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Community news

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 natural load is sediment carried by a stable stream [16].?

Checkout all 2699 terms in the KarstBase Glossary of Karst and Cave Terms


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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 joints (Keyword) returned 97 results for the whole karstbase:
Showing 91 to 97 of 97
Karstification of Dolomitic Hills at south of Coimbra (western-central Portugal) - Depositional facies and stratigraphic controls of the (palaeo)karst affecting the Coimbra Group (Lower Jurassic), 2014,
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Dimuccio, Luca Antonio

An evolutionary model is proposed to explain the spatio-temporal distribution of karstification affecting the Lower Jurassic shallow-marine carbonate succession (Coimbra Group) of the Lusitanian Basin, cropping out in the Coimbra-Penela region (western-central Portugal), in a specific morphostructural setting (Dolomitic Hills). Indeed, in the Coimbra Group, despite the local lateral and vertical distributions of dolomitic character and the presence of few thick sandy-argillaceous/shale and marly interbeds, some (meso)karstification was identified, including several microkarstification features. All types of karst forms are commonly filled by autochthonous and/or allochthonous post-Jurassic siliciclastics, implying a palaeokarstic nature.

The main aim of this work is to infer the interplay between depositional facies, diagenesis, syn- and postdepositional discontinuities and the spatio-temporal distribution of palaeokarst. Here, the palaeokarst concept is not limited to the definition of a landform and/or possibly to an associated deposit (both resulting from one or more processes/mechanisms), but is considered as part of the local and regional geological record.

Detailed field information from 21 stratigraphic sections (among several dozens of other observations) and from structural-geology and geomorphological surveys, was mapped and recorded on graphic logs showing the lithological succession, including sedimentological, palaeontological and structural data. Facies determination was based on field observations of textures and sedimentary structures and laboratory petrographic analysis of thin-sections. The karst and palaeokarst forms (both superficial and underground) were classified and judged on the basis of present-day geographic location, morphology, associated discontinuities, stratigraphic position and degree of burial by post-Jurassic siliciclastics that allowed to distinguish a exposed karst (denuded or completely exhumed) than a palaeokarst (covered or partially buried).

A formal lithostratigrafic framework was proposed for the local ca. 110-m-thick combined successions of Coimbra Group, ranging in age from the early Sinemurian to the early Pliensbachian and recorded in two distinct subunits: the Coimbra formation, essentially dolomitic; and the overlying S. Miguel formation, essentially dolomitic-limestone and marly-limestone.

The 15 identified facies were subsequently grouped into 4 genetically related facies associations indicative of sedimentation within supra/intertidal, shallow partially restricted subtidal-lagoonal, shoal and more open-marine (sub)environments - in the context of depositional systems of a tidal flat and a very shallow, inner part of a low-gradient, carbonate ramp. In some cases, thick bedded breccia bodies (tempestites/sismites) are associated to synsedimentary deformation structures (slumps, sliding to the W to NW), showing the important activity of N–S and NNE–SSW faults, during the Sinemurian. All these deposits are arranged into metre-scale, mostly shallowing-upward cycles, in some cases truncated by subaerial exposure events. However, no evidence of mature pedogenetic alteration, or the development of distinct soil horizons, was observed. These facts reflect very short-term subaerial exposure intervals (intermittent/ephemeral), in a semiarid palaeoclimatic setting but with an increase in the humidity conditions during the eogenetic stage of the Coimbra Group, which may have promoted the development of micropalaeokarstic dissolution (eogenetic karst).

Two types of dolomitization are recognized: one (a) syndepositional (or early diagenetic), massive-stratiform, of “penesaline type”, possibly resulting from refluxing brines (shallow-subtidal), with a primary dolomite related to the evaporation of seawater, under semiarid conditions (supra/intertidal) and the concurrent action of microbial activity; another (b) later, localized, common during diagenesis (sometimes with dedolomitization), particularly where fluids followed discontinuities such as joints, faults, bedding planes and, in some cases, pre-existing palaeokarstic features.

The very specific stratigraphic position of the (palaeo)karst features is understood as a consequence of high facies/microfacies heterogeneities and contrasts in porosity (both depositional and its early diagenetic modifications), providing efficient hydraulic circulation through the development of meso- and macropermeability contributed by syn- and postdepositional discontinuities such as bedding planes, joints and faults. These hydraulic connections significantly influenced and controlled the earliest karst-forming processes (inception), as well as the degree of subsequent karstification during the mesogenetic/telogenetic stages of the Coimbra Group. Multiple and complex karstification (polyphase and polygenic) were recognized, including 8 main phases, to local scale, integrated in 4 periods, to regional scale: Jurassic, Lower Cretaceous, pre-Pliocene and Pliocene-Quaternary. Each phase of karstification comprise a specific type of (palaeo)karst (eogenetic, subjacent, denuded, mantled-buried and exhumed).

Finally, geological, geomorphological and hydrogeological characteristics allowed to describe the local aquifer. The elaborated map of intrinsic vulnerability shows a karst/fissured and partially buried aquifer (palaeokarst) with high to very high susceptibility to the contamination.


The formation of the pinnacle karst in Pleistocene aeolian calcarenites (Tamala Limestone) in southwestern Australia, 2015,
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A spectacular pinnacle karst in the southwestern coastal part of Western Australia consists of dense fields of thousands of pinnacles up to 5 m high, 2 m wide and 0.5–5 m apart, particularly well exposed in Nambung National Park. The pinnacles have formed in the Pleistocene Tamala Limestone, which comprises cyclic sequences of aeolian calcarenite, calcrete/microbialite and palaeosol. The morphology of the pinnacles varies according to the lithology in which they have formed: typically conical in aeolianite and cylindrical in microbialite. Detailed mapping and mineralogical, chemical and isotopic analyses were used to constrain the origin of the pinnacles, which are residual features resulting mainly from solutional widening and coalescence of solution pipeswithin the Tamala Limestone. The pinnacles are generally joined at the base, and the stratigraphy exposed in their sides is often continuous between adjacent pinnacles. Some pinnacles are cemented infills of solution pipes, but solution still contributed to their origin by removing the surrounding material. Although a number of pinnacles contain calcified plant roots, trees were not a major factor in their formation. Pinnacle karst in older, better-cemented limestones elsewhere in theworld is similar inmorphology and origin to the Nambung pinnacles, but is mainly influenced by joints and fractures (not evident at Nambung). The extensive dissolution associatedwith pinnacle formation at Nambung resulted in a large amount of insoluble quartz residue, which was redeposited to often bury the pinnacles. This period of karstification occurred at aroundMIS 5e, and therewas an earlier, less intense period of pinnacle development duringMIS 10–11. Both periods of pinnacle formation probably occurred during the higher rainfall periods that characterise the transition from interglacial to glacial episodes in southern Australia; the extensive karstification around MIS 5e indicates that the climate was particularly humid in southwestern Australia at this time.


Caves in the Buda Mountains, 2015,
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LeélŐssy, Szabolcs

On the territory of Budapest, there are about 170 caves: mainly in the Rózsadomb (Rose Hill) area. The total known length of these caves (in the city) is more than 52 km. The caves of Budapest are hypogene (thermal karstic) caves, dissolved by mixing corrosion of ascending waters along tectonic joints. Therefore, the cave passages are totally independent of surface morphology, and there are no fluviatile sediments in the caves. The origin of the caves can be reconstructed from the careful reconstruction of underground circulation routes. The caves are characterized by varied morphological features: spherical cavities along corridors of various size, the walls and floors, sometimes even the ceilings, of which are well decorated with mineral precipitations (calcite, aragonite and gypsum, a total of almost 20 minerals), the most common being botryoids, but dripstones are also common. The cave passages are mainly formed in the Eocene Szépvölgy Limestone Formation, but the upper part is often in Eocene-Oligocene Buda Marl. The deepest horizon is sometimes in the Triassic limestone (Mátyáshegy Formation). Based on U-series dating of their minerals, the Buda caves are very young (between 0.5 and 1 Ma).


TECTONIC CONTROL OF CAVE DEVELOPMENT: A CASE STUDY OF THE BYSTRA VALLEY IN THE TATRA MTS., POLAND, 2015,
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Tectonic research and morphologi calobservations were carried out in six caves (Kalacka, Goryczkowa, Kasprowa Ni¿na, Kasprowa OErednia, Kasprowa Wy¿nia and Magurska) in the Bystra Val ley, in the Tatra Moun -tains. There are three cave lev els, with the youn gest ac tive and the other two in ac tive, re flect ing de vel op ment partly un der epiphreatic and partly un der phreatic con di tions. These stud ies dem on strate strong con trol of the cave pat tern by tec tonic fea tures, in clud ing faults and re lated frac tures that orig i nated or were re ju ve nated dur ing up lift,last ing from the Late Mio cene. In a few lo cal cases, the cave pas sages are guided by the com bined in flu ence of bed ding, joints and frac tures in the hinge zone of a chev ron anticline. That these cave pas sages are guided by tec tonic struc tures, ir re spec tive of lithological dif fer ences, in di cates that these proto-con duits were formed by “tec tonic in cep tion”. Dif fer ences in the cave pat tern be tween the phreatic and epiphreatic zones at a given cave level may be a re sult of mas sif re lax ation. Be low the bot tom of the val ley, the ef fect of stress on the rock mass is re lated to the re gional stress field and only in di vid ual faults ex tend be low the bot tom of the val ley. Thus in the phreatic zone, the flow is fo cused and a sin gle con duit be comes en larged. The lo cal ex ten sion is more in tense in the epiphreatic zone above the val ley floor and more frac tures have been suf fi ciently ex tended to al low wa ter to flow. The wa ter mi grates along a net work of fis sures and a maze could be form ing. Neotectonic dis place ments (of up to 15 cm), which are more re cent than the pas sages, were also iden ti fied in the caves. Neotectonic ac tiv ity is no lon ger be lieved to have as great an im pact on cave mor phol ogy as pre vi ously was thought. Those faults with dis place ments of sev eral metres, de scribed as youn ger than the cave by other au thors, should be re clas si fied as older faults, the sur faces of which have been ex posed by speleogenesis. The pos si ble pres ence of neotectonic faults with greater dis place ments is not ex cluded, but they would have had a much greater mor pho log i cal im pact than the ob served fea tures sug gest.


Tectonic control of cave development: a case study of the Bystra Valley in the Tatra Mts., 2015,
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Szczygieł Jacek, Gaidzik Krzysztof, Kicińska Ditta

Tectonic research and morphological observations were carried out in six caves (Kalacka, Goryczkowa, Kasprowa Niżna, Kasprowa Średnia, Kasprowa Wyżnia and Magurska) in the Bystra Valley, in the Tatra Mountains. There are three cave levels, with the youngest active and the other two inactive, reflecting development partly under epiphreatic and partly under phreatic conditions. These studies demonstrate strong control of the cave pattern by tectonic features, including faults and related fractures that originated or were rejuvenated during uplift, lasting from the Late Miocene. In a few local cases, the cave passages are guided by the combined influence of bedding, joints and fractures in the hinge zone of a chevron anticline. That these cave passages are guided by tectonic structures, irrespective of lithological differences, indicates that these proto-conduits were formed by "tectonic inception”. Differences in the cave pattern between the phreatic and epiphreatic zones at a given cave level may be a result of massif relaxation. Below the bottom of the valley, the effect of stress on the rock mass is related to the regional stress field and only individual faults extend below the bottom of the valley. Thus in the phreatic zone, the flow is focused and a single conduit becomes enlarged. The local extension is more intense in the epiphreatic zone above the valley floor and more fractures have been sufficiently extended to allow water to flow. The water migrates along a network of fissures and a maze could be forming. Neotectonic displacements (of up to 15 cm), which are more recent than the passages, were also identified in the caves. Neotectonic activity is no longer believed to have as great an impact on cave morphology as previously was thought. Those faults with displacements of several metres, described as younger than the cave by other authors, should be reclassified as older faults, the surfaces of which have been exposed by speleogenesis. The possible presence of neotectonic faults with greater displacements is not excluded, but they would have had a much greater morphological impact than the observed features suggest.


Superposed folding and associated fracturing influence hypogene karst development in Neoproterozoic carbonates, São Francisco Craton, Brazil, 2015,
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Porosity and permeability along fractured zones in carbonates could be significantly enhanced by ascending fluid flow, resulting in hypogene karst development. This work presents a detailed structural analysis of the longest cave system in South America to investigate the relationship between patterns of karst conduits and regional deformation. Our study area encompasses the Toca da Boa Vista (TBV) and Toca da Barriguda (TBR) caves, which are ca. 107 km and 34 km long, respectively. This cave system occurs in Neoproterozoic carbonates of the Salitre Formation in the northern part of the São Francisco Craton, Brazil. The fold belts that are around and at the craton edges were deformed in a compressive setting during the Brasiliano orogeny between 750 and 540 Ma. Based on the integrated analysis of the folds and brittle deformation in the caves and in outcrops of the surrounding region, we show the following: (1) The caves occur in a tectonic transpressive corridor along a regional thrust belt; (2) major cave passages, at the middle storey of the system, considering both length and frequency, developed laterally along mainly (a) NE–SW to E–W and (b) N to S oriented anticline hinges; (3) conduitswere formed by dissolutional enlargement of subvertical joints,which present a high concentration along anticline hinges due to folding of competent grainstone layers; (4) the first folding event F1was previously documented in the region and corresponds with NW–SE- to N–S-trending compression, whereas the second event F2, documented for the first time in the present study, is related to E–Wcompression; and (5) both folding  еvents occurred during the Brasiliano orogeny. We conclude that fluid flow and related dissolution pathways have a close relationship with regional deformation events, thus enhancing our ability to predict karst patterns in layered carbonates.


A Three-dimensional Statistical Model of Karst Flow Conduits, 2016,
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Boudinet, P

It already exists several three-dimensional models dealing with groundwater circulation in karst systems. However, few of them are able either to give a large scale prediction of the repartition of the flow conduits or to make a comparison with real field data. Therefore, our objective is to develop a three-dimensional model about the early formation of karst flow conduits and to compare it with actual field data. This geometric and statistical model is based on percolation and random walks. It is computational and can be run on a personal computer. We examine the influence of fissures (joints and bedding planes) of variable permeability and orientations on the development or early flow conduits. The results presented here correspond to computations up to 2015. Because of long runtimes, we focused on some particular stereotypical situations, corresponding to some particular values of the parameters. Regarding the conduit patterns, the opening and directions of fissures have the same qualitative influence in the model than in actual systems. Two other predictions in good accordance with real karst are that flow conduits can either develop close to the water table or deeper, depending on the distribution of permeable fissures; and that, when viewed in the horizontal plane, conduits don't always develop close to the straight line between inlet and outlet. From a quantitative point of view, in the case of weak dips, our model predicts a realistic relationship between the stratal dip, the length of the system and the averaged depth of the conduits. Eventually, we show that the repartition of conduits depends not only on obvious geometrical parameters such as directions and sizes, but also also on other quantities difficult to measure such as the probability of finding open fissures. The lack of such data doesn't enable, at the present time, a whole comparison between model and reality.


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