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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 soil (Keyword) returned 533 results for the whole karstbase:
Showing 46 to 60 of 533
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The effect of groundwater on the engineering behaviour of soils and rocks is of fundamental importance, indeed to paraphrase Tergazhi -- without water there would be no soil mechanics. This paper reviews these effects in terms of the variation in the properties and behaviour of soils and rocks brought about by changes in moisture content, and associated changes, notably in effective stress, and by the dissolution of parts of the rock or soil mass
The geology and karstic nature of the Kuala Lumpur (Malaysia) limestone are described in relation to pile foundation problems of heavily loaded structures. The presence of cavities, pinnacles, cantilever slabs, floating slabs and pockets of soft silty clay and loose sand in the underlying limestone bedrock presents formidable challenges to foundation engineers. Other problems include insufficient seating and damage to pile tips due to irregular and sloping bedrock surfaces. There is also the added difficulty of detecting the location and extent of cavities. Empirical design methods and local construction techniques have been successfully used such as: (i) bridging limestone cavities and slabs by filling with concrete, (ii) utilizing numerous small diameter high yield stress piles to distribute the loads and to withstand high driving stresses, (iii) filling cavities with concrete, and (iv) using micropiles to redistribute the loads. Two case histories are presented, consisting of an access ramp and a tall building. In each of these case histories, the soil investigation methods, the pile bearing capacity calculations, the selection of pile types, the pile load tests, the pile driving criteria, and construction problems are outlined and discussed. The pile foundation used consisted of H-section, high yield stress, 355 x 368 mm, driven steel piles with capacities of 750 kN to 1280 kN for the access ramp structures and the same H-section steel piles with pile capacities of 965 kN to 1070 kN for the tall building
Ideal climatic and ecological conditions in many caves in the Chillagoe area suggest the existence of Histoplasma capsulatum. A study in progress proposes to identify those caves that may be reservoirs for the organism, thus presenting a potential health risk for cave visitors. Soil samples collected from caves containing bat and bird (swiftlet) populations are being processed by the Division of Mycotic Diseases, at the Center for Disease Control, Atlanta, Georgia. Preliminary results from 15 caves have been negative, thus a more precise technique will be utilised in further collections. Intradermal histoplasmin skin testing of cavers intends to identify the possibility of cave exploration as one source of Histoplasma capsulatum exposure.
The impact of the hydrodynamic properties of the karst substratum over the soil characteristic in mediterranean areas - The weathering and pedogenetic evolution on limestones in mediterranean areas leads to the formation of a more or less decarbonated red soil. This evolution passes through successive stages of decarbonatation, rubification and decalcification and can be associated with a colour change, which includes lithochromic, brown and red phases. It is obviously influenced by the hydrodynamic properties of the soils and by the underground drainage characteristics of the substratum: hence soils developed over almost impermeable marly limestones remain at the lithochromic and/or brown levels, and decarbonatation remains weak; on hard and fractured limestones, pedogenesis is much more active and, even if the weathering volume on this rather pure rocks is small, the soil profile becomes almost completely devoid of free lime; under certain conditions a slight decalcification of the soil sorption complex may even be observed.
Gamma-ray scintillation spectrometry has been used to measure the 137Cs and 134Cs levels and depth distributions in soil of a tea plantation in the Eastern Black Sea region in Turkey. Soil samples were collected in November 1987. The depth distribution was found to be exponential with [alpha] = 0.16 cm-1 and the exposure rate arising therefrom is calculated as 17.46 [mu]R/h over the ground surface
The discharge and chemical properties of 217 autogenic groundwaters were monitored over a 1-yr period in the tower karsts of central Selangor and the Kinta Valley, and in the Setul Boundary Range. Because of differences in soil PCO2, calcium concentrations are significantly higher in the Boundary Range (mean, 82.5 mg l-1) than in the tower karst terrain (44.6 mg l-1). Local differences in both source area PCO2 and amounts of secondary deposition underground cause marked intersite variability, particularly in the tower karst. Dilution occurs during flood peaks in certain conduit and cave stream waters. Generally, however, calcium correlates positively with discharge, since the amount of secondary deposition per unit volume of water decreases at higher flows. Magnesium concentrations and Mg:Ca Mg ratios of groundwaters are strongly influenced by bedrock composition, though bedrock heterogeneity and the kinetics and equilibria of carbonate dissolution reactions preclude extremely low or high Mg:Ca Mg values. Net chemical denudation rates range from 56.6 to 70.9 m3km2yr-1.The results are considered in relation to cation fluxes in surface runoff, soil throughflow and nutrient cycling. Preliminary calcium and magnesium budgets show that (1) dissolutional activity is largely confined to the near-surface zone; and (2) the annual uptake of calcium and magnesium by tropical limestone forests is similar in magnitude to the net solute output in groundwaters
C-14 activity of dissolved inorganic carbon (DIC) in water and in recent tufa samples in several karst areas of Yugoslavia and Czechoslovakia was measured. Groundwater from 11 karst springs were measured for their isotopic content (C-14, H-3, C-13), chemical composition (HCO3, Ca2, Mg2) and physico-chemical properties (temperature, pH). Seasonal variations of the C-14 activity of DIC in two karst springs in Plitvice Lakes area, Yugoslavia, were measured systematically from 1979-1987. C-14 activity of recent tufa samples from several locations downstream were also measured. The activity of DIC in karst spring water in both countries ranged from 63-87 pMC, which is attributed to differences in geologic structure of the recharge area, topsoil thickness and composition. Grouping of C-14 activities of DIC ca (824)% is evident. Tritium activity at all the springs indicated short mean residence time (1-10 yr). Concentration of HCO3, Ca2 and Mg2 in spring water varied with geomorphology. C-14 activity of streamwater and recent tufa increased downstream from karst springs due to the exchange between atmospheric CO2 and DIC
Widespread but patchily distributed drought death of forest trees occurred in early 1988 on a limestone ridge at Mole Creek in Tasmania. A close juxtaposition of damaged and undamaged vegetation probably reflects differences in the speed of soil moisture decline down the length of individual soil-filled solution tubes in which trees are rooted. Possible palaeoecological, geomorphological and sivicultural implications are briefly reviewed.
PRESENTATION OF THE MAIN CAVES OF THE CAUSSE OF LAISSAC-SEVERAC (AVEYRON, FRANCE) - The causse of Laissac-Severac is situated between "Grands Causses" and "Causse of Sauveterre" (Aveyron), in limestones and dolomites of Lias and Middle Jurassic. This speleological area presents two kinds of karst systems: losses and resurgences at the contact of the crystalline massif (Levezou) on the south part (Clos del Pous = 3km), and caves with numerous sumps under the Causse of Severac on the north part (plateau with large depressions (Tantayrou = 3.1km). These caves are post-Miocene because of the dated volcanism; they cut an eogene paleokarst, which is characterised by ferralitic paleosoils (ferruginous sandstone called "Siderolithique") from the alteration of crystalline massif.
KARSTIFICATION AND PALEOGEOGRAPHICAL EVOLUTION OF THE JURA (Fr.) - The karstification started at the beginning of the Tertiary, and the process is still going on today. During the Eocene, modifications brought about under the tropical climate resulted in siderolithic deposits (siliceous sands, ferruginous soils), which can be found in some fossil karsts. In the Oligocene, active tectonics modified the Eocene surface. Erosion during the Miocene levelled the Jura Mountains into a peneplain even though the climate remained tropical. Toward the end of the Miocene, present-day structure and landforms were produced when the main folding, subjected at the same time to powerful erosion, occurred. During the Upper Pleistocene the climate became cooler and wetter. At least two glacial periods have been recognised in the Pleistocene. Present-day karst landforms and most of the caves can be considered as being shaped during the Plio-Quaternary. The karst fillings of the Quaternary provide evidence of the extension of the Würm and Riss glaciers.
Differences in the fracture type of limestone rocks have resulted in the formation of several main plant soil ecosystems in the montane and subalpine zones of the Jura (800-1 700 m). The sites were on stable landscape with slope < 5%. Locations were chosen to reflect the variation in physical properties of the bedrock and lithic contact. The rock fractures (densities and size), the shape and size of the fragments and the hydraulic conductivities were described and analyzed to characterize the 3 main bedrocks in the area studied (table 1): 1), lapiaz, ie, large rock fragments separated from each other by wide fractures (figs 1-2), 'broken' rocks traversed by numerous fine fractures (fig 2-3), paving-stones crossed by infrequent narrow fractures (fig 3). The effects of rock fracturing on vegetation (table II) and soil formation were significant in reference to porosity and permeability relationships (figs 6-7). Under similar precipitation, meteoric waters flow through the soil and porosity is relative to fracture systems (figs 4, 5). The weathering of cobbles in the soil profiles and along the lithic contacts maintains different soil solution Ca levels and is an important variable in soil and ecosystem formation (table III). Regarding the regional orogenic phases and the tectonic origin of the fractures, we postulate that the different types of fracturation originated from the different chemical and mineralogic composition of the rocks. Significant differences exist in both the calcite and dolomite content, in the insoluble residue content (table IV) and in the percentage of organic matter of the carbonate-free residues (table V, fig 8). The results indicate that the differences in rock composition arose early at about the period of sedimentation. The origin of the differentiation might be due to the sedimentation conditions and environment (fig 9). It is concluded that the present-day plant soil ecosystems may be related to the marine sediment environments of the Jurassic period (fig 10)
Results 46 to 60 of 533
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