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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 scaling chip is a thin small rather irregular piece of limestone, commonly crumbly, which has fallen from the ceiling or wall of a cave. a form of cave breakdown [10].?

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 fracture (Keyword) returned 530 results for the whole karstbase:
Showing 16 to 30 of 530
Traits gnraux de l'hydrologie karstique en Basse Cvenne, 1984,
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Fabre, G.
GENERAL FEATURES OF KARSTIC HYDROLOGY IN BASSE CEVENNE (FRANCE) - N to the town of Als (SE Massif Central and Cvennes), a very fractured carbonated belt outcrops. The karst concerns some facies of Trias, Lias-Dogger, Upper Jurassic and Lower Cretaceous. Karstic flows are of two types: toward W, convergent to the important springs of la Tour-Dauthunes, and toward E and divergent. Ggeneral characteristics are presented. Economic aspect is pointed out, just as karstic stream piracy.

Un karst subalpin mditerranen : la rgion Audibergue-Mons (Alpes-Maritimes et Var), 1984,
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Julian M. , Nicod J.
THE KARSTIC AREA AUDIBERGUE-MONS (Prealps of Grasse, Maritime Alps and Var departments) - This area, very important for the karstic superficial features and the caves, is formed by the proximity of plateaus belonging to the structural system of Provence and the higher main subalpine unit of Audibergue. Three fields of sinkholes are especially characteristic: 1/ central Audibergue, controlled by shear fractures and under the influence of nival phenomena; 2/ Fort d'Esclapon, with more various forms and perhaps an older karstic evolution that explains the large inheritance of terra rossa; 3/ Biron that shows deep furrows and sinkholes. The study of the poljes, fluvio-karstic (Caille) or half-opened (Canaux), introduces the problem of the underground karstic hydrology. The dynamics of neotectonics and morphoclimatic systems, specially the old periglacial processes, is considered with reference to the main forms and deposits shown on the map.

The Effect of Anchialine Factors and Fracture Control on Cave Development below Eastern Grand Bahama, 1985,
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Palmer R. J. , Heath L. M.

Formes de relief pseudokarstiques sur Mars, 1985,
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Battistini, R.
PSEUDOKARST LANDFORMS ON MARS - There are many morphologic features on Mars looking like karstic features, principally in aeolian, glacio-eolian and volcanic formations: etch-pitted terrain, sinkholes aligned along fractures, sinuous alignments of large cavities similar to megadolines, etc. Some of these features are probably collapse features, and some others probably thermokarstic features but it is difficult to understand exactly the process of their genesis, in some cases very different from the process of terrestrial morphologic features. We may evoke the possibility of an underground karst on Mars.

Techniques gophysiques de type lectromagntiques appliques l'tude du karst nivernais, 1985,
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Couturaud A. , Benderitter Y.
STUDY OF KARSTIC DRAINS ENVIRONMENT BY GEOPHYSICAL TECHNIQUES (ELECTRIC AND ELECTROMAGNETIC) - Geophysical techniques (electric and electromagnetic) are tested on two underground rivers of the Nivernais karst (Bourgogne, France). The first site is an important dry valley and the second locates at the border of a plateau. No sharp image of the known galleries were obtained on both sites, but the first one shows a higher density of anomalies corresponding to the cave. In the axis of the valley is a weak resistivity anomaly, without any relation with the karstic drainage and which has not superficial origin. This anomaly would be the consequence of a fracturing of bottom valley. Others zones of fractures are evidenced, cross-cutting the conduits. The second one has also weak resistivity zones, independent of the cave, which are interpreted as annex system (hydrological sense). Some reflections on theoretical and methodological aspect of this type of research are proposed.

Le massif du Parmelan, Haute-Savoie, relations fractura-tion-karstification, 1985,
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Masson, M.
THE MASSIF OF PARMELAN, HAUTE-SAVOIE, FRANCE: RELATIONS BETWEEN FRACTURATION AND KARSTIFICATION - The massif of Parmelan (Haute-Savoie), encloses a well-karstified and highly organised perched aquifer. Its simple geological structure and easy-speleological penetration (more than 45km are known) have allowed a statistical study of the fracturation and karstification parameters at different scales. This study shows that the karst has developed on the most frequent fracturation directions (study of the cumulated lengths), whereas its directional distribution in frequency is relatively homogeneous; the most used fractures are the tension faults, linked with the folding of the massif.

Fracture permeability: implications on cave and sinkhole development and their environmental assessments, 1987,
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Veni, G

Morphologie et volution des cavernes et formes superficielles dans les quartzites du Roraima, 1988,
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Galan C. , Lagarde J.
MORPHOGENESIS OF CAVES AND LANDFORMS IN THE PRECAMBRIAN QUARTZITE OF RORAIMA GROUP (VENEZUELA) - This paper describes caves and landforms developed in the Precambrian quartzite of the Roraima Group (1600-1800 My) in the Gran Sabana of Venezuela (cf. Pouyllau and Seurin, in Karstologia, 1985, n 5). High plateaus (Tepuys) are remnants of old erosional surfaces of Secondary-Tertiary age. The weathering of quartzite is produced in fissures by means of the dissolution of the intergranular siliceous cement. Depressions, fields of blocks and small towers, deep fissures characterise the edges of tepuys. Underground passages could be formed by dissolution, arenisation and piping from the fractures which dissect the tepuys. The part of hydrothermalism in speleogenesis is not proved.

Impact des proprits hydrodynamiques du substrat karstique sur la nature du sol en milieu mditerranen, 1989,
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Verheye, W. H.
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.

Le karst du gypse du centre de la dpression de l'Ebre (Espagne), 1990,
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Soriano, M. A.
THE GYPSUM KARST OF THE CENTER OF THE EBRE BASSIN (SPAIN) - The central Ebro basin was filled with evaporitic deposits (gypsum and limestones) during the Miocene. During the Quaternary, several alluvial terrace and pediment levels were developed and they overlay the gypsum deposits. A large number of karstic landforms developed on gypsum have been found. The most important reason is its high solubility. We have found different types of microlandforms. The most important are Rillenkarren, solution pits and micro etching. There are also small tumuli. They are active at present. We have differentiated three macrolandforms: paleocollapses, depressions and alluvial dolines. The paleocollapses are very narrow and deep. They are filled with quaternary materials. They are not active and were generated in the Middle or Upper Pleistocene. The depressions were developed by the gypsum dissolution, together with topographical and geomorphologic factors. They do not seem to be active nowadays. The alluvial dolines are developed on the terrace and pediment deposits, which overlay gypsum materials. There is basin, well and pan-shaped dolines and they are especially frequent in the T2 terrace level. From the study of aerial photographs of different years, the variations in the number and size of dolines and their density have been determined. Natural factors (lithology and fractures), together with human activities (irrigation) are the principal causes in their development.

Sr isotope study of vein and cave calcites from southern Israel, 1990,
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Avigour A, Magaritz M, Issar A, Dodson Mh,
The strontium isotope compositions of secondary calcites from the Negev, southern Israel, were compared to those of the marine carbonate host rocks, which range in age from Triassic to Eocene, in order to understand fluid source and migration through fracture systems in dominantly carbonate strata. The Sr isotopes of these calcite clusters are divided into two groups: (1) calcites with 87Sr/86Sr values greater than those of the host carbonates; and (2) calcites with 87Sr/86Sr values close to the values of the host carbonate. 1. (1) These secondary calcites were found on the main tectonic lines of the Negev (faults and fold axes) and are enriched in 87Sr (87Sr/86Sr = 0.707709-0.709151) relative to the marine carbonate country rocks (87Sr/86Sr = 0.707251-0.70755, with one exception). These calcites are associated or crossed by thin veins filled by Fe- and Mn-oxides.2. (2) Secondary calcites with 87Sr/86Sr values close to those of the marine carbonate country rocks (0.7073-0.7077) are found in karstic caves and veins, and are located in sites which are not on the major faults and fold axes. These calcites are not crossed by Fe- and Mn-oxides.The isotopic results indicate that the solutions from which the secondary minerals of the first group precipitated were not in isotopic equilibrium with the marine host rocks. The possible source of the precipitating solutions can be either surface rain descending through the fault system or ascending groundwaters from the deep Nubian aquifer (Paleozoic to Early Cretaceous in age). In both cases there would be a limited interaction with the host sandstone rock which usually is depleted in Sr. The similarity of the 87Sr/86Sr values to those of the host rocks in the second group suggests that the main source of Sr in these calcite crystals was from the dissolution of the marine carbonate country rocks by rain- and flood waters

Yates and other Guadalupian (Kazanian) oil fields, U. S. Permian Basin, 1990,
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Craig Dh,
More than 150 oil and gas fields in west Texas and southeast New Mexico produce from dolomites of Late Permian (Guadalupian [Kazanian]) age. A majority of these fields are situated on platforms or shelves and produce from gentle anticlines or stratigraphic traps sealed beneath a thick sequence of Late Permian evaporites. Many of the productive anticlinal structures are elongate parallel to the strike of depositional facies, are asymmetrical normal to facies strike, and have flank dips of no more than 6{degrees}. They appear to be related primarily to differential compaction over and around bars of skeletal grainstone and packstone. Where the trapping is stratigraphic, it is due to the presence of tight mudstones and wackestones and to secondary cementation by anhydrite and gypsum. The larger of the fields produce from San Andres-Grayburg shelf and shelf margin dolomites. Cumulative production from these fields amounts to more than 12 billion bbl (1.9 x 109 m3) of oil, which is approximately two-thirds of the oil produced from Palaeozoic rocks in the Permian Basin. Eighteen of the fields have produced in the range from 100 million to 1.7 billion bbl (16-271 x 106 m3). Among these large fields is Yates which, since its discovery in October 1926, has produced almost 1.2 billion bbl (192 x 106 m3) out of an estimated original oil-in-place of 4 billion bbl (638 x 106 m3). Flow potentials of 5000 to 20 000 bbl (800 to 3200 m3) per day were not unusual for early Yates wells. The exceptional storage and flow characteristics of the Yates reservoir can be explained in terms of the combined effects of several geologic factors: (1) a vast system of well interconnected pores, including a network of fractures and small caves; (2) oil storage lithologies dominated by porous and permeable bioclastic dolograinstones and dolopackstones; (3) a thick, upper seal of anhydrite and compact dolomite; (4) virtual freedom from the anhydrite cements that occlude much porosity in other fields which are stratigraphic analogues of Yates; (5) unusual structural prominence, which favourably affected diagenetic development of the reservoir and made the field a focus for large volumes of migrating primary and secondary oil; (6) early reservoir pressures considerably above the minimum required to cause wells to flow to the surface, probably related to pressures in a tributary regional aquifer

Rock Joints, 1990,
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Modeling of regional groundwater flow in fractured rock aquifers, PhD Thesis, 1990,
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Kraemer, S. R.

The regional movement of shallow groundwater in the fractured rock aquifer is examined through a conceptual-deterministic modeling approach. The computer program FRACNET represents the fracture zones as straight laminar flow conductors in connection to regional constant head boundaries within an impermeable rock matrix. Regional scale fracture zones are projected onto the horizontal plane, invoking the Dupuit-Forchheimer assumption for flow. The steady state flow solution for the two dimensional case is achieved by requiring nodal flow balances using a Gauss-Seidel iteration. Computer experiments based on statistically generated fracture networks demonstrate the emergence of preferred flow paths due to connectivity of fractures to sources or sinks of water, even in networks of uniformly distributed fractures of constant length and aperture. The implication is that discrete flow, often associated with the local scale, may maintain itself even at a regional scale. The distribution of uniform areal recharge is computed using the Analytic Element Method, and then coupled to the network flow solver to complete the regional water balance. The areal recharge weakens the development of preferential flow pathways. The possible replacement of a discrete fracture network by an equivalent porous medium is also investigated. A Mohr's circle analysis is presented to characterize the tensor relationship between the discharge vector and the piezometric gradient vector, even at scales below the representative elementary volume (REV). A consistent permeability tensor is sought in order to establish the REV scale and justify replacement of the discrete fracture network by an equivalent porous medium. Finally, hydrological factors influencing the chemical dissolution and initiation of conduits in carbonate (karst) terrain are examined. Based on hydrological considerations, and given the appropriate geochemical and hydrogeological conditions, the preferred flow paths are expected to develop with time into caves.


IMPACT OF PAST SEDIMENT ECOLOGY ON ROCK FRACTURATION AND DISTRIBUTION OF CURRENT ECOSYSTEMS (JURA, FRANCE), 1991,
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Gaiffe M, Bruckert S,
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)

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