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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 finite difference method is a numerical method used to approximate the solution of partial differential equations [16].?

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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 distributions (Keyword) returned 53 results for the whole karstbase:
Showing 1 to 15 of 53
Present-Day Cave Beetle Fauna in Australia A Pointer to Past Climatic Change, 1965, Moore, B. P.

Beetles form an important element of life in caves, where they provide some of the most spectacular examples of adaptation to the environment. The troglobic forms are of greatest interest from the zoogeographical point of view and their present distributions, which are largely limited to the temperate regions of the world, appear to have been determined by the glaciations and later climatic changes of the Quaternary. Troglophiles, which are much more widespread, show little adaptation and are almost certainly recently evolved cavernicoles.

On some cave Collembola of Romania, 1968, Gruia Magdalena
An important collection of Collembola from Romania contained six species. One of them is new; Onychiurus orghidani n.sp. found in one cave of Oltenia. The presence of Onychiurus boldorii Denis in Romania is reported for the first time, and the discovery of a large number of Beckerella spelaea Ionesco made it possible to place this species in the genus Xenylla. Finally, additions are made to the known geographic distributions of Mesachorutes ojcoviensis Stach and Lepidocyrtus serbicus Denis.

On some cave Collembola of Romania, 1968, Gruia Magdalena
An important collection of Collembola from Romania contained six species. One of them is new; Onychiurus orghidani n.sp. found in one cave of Oltenia. The presence of Onychiurus boldorii Denis in Romania is reported for the first time, and the discovery of a large number of Beckerella spelaea Ionesco made it possible to place this species in the genus Xenylla. Finally, additions are made to the known geographic distributions of Mesachorutes ojcoviensis Stach and Lepidocyrtus serbicus Denis.

Geomorphology of the North Karst, South Nahanni River Region, Northwest Territories, Canada, PhD Thesis, 1976, Brook, George Albert,

First investigated on the ground in June 1972, the Nahanni karst of northern Canada is the most complex karst terrain yet reported from high latitudes. It is centered at 61°28' N, longitude 124°05' W and lies within the zone of discontinuous permafrost. Mean annual temperature is 24°F and mean total precipitation 22.3 inches. Principal karst forms are fracture-located karst streets and irregularly-shaped closed depression called karst platea which may be up to 600 feet in depth. Platea often contain karst towers which are residuals of wall recession. Vertical-walled pond dolines up to 120 feet deep are common in bare karst areas while subjacent karst collapse, subsidence and suffosion depressions occur on marginal shale- and drift-mantled surfaces. Three small poljes have been identified, two produced entirely by solution, the other a structural form. These are periodically inundated. There are several peripheral fluvial canyons up to 3,000 feet deep that are blocked by glacial drift and which presently drain underground. Similarity in the hydrogeological properties of Nahanni Formation limestones at a variety of scales has led to the development of morphologically-identical karst forms which range in size from inches up to hundreds of feet. Furthermore, many of these landforms are part of a developmental sequence that at one scale links vertical-walled dolines, karst streets, platea and poljes; and at another links solution pits, grikes and joint hollows on limestone pavements. The evidence suggests that poljes form by the coalescence of dolines and uvalas just as Cvijic suggested in 1918. In attempting to explain the almost "tropical" nature of the sub-arctic Nahanni karst landform assemblage, a number of facts are of importance.
(a) The Nahanni Formation limestones have been highly warped and intensively fractures during the past one million years. Open fractures have encouraged karstification by allowing easy movement of water underground. Warping has provided the relief necessary for the development of solutional forms with a distinct vertical component.
(b) The karst can not be considered relict because it was glaciated during the Pleistocene. In addition the hydrological activity in it today is comparable with that in many humid tropical karst areas.
(c) Solutional denudation rates governed by aspects of surficial and bedrock geology may in some localized areas be equivalent to rates in humid tropical carbonate regions.
(d) At present rates, the most highly developed forms could have been produced within the last 200,000 years and because there is evidence to indicate that the karst may not have been glaciated for up to 250,000 years, such a period has been available for solutional development.
Because the Nahanni region has not been glaciated for an extremely long period, it may be one of only a few high-latitude carbonate terrains that have had time to develop fully. Its very existence questions the validity of the concept that the intensity and direction of karst development is climate-controlled. In the Nahanni at least, the structural and lithological properties of the host limestone appear to have been of greater importance. The labyrinth karst type present in regions of humid-tropical to sub-arctic climate, is an outstanding example of a structurally-controlled karst landscape. It may well be that the same controls also influence the distributions of other karst types.

Variation among populations of the yroglobitic Amphipod Crustacean Crangonyx Antennatus Packard (Crangonyctidae) living in different habitats Il. Population distribution., 1982, Dickson Gary W.
Population densities and factors affecting the distribution of the troglobitic (i.e., obligatory cavernicole) amphipod Crangonyx antennatus were examined in two distinct aquatic habitats. Observations were made seasonally for one year in six Lee Co., Virginia (U.S.A.) caves, three with mud-bottom pools and three with gravel-bottom streams. Pool habitats were found to contain greater C. antennatus densities than stream habitats, while the highest seasonal densities were recorded in August. Availability of food is considered to be the major factor allowing these increased population densities. The population distribution of C. antennatus was not found to be related to current velocity, water depth, macro-detrital food sources or isopods densities in both pool and stream habitats. The distribution of C. antennatus was observed to be related to substrate type. Substrate selection appeared to be passive in five of the amphipod populations, while in one cave, substrate selection may be influenced by competitive interactions. The fact that population distributions were not related to environmental parameters which differ markedly between habitats indicates that this troglobitic species retains ecological flexibility.

Palaeoenvironment of lateritic bauxites with vertical and lateral differentiation, 1983, Valeton Ida,
Formation of lateritic bauxites of the type described in this paper occurs world-wide in Cretaceous and Tertiary coastal plains. The bauxites form elongate belts, sometimes hundreds of kilometres long, parallel to Lower Tertiary shorelines in India and South America and their distribution is not related to a particular mineralogical composition of the parent rock. The lateral movement of the major elements Al, Si, Fe, Ti is dependent on a high level and flow of groundwater. Varying efficiency of subsurface drainage produces lateral facies variations. Interfingering of marine and continental facies indicate a sea-land transition zone where the type of sediments also varies with minor tectonic movements or sea-level changes. A typical sediment association is found in India, Africa, South and North America. It consists of (i) red beds rich in detrital and dissolved material of reworked laterites, (ii) lacustrine sediments and hypersaline precipitates, (iii) lignites intercalated with marine clays, layers of siderite, pyrite, marcasite and jarosite, and (iv) marine chemical sediments rich in oolitic iron ores or glauconite. A model is developed to account for element distributions in lateritic bauxites in terms of groundwater levels and flow. Finally it is shown that many high-level bauxites are formed in coastal plains and that they are subsequently uplifted to their present altitude

A comparison of sinkhole depth frequency distributions in temperate and tropical karst regions, 1984, Troester J. W. , White E. L. , White W. B.

Genetic analysis of evolutionary processes, 1987, Wilkens Horst
Epigean and cave populations of A. fasciatus (Characidae, Pisces) differ in a series of morphological physiological, and ethological features. The interfertility of these populations made possible a genetic analysis of organs characteristic of interspecific divergence. The study of the regressive organs "eye" and "melanophore system" on the one hand and that of the constructively improved "gustatory equipment and feeding behaviour" on the other yielded identical principles of genetic manifestation: (1) All features have a polygenic basis with an at least di- to hexahybrid inheritance. (2) All polygenes have the same amount of expressivity. (3) After recombination of a minimum number of genes, discontinuous distributions (threshold effects) develop. (4) All features are independently inherited. (5) The genes responsible for a feature are unspecific. In the case of the eye this means that no "lens-" or "retinagenes" are analyzed; due to developmentally physiological interdependence within complex structures, only so-called "eye-genes" have as yet been described. Because of the developmentally physiological interdependence of complex organs, the process of reduction proceeds as a diminution in size, that of constructive evolution as enlargement. In both cases different allometric correlations of the single structures can be found. The convergent reduction of eyes in cave animals is caused by the loss of stabilizing selection which normally keeps the eye in its appropriate adapted form. It is not directional selection pressure, like f. ex. energy economy, but mutation pressure that causes eye reduction. By this, random mutations, which are mostly of deleterious character, are accumulated. The principles of regressive evolution are not restricted to the development of cave species. The absence of stabilizing selection regularly occurs during transitional evolutionary phases. These are f. ex. initial stages of speciation which may be observed when biotopes with little or no interspecific competition are colonized by an invader. Genotypic and phenotypic variability now arise and equilibria become punctuated, because stabilizing selection for a specific ecological niche which has once been acquired by the invading species is no longer acting. Examples include the evolution of species flocks in geologically young lakes or oceanic islands. Rapidly increasing variability now secondarily provides the material for directional selection which radiates such species into vacant niches. Genetic threshold effects as described above may accelerate this process. Variability will finally become lower again under the influence of inter- and intraspecific competition. A new equilibrium is attained.

Caesium-137 and Caesium-134 levels in soil in a tea plantation in Turkey after the chernobyl accident, 1989, Yesin T. , Cakir N. ,
Gamma-ray scintillation spectrometry has been used to measure the 137Cs and 134Cs levels and depth distributions in soil of a tea plantation in the Eastern Black Sea region in Turkey. Soil samples were collected in November 1987. The depth distribution was found to be exponential with [alpha] = 0.16 cm-1 and the exposure rate arising therefrom is calculated as 17.46 [mu]R/h over the ground surface

Chemical hydrogeology in natural and contaminated environments, 1989, Back W, Baedecker Mj,
Chemical hydrogeology, including organic and inorganic aspects, has contributed to an increased understanding of groundwater flow systems, geologic processes, and stressed environments. Most of the basic principles of inorganic-chemical hydrogeology were first established by investigations of organic-free, regional-scale systems for which simplifying assumptions could be made. The problems of groundwater contamination are causing a shift of emphasis to microscale systems that are dominated by organic-chemical reactions and that are providing an impetus for the study of naturally occurring and manmade organic material. Along with the decrease in scale, physical and chemical heterogeneity become major controls.Current investigations and those selected from the literature demonstrate that heterogeneity increases in importance as the study site decreases from regional-scale to macroscale to microscale. Increased understanding of regional-scale flow systems is demonstrated by selection of investigations of carbonate and volcanic aquifers to show how application of present-day concepts and techniques can identify controlling chemical reactions and determine their rates; identify groundwater flow paths and determine flow velocity; and determine aquifer characteristics. The role of chemical hydrogeology in understanding geologic processes of macroscale systems is exemplified by selection of investigations in coastal aquifers. Phenomena associated with the mixing zone generated by encroaching sea water include an increase in heterogeneity of permeability, diagenesis of minerals, and formation of geomorphic features, such as caves, lagoons, and bays. Ore deposits of manganese and uranium, along with a simulation model of ore-forming fluids, demonstrate the influence of heterogeneity and of organic compounds on geochemical reactions associated with genesis of mineral deposits. In microscale environments, importance of heterogeneity and consequences of organic reactions in determining the distributions and concentrations cf. constituents are provided by several studies, including infiltration of sewage effluent and migration of creosote in coastal plain aquifers. These studies show that heterogeneity and the dominance of organically controlled reactions greatly increase the complexity of investigations

Coastal karst aquifers have highly variable distributions of porosity and permeability. The ability to assess the volume of aquifer occupied by freshwater in coastal karst aquifers is limited by both the lack of understanding of the effect that regions of cavernous porosity and permeability have on the configuration of the saline-freshwater mixing zone and by the limited knowledge of the location of the cavernous regions. A dual-density ground-water flow and solute transport model was used to explore the effect that the depth, lateral extent, and proximity to the coast of zones of high porosity and permeability has on the configuration of the saline-freshwater mixing zone. These aquifer heterogeneities tend to shift the mixing zone upward relative to the position it would have in aquifers with homogeneous porosity and permeability, Zones of high porosity and permeability located at positions shallow in the aquifer or nearer to the coast had the greatest effect. In fact, for the conditions modeled, position was more important in modifying the configuration of the mixing zone than was changing the ratio of the intrinsic permeability of the cavernous zone to the aquifer matrix from 100 to 1000. Modeling results show that ground-water flow is concentrated into the zones of high porosity and permeability and that flow configuration results in steep salinity gradients with depth, Field observations of the location of the halocline and of step changes in ground-water composition coincident with regions of cavernous porosity in coastal karst aquifers corroborate the model results, In a coastal setting with saline water intruding into an aquifer, the effect of cavernous porosity and associated high permeability is to decrease the volume of aquifer in which freshwater occurs by a greater degree than would occur in an aquifer with homogeneous porosity and permeability

Risk assessment methodology for karst aquifers .2. Solute-transport modeling, 1997, 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

Geochemical patterns in soils of the karst region, Croatia, 1997, Prohic E. , Hausberger G. , Davis J. C. ,
Soil samples were collected at 420 locations in a 5-km grid pattern in the Istria and Gorski Kotar areas of Croatia, and on the Croatian islands of Cres, Rab and Krk, in order to relate geochemical variation in the soils to underlying differences in geology, bedrock lithology, soil type, environment and natural versus anthropogenic influences. Specific objectives included assessment of possible agricultural and industrial sources of contamination, especially from airborne effluent emitted by a local power plant. The study also tested the adequacy of a fixed-depth soil sampling procedure developed for meager karstic soils. Although 40 geochemical variables were analyzed, only 15 elements and 5 radionuclides are common to all the sample locations. These elements can be divided into three groups: (1) those of mostly anthropogenic origin - Pb, V, Cu and Cr; (2) those of mixed origin - radionuclides and Zn; and (3) those of mostly geogene origin - Ba, Sr, Ti, Al, Na, Ca, Mg, Fe, Mn, Ni and Co. Variation in Pb shows a strong correlation with the pattern of road traffic in Istria. The distributions of Ca, Na and Mg in the flysch basins of southern Istria and Slovenia are clearly distinguishable from the distributions of these elements in the surrounding carbonate terrains, a consequence of differences in bedrock permeability, type of drainage and pH. The spatial pattern of Cs-137 from the Chernobyl nuclear power plant accident reflects almost exclusively the precipitation in Istria during the days immediately after the explosion. (C) 1997 Elsevier Science B.V

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.

A Summary of Diversity and Distribution of the Obligate Cave-inhabiting Faunas of the United States and CanadaStewart, 1998, Peck, S. B.
A summary is given of families, genera, species numbers, and state distributions of the obligate subterranean (cave and groundwater) faunas of the contiguous United States and Canada. A total of 425 aquatic and 928 terrestrial species (1353 species in all) is now known. Total genus level diversity is greatest (in descending order) in the states of Texas, Alabama, Kentucky, Tennessee and Virginia. This genus and species richness is vulnerable to a variety of land use and pollution problems

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