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Speleology in Kazakhstan

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

New publications on hypogene speleogenesis

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

The deepest terrestrial animal

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

Caves - landscapes without light

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

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That leg is a part of a survey traverse between two successive stations [25].?

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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 mature karst (Keyword) returned 11 results for the whole karstbase:
Agricultural land use effects on nitrate concentrations in a mature karst aquifer, 1996, Boyer Dg, Pasquarell Gc,
The impact on water quality by agricultural activity in karst terrain is an important consideration for resource management within the Appalachian Region. Karst areas comprise about 18 percent of the Region's land area. An estimated one-third of the Region's farms, cattle, and agricultural market value are on karst terrain. Nitrate concentrations were measured in cave streams draining two primary land management areas. The first area was pasture serving a beef cow-calf operation. The second area was a dairy. Nitrate-N concentrations were highest in cave streams draining the daily and a cave stream draining an area of pasture where cattle congregate for shade and water. The dairy contributed about 60 to 70 percent of the nitrogen load increase in the study section of the cave system. It was concluded that agriculture was significantly affecting nitrate concentrations in the karst aquifer. Best management practices may be one way to protect the ground water resource

Organic matter in the Upper Silesian (Mississippi Valley-type) Zn-Pb deposits, Poland, 1999, Sassgustkiewicz M. , Kwiecinska B. ,
Organic matter contained in large amounts in the Upper Silesian Zn-Pb ore deposits has been identified as dopplerite-calcium humate. This humic, amorphous substance was precipitated from humic acids by calcium ion loading. The precipitation of dopplerite was contemporaneous with sulfide deposition at the time of initial and mature karst processes. The hydrothermal karst dissolution supplied calcium ions but the source of humic acids is still conjectural. The geochemical data indicate that the most probable source for the organic matter deposited in the Zn-Pb ores are overlying Triassic Keuper shales containing dispersed humic organic substance

Recent developments in knowledge of the hydrogeology of the Classical Karst, 2000, Cucchi Franco, Forti Paolo, Marinetti Enrico, Zini Luca

The Classical Karst may well be the best area for polythematic researches. It would be useful to understand karst phenomena and create a hydrogeological model valid for all mature karst. The Karst area is quite well studied and known. The geology, hydrology and its history have been studied since the 16th century. Nowadays the continuous monitoring of hypogean waters, the elaboration of a Digital Elevation Model, the discovery of some new caves and their study has permited the processing of the vulnerability map. On the basis of the results of all of these researches, we propose activating a co-operation between European researchers to develop hydrodynamic models of the most well known karst in the world: the Classical Karst


The engineering classification of karst with respect to the role and influence of caves, 2002, Waltham Tony
The engineering classification of karst defines various complexities of ground conditions, in terms of the hazards that they provide to potential construction. Karst is divided into five classes (from immature to extreme). The three key parameters within the classification are caves (size and extent), sinkholes (abundance and collapse frequency) and rockhead (profile and relief). As one component of karst, caves are a hazard to foundation integrity, though natural surface collapses over caves are extremely rare. A cave roof is normally stable under engineering loading where the roof thickness is greater than 70% of the cave width. Construction can proceed over or around caves that are known. The main difficulty is finding unseen voids; ground investigation in mature karst may require extensive borehole probing, and microgravity is the most useful geophysical technique.

The hydrogeochemistry of the karst aquifer system of the northern Yucatan Peninsula, Mexico, 2002, Perry E. , Velazquezoliman G. , Marin L. ,
Based on groundwater geochemistry, stratigraphy, and surficial and tectonic characteristics, the northern Yucatan Peninsula, Mexico, a possible analog for ancient carbonate platforms, is divided into six hydrogeochemical/physiographic regions: (1) Chicxulub Sedimentary Basin, a Tertiary basin within the Chicxulub impact crater; (2) Cenote Ring, a semicircular region of sinkholes; (3) Pockmarked Terrain, a region of mature karst; (4) Ticul fault zone; (5) Holbox Fracture Zone-Xel-Ha Zone; and (6) Evaporite Region. Regional characteristics result from tectonics, rock type, and patterns of sedimentation, erosion, and rainfall. The Cenote Ring, characterized by high groundwater flow, outlines the Chicxulub Basin. Most groundwater approaches saturation in calcite and dolomite but is undersaturated in gypsum. Important groundwater parameters are: SO4/Cl ratios related to seawater mixing and sulfate dissolution; Sr correlation with SO4, and saturation of Lake Chichancanab water with celestite. indicating celestite as a major source of Sr; high Sr in deep water of cenotes, indicating deep circulation and contact of groundwater with evaporite; and correlation of Ca, Mg, and SO4, probably related to gypsum dissolution and dedolomitization. Based on geochemistry we propose: (1) a fault between Lake Chichancanab and Cenote Azul; (2) deep seaward movement of groundwater near Cenote Azul; and (3) contribution of evaporite dissolution to karst development in the Pockmarked Terrain. Chemical erosion by mixing-zone dissolution is important in formation of Estuario Celestun and other estuaries, but is perhaps inhibited at Lake Bacalar where groundwater dissolves gypsum, is high in Ca, low in CO3, and does not become undersaturated in calcite when mixed with seawater

Gypsum karst and its evolution east of Hafik (Sivas, Turkey), 2005, Dogan U, Ozel S,
Sivas and its surroundings is the most important gypsum karst terrain in Turkey with a massive Lower Miocene gypsum formation 750 m thick. The region east of Hafik has a wide variety of well developed karstic features such as karrens, dissolution dolines, collapse dolines, blind valleys, karstic springs, swallow holes, caves, unroofed caves, natural bridges, gorges and poljes. The karstification started in the Early Pliocene. The piezometric level to the east of Hafik has lowered at least 200 m since the Early Pliocene and 90-100 m since the Early Pleistocene. There is a youthful karst (doline karst) on the Higher Plateau (1520-1600 m) and a mature karst on Lower Plateau (1315-1420 m). The mature karst evolved in two stages, first stage where excessively karstic paleovalleys, uvalas and collapse dolines appear and the second stage where poljes, collapse dolines and degraded collapse dolines dominated

A quantitative method for the characterisation of karst aquifers based on spring hydrograph analysis, 2005, Kovacs A. , Perrochet P. , Kiraly L. , Jeannin P. Y. ,
This paper presents a method for characterizing flow systems in karst aquifers by acquiring quantitative information about the geometric and hydraulic aquifer parameters from spring hydrograph analysis. Numerical sensitivity analyses identified two fundamentally different flow domains, depending on the overall configuration of aquifer parameters. These two domains have been quantitatively characterized by deducing analytical solutions for the global hydraulic response of simple two-dimensional model geometries. During the baseflow recession of mature karst systems, the hydraulic parameters of karst conduits do not influence the drainage of the low-permeability matrix. In this case the drainage process is influenced by the size and hydraulic parameters of the low-permeability blocks alone. This flow condition has been defined as matrix-restrained flow regime (MRFR). During the baseflow recession of early karst systems and fissured systems, as well as the flood recession of mature systems, the recession process depends on the hydraulic parameters and the size of the low-permeability blocks, conduit conductivity and the total extent of the aquifer. This flow condition has been defined as conduit-influenced flow regime (CIFR). Analytical formulae demonstrated the limitations of equivalent models. While equivalent discrete-continuum models of early karst systems may reflect their real hydraulic response, there is only one adequate parameter configuration for mature systems that yields appropriate recession coefficient. Consequently, equivalent discrete-continuum models are inadequate for simulating global response of mature karst systems. The recession coefficient of equivalent porous medium models corresponds to the transition between matrix-restrained and conduit-influenced flow. Consequently, equivalent porous medium models yield corrupted hydrographs both in mature and early systems, and this approach is basically inadequate for modelling global response of karst aquifers. (c) 2004 Elsevier B.V. All rights reserved

Hazard connected to railway tunnel construction in karstic area: applied geomorphological and hydrogeological surveys, 2005, Casagrande G, Cucchi R, Zini L,
In a mature karstic system, the realisation of galleries using the methodology of railway tunnel boring machine (TBM) involves particular problems due to the high risk of interference with groundwater (often subject to remarkable level variations) and with cavities and/or thick fill deposits. In order to define groundwater features it is necessary to investigate both hydrodynamic and karstification. To define and quantify the karst phenomenon in the epikarst of the Trieste Karst (Italy), an applied geomorphological approach has been experimented with surface and cavity surveys. The surface surveys have contributed to determining the potential karst versus the different outcropping lithologies and to define the structural setting of the rocky mass also through the realisation of geostructural stations and the survey of the main lines thanks to photo-interpretation. Moreover, all the dolines and the cavities present in the area interested by the gallery have been studied by analysing the probable extension of caves and/or of the secondary fill deposits and by evaluating the different genetic models. In an area 900 ra large and 27 km long, which has been studied because of the underground karst, there are 41 dolines having diameters superior to 100 m and 93 dolines whose diameters range between 100 and 50 m; the dolines whose diameters are inferior to 50 m are 282. The entrances of known and registered cavities in the cadastre records are 520. The hypogeal surveys have shown 5 typologies in which it has been possible to group all the cavities present in a hypothetical intersection with the excavation. The comparison between surface and hypogeal structural data and the direction of development of cavities has allowed for the definition of highly karstified discontinuity families, thus having a higher risk. The comparison of the collected data has enabled to identify the lithologies and areas having major risk and thus to quantify the probability of intersection with the different cavity typologies for each area. To make an example, out of 27 000 m of studied gallery 3930 are the metres expected to be at very high 'karst risk'. Out of these, as a whole 3 10 are risky because of the probable presence of gallery cavities, 2170 because of the probable presence of pits and sinkholes diffusely present under the dolines, and along 1450 m karst is particularly intense. Moreover, 2200 should be the metres in which the rocky mass will be particularly divided because of tectonic causes. From a hydrogeological point of view a monitoring of water level has started to quantify water excursion, due to closeness of the railway tunnel to the mean water level. First results related to galleries intersection are here presented

DYNAMIC TOPOGRAPHY, PRESSURIZED SANDSTONES AND HYPOGENE SPELEOGENESIS IN THE OZARKS, 2010,

Large-scale crustal subsidence proposed for the New Madrid region (Forte et al., 2007) can explain the upwelling of saline groundwater in the Northern Mississippi Embayment and parts of the adjacent Ozarks. As rock moves downward, deep groundwater is displaced upward. Raising the Ozarks relative to the Mississippi Embayment increases hydraulic pressure in sandstone aquifers and stresses the interlayered, low-conductivity, telogenetic, carbonates. In response to the increased pressure, groundwater finds new pathways to exit freshwater confined aquifers. Upward cross-formational discharge of deep groundwater can produce cave passages that do not correlate with joints as well as huge spring flows that do not correlate with catchment areas. Recognition of the widespread regional discharge regime in the Ozark region has been hampered by the unfounded assumption of unconfined conditions based on water levels from wells open to large intervals. Recent studies, using techniques such as flow meters, reveal relatively thin, pressurized sandstones at surprisingly high elevations in areas that were once thought to be recharge zones. The pressurized aquifers limit downward infiltration of meteoric recharge and create a complex flow field: a topography-driven meteoric regime perched above an overpressured regime driven by neotectonics. The boundary between the two competing regimes shifts continuously as valleys entrench and karstification changes the hydraulic function of carbonates. As denudation progresses, different parts of the Ozark stratigraphic column are in different karstification zones at the same time. Beneath uplands, groundwater is confined by relatively shallow unfractured carbonates. Ubiquitously ascending waters move upward into sandstone layers and then laterally toward the valleys. Mixing creates large conduits beneath sandstones and eventually unroofing opens fractures in the carbonates, allowing epigenic processes to become dominant. Wells that seal off or miss the upper pressurized sandstone can produce low water levels, a condition the USGS refers to as ‘mature karst’. In epigenic zones near deep valleys, sandstones that extend back into the uplands can continue to supply deep groundwater to perennial cave streams.


Characterizing moldic and vuggy pore space in karst aquifers using borehole-wall, slabbed-core and thin-section images, 2013, Manda A. K. , Culpepper A. R.

Carbonate aquifers are prolific and important sources of potable water in many parts of the world owing toenlarged dissolution features that enhance porosity and interconnectivity. To better understand the variationsof pore space in different karst aquifers, image and geospatial analyses are used to analyze pore attributes(i.e., pore area and perimeter) in images of vuggy aquifers. Pore geometry and 2D porosity derivedfrom images of the moldic Castle Hayne and vuggy Biscayne aquifers are analyzed at three scales of observation:borehole televiewer, core and thin-section. The Castle Hayne and Biscayne aquifers are the foci of thisstudy because the pore spaces that control the hydrologic properties in each of these aquifers are markedlydifferent even though both of these carbonate reservoirs are prolific aquifers. Assessments of pore area,perimeter and shape index (a measure of shape complexity) indicate that pore geometries and pore complexitiesvary as a function pore type and scale of observation. For each aquifer type, the areas, perimetersand complexities of pores are higher at the larger scale of observation (e.g., borehole) than the smallerscale of observation (e.g., thin section). When the complexity of the moldic pores is compared to the complexityof vuggy pores, the results indicate that moldic pores are generally more complex than vuggy poresat the same scale of observation. Whereas estimates of 2D porosity from the borehole televiewer image ofthe vuggy aquifer are higher than those derived from the moldic aquifer, the range of 2D porosities is largerin core and thin section images for the vuggy aquifer than themoldic aquifer. A model for the development ofpores is presented that suggests that the coalescence of small pores with simple shapes leads to the growth oflarger pores with more complex shapes. The model suggests that the younger Biscayne aquifer is a moremature karst than the Castle Hayne aquifer.


Characterisation and modelling of conduit restricted karst aquifers – Example of the Auja spring, Jordan Valley, 2014, Schmidta Sebastian, Geyera Tobias, Guttmanb Joseph, Mareic Amer, Riesd Fabian, Sauter Martin

The conduit system of mature karstified carbonate aquifers is typically characterised by a high hydraulic conductivity and does not impose a major flow constriction on catchment discharge. As a result, discharge at karst springs is usually flashy and displays pronounced peaks following recharge events. In contrast, some karst springs reported in literature display a discharge maximum, attributed to reaching the finite discharge capacity of the conduit system (flow threshold). This phenomenon also often leads to a non-standard recession behaviour, a so called “convex recession”, i.e. an increase in the recession coefficient during flow recession, which in turn might be used as an indicator for conduit restricted aquifers. The main objective of the study is the characterisation and modelling of those hydrogeologically challenging aquifers. The applied approach consists of a combination of hydrometric monitoring, a spring hydrograph recession and event analysis, as well as the setup and calibration of a non-linear reservoir model. It is demonstrated for the Auja spring, the largest freshwater spring in the Lower Jordan Valley. The semi-arid environment with its short but intensive precipitation events and an extended dry season leads to sharp input signals and undisturbed recession periods. The spring displays complex recession behaviour, exhibiting exponential (coefficient α) and linear (coefficient β) recession periods. Numerous different recession coefficients α were observed: ∼0.2 to 0.8 d−1 (presumably main conduit system), 0.004 d−1 (fractured matrix), 0.0009 d−1 (plateau caused by flow threshold being exceeded), plus many intermediate values. The reasons for this observed behaviour are the outflow threshold at 0.47 m3 s−1 and a variable conduit–matrix cross-flow in the aquifer. Despite system complexity, and hence the necessity of incorporating features such as a flow threshold, conduit–matrix cross-flow, and a spatially variable soil/epikarst field capacity, the developed reservoir model is regarded as relatively simplistic. As a number of required parameters were calculated from the hydrogeological analysis of the system, it requires only six calibration parameters and performs well for the highly variable flow conditions observed. Calculated groundwater recharge in this semi-arid environment displays high interannual variability. For example, during the 45-year simulation period, only five wet winter seasons account for 33% of the total cumulative groundwater recharge.


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