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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 cave series is a group of caves of similar morphology in a particular district [10]. see also cave group.?

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 fabric (Keyword) returned 72 results for the whole karstbase:
Showing 16 to 30 of 72
Remote sensing of tectonic fabric controlling groundwater flow in Dinaric karst., 1995, Kresic N.

REMOTE-SENSING OF TECTONIC FABRIC CONTROLLING GROUNDWATER-FLOW IN DINARIC KARST, 1995, Kresic N. ,
Geological and hydrogeological remote sensing techniques can be applied very favorably to Dinaric karst in the Balkans, a well-known reference area for studies of karst phenomena. The elements that make karst terrain of the Dinarides suitable for remote sensing are geomorphologic characteristics, in particular the specific surface drainage and karst forms, the varying vegetation that most often reflects the existence of different geologic formations on the surface, and distinct tectonic features. Some of the world's largest springs, ponors (sinks), and dolines are controlled by fractures visible on both satellite images and aerial photographs. Lineaments represent fault zones, systems of close faults with similar strike, or large individual faults which all are young or show recently renewed activity. Their neotectonic character and major importance for karst groundwater flow are confirmed by numerous field investigations including water tracing, geophysical research, and drilling

Rillenkarren in the British Isles, 1996, Vincent P. ,
This paper presents the first descriptions of rillenkarren in the British Isles. Rillenkarren are widely developed at two 'classic' karst locations, namely: the Burren coast of Co. Clare, Ireland, and the Morecambe Bay area of north west England. Rillenkarren are also found on hard Cretaceous chalks of Northern Ireland and Carboniferous limestones on the Anglesey coast, north Wales. The limestones at all sires are very hard, extremely pure and dolomite poor. A logit regression model is developed, based on published rillenkarren data from the Napier Range, Western Australia. The model suggests that the two rock properties, % calcite in the rock fabric and % calcite in the micrite cement are key variables in explaining the presence of rillenkarren. Within the context of the model, these two explanatory variables define a feasible domain for the development of rillenkarren. British rillenkarren data satisfy the conditions of this model

Comparison of annual luminescent and visible laminae in stalagmites, 1997, Genty D, Baker A, Barnes W,
Polished sections of stalagmites from France and Belgium were examined using UV excitation and natural light in order to examine their annual growth laminae. The most prominent luminescence occurs in the dark compact laminae; this would signify that both types form at the end of Autumn or the beginning of Winter when soil organic matter is flushed into the cave. Under UV excitation, and at a weaker magnification, white porous calcite fabric is found to be much more luminescent than the dark compact one. These results could be due either to optical effects associated with porosity or to the higher luminescence of dark compact laminae

Comparaison entre les lamines luminescentes et les lamines visibles annuelles de stalagmites, 1997, Genty D, Baker A, Barnes W,
ResumeLes sections polies de plusieurs stalagmites provenant de France et de Belgique ont ete observees apres une excitation en lumiere ultraviolette (LTV) et en lumiere naturelle pour etudier les lamines annuelles luminescentes et visibles. La luminescence la plus forte se trouve dans les lamines sombres et compactes, ce qui signifierait que ces deux types de lamines se formeraient a la fin de l'automne et au debut de l'hiver, lorsqu'il y a une brusque augmentation du debit et un apport important de matiere organique. Sous excitation laser UV, la calcite blanche et poreuse est beaucoup plus luminescente que la calcite sombre et compacte. Cette luminescence est soit, liee a la porosite, soit a la presence de lamines sombres et compactes plus luminescentes.AbstractPolished sections of stalagmites from France and Belgium were examined using UV excitation and natural light in order to examine their annual growth laminae. The most prominent luminescence occurs in the dark compact laminae, this would signify that both types form at the end of Autumn or the beginning of Winter when soil organic matter is flushed into the cave. Under UV excitation, and at a weaker magnification, white porous calcite fabric is found to be much more luminescent than the dark compact one. These results could be due either to optical effects associated with porosity or to the higher luminescence of dark compact laminae

Ground-water silicifications in the calcareous facies of the Tertiary piedmont deposits of the Atlas Mountain (Hamada du Guir, Morocco), 1997, Thiry M. , Benbrahim M. ,
The Tertiary piedmont deposits (Hamada Formations), on the southern edge of the Haut-Atlas mountains, form extensive tablelands in the Boudenib area. They consist of two main sedimentary sequences, the Hamada de Boudenib and the Hamada du Guir, of Eocene and Miocene age. Both sequences show elastic facies at their base (conglomerates, calcareous sandstones, silty clays) and end with thick lacustrine limestones and pedogenic calcretes are characterised by rather confined facies, palygorskite-rich, with some gypsum in the second sequence. The recent evolution of the region is marked by the dissection of the tableland that is lined with high cliffs. The water flaw is mainly through wide karst features as there is no major river on the tableland. Silicifications which affect the different facies, form pods of various shape and size, and show an erratic spatial distribution. In the calcareous sandstones, there are irregularly shaped tubules of about 5 cm in diameter, more planar bodies from 5 to 50 cm thick, which frequently display voids lined with translucent silica concretions. The conglomerates display relatively few silicifications, the more characteristic ones consist of a silica cortex on some Limestone pebble and silica plates fitting closely the base of the pebbles. The lacustrine limestones and the calcretes from the upper part of the formation show frequently well developed silicifications. These show very variable shapes; horizontally stretching layers, interconnected or isolated amoeba-like bodies, thin slabs, karst micro-breccia, with frequent concretionnary structures, and quartz crystallisations. Limestone nodules remain often included in these silicifications. The more argillaceous facies display either small tubules or thin plates formed of translucent concretionnary silica. As a rule, the importance of the voids and related structures (concretions, drusy crystals) has to be noticed in all these silicifications, sometimes they are also linked with fractures or karst pipes. Petrography of the silica minerals, their relation with the primary structures. their distribution and their succession, give invaluable information on the silicification processes. Microcrystalline and fibrous quartz are the most common silica minerals, including minor amounts of opal and euhedral quartz. But micrographic arrangements show clearly that primary opal deposits have been more extensive and have recrystallized into chalcedony, microcrystalline quartz, or even ''flame-like'' quartz. Silica deposits in voids make up an important part of the silica pods. The tubules and thin plates of translucent silica of the argillaceous facies are formed of laminar chalcedony deposited around voids. Silica deposits in voids are also particularly obvious in the sandstones. The pores between the quartz grains are then cemented by fibrous quartz and little opal. Some samples show very large cemented voids that cannot be related to the primary porosity of the sandstone. These large voids correspond to the dissolution of the primary calcareous cement, which even led to the collapse of the sandstone fabric. In the limestones, there are silicified micro-karst breccia with a very high primary porosity cemented by quartz crystals, and even in the large microcrystalline quartz zones there are numerous void fillings, the primary porosity often exceeding 50%. There is obviously the alternation of silica deposits and calcite dissolution. Beside the void filling, silicifications comprise also matrix epigenesis, that is replacement of the carbonate by silica with preservation of most of the limestone structures, without development of voids. Nevertheless, the epigenesis of the limestone matrix is restricted to the vicinity of the voids. The silicifications relate to diagenetic processes. The main part of the silica is formed of void deposits and matrix replacement (epigenesis) on the edge of the voids. These void deposits give evidence of the feeding solutions. The regularity of the deposits all around the voids point out to a hydrologic regime characterised by a ground-water our now. Silica originates most probably from alteration of the magnesian clay minerals along the ground-water path. Regarding the low solubility of silica in surficial waters, high flows are needed in order to renew continuously the silica precipitated from solution. This points to a relatively humid climate at time of silicification, and to relief and incised landscapes to bring about these high flows

Phototrophic Microorganisms of the Pamukkale, 1997, Pentecost Allan, Bayari Serdar , Yesertener Cahit
The travertines at Pamukkale contain a diverse assemblage of phototrophs: 17 species of cyanobacteria, 16 diatoms, and 5 Chlorophyceae. Two communities were recognized on the active travertines: (1) surficial mats dominated by filamentous cyanobacteria, particularly Lyngbya (Phormidium) laminosum forming soft weakly mineralized layers to 10 mm thick, and (2) a predominantly endolithic assemblage, also dominated by cyanobacteria developing 2-5 mm below the travertine surface. The distribution of these communities is determined largely by water flow and the degree of desiccation. Two further communities are briefly described from nondepositing areas. Most of the active travertine consists of alternating layers of micrite and sparite 0.25-0.75 mm in thickness, which probably result from short-term fluctuations in water flow rather than diel events (photosynthesis, temperature). The presence of needle-fiber calcite in surface samples suggests that evaporation of water may play some part in travertine formation. The phototrophs appear to influence the travertine fabric only locally, where the surficial growths contain strings of calcite crystals ad-hering to the filaments, forming irregularly laminated layers. The hot-spring water is believed to be contaminated with sewage and agricultural effluent, but there was no evidence to suggest that this is currently affecting the travertine deposits. The water is supersaturated with respect to calcite when it contacts the travertine, and precipitation is primarily the result of carbon dioxide evasion. Water chemistry and discharge measurements indicate a total travertine deposition rate of 35 tonnes per day.

Tubular Lava Stalactites and Other Related Segregations, 1998, Allred, K. , Allred, C.
Tubular lava stalactites are found in many lava tubes. Field observations, sample analysis, and comparative studies indicate that these are segregations extruded during cooling from partially crystallized lava at about 1,070 to 1,000C. Retrograde boiling within the lava creates a vuggy fabric and provides a mechanism to expel the interstitial liquid. In addition to tubular lava stalactites, a variety of other lava formations can also result.

Volumetric changes in weathered profiles: iso-element mass balance method questioned by magnetic fabric., 1998, Mathe Pierreetienne.

Les stalagmites : archives environnementales et climatiques haute rsolution, prsentation des protocoles dtudes et premiers rsultats sur des splothmes du Vercors, 1999, Perrette, Yves
Since the late 80's, the detailed study of speleothem has deve_loped from the crossing of two main approachs; one comes from the ques_tions of speleologists confronted with magnificent cave scenery, the other comes from citizen questions about climatic and environmental changes. The aim of this paper is to show the diversity and the relevance of the data collected by such studies on stalagmitic samples from the Vercors -France. The knowledge of the chemical processes of the H20 - CaCO3 - C02 system in the perspective of the karst infiltration leads to ques_tions about the role of the "supstrat". This word has been used to describe the "roofrock" rather than the bedrock. So, to better unders_tand the different modes of drainage in karst, a global hydrologic study of the Choranche cave vadose zone has been realised, e.g. seepage water rates have been monitoring. These recent studies allow us to model the structural and functional hydrologic network of such a well developed karst system. Actually we demonstrated the hierar_chisation of the drainage and the relation between a transmissive system and a capacitive one. They have been used to propose a graphical typology leading to a better appreciation of the various environmental interests of speleothems. Understanding the processes of speleothem environmental and climatic archiving, needs to know the processes of calcite crystal growth. They are briefly presented through some usual fabrics like columnar, palissadic or dendritic ones and through the optical relation between macroscopic colours and crys_talline porosity. It is the evolution of these crystalline features, which creates the laminae. To explain what are laminae, the diffe_rent type of emission by a solid after a laser irradiation are shown. It justifies the choice of two kinds of laminae measurement i.e. reflectance and fluorescence. Then, results of spectroscopic studies which show a covariation between Mn2+ concentration, the maximum intensity wave length of fluorescence spectra and the reflec_tance trend, allow us to consider reflectance measurement as a water excess proxy. This experimental approach is confirmed by the infra annual laminae. The hydrological interest of "visible" laminae (i.e. reflectance one) is increased by the fluorescence "invisible" lami_nae. In fact, the presence of a wide diversity of organic molecule in the calcite lead us to consider the fluorescence lamina as a temporal proxy controlled by the annual leaf fall and biopedological degradation. To measure these two proxies, an original experimental set has been developed in collaboration with the PhLAM laboratory (Lille, France). Particularly, this experimental set up permits to realise simultaneously a reflectance and a fluorescence image. The data collected are processed and are analysed in the frequency domain. All these data allow us to extract different proxies from speleothems. These proxies have been studied for some Vercors samples. We present the global environmental and climatic data archiving of the post_wurmian (isotopic stage 1) warming. At a higher resolution, the Vercors climate forcing is shown through the spectral analysis of the reflectance of a well laminated sample. The solar (T=22y) and atmospheric (NAO, T=17y) forcings are clearly distinguished. The climate analysis of this sample is limited by an anthropic mask. We show the similarity of the crystal facies evolution of two samples located around the Alps but far from more than 100 km. We would like to interpret this changes as an archiving of the post Little Ice Age warming but here too, Man interfere with climate to induce environmental changes. We show an example of the possibility for distinguishing climate from anthropic changes in environmental evolutions. The wealth of data of the speleothem allows us to appreciate the environ_ment stability of the Vercors which is confirmed in the spectral analysis of the growth rates of a Gouffre Berger sample. The diversity of the data collected in speleothems is directly linked to the diversity of the way of archiving in a karst system. It is why only a global approach seems to be relevant for answering environmental hydrological or morphological karst questions.

Growth and demise of an Archean carbonate platform, Steep Rock Lake, Ontario, Canada, 1999, Kusky T. P. , Hudleston P. J. ,
The Steep Rock Group of northwest Ontario's Wabigoon subprovince is one of the world's thickest Archean carbonate platform successions. It was deposited unconformably over a 3001-2928 Ma gneissic terrane, and contains a remarkable group of biogenic and oolitic limestones, dolostones, micrites, and karat breccias capped by a thick paleosol developed between and over karst towers. The presence of aragonite fans, herringbone calcite, and rare gypsum molds suggests that the carbonate platform experienced at least local anaerobic and hypersaline depositional conditions. This sequence shows that a combination of chemical and biological processes was able to build a carbonate platform 500 m thick by 3 billion years ago. The carbonate platform is structurally overlain by a mixture of complexly deformed rocks of the Dismal Ashrock forming a melange with blocks of ultramafic volcaniclastic rocks, mafic volcanics, carbonate, tonalite, lenses of Fe-ore rock, and metasedimentary rocks, in a shaly, serpentinitic, and fragmental ultramafic volcaniclastic matrix. The melange shows evidence of polyphase deformation, with early high-strain fabrics formed at amphibolite facies, and later superimposed brittle fabrics related to the final emplacement of the melange over the carbonate platform. An amphibolite- through greenschist-grade shear zone marks the upper contact of the melange with overlying mafic volcanic and tuffaceous rocks of the ca. 2932 Ma Witch Bay allochthon, interpreted as a primitive island are sequence. We suggest an evolutionary model for the area that begins with rifting of an are sequence (Marmion Complex of the Wabigoon are) that initiated subsidence and sedimentation on the Steep Rock platform and its correlatives that extend for a restored strike length exceeding 1000 km. Shallow water carbonate sedimentation continued until the platform was uplifted on the flanks of a flexural bulge related to the approach of the Witch Bay allochthon, representing collision of the rifted are margin of the Wabigoon subprovince with the Witch Bay are. Melange of the Dismal Ashrock was formed as off-axis volcanic rocks were accreted to the base of the Witch Bay allochthon prior to its collision with the Steep Rock platform

Carbonate platform systems: components and interactions -- an introduction, 2000, Insalaco Enzo, Skelton Peter, Palmer Tim J. ,
Carbonate platforms are open systems with natural boundaries in space and time. Across their spatial boundaries there are fluxes of energy (e.g. light, chemical energy in compounds, and kinetic energy in currents and mass flows) and matter (e.g. nutrients, dissolved gases such as CO2, and sediment -- especially, of course, carbonates). Internally, these fluxes are regulated by myriads of interactions and feedbacks (Masse 1995), and the residue is consigned to the geological record. The most distinctive aspect of carbonate platforms is the predominant role of organisms in producing, processing and/or trapping carbonate sediment, even in Precambrian examples. Because of evolutionary changes in this strong biotic input, it is harder to generalize about carbonate platforms than about most other sedimentary systems. Evolution has altered both the constructive and destructive effects of platform-dwelling organisms on carbonate fabrics, with profound consequences for facies development. Moreover, changing patterns in the provision of accommodation space (e.g. between greenhouse and icehouse climatic regimes) have also left their stamp on facies geometries, in turn feeding back to the evolution of the platform biotas. Hence simplistic analogies between modern and ancient platforms may give rise to misleading interpretations of what the latter were like and how they formed. Although a number of carbonate platform and reef specialists have warned of the dangers of such misplaced uniformitarianism (e.g. Braithwaite 1973; Gili et al. 1995; Wood 1999), it remains depressingly commonplace in the literature on ancient carbonate platforms. The endless quest in the literature for an allpurpose definition of reefs' ... This 250-word extract was created in the absence of an abstract

Calcite fabrics, growth mechanisms environments of formation in speleothems from the Italian Alps and southwestern Ireland., 2000, Frisia S. , Borsato A. , Fairchild I. J. , Mcdermott F.

Calcite Fabrics, Growth Mechanisms, and Environments of Formation in Speleothems from the Italian Alps and Southwestern Ireland, 2000, Frisia S, Borsato A, Fairchild Ij, Mcdermott F,
Five fabrics were identified in Alpine and Irish caves on the basis of morphological and microstructural characteristics, and related to growth mechanisms and growth environment. Columnar and fibrous fabrics grow when speleothems are continuously wet, and from fluids at near-equilibrium conditions (low supersaturation; SIcc < 0.35), through the screw dislocation mechanism. The highly defective microcrystalline fabrics form at the same supersaturation range as columnar fabric but under variable discharge and the presence of growth inhibitors. Dendritic fabrics, which have the highest density of crystal defects, develop in disequilibrium conditions (high supersaturation) under periodic very low-flow-regime periods that result in prolonged outgassing. Cave calcareous tufa forms in disequilibrium conditions. Only the calcite crystals of fabrics formed at low supersaturation seem to precipitate near-isotopic-equilibrium conditions

Lithological and structural controls of cave development, 2000, Klimchouk A. , Ford D.
This Chapter summarizes the important general controls that lithology and geologic structure impose on most cave genesis: rock purity, the presence of interbedded clastic rocks and adjacent or interbedded sequences of sulfates and carbonates, and various kinds of initial porosity, fissures in particular. Lithological and structural conditions for speleogenesis evolve throughout sedimentation, eogenesis, mesogenesis and telogenesis and change drastically between these stages. Inheritance in the evolution of different kinds of pre-speleogenetic porosity causes increasing heterogeneity in their distribution and parameters, which reaches the highest degree at the stage of rock emergence to the shallow subsurface and the surface after burial. The importance of fabric-selective porosity and stratigraphical elements diminishes with time in favor of fissure network porosity. Fissures evolve at different stages of the rock evolution. Networks are composed of complex planar and curvilinear surfaces interconnecting in three dimensions, constructed from fissures of various origins, generations and ages. The initial structural conditions for speleogenesis thus can be very varied depending on which particular stage speleogenesis commences. Conditions in deep-seated settings favor uniform speleogenetic development, while in shallow settings increased heterogeneity in fissure parameters can favor selective development. Modeling of conduit initiation and early development needs to take into account a great variability of initial permeability structures between common geological environments and evolutionary stages, especially rather dynamic non-dissolutional changes of these structures in shallow settings.

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