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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 clay colloid is 1. a clay particle having a diameter less than 1 micron (0.001 mm.) 2. a colloidal substance consisting of clay-size particles.?

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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 fractured rock (Keyword) returned 28 results for the whole karstbase:
Showing 16 to 28 of 28
Flow and transport in hierarchically fractured rock., 2002, Doughty C. , Karasaki K.

A comprehensive strategy for understanding flow in carbonate aquifers, 2003, Worthington, S. R. H.

Studies of carbonate aquifers usually either concentrate on sampling the channel flow (e.g. sink to spring tracer testing, spring monitoring) or on sampling the non-channel flow (e.g. borehole measurements). A comprehensive approach is advocated here, integrating both sources of information, as well as measuring the porosity and permeability of the unfractured rock. Representative sampling can be achieved by treating carbonates as triple porosity aquifers, with one-, two-, and three-dimensional porosity elements. The division of carbonate aquifers into "karstic" or "non-karstic" types is unwarranted.


Numerical analysis of conduit evolution in karstic aquifers. PhD Thesis, 2003, Annable, W. K.

Fractured and solutionally enhanced carbonate aquifers supply approximately 20 percent of the Worlds potable water supply. Although in rare cases these geologic settings can geochemically evolve into conduits which are of sufficient size to be explored and interpreted by researchers, the majority of the solutionally enlarged networks providing fresh water supplies remain too small to be directly measured. As such, we rely upon indirect hydraulic testing and tracer studies to infer the complexity and size of such aquifers. Because solutionally enhanced (karstic) aquifers have multiple scales of porosity ranging from matrix flow, fracture flow and open channel conduit flow, they are particularly vulnerable to contamination due to the high rates of chemical transport. In this study, a numerical model which solves for the variably-saturated flow, chemically-reactive transport and sediment transport within fractured carbonate aquifers has been developed to investigate the evolution of proto conduits from discrete fractures towards the minimum limits of caves which can be explored. The model results suggest that, although potentiometric surfaces can be of assistance in forecasting the possible locations of proto conduits at depth, many conduits are never detected using conventional observation wells relying upon hydraulic head data. The model also demonstrates the strong dependence in the pattern of vertical jointing on how conduits may evolve: fractures oriented similar to the mean groundwater flow direction show conduits evolving along the vertical fracture orientation; however, vertical fractures that differ significantly from the mean groundwater flow direction have vastly more complex dissolution networks. The transport of fine-grained sediments within the fractures has been shown to reduce the rates of conduit development in all but the highest velocity regions, resulting in simplified conduit networks, but at accelerated dissolution rates. The fully-coupled advective-dispersive and reactive chemistry equations were employed strictly with equilibrium reactions to simulate calcite dissolution. This study further shows that higher order kinetics in the form of the kinetic trigger effect of White (1997) are not required if diffusion between the rock matrix and the fracture surfaces account for multi-component matrix diffusion effects between the evolving conduits and the carbonate rock matrix according to the diffusional characteristics of the fractured rock system at hand.


Runoff generation in karst catchments: multifractal analysis, 2004, Majone B. , Bellin A. , Borsato A. ,
Time series of hydrological and geochemical signals at two karst springs, located in the Dolomiti del Brenta region, near Trento, Italy, are used to infer how karst catchments work internally to generate runoff. The data analyzed include precipitation, spring flow and electric conductivity of the spring water. All the signals show the signature of multifractality but with different intermittency and non-stationarity. In particular, precipitation and spring flow are shown to have nearly the same degree of nonstationarity and intermittency, while electric conductivity, which mimics the travel time distribution of water in the karst system, is less intermittent and smoother than both spring flow and precipitations. We found that spring flow can be obtained from precipitation through fractional convolution with a power law transfer function. An important result of our study is that the probability distribution of travel times is inconsistent with the advection dispersion equation, while it supports the anomalous transport model. This result is in line with what was observed by Painter et al. [Geophys. Res. Lett. 29 (2002) 21.1] for transport in fractured rocks. (C) 2004 Elsevier B.V. All rights reserved

Characterization of ground water flow from spring discharge in a crystalline rock environment, 2004, Gentry Wm, Burbey Tj,
Recent investigations describing the hydrogeology of the Blue Ridge Province of Virginia suggest the occurrence of multiple aquifers and flow paths that may be responsible for the variable flow behavior of springs and seeps appearing throughout the region. Deep, confined aquifers associated with ubiquitous faults and shallow, variably confined saprolite aquifers may contribute water to spring outlets resulting in significantly different quantities of discharge and water quality. Multiple analyses are required to adequately identify the flow paths to springs. In this investigation, hydrograph analyses, surface electrical resistivity surveys, aquifer tests, and nitrate concentrations are used in conjunction with previously reported analyses from borehole logs and age dating of ground water to identify two distinct flow paths. Results indicate that base flow occurs from a deep fault zone aquifer and such discharge can be maintained even during prolonged periods of drought, while increased discharge identified on hydrograph peaks suggests the occurrence of rapid flow through the saprolite aquifer within a radius of about 25 meters of the spring orifice. Springflow hydrograph analysis is suitable for rapid characterization of flow paths leading to spring outlets. Rapid characterization is important for evaluation of potential water quality problems arising from contamination of shallow and deep aquifers and for evaluation of water resource susceptibility to drought. The techniques evaluated here are suitable for use in other locations in fractured crystalline rock environments

Trends, prospects and challenges in quantifying flow and transport through fractured rocks, 2005, Neuman Shlomo P. ,

Aquifers: the ultimate groundwater-dependent ecosystems, 2006, Humphreys W. F. ,
Australian aquifers support diverse metazoan faunas comprising obligate groundwater inhabitants, largely crustaceans but also including insects, worms, gastropods, mites and fish. They typically comprise short-range endemics, often of relictual lineages and sometimes widely vicariant from their closest relatives. They have been confined to subterranean environments from a range of geological eras and may contain information on the deep history of aquifers. Obligate groundwater fauna ( stygobites) occurs in the void spaces in karst, alluvial and fractured rock aquifers. They have convergent morphologies ( reduction or loss of eyes, pigment, enhanced nonoptic senses, vermiform body form) and depend on energy imported from the surface except in special cases of in situ chemoautotrophic energy fixation. In Australia, many stygofaunas in arid areas occur in brackish to saline waters, although they contain taxa from lineages generally restricted to freshwater systems. They may occur alongside species belonging to taxa considered typical of the marine littoral although far removed in space and time from marine influence. The ecological attributes of stygofauna makes them vulnerable to changes in habitat, which, combined with their taxonomic affinities, makes them a significant issue to biodiversity conservation. The interaction of vegetation and groundwater ecosystems is discussed and, in places, there are conservation issues common to both

HYDROTHERMAL ORIGIN OF ZADLAKA JAMA, AN ANCIENT ALPINE CAVE IN THE JULIAN ALPS, SLOVENIA, 2009, Knez M. , Slabe T.

Zadlaka Jama was formed in an aquifer below the water table level as a dense network along bedding planes and fractures. It is an anastomosing network system of horizontal and vertical tubes. A selection of tubes grew into larger passages. In addition to the speci?c fracture controls, did hydrothermal water flooding the cave from below, contribute to the development of its dense network of passages? PALMER (1995) observes that when water rich in sulphur mixes with water rich in oxygen in zones of fractured rock, initial cave networks develops. Water from the spring below Zadlaka Jama (Figure 1) has a high carbonate and potassium content and total hardness (400 mg/l); chlorides are somewhat higher in the content as is the proportion of sulphates (40 mg/l). DUBLYANSKY (1989) found that water less than 20o C – in this cave temperature of water is 20.7o C - does not cause distinct development of hydrothermal karst, although mixing of waters with different characteristics and temperatures frequently can cause the development of network maze cave systems (DUBLYANSKY, 1997). FORTI (1996) describes the formation of a three-dimensional cave system that was the consequence of mixing thermal water at a declining water table level with percolating water from the surface. At Zadlaka Jama such a mode of cave formation can only be attributed to its early stages, while all other forms are those of varying fast water flows and of filling of the cave with fine grained sediment.


Karstification in unconfined limestone aquifers by mixing of phreatic water with surface water from a local input: A model, 2010, Gabrovš, Ek F. , Dreybrodt W.

When water from the surface of a limestone plain seeps down through the fractured rock to the water table of an unconfined aquifer with low hydraulic gradient containing water saturated with respect to calcite, mixing of these waters causes renewed aggressivity. A model is presented, which describes the evolution of karstification by dissolutional widening of the fractures downgradient from the local input of surface water. The model couples flow in the fractures with dissolution rates. Dissolution rates are given by F = k (1 [1] c (x)/ceq)4, where c (x) is the calcium concentration at distance x from the entrance of the fracture, ceq is the equilibrium calcium concentration of the H2O–CaCO3–CO2 solution in the fracture, and k is a rate constant. The model describes two domains of waters saturated with respect to calcite at different partial pressure of CO2. At the borders of these domains the waters mix and create dissolutional widening of the fractures by mixing corrosion. A channel evolves along the border in the downgradient direction by about 100 m in 100 ky. Below this channel a zone of fractures with aperture widths up to 1 cm has originated. The change of the hydraulic conductivity in the mixing zone shifts the border of the domains, allowing the channel to grow in the downgradient direction. Below it the zone of widened fractures is invaded by saturated phreatic water and dissolution stops. This process continues at the downgradient part of the conduit. In summary, we find cave conduits evolving close to the water table, leaving significant cavernous structures below them. A variety of modelling scenarios with different choices of parameters show that this evolution is typical and changes only in details but not in its basic behaviour.


Karstification of aquifers interspersed with non-soluble rocks: From basic principles towards case studies, 2010, Romanov D. , Kaufmann G. , Hiller T.

We have developed a numerical model able to describe the karstification of aquifers in fractured rocks containing soluble (limestone or gypsum) and insoluble layers. When water is flowing along fractures crossing the soluble layers, it is able to dissolve the material there, to increase the aperture width of the conduit, and consequently to increase the local hydraulic conductivity. Depending on the thickness and the distribution of these layers, the dissolution can be active only for limited periods, or during the whole evolution time. Fractures located in insoluble layers do not change at all. We are interested in the integral effect of these local processes and study four simplified scenarios of karstification along a prominent wide conduit crossing a fractured limestone block. We keep the initial and the boundary conditions the same for all scenarios and vary only in the amount and the distribution of the soluble material. We demonstrate that aquifers in 100% limestone, without any insoluble layers, develop along areas with high hydraulic conductivities and high hydraulic gradients, creating channel like pathways. On the other hand aquifers containing soluble layers with limited thickness develop faster and exhibit diffuse patterns determined by the chemical properties of the rock. The second part of the paper is a step towards modeling of real karst systems. We present the evolution of an aquifer located in the vicinity of a large hydraulic structure. All initial and boundary conditions, except the amount and the distribution of the soluble rock, remain the same for all scenarios. As a material example for the bedrock, we chose Gipskeuper from an aquifer along the Birs river in Switzerland. This rock consists of soluble gypsum layers and insoluble clays and marls, with typical layer thickness in the range of millimeters to centimeters. The basic processes discussed in the first part of the paper remain valid. We demonstrate that large insoluble zones can impair the karstification process and even completely block it, while areas with thin soluble layers can provide a preferential pathway and decrease the evolution times considerably. Finally we show that the evolution of the leakage rates and the head distribution within the aquifer can sometimes reveal misleading information about the stage of karstification and the safeness of the dam. Our model can be used not only to study simplified geological settings and basic processes, but also to address some of the complications arising when modeling real aquifers.


Spatially dense drip hydrological monitoring and infiltration behaviour at the Wellington Caves, South East Australia, 2012, Jex Catherine N. , Mariethoz Gregoire, Baker Andy, Graham Peter, Andersen Martin S. , Acworth Ian, Edwards Nerilee, Azcurra Cecilia

Despite the fact that karst regions are recognised as significant groundwater resources, the nature of groundwater flow paths in the unsaturated zone of such fractured rock is at present poorly understood. Many traditional methods for constraining groundwater flow regimes in karst aquifers are focussed on the faster drainage components and are unable to inform on the smaller fracture or matrix-flow components of the system. Caves however, offer a natural inception point to observe both the long term storage and the preferential movement of water through the unsaturated zone of such fractured carbonate rock by monitoring of drip rates of stalactites, soda straws and seepage from fractures/micro fissures that emerge in the cave ceiling. Here we present the largest spatial survey of automated cave drip rate monitoring published to date with the aim of better understanding both karst drip water hydrogeology and the relationship between drip hydrology and surface climate. By the application of cross correlation functions and multi-dimensional scaling, clustered by k-means technique, we demonstrate the nature of the relationships between drip behaviour and initial surface infiltration and similarity amongst the drip rate time series themselves that may be interpreted in terms of flow regimes and cave chamber morphology and lithology.


A laboratory study of tracer tomography, 2013, Brauchler R. , Bhm G. , Leven P. , Dietrich C. , Sauter M.

A tracer tomographic laboratory study was performed with consolidated fractured rock in three-dimensional space. The investigated fractured sandstone sample was characterized by significant matrix permeability. The laboratory transport experiments were conducted using gas-flow and gas-tracer transport techniques that enable the generation of various flow-field patterns via adjustable boundary conditions within a short experimental time period. In total, 72 gas-tracer (helium) tests were performed by systematically changing the injection and monitoring configuration after each test. For the inversion of the tracer breakthrough curves an inversion scheme was applied, based on the transformation of the governing transport equation into a form of the eikonal equation. The reliability of the inversion results was assessed with singular value decomposition of the trajectory density matrix. The applied inversion technique allowed for the three-dimensional reconstruction of the interstitial velocity with a high resolution. The three-dimensional interstitial velocity distribution shows clearly that the transport is dominated by the matrix while the fractures show no apparent influence on the transport responses.


Initial conditions or emergence: What determines dissolution patterns in rough fractures?, 2015,

Dissolution of fractured rocks is often accompanied by the formation of highly localized flow paths. While the fluid flow follows existing fractures in the rock, these fissures do not, in general, open uniformly. Simulations and laboratory experiments have shown that distinct channels or “wormholes”develop within the fracture, from which a single highly localized flow path eventually emerges. The aim of the present work is to investigate how these emerging flow paths are influenced by the initial aperture field. We have simulated the dissolution of a single fracture starting from a spatially correlated aperture distribution. Our results indicate a surprising insensitivity of the evolving dissolution patterns and flow rates to the amplitude and correlation length characterizing the imposed aperture field. We connect the similarity in outcomes to the self-organization of the flow into a small number of wormholes, with the spacing determined of the longest wormholes. We have also investigated the effect of a localized region of increased aperture on the developing dissolution patterns. A competition was observed between the tendency of the high-permeability region to develop the dominant wormhole and the tendency of wormholes to spontaneously nucleate throughout the rest of the fracture. We consider the consequences of these results for the modeling of dissolution in fractured and porous rocks.


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