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Enviroscan Ukrainian Institute of Speleology and Karstology

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Speleology in Kazakhstan

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

New publications on hypogene speleogenesis

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

The deepest terrestrial animal

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

Caves - landscapes without light

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

Did you know?

That stress, applied is the downward stress imposed at an aquifer boundary. it differs from effective stress in that it defines only the external stress tending to compact a deposit rather than the grain-to-grain stress at any depth within a compacting deposit [21].?

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.
See all featured articles
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 percolation. (Keyword) returned 7 results for the whole karstbase:
Diffuse flow and conduit flow in limestone terrain in the Mendip Hills, Somerset (Great Britain), 1977, Atkinson T. C.
The hydrogeology of the karstic Carboniferous Limestone is described. Water tracing has established recharge areas for fifteen major springs and water budgets confirm the size of the areas found. Groundwater flow occurs in two modes: turbulent conduit flow and diffuse Darcian flow in fine fractures. Recharge is 50% quickflow via caves and closed depressions and 50% slower percolation. Active storage in the diffuse component (S = 0.92%) is 30 times greater than in phreatic conduits. Diffuse hydraulic conductivity is 0.89 m day−1 and an average of 60?80% of groundwater is transmitted by conduits in this maturely karsted and steeply dipping aquifer.

Etude des circulations d'air dans la grotte de Niaux, 1983, Andrieux, C.
THE AIR MOVEMENTS IN THE grotte DE NIAUX. CONSEQUENCES - The present paper deals with air movements in the grotte de Niaux (Arige, France) during ten years (1971-1980). The data (observations, measurements) have been obtained, upon an average, each week; they relate to the direction of underground air movements, to the speed and to average air flow, which have been measured at some places, at cave entrances. The results show two types of air movements. In the first one, the gas exchanges between the cave and outside happen through the galleries and the known entrances and also through all the fractures of the carbonate rocks. When it occurs, the cave can be divided in three main parts, each one having their own characteristics. The second one is observed only during very rainy times; the whole cave is then subjected to air movement according to the "wind tube model". The air exchanges through the fractures are fixed by the percolation. The percolation zone is consequently submitted to diphasic water flow. Therefore, different models of air movements in caves must be considered. These data also show it is needful that the airflow should be measured to understand the climatic phenomena of the caves.

The role of the subcutaneous zone in karst hydrology, 1983, Williams Paul W. ,
The subcutaneous zone is the upper weathered layer of rock beneath the soil, but above the permanently saturated (phreatic) zone. It is of particular hydrological importance in karst because of its high secondary permeability, arising from the considerable chemical solution in this zone. However, corrosional enlargement of fissures diminishes with depth; thus permeability decreases in the same direction with the result that percolation is inhibited, except down widened master joints and faults. Storage of water consequently occurs in this zone, particularly after storms. The upper surface of this suspended saturated layer in the subcutaneous zone is defined by a perched water table, which slopes towards points of rapid vertical percolation. The potential induces lateral water movement converging on the most permeable areas such as beneath dolines. Leakage from the subcutaneous store sustains slow percolation in the vadose zone. Cross-correlation of rainfall with percolation rates in caves in New Mexico, U.S.A., and New Zealand reveal response lags of 2-14 weeks with no apparent relationship to depth below the surface. Other percolation sites show no correlation with rainfall; interpreted as being a consequence of considerable friction in tight fissure networks. The recognition of storage and rapid as well as very slow percolation from the subcutaneous zone requires re-interpretation of the components of hydrographs from karst springs and of some conceptual models of karst aquifers. The importance of subcutaneous storage in sustaining baseflow discharge at some sites must be recognised, as must the contribution of subcutaneous water to flood hydrographs. Methods of estimating the volumes of subcutaneous and phreatic components of karst-spring flood hydrographs are presented. The paper concludes with a discussion of the significance of subcutaneous hydrologic processes for an understanding of karst geomorphology. The desirability of explaining karst landform evolution in terms of hydrologic processes is stressed

Numerical multisource and multiscale imagery in the study of the topographic surface. Hydrogeological application in a karstic environment: Verneuil-sur-Avre (Perche, France), 1996, Sykioti O. , Deffontaines B. , Chorowicz J. , Obert D. , Demarsily G. , Lauverjat J. , Carvalho J. ,
We propose a new method revealing geological structures and their possible relationships with water percolation. It is based on a combination of (1) numerical analysis of the topography (satellite imagery Landsat TM, HCMM, SAR-ERS1; digital elevation model and derived data: drainage network, slope map, summit level surfaces...); (2) classic geological approach (field work, geological mapping, gravimetry); and (3) hydrogeological approach (piezometric map, tracer experiments). The superimposition of these data into a geocoded data base leads to the identification and the location of morphostructures (synthetic structural map). Field data and tracer experiments confirm the validity of the results. We propose to take into consideration the present day stress regime in order to define main orientations of open fractures. In conclusion, this method provides structural information allowing a better understanding of geometry in karstic aquifers

Recharge and aquifer response: Northern Guam Lens Aquifer, Guam, Mariana Islands, 2002, Jocson J. M. U. , Jenson J. W. , Contractor D. N. ,
The Northern Guam Lens Aquifer is an island karst aquifer in uplifted young, highly conductive limestone. Calculations of recharge based on differences between daily rainfall and daily pan evaporation suggest that the maximum annual mass of water delivered to the freshwater lens is about 67% of mean annual rainfall. Hydrographs of daily well-level responses plotted against daily rainfall indicate that the rate at which water is delivered to the lens is a function of rainfall intensity and the relative saturation of the vadose zone. Together, these variables determine the degree to which stormwater is shunted into fast flow through preferred pathways that bypass the bedrock matrix, rather than percolating slowly through the bedrock matrix. Data from the 40-year interval from 1956 to 1995 show that some 17% of rainfall on northern Guam arrives in small amounts (<0.6 cm/day). Most of this light rainfall is probably lost to evapotranspiration. At least another 20% of total rainfall on Guam arrives at very high intensities (>5.0 cm/day), which tend to promote fast flow at the expense of percolation. Rapid recovery of the water table from rapid recharge suggests that the lens either takes such recharge into storage very rapidly, discharges it rapidly without taking it into storage, or some combination of both. Significant vadose buffering of recharge to the lens is indicated by the fact that simulations assuming that the recharge from precipitation received in any given month is transmitted to the lens during the same month consistently over-predict observed peak mean monthly water levels and under-predict the minima. (C) 2002 Elsevier Science B.V. All rights reserved

Solid waste disposal in the Environmental Protected Area of the Lagoa Santa Karst, Minas Gerais State, Brazil, 2008, Travassos L. E. P, Sampaio J. L. D, GuimarÃ, Es R. L. , Kohler H. C.

The State of Minas Gerais, Brazil, has approximately 580,000 sq km. From this total, it?s believed that at about 29,000 sq km are composed by carbonatic rocks.With a total of 853 municipalities and some noticeable environmental problems, the biggest problem is the proper final waste disposal. This work is intended to demonstrate the potential pollution of karst aquifers due to leachate?s percolation from improper waste disposal sites. In Brazil, it was established three categories to designate them. From the most environmentally incorrect sites for waste disposal to the better suitable for these activities it is possible to identify the waste dumps (lixões), controlled landfills (aterros controlados) and sanitary landfills (aterros sanitários). In each Brazilian State, around 80% of their municipalities have less than 20,000 inhabitants and no sufficient financial resources required to construct a sanitary landfill. It is also observed a certain degree of lack of political will from some municipal administrations to execute these projects. Unfortunately, some of these areas are located in karst terrains and therefore it is important to observe that an effective environmental control is not always made. The region of Lagoa Santa, State of Minas Gerais, is developed on metasediments of the Bambui Group, Sete Lagoas Formation (Upper Proterozoic). This rock Formation favors the development of expressive superficial and underground karst features. Moreover, the region presents great paleontological, archaeological, historical and speleological potential, which must also be protected from quarrying, pressures from population growth and uncontrolled touristic activities. In 1990 this scenario favored the creation of an Environmental Protected Area (Área de Proteção Ambiental - APA) to preserve local fauna and flora as well the physical environment. However, for many years the APA?s municipalities and its surroundings had installed waste dumps (lixões) since the end of the 70´s.With the State Guideline nº 52 (Deliberação Normativa nº 52) from December 2001, the State Government decreed the adequacy of such irregular dumps. The Guidelines clearly states that the waste must be deposit in a site with soil and/or low permeability rocks, with less than 30% steep angles, a minimum distance of 300m from water sources and 500m distant from core population. Furthermore, the standardization requires the municipalities to implement rainwater drainage systems around the site to reduce water percolation. The Document also obligates the municipality to compact and cover the waste cells at least three times a week, isolating the area to avoid human and animal access. In 2005, the state had registered 25 sanitary landfills, 199 controlled landfills and 549 waste dumps. In February 2007 the State Environmental Agency (FEAM) pointed out the same number of landfills, 207 controlled landfills and still a large amount of waste dumps: 519. Sadly, these inappropriate dumps (lixões) that were controlled in or near karst areas still poses as a threat to the environment since all the contamination comes from at least 25 years ago.


A Three-dimensional Statistical Model of Karst Flow Conduits, 2016, Boudinet, P

It already exists several three-dimensional models dealing with groundwater circulation in karst systems. However, few of them are able either to give a large scale prediction of the repartition of the flow conduits or to make a comparison with real field data. Therefore, our objective is to develop a three-dimensional model about the early formation of karst flow conduits and to compare it with actual field data. This geometric and statistical model is based on percolation and random walks. It is computational and can be run on a personal computer. We examine the influence of fissures (joints and bedding planes) of variable permeability and orientations on the development or early flow conduits. The results presented here correspond to computations up to 2015. Because of long runtimes, we focused on some particular stereotypical situations, corresponding to some particular values of the parameters. Regarding the conduit patterns, the opening and directions of fissures have the same qualitative influence in the model than in actual systems. Two other predictions in good accordance with real karst are that flow conduits can either develop close to the water table or deeper, depending on the distribution of permeable fissures; and that, when viewed in the horizontal plane, conduits don't always develop close to the straight line between inlet and outlet. From a quantitative point of view, in the case of weak dips, our model predicts a realistic relationship between the stratal dip, the length of the system and the averaged depth of the conduits. Eventually, we show that the repartition of conduits depends not only on obvious geometrical parameters such as directions and sizes, but also also on other quantities difficult to measure such as the probability of finding open fissures. The lack of such data doesn't enable, at the present time, a whole comparison between model and reality.


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