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KarstBase a bibliography database in karst and cave science.
Featured articles from Cave & Karst Science Journals
Characterization of minothems at Libiola (NW Italy): morphological, mineralogical, and geochemical study, Carbone Cristina; Dinelli Enrico; De Waele Jo
Chemistry and Karst, White, William B.
The karst paradigm: changes, trends and perspectives, Klimchouk, Alexander
Long-term erosion rate measurements in gypsum caves of Sorbas (SE Spain) by the Micro-Erosion Meter method, Sanna, Laura; De Waele, Jo; Calaforra, José Maria; Forti, Paolo
The use of damaged speleothems and in situ fault displacement monitoring to characterise active tectonic structures: an example from Zapadni Cave, Czech Republic , Briestensky, Milos; Stemberk, Josef; Rowberry, Matt D.;
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 assessment (Keyword) returned 199 results for the whole karstbase:
Showing 1 to 15 of 199
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SummaryKarst aquifers are the main groundwater resource in Lebanon as well as in most Mediterranean countries. Most of them are not exploited in a sustainable way, partly because their characteristics remain unknown. Karst aquifers are so complex that the assessment of their resource and their exploitable storage requires an analysis of their whole functioning, particularly by analysing the spring hydrograph. Among all various methods, the method proposed by Mangin aims to characterize at the same time the recharge conditions and the storage and recession of the saturated zone by analyzing the spring hydrograph. This method defines two parameters, the infiltration delay i, and the regulating power k which are the roots of a classification of karst systems. This classification makes the distinction between karst and porous aquifers considering the value of the regulating power. k is assumed to be lower than 0.5 in karst, and between 0.5 and 1 for all other aquifers, 1 being the upper limit.The study of karst aquifers in Lebanon shows values of k > 0.5, and even 1; former data from the literature show that other karst springs in Middle East have comparable characteristics. In fact, what is not considered by Mangin and others, k is equivalent to a mean residence time in years of water in the saturated zone. So long residence times are normally observed in poorly karstified aquifers, or containing abandoned, not functioning karstification. The geological framework in which the studied springs are located in fact shows that these aquifers have been subject to a long, complex evolution, as a consequence of the base level rising. This rising produced the flooding of the successive karst drainage network, which does not really function anymore and provides a large storage capacity to the aquifer. The very interesting properties of these aquifers make them prime targets for fulfilling the increasing needs of water
This paper gives a first description of the engravings discovered on the walls of Koonalda Cave(N4), Nullarbor Plain, South Australia. It gives a typologic assessment with reference to known parietal art in the caves of Europe, and to cave engravings discovered in the Katherine area of the Northern Territory, Australia. It establishes the possibility of great antiquity and deals briefly with interpretation. This announcement lays no claim to conclusiveness in the argumentation offered as the facts relating to Australian Palaeolithic Man and his environment are as yet insufficiently known.
The geomorphological characteristics of the Chillagoe karst belt are analysed in terms of an evolution controlled by seasonally arid climatic conditions and lithological variation in the metamorphosed host rock.
Protection and management of natural heritage features such as karst landforms requires considered evaluation of the relative significance of individual features. The grounds for significance depend on the perspective taken. Aesthetic, educational, scientific and recreational values are all relevant and must each be given explicit recognition. Karst landforms are often considered primarily from a scientific perspective. The criteria used for evaluation of such natural heritage features for conservation and management purposes need to reflect this full range of values. This means that karst sites may have significance from one or more of these perspectives, as examples of natural features or landscapes, as examples of cultural features or landscapes or as the site of recreation opportunities. Some such sites will be identified as significant because they are representative of their class (irrespective of the relative importance of classes); others will be judged as significant because they are outstanding places of general interest.
Extensive new sonograph coverage in the Eastern Mediterranean allows a re-assessment of the complex relief outside the Hellenic Arc. The trenches to the SE and SW of Crete are similar in their plan view appearance, each having predominantly sinuous or curved structures that are interpreted as the surface expression of major thrusts. Thrusting, possibly imbricate, is also suggested on the central, shallowest part of the Hellenic Outer Ridge where interlocking convex-outward, curved structures occur, along with other faults and folds. These are thought to relate to decollement-type displacement within or beneath evaporite sediments. The structural style deduced from the morphology is consistent with a continuing outward radial push of the Hellenic Arc to the SW, S and SE, rather than with a migration to the SW and strike-slip on the SE side of the arc as proposed by other workers
Results of the author's investigations show the useful application of cave-map-data for tectonic assessment. Considering speleological features, cave genesis, and structural differences, it is possible to select of the cave map's pattern various jointing and stress systems. By 7 selected cave maps, representing areas of different tectonic history (W-Germany, Austria and Switzerland) it will be demonstrated that three types of kinematic joint-systems can be identified (fundamental, orthogonal- fold- and shear-system). Therefore, tectonic models are expected to become more valuable. It must be stated that future tectonic investigations in karst-areas should include the additional use of cave maps.
Presented are results of isotope investigations of waters collected in the karstic area of the Western Tatra Mts. Altogether 35 groundwater samples have been analysed (tritium content, [delta]D, [delta]18O). They represent groundwaters collected on the earth surface (springs, streams, exurgences) as well as waters found in caves. Parallel, systematic isotope analyses of monthly precipitation collected at the Ornak station located in the center of the investigated area were also carried out. The results of isotope investigations fully confirm earlier suggestions that the karst system of the Western Tatra Mts consists of separate independent subsystems exhibiting weak (if any) hydraulic interconnections. Tritium data allow a semi-quantitative assessment of the mean residence time of the baseflow component in the investigated system. It is equal to at least 7/8 years. Eventual further measurements of tritium content should allow a more precise determination of this parameter. [delta]D and [delta]18O analyses of the investigated waters provide a basis for assessment of the Is/I ratio i.e. the ratio of infiltration originating from summer precipitation to the total yearly infiltration. It appears that groundwaters collected in caves exhibit on the average significantly higher D and 18O content compared to groundwaters collected on the surface. Possible reasons of this effect are discussed thoroughly in the paper
Quaternary calcrete, silcrete and gypcrete duricrusts in Karinga Creek drainage system, central Australia, contain abundant late-stage diagnetic features. These indicate repeated episodes of dissolution, precipitation and mobilization of duricrust components in the landscape, following the initial development of the duricrust mantle. 'Mature' duricrust profiles incorporate assemblages of diagnostic textural features and fabrics that clearly indicate the extent of karstification during the past 27 000 years. Diagenetic features in the duricrusts permit recognition of the stages involved in vadose modifications of compositional, textural and morphological features and, hence, assessment of the impact of karst dissolution, precipitation and mobilization of duricrust components under prevailing environmental conditions. At landscape level, the continued development of secondary porosity-permeability zones in topographically elevated areas, and maintenance of effective topographic gradients for soil creep are considered essential for redistribution of duricrust components and lateral and vertical extension of karst features within the Quaternary duricrust mantle. Although developing over a comparatively short span of time, late-stage modification of the Quaternary duricrusts has important implications for evolution of Quaternary landscapes and distribution of groundwater discharge-recharge patterns. Accordingly, differential dissolution and reprecipitation within the duricrust profiles have progressively given way to development of karst solution pipes and cavities, with the latter now acting as effective conduits for recharge of local aquifers in the region
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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