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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. ...

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. ...

Speleology in Kazakhstan

Shakalov on 11 Jul, 2012
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 low flow is the lowest sustaining flow during base runoff conditions of a river [16].?

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Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
Engineering challenges in Karst, Stevanović, Zoran; Milanović, Petar
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Geochemical and mineralogical fingerprints to distinguish the exploited ferruginous mineralisations of Grotta della Monaca (Calabria, Italy), Dimuccio, L.A.; Rodrigues, N.; Larocca, F.; Pratas, J.; Amado, A.M.; Batista de Carvalho, L.A.
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
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Search in KarstBase

Your search for velocity (Keyword) returned 102 results for the whole karstbase:
Showing 1 to 15 of 102
Predicting travel times and transport characterization in karst conduits by analyzing tracer-breakthrough curves, , Morales Tomas, De Valderrama Inigo, Uriarte Jesus A. , Antiguedad Inaki, Olazar Martin,
SummaryThis paper analyzes data obtained in 26 tracer tests carried out in 11 karstic connections following solutional conduits in karst aquifers in the Basque Country. These conduits are preferential drainage pathways in these aquifers and so they confer a marked anisotropy and high vulnerability to them. Consequently, their consideration in protection and management studies and projects is a priority.The connections studied cover a wide hydrogeological spectrum (a wide range of sizes, slopes, geomorphic and hydrologic types) and the tests have been carried out at different hydrodynamic states. It is noteworthy that they all follow a similar trend, which has allowed for the development of a statistical approximation for the treatment of the whole information.Relationships have been established involving velocity, solute time of arrival, attenuation of peak concentration and time of passage of tracer cloud. These relationships are a valuable tool for management and supporting decision-making and allow for making estimates in connections in which the information available was scarce. This information is especially useful, given that the complexity of transport in karst conduits gives way to important deviations between real data (empirical observations) and the data obtained by simple approaches based on the Fickian-type diffusion equation

The Use of Titanium Tetrachloride In The Visualisation Of Air Movement In Caves, 1971, Halbert E. J. , Michie N. A.

The problems concerned with the visualisation of low-velocity air flow in caves are discussed. The behaviour of several chemical tracers in the Mammoth Cave, Jenolan, New South Wales, is described, in particular that of the compound titanium tetrachloride. A suitable method for the transport and use of this compound has been developed.


Deducing Flow Velocity in Cave Conduits from Scallops, 1974, Curl, Rane L.

Rapid groundwater flow in fissures in the chalk: an example from south Hampshire, 1974, Atkinson Tc, Smith Di,
Projected road improvements in south Hampshire included plans to dispose of surface drainage into soakaways to be sited near an area of swallow holes in the Chalk. An experiment was undertaken to establish if there was a direct connection between the swallow holes, located near the junction of the Chalk and the Lower Tertiary strata, and major springs used for water supply in the Havant area. As the swallow holes are dry except in periods of storm rainfall a tracer, the fluorescent dye Rhodamine WT, was injected together with a large volume of water into one of the swallow holes. Water samples were collected from the springs at Havant and analysed for Rhodamine WT using a Turner fluorometer. The tracer was found at both sets of springs sampled and the straight line velocity from input point to spring was in excess of 2 km per day. Computations based on the concentration of dye recovered from the springs show that in the event of a tanker spillage within the proposed drainage scheme severe contamination would be expected to occur at the springs. The experiment and the results obtained make it clear that extreme caution should be exercised to avoid contamination of fissure-flow within the Chalk aquifer

The role of groundwater in eutropication of a lake in glacial outwash terrain., 1976, Lee David Robert
The nutrient contribution of groundwater in glacial outwash terrain was evaluated at Lake Sallie in north-central U.S.A. (4646' N., 95 54' W.). Groundwater entering the lake was collected with seepage meters consisting of bottomless cylinders vented to a thin membrane bag. A theoretical flow net and comparison of nutrient concentrations in well and seepage water indicated that seepage meters can be used in high velocity discharge areas to obtain site-specific water samples of groundwater for nutrient analyses. Based on an average value of 0.25 mg/l PO4, groundwater inflow along an 800 km segment of shoreline transported 37 kg of phosphorus per year into the lake. Groundwater inflow was nitrate rich along shoreline adjacent so land used for agriculture and lakeside septic tanks, but there was no apparent pattern regarding land use and phosphorus content of groundwater inflow. A nearby eutrophic lake was a suspected source of phosphorus in groundwater inflow. Because surface flow has carried large quantities of nitrogen and phosphorus into this lake, its present eutrophic condition cannot be attributed to nutrient influx by groundwater. However, groundwater nutrient influx could be highly significant in other lakes where surface nutrient influx is small.

Fluoreszenzmikroskopische Untersuchung der Bakterienflora und Bestimmung ihrer heterotrophen Aktivitt in organisch belastetem und unbelastetem Grundwasser sandig-kiesiger Ablagerungen., 1981, Marxsen Jurgen
Bacteriological investigations were carried out in the groundwater of sandy and gravelly deposits of the river Fulda valley in an area named Johannesaue near the town Fulda (Hesse, Fed. Rep. of Germany). In January 1979 water samples were collected from 16 pumping tubes distributed in organically polluted and unpolluted areas. For characterizing the bacterial populations, methods used for surface waters were modified and, as far as the author is aware, these methods were used for the first time for investigations pertaining subterranean waters. The bacteria were counted by means of epifluorescence microscopy after staining the bacteria with the fluorochrome acridine orange. This technique renders possible the simultaneous registration of shape and size of bacteria. Parameters characterizing the heterotrophic bacterial activity were measured with 14C-labelled glucose. The number of bacteria in the groundwater collected through pumping tubes, varied from 1.4 to 11.3 million bacteria per ml. The relative glucose uptake potential vr, which was measured at one substrate concentration (600 microg glucose .1-1) where the maximum uptake velocity is almost reached, was 0.12; 0.74 microg glucose 1-1 .h-1. The corresponding specific potential was 0.02-0.18 microg glucose h-1 cell-1. The results agreed with the values of maximum uptake velocity Vmax which was measured at the same time in some of the groundwater samples. The data give first information about distribution of the number of bacteria and of heterotrophic bacterial activity in the groundwater of the investigation area. Relationships could be shown between the bacteriological parameters on the one hand and the concentration of oxygen and the values of COD measured with KMnO4 on the other hand.

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.

The hydraulics of conduit flow in carbonate aquifers., 1984, Gale S. J.

Analysis of the morphology of dissolution-bedform assemblages and hydraulically-transported sediments found within conduits in carbonate aquifers in North America and the British Isles has allowed the hydraulic conditions under which conduit flows occur to be established. Mean values of flow velocity, boundary-shear stress, conduit Reynolds number, conduit Froude number, boundary friction factor, boundary roughness and flow power have been calculated. The values obtained are in agreement with other evidence in the conduits and are comparable to those obtained from other, similar, hydraulic systems.


Dissolution kinetics of dolomite: effects of lithology and fluid flow velocity., 1985, Herman J. S. , White W. B.

Une marmite remarquable du trou qui Souffle (Vercors, France), 1987, Lismonde, B.
A REMARKABLE GIANT POT IN "TROU QUI SOUFFLE " (VERCORS, FRANCE) - In the cave of " Trou qui Souffle " (Maudre, Vercors), the SGCAF team of Grenoble has discovered a remarkable giant pot (5.4 m deep and 1.2 m diameter). His wall is covered with scallops, and thus, it is possible to determine the velocity field in the giant pot by means of the Curls law.

Les vagues d'rosion, 1987, Lismonde B. , Lagmani A.
CURRENT MARKINGS OR SCALLOPS - The scallops pattern on the wall of limestone cave result from the interaction of a soluble surface and a turbulent flow. The main results of Curl, particularly, the dependence of the velocity flow on the scallops length are presented.

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

Mesure de la propagation dune perturbation de pression au Trou qui Souffle (Maudre, Isre), 1993, Lismonde, B.
The Trou qui Souffle (Breathing Pot) is a cave in Vercors. There are three entrances, two of which are known and are situated 2 km apart. With one entrance rapidly obstructed, the effect upon the velocity of wind was measured at the other. The findings were a speed of about 100 m/s

MICROBIAL DECOMPOSITION OF ELM AND OAK LEAVES IN A KARST AQUIFER, 1993, Eichem Ac, Dodds Wk, Tate Cm, Edler C,
Dry Chinquapin oak (Quercus macrocarpa) and American elm (Ulmus americana) leaves were placed in four microcosms fed by groundwater springs to monitor changes in dry mass, ash-free dry mass, and microbial activity over a 35-day period. Oxygen microelectrodes were used to measure microbial activity and to estimate millimeter-scale heterogeneity in that activity. Oak leaves lost mass more slowly than elm leaves. Generally, there was a decrease in total dry weight over the first 14 days, after which total dry weight began to increase. However, there were consistent decreases in ash-free dry mass over the entire incubation period, suggesting that the material remaining after initial leaf decomposition trapped inorganic particles. Microbial activity was higher on elm leaves than on oak leaves, with peak activity occurring at 6 and 27 days, respectively. The level of oxygen saturation on the bottom surface of an elm leaf ranged between 0 and 75% within a 30-mm2 area. This spatial heterogeneity in O2 saturation disappeared when the water velocity increased from 0 to 6 cm s-1. Our results suggest that as leaves enter the groundwater, they decompose and provide substrate for microorganisms. The rate of decomposition depends on leaf type, small-scale variations in microbial activity, water velocity, and the length of submersion time. During the initial stages of decomposition, anoxic microzones are formed that could potentially be important to the biogeochemistry of the otherwise oxic aquifer

DIVERSITY - A NEW METHOD FOR EVALUATING SENSITIVITY OF GROUNDWATER TO CONTAMINATION, 1993, Ray J. A. , Odell P. W. ,
This study outlines an improved method, DIVERSITY, for delineating and rating groundwater sensitivity. It is an acronym for Dlspersion/VElocity-Rated SensitivITY, which is based on an assessment of three aquifer characteristics: recharge potential, flow velocity, and flow directions. The primary objective of this method is to produce sensitivity maps at the county or state scale that illustrate intrinsic potential for contamination of the uppermost aquifer. Such maps can be used for recognition of aquifer sensitivity and for protection of groundwater quality. We suggest that overriding factors that strongly affect one or more of the three basic aquifer characteristics may systematically elevate or lower the sensitivity rating. The basic method employs a three-step procedure: (1) Hydrogeologic settings are delineated on the basis of geology and groundwater recharge/discharge position within a terrane. (2) A sensitivity envelope or model for each setting is outlined on a three-component rating graph. (3) Sensitivity ratings derived from the envelope are extrapolated to hydrogeologic setting polygons utilizing overriding and key factors, when appropriate. The three-component sensitivity rating graph employs two logarithmic scales and a relative area scale on which measured and estimated values may be plotted. The flow velocity scale ranging from 0.01 to more than 10,000 m/d is the keystone of the rating graph. Whenever possible, actual time-of-travel values are plotted on the velocity scale to bracket the position of a sensitivity envelope. The DIVERSITY method was developed and tested for statewide use in Kentucky, but we believe it is also practical and applicable for use in almost any other area

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