cave drainage. The stream channel habitat contained an average of 10 to 14 individuals per meter length and an estimated population size of 3000 to 4200 individuals. The pool habitat yielded very low recapture rates. We argue that the pool habitat represents a window into the epikarstic zone, and the low recapture rates indicate a large hidden population in the epikarst

Planning for gypsum geohazards in Lithuania and England, 1999,
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Paukstys B. , Cooper A. H. , Arustiene J. ,
The rapid underground dissolution of gypsum, and the evolution of the gypsum karst in Lithuania and England, results in subsidence problems which can make construction difficult. The natural dissolution yields sulphate-rich groundwater of poor quality and the karst is susceptible to the rapid transmission of pollutants. In the north of Lithuania gypsum karst is developed in Devonian gypsum. Here the towns of Birai, Pasvalys and the surrounding countryside suffer subsidence and some buildings have been damaged. The majority of the potable water in these areas is derived from groundwater extracted from sandstone sequences that underlie the gypsum. In Lithuania conservation measures have been introduced to control agriculture and prevent pollution of the gypsum karst. These measures include environmentally-friendly farming, restrictions on land use and exclusion zones around subsidence hollows. In England subsidence caused by the dissolution of Permian gypsum has caused severe problems in the vicinity of the town of Ripen. Numerous buildings have been damaged and new sites are difficult to develop. Here formal planning regulations have recently been introduced to help to protect against the worst effects of subsidence resulting from gypsum dissolution. (C) 1999 Elsevier Science B.V. All rights reserved

Relationships between karst and tectonics: case-study of the cave system north of Lake Thun (Bern, Switzerland): Relations entre karst et tectonique : l'exemple du reseau speleologique du nord du lac, 1999,
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Hauselmann Philipp, Jeannin Pierre Yves, Bitterli Thomas,
The cave system is situated north of Lake Thun, in the Helvetic border chain. The overall geology is simple: the slightly dipping (15-25[deg] towards the southeast) strata are interrupted by a NE-SW trending normal fault with a throw of 150 m in the NE and about 500 m in the SW. Since a part of the region is covered by flysch, the caves are the only way to observe the geological setting of the underlying Cretaceous and Eocene series. We show that observations in caves may yield valuable information about the onset of the tectonic movements: in particular, observations in the Barenkluft region clearly demonstrate that the beginning of prealpine extension had already begun in the Upper Cretaceous, and that this normal fault has been inverted later during Alpine compression. We also illustrate the influence of tectonic stress and strain upon karstification. The Alpine tectonic phases, with alternating compression and extension, contributed to the development of different karstogenetic levels. Tectonic strains opened and possibly closed some fractures, allowing (or preventing) water to flow through parts of the karst massive. The structural setting, defining the overall geometry of the limestone bed, played an important role in the development of the various phases of the system. Most of the conduits appear to belong to old, deep phreatic systems. Tectonics is only one of a number of factors controlling karstification. Together with lithology, it represents the geological control. Geomorphological factors (mainly spring and catchment positions, but also erosion of the flysch cover), as well as bioclimatical factors (quantity and physico-chemical characteristics of water), and hydrodynamics and transport processes can play a significant role on the genesis of karst systems

Perspectives in karst hydrogeology and cavern genesis, 1999,
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Ford D. C.
Hydrogeology and speleology both began during the 19th CenturyTheir approaches to limestone aquifers diverged because hydrogeologists tend to measure phenomena at very local scales between drilled wells and generalize from them to basin scales, while speleologists study the large but sparse conduits and then infer conditions around themConvergence of the two approaches with modem computing should yield important genetic models of aquifer and caveGenesis of common cave systems by dissolution is a three-dimensional problem, best broken down into two-dimensional pairs for purposes of analysisHistorically, the dimensions of length and depth have received most attention, especially the question of the location of principal cave genesis with respect to the water tableBetween 1900 and 1950, different scientists proposed that caves develop principally (1) in the vadose zone; (2) at random depth in the phreatic zone; (3) along the water table in betweenEmpirical evidence suggests that these differing hypotheses can be reconciled by a four-state model in which the frequency of penetrable fissuration controls the system geometryFor the dimensions of length and breadth (plan patterns) there is widespread agreement that dendritic (or branchwork) patterns predominate in common cavesIrregular networks or anastomose patterns may occur as subsidiary componentsWhen hydraulic conditions in a fissure are anisotropic (the usual case), dissolutional conduit development is competitive: local hydraulic gradients are reoriented toward the first conduits to break through to outlet points, redirecting others toward them in a cascading processPlan patterns are most complex where there have been multiple phases ("levels") of development in a cave system in response to such effects as river channel entrenchment lowering the elevation of springs

Role of cave information in environmental site characterization,, 1999,
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Jancin M.
For consultants concerned with developing site-specific conceptual models for flow and transport in karst, cave information can be worth accessingAt the scale of the basin, caves often display patterns that correlate with both the flow and recharge characteristics of their aquifersCharacterization of overall basin hydrology bolsters predictions and monitoring recommendations which address the siteAlthough the presence of caves beneath or near sites is rare, site-based information such as water-table maps (under both natural and pumping conditions), well water-level fluctuations, well turbidity observations, borehole-void yields during drilling, and dye-trace results, are potentially useful in defining conduit-flow boundaries to diffuse-flow blocksThe appropriate choice of dye-tracer methods should acknowledge whether most site conduits (or borehole voids, or even caves) are within the epikarst, the vadose zone, the phreatic zone, or the oscillation zoneFor inferences on site flow directions, it is useful to compare the directional frequencies of cave passages and joints, faults, and photolinears in the areaThere is evidence that where caves are well developed, there tends to be a low correlation between photolinear locations and relatively high well yieldsLNAPL migration will be retarded where main conduits are well beneath the water table, but an extensive overlying system of saturated epikarstic pores serve as trapsKarst with high seasonal or storm variations in water level will tend to repeatedly remobilize LNAPLsGiven sufficient volume, DNAPLs can penetrate vertically integrated networks of pores, fractures, or solution conduits to great depthHowever, where such pathway networks are lie above relatively tight lithologies at shallow depth, and are not sediment filled, lateral movement can greatly exceed vertical movementCharacterization of the 3-D nature of pores and pathways is an important element in understanding the migration of free product, and therefore in understanding the evolution of associated aqueous plumes

Results of a Speleothem U/Th Dating Reconnaissance from the Helderberg Plateau, New York, 2000,
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Lauritzen, S. E. , Mylroie, J. E.
The Helderberg Plateau consists of Silurian-Devonian carbonates that crop out across central New York State, supporting a well-developed, multiply glaciated karst. Stalagmites and flowstone were collected from five caves spread across a 60 km long traverse of the Plateau from Albany west-northwest to Schoharie County. Subsamples from these spleothems yielded 36 U/Th alpha count dates ranging from 3 ka to >350 ka. While the data reported here are only a reconnaissance study, they represent the most comprehensive geochronologic data base for any karst area in the northeastern United States. Hollyhock Hollow, southern Albany County: two cave-fill samples yielded three dates of 70-56 ka and four dates of 41-35 ka; the mid-Wisconsin dates may reflect the caves southerly position. Onesquethaw Cave, central Albany County: two stalagmites yielded 5 dates, all Holocene (<9 ka); the dates suggest that Onesquethaw Cave may be post-glacial in origin. Caboose Cave, eastern Schoharie County: five stalagmite and flowstone samples provided 13 dates, ranging from 207-56 ka, with distinct clusters at 100-56 ka and 207-172 ka; the dates support the cave being older than the last glaciation. Schoharie Caverns, 2 km west of Caboose Cave: six samples from one flowstone all dated to >350 ka; the dates indicate that the cave has survived more than one glaciation. Barrack Zourie Cave, western Schoharie County: two stalagmites yielded four dates, which cluster at 161-158 ka, with a younger overgrowth at 61 ka (two previously reported dates were 165 ka and 277 ka); the dates support the cave being older than the last glaciation. The U/Th dates indicate that both pre- and post-glacial caves exist in New York. The dates cluster in the 100-56 ka and 207-158 ka range, and there are a surprising lack of dates from the last interglacial (130-120 ka), possibly an artifact of the sampling regime.

Transmissivity estimates from well hydrographs in karst and fractured aquifers, 2000,
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Powers J. G. , Shevenell L. ,
Hydrograph recessions from rainfall events have been previously analyzed for discharge at springs and streams; however, relatively little quantitative research has been conducted with regard to hydrograph analysis of recessions from monitoring wells screened in karst aquifers, In previous work, a quantitative hydrograph analysis technique has been proposed from which matrix transmissivity (i.e., transmissivity of intergranular porosity) and specific yields of matrix, fracture, and conduit components of the aquifer may be determined from well hydrographs, The technique has yielded realistic results at three sites tested by the authors (Y-12, Oak Ridge, Tennessee; Crane, Indiana; and Fort Campbell, Kentucky). Observed field data, as well as theoretical considerations, show that karst wed hydrographs are valid indicators of hydraulic properties of the associated karst aquifers, Results show matrix transmissivity (T) values to be in good agreement with values calculated using more traditional parameter estimation techniques, such as aquifer pumping tests and slug tests in matrix dominated wells. While the hydrograph analysis technique shows premise for obtaining reliable estimates of karst aquifer T with a simple, relatively inexpensive and passive method, the utility of the technique is limited in its application depending on site-specific hydrologic conditions, which include shadow submerged conduit systems located in areas with sufficient rainfall for water levels to respond to precipitation events

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