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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That safe yield is the amount of water that can be safely withdrawn from an aquifer without causing undue effects such as aquifer depletion.?

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.
Engineering challenges in Karst, Stevanović, Zoran; Milanović, Petar
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Featured articles from other Geoscience Journals
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
See all featured articles from other geoscience journals

Search in KarstBase

Your search for numerical model (Keyword) returned 96 results for the whole karstbase:
Showing 91 to 96 of 96
A BRIEF HISTORY OF THE THEORY OF GRAVITY-DRIVEN REGIONAL GROUNDWATER FLOW, 2014, Tóth, J.

The theory of gravity-driven regional groundwater flow was first proposed in 1962/3 based on the Laplace equation. Hydraulic-head patterns were calculated for a two dimensional trapezoidal and homogeneous flow domain with flow lines drawn by hand. The flow region was intended to represent one flank of a stream basin with a periodically undulating water table. At the dawn of numerical modeling the results generated international interest. Numerical models began to be produced with progressively increasing complexity of basin geometry, types and distributions of permeability and time dependent flow. One of the most important results of the first analyses was the birth of the flow-system concept. In a flow system groundwater moves from relatively highly elevated recharge areas, through medium high mid-line regions to relatively low lying discharge areas where it may resurface. Because flow systems are associated with topographic elements of different scale, they are self-organized in hierarchically nested geometric patterns.
The understanding of the systematized structure of basinal groundwater flow soon resulted in the recognition that flow systems act like subsurface conveyor belts. They mobilize and remove matter and heat from the recharge area, pick up more or/and emplace some of it en route, and deposit them in the discharge region. In short: flowing groundwater is a general geologic agent. The original „Theory of regional groundwater flow” became thus expanded into a bimodal umbrella theory with two component theories: i) „The hydraulics of basin-scale groundwater flow” and ii) „The geologic agency of regional groundwater flow”. More than half a century after its conception the theory is extensively analyzed and continues to be applied to a growing number of groundwater related disciplines


Karst water resources in a changing world: Review of hydrological modeling approaches, 2014, Hartmann A. , Goldscheider N. , Wagener T. , Lange J. , Weiler M.

Karst regions represent 7–12% of the Earth’s continental area, and about one quarter of the global population is completely or partially dependent on drinking water from karst aquifers. Climate simulations project a strong increase in temperature and a decrease of precipitation in many karst regions in the world over the next decades. Despite this potentially bleak future, few studies specifically quantify the impact of climate change on karst water resources. This review provides an introduction to karst, its evolution, and its particular hydrological processes. We explore different conceptual models of karst systems and how they can be translated into numerical models of varying complexity and therefore varying data requirements and depths of process representation. We discuss limitations of current karst models and show that at the present state, we face a challenge in terms of data availability and information content of the available data. We conclude by providing new research directions to develop and evaluate better prediction models to address the most challenging problems of karst water resources management, including opportunities for data collection and for karst model applications at so far unprecedented scales


Hydrogeological and Environmental Investigations in Karst Systems, 2014,

Karst is the result of climatic and geohydrological processes, mainly in carbonate and evaporite rocks, during geological periods of Earth history. Dissolution of these rock formations over time has generated karst aquifers and environments of significant water and mineral resources. In addition, beautiful landscapes have been created which constitute natural parks, geosites, and caves. Due to their origin and nature, karstified areas require investigation with special techniques and methodology. International collaboration and discussions on advances in karst research are necessary to promote Karst Science. The International Symposium on Karst Aquifers is one of the worldwide events held periodically to specifically address karst environments. The symposium constitutes an ongoing international forum for scientific discussion on the progress made in research in karst environments. The first and second symposiums were organized in Nerja (near Malaga, Spain), in 1999 and 2002; the third and fourth symposiums were held in Malaga city in 2006 and 2010. The 5th International Symposium on Karst Aquifers (ISKA5) occurred in Malaga on during October 14–16, 2014. It was organized by the Centre of Hydrogeology University of Málaga (CEHIUMA) and the Spanish Geological Survey (IGME), in cooperation with UNESCO and the International Association of Hydrogeologists (IAH) Karst Commission. More than 100 contributions were received from 30 countries on five continents. Presentations made during the symposium and published in this book are a compendium of 70 of these manuscripts. Papers submitted by April 2014, were peer-reviewed and subsequently accepted by the Scientific Committee. Contributions are grouped into five sections:

• Methods Utilized to Study Karst Aquifers.

• Karst Hydrogeology.

• Mining and Engineering in Karst media.

• Karst Cavities.

• Karst Geomorphology and Landscape.

A large part of the contributions, 30 %, is related to Methods Utilized to Study Karst Aquifers. Several issues are addressed: methods for groundwater recharge assessment, dye tracer and stable isotope applications, analysis of hydrodynamic data and hydrochemistry, among others. Most contributions, 40 %, however, are on Karst Hydrogeology. These are primarily in connection with various topics such as numerical modeling in karst, floods, karst groundwater flow, protection of karst aquifers or pollution, and vulnerability in karst. Five percent of the published papers deal with Mining and Engineering in Karst Media. These papers are about tunnels, hydrogeological risks, and karst risk assessment in mining and civil engineering. Another section concerning Karst Cavities encompasses 15 % of the contributions. These chapters deal with corrosion and speleogenetic processes, speleothems, CO2 sources, the global carbon cycle in endokarst, and the study of past climate. Karst Geomorphology and Landscape constitutes the remaining 10 % of the contributions. These papers are related to karst features, wetlands, hypogene speleogenesis, geodiversity, and karstic geosites. The results of project work performed by karst specialists worldwide are described in the book. Included in it are experiences from pilot sites, methodologies, monitoring, and data analyses in various climatic, geological, and hydrogeological contexts. Material presented may be utilized for activities such as teaching and technical-professional applications particularly as they apply to the increasingly multidisciplinary nature of karst studies. Information provided may also be useful to decisions makers in making critical decisions regarding development in karst regions. Scientists and engineers and many of the lay public interested in karst environments will benefit from the contents


On the applicability of geomechanical models for carbonate rock masses interested by karst processes, 2015,

Rock mass classification and geomechanical models have a particular importance for carbonate rocks, due to their peculiar fabric, variability of the main features, and scarce availability of experimental data. Carbonates are particularly sensitive to syn-depositional and post-depositional diagenesis, including dissolution and karstification processes, cementation, recrystallisation, dolomitisation and replacement by other minerals. At the same time, as most of sedimentary rocks, they are typically stratified, laminated, folded, faulted and fractured. The strength and deformability of carbonate rock masses are, therefore, significantly affected by the discontinuities, as well as by their pattern and orientation with respect to the in situ stresses. Further, discontinuities generally cause a distribution of stresses in the rock mass remarkably different from those determined by the classical elastic or elasto-plastic theories for homogeneous continua. Goal of this work is the description of the difficulties in elaborating geomechanical models to depict the stress–strain behavior of karstified carbonate rock masses. Due to such difficulties, a high degree of uncertainty is also present in the selection of the most proper approach, the discontinuum one or the equivalent continuum, and in the numerical model to be used within a specific engineering application as well. The high uncertainty might cause wrong assessments as concerns the geological hazards, the design costs, and the most proper remediation works. Even though recent developments in the application of numerical modeling methods allow to simulate quite well several types of jointed rock masses, as concerns carbonate rock masses many problems in representing their complex geometry in the simulation models still remain, due to peculiarity of the structural elements, and the presence of karst features. In the common practice, the improper use of the geomechanical models comes from a superficial geological study, or from the lack of reliable geological and structural data that, as a consequence, bring to erroneous evaluations of the influence of the geological-structural features on the in situ stress state and the stress–strain rock mass behavior.


Evaluating temporal changes in hydraulic conductivities near karst-terrain dams: Dokan Dam (Kurdistan-Iraq) , 2015, Dafny Elad, Tawfeeq Kochar Jamal, Ghabraie Kazem

Dam sites provide an outstanding opportunity to explore dynamic changes in the groundwater flow regime because of the high hydraulic gradient rapidly induced in their surroundings. This paper investigates the temporal changes of the hydraulic conductivities of the rocks and engineered structures via a thorough analysis of hydrological data collected at the Dokam Dam, Iraq, and a numerical model that simulates the Darcian component of the seepage. Analysis of the data indicates increased seepage with time and suggests that the hydraulic conductivity of the rocks increased as the conductivity of the grout curtain decreased. Conductivity changes on the order of 10−8 m/s, in a 20-yr period were quantified using the numerical analysis. It is postulated that the changes in hydraulic properties in the vicinity of Dokan Dam are due to suspension of fine materials, interbedded in small fissures in the rocks, and re-settlement of these materials along the curtain. Consequently, the importance of the grout curtain to minimize the downstream seepage, not only as a result of the conductivity contrast with the rocks, but also as a barrier to suspended clay sediments, is demonstrated. The numerical analysis also helped us to estimate the proportion of the disconnected karstic conduit flow to the overall flow.


Calculating flux to predict future cave radon concentrations, 2016, Rowberry Matt, Marti Xavi, Frontera Carlos, Van De Wiel Marco, Briestensky Milos

Cave radon concentration measurements reflect the outcome of a perpetual competition which pitches flux against ventilation and radioactive decay. The mass balance equations used to model changes in radon concentration through time routinely treat flux as a constant. This mathematical simplification is acceptable as a first order approximation despite the fact that it sidesteps an intrinsic geological problem: the majority of radon entering a cavity is exhaled as a result of advection along crustal discontinuities whose motions are inhomogeneous in both time and space. In this paper the dynamic nature of flux is investigated and the results are used to predict cave radon concentration for successive iterations. The first part of our numerical modelling procedure focuses on calculating cave air flow velocity while the second part isolates flux in a mass balance equation to simulate real time dependence among the variables. It is then possible to use this information to deliver an expression for computing cave radon concentration for successive iterations. The dynamic variables in the numerical model are represented by the outer temperature, the inner temperature, and the radon concentration while the static variables are represented by the radioactive decay constant and a range of parameters related to geometry of the cavity. Input data were recorded at Driny Cave in the Little Carpathians Mountains of western Slovakia. Here the cave passages have developed along splays of the NE-SW striking Smolenice Fault and a series of transverse faults striking NW-SE. Independent experimental observations of fault slip are provided by three permanently installed mechanical extensometers. Our numerical modelling has revealed four important flux anomalies between January 2010 and August 2011. Each of these flux anomalies was preceded by conspicuous fault slip anomalies. The mathematical procedure outlined in this paper will help to improve our understanding of radon migration along crustal discontinuities and its subsequent exhalation into the atmosphere. Furthermore, as it is possible to supply the model with continuous data, future research will focus on establishing a series of underground monitoring sites with the aim of generating the first real time global radon flux maps.


Results 91 to 96 of 96
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