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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 moulin is the french word for 'mil', moulin has been used to describe partially dissolutional, partially scoured pockets cut in rock, particularly the potholes formed in the beds of surface and underground streams. in some areas sinkholes in the surface of glaciers, which may provide access to glacier caves, are also referred to as moulins [9].?

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

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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.
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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 size distribution (Keyword) returned 14 results for the whole karstbase:
Pervasive early- to late-stage dolomitization of Lower Ordovician Ellenburger Group carbonates in the deep Permian Basin of west Texas and southeastern New Mexico is recorded in core samples having present-day burial depths of 1.5-7.0 km. Seven dolomite-rock textures are recognized and classified according to crystal-size distribution and crystal-boundary shape. Unimodal and polymodal planar-s (subhedral) mosaic dolomite is the most widespread type, and it replaced allochems and matrix or occurs as void-filling cement. Planar-e (euhedral) dolomite crystals line pore spaces and/or fractures, or form mosaics of medium to coarse euhedral crystals. This kind of occurrence relates to significant intercrystalline porosity. Non-planar-a (anhedral) dolomite replaced a precursor limestone/dolostone only in zones that are characterized by original high porosity and permeability. Non-planar dolomite cement (saddle dolomite) is the latest generation and is responsible for occlusion of fractures and pore space. Dolomitization is closely associated with the development of secondary porosity; dolomitization pre-and post-dates dissolution and corrosion and no secondary porosity generation is present in the associated limestones. The most common porosity types are non-fabric selective moldic and vuggy porosity and intercrystalline porosity. Up to 12% effective porosity is recorded in the deep (6477 m) Delaware basin. These porous zones are characterized by late-diagenetic coarse-crystalline dolomite, whereas the non-porous intervals are composed of dense mosaics of early-diagenetic dolomites. The distribution of dolomite rock textures indicates that porous zones were preserved as limestone until late in the diagenetic history, and were then subjected to late-stage dolomitization in a deep burial environment, resulting in coarse-crystalline porous dolomites. In addition to karst horizons at the top of the Ellenburger Group, exploration for Ellenburger Group reservoirs should consider the presence of such porous zones within other Ellenburger Group dolomites

The Lower Triassic Montney Formation, west-central Alberta, 1997, 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

Particle size distributions in waters from a karstic aquifer: from particles to colloids, 1997, Atteia O, Kozel R,
Waters from the surface hydrologic network and the spring of a karstic aquifer in Switzerland were sampled to analyse their colloidal content. The measurements were done weekly with a single particle counter and were verified by other techniques. The particle size distribution (PSD) was modelled in two portions, below and above 5 mu m, using two types of equation: a power law (Pareto distribution) and an exponential law. The model results matched well with the entire PSD data set by varying the parameter values. The parameters obtained from fitting the measured PSD curves were then interpreted in relation to environmental factors. It appears that the two parts of the curves vary independently. The first part of the PSD curve, relating to the smallest particles, is dependent on the pH value of the spring or the temperature of the surface brook. In contrast, the second part of the curve depends mostly on the spring discharge volume. During high flow events, the major effect of the discharge on particle size occurs during the rising limb of the hydrograph, interpreted as clays deposited in the aquifer and resuspended due to high water velocity. The contrasted behaviour of the two parts of the PSD curves suggested that the break point in the curves represents the limit between colloidal and particulate behaviour. Knowing these dependencies, and the characteristics of the particulate matter, allowed the estimation of the role of the colloids in contaminant transport. Large fluxes of suspended matter, specific to karstic aquifers, demonstrate the critical role of colloids in contaminant transport, which is markedly different from what typically occurs in porous media.

Evolution of size distributions of natural particles during aggregation: modelling versus field results, 1998, Atteia O,
In this paper a discretized model simulating aggregation of size distributions jointly with sedimentation and transport is presented. A review of the current theory provides some helpful hints about the relative importance of each aggregation process, i.e. Brownian motion, shear flow and differential sedimentation, which are tested by using collision efficiency factors. The novel aspect of the model arises from the use of a varying mean particle diameter in each size class. This allows both non-steady-state and steady-state calculations and free choice of size classes. A comparison with a classical approach shows the exactitude of the results and the improvment obtained for several cases. The simulations gave a family of curves characterized by three parts corresponding to peri-, and orthokinetic aggregation and to sedimentation. The role of collision effciency is crucial in the relative extent of each part of the size distribution. The comparison with a series of data from a karst spring showed that the model was able to fit most of the particle size distributions using significant values of each parameter. This allowed information about particle aggregation and transport within a non-accessible aquifer to be inferred.

Particle size distributions in waters from a karstic aquifer: from particles to colloids., 1998, Atteia O. , Kozel R.

Muddy waters: temporal variation in sediment discharging from a karst spring, 1999, Mahler B. J. , Lynch F. L. ,
Karst aquifers are capable of transporting and discharging large quantities of suspended sediment, which can have an important impact on water quality. Here we present the results of intensive monitoring of sediment discharging from a karst spring in response to two storm events, one following a wet season and the other following a dry season; we describe temporal changes in total suspended solids (TSS), mineralogy, and particle size distribution. Peak concentrations of suspended sediment coincided with changes in aqueous chemistry indicating arrival of surface water, suggesting that much of the discharging sediment had an allochthonous origin. Concentrations of suspended sediment peaked 14-16 h after rainfall, and the bulk of the sediment (approximately 1 metric ton in response to each storm) discharged within 24 h after rainfall. Filtered material included brightly colored fibers and organic matter. Suspended sediments consisted of dolomite, calcite, quartz, and clay. Proportions of each mineral constituent changed as the aquifer response to the storm progressed, indicating varying input from different sediment sources. The hydraulic response of the aquifer to precipitation was well described by changes in parameters obtained from the particle size distribution function, and corresponded to changes seen in TSS and mineralogy. Differences between storms in the quantity and mineralogy of sediment transported suggest that seasonal effects on surface sediment supply may be important. The quantity of sediment discharging and its potential to sorb and transport contaminants indicates that a mobile solid phase should be included in contaminant monitoring and contaminant transport models of karst. Temporal changes in sediment quantity and characteristics and differences between responses to the two storms, however, demonstrate that the process is not easily generalized. (C) 1999 Elsevier Science B.V. All rights reserved

Transport of suspended solids from a karstic to an alluvial aquifer: the role of the karst/alluvium interface, 2002, Massei N. , Lacroix M. , Wang H. Q. , Mahler B. J. , Dupont J. P. ,
This study focuses on the coupled transport of dissolved constituents and particulates, from their infiltration on a Karst plateau to their discharge from a karst spring and their arrival at a well in an alluvial plain, Particulate markers were identified and the transport of solids was characterised in situ in porous and karstic media, based on particle size analyses, SEM, and traces. Transport from the sinkhole to the spring appeared to be dominated by flow through karst: particulate transport was apparently conservative between the two sites, and there was little difference in the overall character of the particle size distribution of the particulates infiltrating the sinkhole and of those discharging from the spring. Qualitatively, the mineralogy of the infiltrating and discharging material was similar, although at the spring an autochthonous contribution from die aquifer was noted (chalk particles eroded from the parent rock by weathering). In contrast, transport between the spring and the well appears to be affected by the overlying alluvium: particles in the water from the well, showed evidence of considerable size-sorting. Additionally, SEM images of the well samples showed the presence of particles originating from the overlying alluvial system; these particles were not found in samples from the sinkhole or the spring. The differences between the particulates discharging from the spring and the well indicate that the water pumped from the alluvial plain is coming from the Karst aquifer via the very transmissive, complex geologic interface between the underlying chalk formation and the gravel at the base of the overlying alluvial system. (C) 2002 Elsevier Science B.V. All rights reserved

Soil types and eolian dust in high-mountainous karst of the Northern Calcareous Alps (Zugspitzplatt, Wetterstein Mountains, Germany), 2003, Kufmann C. ,
This, study deals with the soil formation on pure limestone in the high-mountainous karst of Wetterstein Mountains (Northern Calcareous Alps). The study area in detail covers the alpine (2000 to 2350 in) and the subnivale zone (2350 to 2600 in) of Zugspitzplatt, a tertiary paleosurface situated next to the highest summit of Germany (Zugspitze 2963 in). The formation of autochthonous soils is determined by the following parameters: uniform geology and geochemistry of Triassic limestone (CaCO3 MgCO3 greater than or equal to 98%), variable substrata (solid rock, debris, local moraine), hypsometric pattern of vegetation modified by microclimate and aspect, variety of micro-environments in karst relief. In the subnivale zone, only leptosols (lithic, skeletic) and regosols (calcaric, humic) occur, whereas in the alpine zone different stages of folic histosols and rendzic leptosols prevail due to the diversity of vegetation. The purity of limestone prevents a distinct contribution of residues to soil formation. Instead of expected A-B-C profiles, the residues are mixed with organic matter of folic horizons (O-OB-C). Only in karst depressions or on local moraines small Bt horizons (2 to 5 cm) occur. They mark a developed stage of folic histosol (O-OB-Bt-C) representing the climax of autochthonous mineral soil genesis in the study area. Special features are brown deposits (mean thickness 30 cm) covering large parts of the alpine zone. On the basis of mineralogical (X-ray diffraction, heavy minerals) and pedological data (grain size, soil chemistry), eolian origin is indicated. The resulting soils are classified as loess loam-like cambisols (Ah-Bw-2(Bt)-2C) and are related to late glacial loess deposition (Egesen-Stade of Younger Dryas). The abundance of mica and silt in the surface layers and the grain size distribution of snow dust samples prove that dust influx by southerly winds is still continuing. The major sources for both late glacial and present-day dust are magmatic and metamorphic rock formations of the Central Alps. Additionally, local dust transport from adjacent outcrops of Jurassic and Lower Cretaceous sediments is evident. (C) 2003 Elsevier Science B.V. All rights reserved

Assessing subsoil permeability for groundwater vulnerability, 2003, Swartz M. , Misstear B. D. R. , Daly D. , Farrell E. R. ,
Groundwater vulnerability assessment is a key element of any groundwater protection scheme. In Ireland, groundwater vulnerability is determined mainly according to the thickness and permeability of the subsoils (glacial tills and other superficial deposits). The relative permeabilities of the subsoils are assessed qualitatively as high, moderate or low. To improve the robustness of the groundwater protection scheme, research was carried out into subsoil properties with the aims of refining the permeability ratings, and of improving the way in which subsoil permeability classes are assigned. This research focused on subsoils in the low and moderate permeability categories, mainly tills. Important issues investigated were the relationship between permeability and the grain size distribution of the subsoil, description of subsoils for permeability classification, correlation between permeability and indicators of aquifer recharge, and suitable field and laboratory methods for measuring subsoil permeability. A standard system for describing subsoils was selected, namely BS5930:1999, the choice being influenced by the familiarity of this system among the main users of the vulnerability maps. Analysis of subsoil field descriptions and grain size data indicate that those samples identified as CLAY' on the basis of BS 5930 correspond to the low permeability category, and tend to have more than 13% clay size particles. The permeability values obtained from each method are compared and indicate that the numerical boundary between moderate and low permeability lies in the region of 10-9 m/s. Differences between the results from laboratory and various field permeability test methods can be explained by differences in scale and by the presence of discontinuities. The research was successful in refining the permeability ratings and thereby in making the vulnerability maps more defensible against possible challenges. This research has improved the way permeability maps are produced in Ireland, and may prove useful in other countries where permeability data are scarce and mapping relies largely on field assessment of subsoils

Heterogeneity of parent rocks and its constraints on geochemical criteria in weathering crusts of carbonate rocks, 2004, Wang S. J. , Feng Z. G. ,
Owing to the low contents of their acid-insoluble components, carbonate rocks tend to decrease sharply in volume in association with the formation of weathering crust. The formation of a 1 m-thick weathering crust would usually consume more than ten meters to several tens of meters of thickness of parent rocks. The knowledge of how to identify the homogeneity of parent rocks is essential to understand the formation mechanism of weathering crust in karst regions. especially that of thick-layered red weathering crust. In this work the grain-size analyses have demonstrated that the three profiles studied are the residual weathering crust of carbonate rocks and further showed that there objectively exists the, heterogeneity of parent rocks in the three studied weathering crusts. The heterogeneity of parent rocks can also be. reflected in geochemical parameters of major elements, just as the characteristics of frequency plot of pain-size distribution. Conservative trace element ratios Zr/Hf and Nb/Ta are proven to be unsuitable for tracing the heterogeneity of parent rocks of weathering crust, but its geochemical mechanism is unclear. The authors strongly suggest in this paper that the identification of the homogeneity of parent rocks of weathering crust in karst regions is of prime necessity

Distribution, morphology, and origins of Martian pit crater chains, 2004, Wyrick D. , Ferrill D. A. , Morris A. P. , Colton S. L. , Sims D. W. ,
Pit craters are circular to elliptical depressions found in alignments (chains), which in many cases coalesce into linear troughs. They are common on the surface of Mars and similar to features observed on Earth and other terrestrial bodies. Pit craters lack an elevated rim, ejecta deposits, or lava flows that are associated with impact craters or calderas. It is generally agreed that the pits are formed by collapse into a subsurface cavity or explosive eruption. Hypotheses regarding the formation of pit crater chains require development of a substantial subsurface void to accommodate collapse of the overlying material. Suggested mechanisms of formation include: collapsed lava tubes, dike swarms, collapsed magma chamber, substrate dissolution ( analogous to terrestrial karst), fissuring beneath loose material, and dilational faulting. The research described here is intended to constrain current interpretations of pit crater chain formation by analyzing their distribution and morphology. The western hemisphere of Mars was systematically mapped using Mars Orbiter Camera (MOC) images to generate ArcView(TM) Geographic Information System (GIS) coverages. All visible pit crater chains were mapped, including their orientations and associations with other structures. We found that pit chains commonly occur in areas that show regional extension or local fissuring. There is a strong correlation between pit chains and fault-bounded grabens. Frequently, there are transitions along strike from ( 1) visible faulting to ( 2) faults and pits to ( 3) pits alone. We performed a detailed quantitative analysis of pit crater morphology using MOC narrow angle images, Thermal Emission Imaging System (THEMIS) visual images, and Mars Orbiter Laser Altimeter (MOLA) data. This allowed us to determine a pattern of pit chain evolution and calculate pit depth, slope, and volume. Volumes of approximately 150 pits from five areas were calculated to determine volume size distribution and regional trends. The information collected in the study was then compared with non-Martian examples of pit chains and physical analog models. We evaluated the various mechanisms for pit chain development based on the data collected and conclude that dilational normal faulting and sub-vertical fissuring provide the simplest and most comprehensive mechanisms to explain the regional associations, detailed geometry, and progression of pit chain development

A pipe-based, first approach to modeling closed conduit flow in caves, 2004, Springer Gregory S. ,
A closed conduit model is constructed for a discrete cave segment using the energy equation and the assumption that energy losses in the segment are generated by large-scale flow separation associated with expansions and bends. As employed, the model uses paleostage indicators and passage geometry to estimate total head loss across the study reach. Channel roughness is estimated using pipe-based equations and a skin friction factor estimated from secondary means. Discharge is varied in the model until calculated head loss matches observed head loss. The model is employed to estimate discharge for a flood recorded in Buckeye Creek Cave, West Virginia as high water marks consisting of silt lines. Under varying assumptions, the model yields paleodischarges in the range of 22-29 m3 s-1. Shear stress values calculated using model output are in general agreement with the size distribution of gravel on the stream bed and shear stress values are relatively insensitive to changes in discharge. The apparent friction factor for the study reach is estimated to be in the range of 0.4-0.7, which is in general agreement with previous studies of large conduits. The model is applicable to similar cave reaches, but requires further testing and validation because so little is known about conduit flow in karst

Percolation and Particle Transport in the Unsaturated Zone of a Karst Aquifer, 2009, Pronk M. , Goldscheider N. , Zopfi J. , Zwahlen F.

Recharge and contamination of karst aquifers often occur via the unsaturated zone, but the functioning of this zone has not yet been fully understood. Therefore, irrigation and tracer experiments, along with monitoring of rainfall events, were used to examine water percolation and the transport of solutes, particles, and fecal bacteria between the land surface and a water outlet into a shallow cave. Monitored parameters included discharge, electrical conductivity, temperature, organic carbon, turbidity, particle-size distribution (PSD), fecal indicator bacteria, chloride, bromide, and uranine. Percolation following rainfall or irrigation can be subdivided into a lag phase (no response at the outlet), a piston-flow phase (release of epikarst storage water by pressure transfer), and a mixed-flow phase (increasing contribution of freshly infiltrated water), starting between 20 min and a few hours after the start of recharge event. Concerning particle and bacteria transport, results demonstrate that (1) a first turbidity signal occurs during increasing discharge due to remobilization of particles from fractures (pulse-through turbidity); (2) a second turbidity signal is caused by direct particle transfer from the soil (flow-through turbidity), often accompanied by high levels of fecal indicator bacteria, up to 17,000 Escherichia coli/100 mL; and (3) PSD allows differentiation between the two types of turbidity. A relative increase of fine particles (0.9 to 1.5 lm) coincides with microbial contamination. These findings help quantify water storage and percolation in the epikarst and better understand contaminant transport and attenuation. The use of PSD as ‘‘early-warning parameter’’ for microbial contamination in karst water is confirmed.

Temporal Stability of Cave Sediments, 2011, Peterson E. W. , Hughes K.

Sediments within cave systems have been examined concerning source, mineralogy, and transport potential. While sediments in the thalweg are very mobile, the entrainment potential of the sediment piles has not been examined. Over the course of nine months, sediment piles in a Missouri cave were sampled to determine the stability of the piles and of the sediment properties. Sediment cores were analyzed for dry bulk density (ρd), porosity (n), volumetric wetness (θ), organic content (O.C.), hydraulic conductivity (K), and sediment particle size distribution. Observational evidence, deposited sediment and deformation of previous sample holes, suggests that despite elevated flows, the sediment piles were not mobilized over the course of the nine months. Physical properties remained constant at each location, but varied among the various locations. Dry bulk density values ranged between 1.2 g/cm 3 to 1.5 g/cm 3 . Porosity values were 0.42 to 0.57. Volumetric wetness showed similar variation ranging from 0.38 to 0.53. Organic content had the highest variation among the parameters ranging from 1.24 percent at one site to 4.84 percent at another. Hydraulic conductivity ranged from 2.13×10 -7 m/s to 3.10×10 -7 m/s. 

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