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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 flexure is a bend in a stratum with one flank or limb only [16].?

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.
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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 reef (Keyword) returned 102 results for the whole karstbase:
Showing 91 to 102 of 102
Solutional features and cave deposits related to hypogene speleogenetic processes in a littoral cave of Mallorca Island (western Mediterranean), 2011,
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Fornos J. J. , Merino . , Gines A. , Gracia F.

The Cova des Pas de Vallgornera, located in the southern part of Mallorca Island (western Mediterranean) and developed in Upper Miocene reefal carbonate limestones, is an exceptional coastal cave because of its particular morphological features and the presence of
deposits with uncommon mineralogies. Littoral mixing dissolution processes represent the most important speleogenetic mechanism to be considered in the eogenetic karst platform, where it develops; nevertheless, part of the cave consists of an extensive network of galleries that show morpho-sedimentary features pointing up to a possible participation of hypogene speleogenesis. The morphological
assemblage of the cave illustrates besides the typical coastal karstification, a noticeable meteoric water recharge along with a possible deep recharge of hypogenic character. Features consisting in upwards solutional channels are abundant, including a complete morphologic suite of rising flow supporting the involvement of hypogene speleogenetic
processes. Furthermore, the presence of vents and some related speleothems, such as crusts and cave rims, together with Mn and Fe-rich deposits hosting several minerals not observed until present in other caves of the region must be highlighted. Given the monotonous surface
geology around the cave, it is suspected that ascending Sr, Ba, Mn, and Al-rich hypogene solutions may have reacted with the host rock to form this unique mineral assemblage.  These deep-seated speleogenetic and mineralogical phenomena could be associated with the feeble geothermal anomalies existing currently in the Llucmajor platform,
related to SW–NE faults which delimitate the subsidence basin existing in the southern end of Mallorca Island.

Geochemical/isotopic evolution of Pb-Zn deposits in the Central and Eastern Taurides, Turkey, 2011,
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Hanilci N. , Ozturk H.

The Central and Eastern Taurides contain numerous carbonate-hosted Pb-Zn deposits, mainly in Devonian and Permian dolomitized reefal-stramatolitic limestones, and in massive Jurassic limestones. We present and compare new fluid inclusion and isotopic data from these ore deposits, and propose for the first time a Mississippi Valley-type (MVT) mode of origin for them. Fluid inclusion studies reveal that the ore fluids were highly saline (13-26% NaCl equiv.), chloride-rich (CaCl2) brines, and have average homogenization temperatures of 112°C, 174.5°C, and 211°C for the Celal Dag, Delikkaya, and Ayrakl deposits, respectively. Furthermore, the ?34S values of carbonate-hosted Pb-Zn deposits in the Central and Eastern Taurides vary between -5.4‰ and +13.70‰. This indicates a possible source of sulphur from both organic compounds and crustal materials. In contrast, stable sulphur isotope data (average ?34S -0.15‰) for the Cadrkaya deposit, which is related to a late Eocene-Oligocene (?) granodioritic intrusion, indicates a magmatic source. The lead isotope ratios of galena for all investigated deposits are heterogeneous. In particular, with the exception of the Sucat district, all deposits in the Eastern (Delikkaya, Ayrakl, Denizovas, Cadrkaya) and Central (Katranbasi, Kucuksu) Taurides have high radiogenic lead isotope values (206Pb/204Pb between 19.058 and 18.622; 207Pb/204Pb between 16.058 and 15.568; and 208Pb/204Pb between 39.869 and 38.748), typical of the upper continental crust and orogenic belts. Fluid inclusion, stable sulphur, and radiogenic lead isotope studies indicate that carbonate-hosted metal deposits in the Eastern (except for the Cadrkaya deposit) and the Central Taurides are similar to MVT Pb-Zn deposits described elsewhere. The primary MVT deposits are associated with the Late Cretaceous-Palaeocene closure of the Tethyan Ocean, and formed during the transition from an extensional to a compressional regime. Palaeogene nappes that typically limit the exposure of ore bodies indicate a pre-Palaeocene age of ore formation. Host rock lithology, ore mineralogy, fluid inclusion, and sulphur + lead isotope data indicate that the metals were most probably leached from a crustal source such as clastic rocks or a crystalline massif, and transported by chloride-rich hydrothermal solutions to the site of deposition. Localization of the ore deposits on autochthonous basement highs indicates long-term basinal fluid migration, characteristic of MVT depositional processes. The primary MVT ores were oxidized in the Miocene, resulting in deposition of Zn-carbonate and Pb-sulphate-carbonate during karstification. The ores underwent multiple cycles of oxidation and, in places, were re-deposited to form clastic deposits. Modified deposits resemble the 'wall-rock replacement' and the 'residual and karst fill' of non-sulphide zinc deposits and are predominantly composed of smithsonite

Formation and accumulation of oil and gas in marine carbonate sequences in Chinese sedimentary basins, 2011,
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Jin, Z.

Advances in studies of formation and accumulation mechanisms of oil and gas in marine carbonate sequences have led to continuing breakthroughs of petroleum exploration in marine carbonate sequences in Chinese sedimentary basins in recent years. The recently discovered giant Tahe Oil Field and Puguang Gas Field have provided geological entities for further studies of the formation and accumulation of oil and gas in marine carbonate sequences. Marine carbonate sequences in China are characterized by old age, multiple structural deformation, differential thermal evolution of source rocks, various reservoir types (i.e. reef-bank complex and paleo-weathered crust karst reservoir), uneven development of caprocks, especially gypsum seal, and multi-episodes of hydrocarbon accumulation and readjustment. As a result, the formation of hydrocarbon accumulations in the Chinese marine carbonate sequences has the following features: (i) the high-quality marine source rocks of shale and calcareous mudstone are often associated with siliceous rocks or calcareous rocks and were deposited in slope environments. They are rich in organic matter, have a higher hydrocarbon generation potential, but experienced variable thermal evolutions in different basins or different areas of the same basin. (ii) High quality reservoirs are controlled by both primary depositional environments and later modifications including diagenetic modifications, structural deformations, and fluid effects. (iii) Development of high-quality caprocks, especially gypsum seals, is the key to the formation of large- and medium-sized oil and gas fields in marine carbonate sequences. Gypsum often constitutes the caprock for most of large sized gas fields. Given that Chinese marine carbonate sequences are of old age and subject to multiple episodes of structural deformation and superposition, oil and gas tend to accumulate in the slopes and structural hinge zones, since the slopes favor the development of effective assemblage of source-reservoir-caprock, high quality source rocks, good reservoirs such as reef-bank complex, and various caprocks. As the structural hinge zones lay in the focus area of petroleum migration and experienced little structural deformation, they are also favorable places for hydrocarbon accumulation and preservation.

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Forns J. J. , Gelabert B.

The lithology and structural setting of the rocks which form the island of Mallorca are magnificent bases on which karstic phenomena develop. Almost every geological period is continually represented here, from the Carboniferous to the Pleistocene (only part of the Upper Cretaceous and Lower Paleogene being absent). The approximate thickness of the stratigraphic sequence is 3,000 m in which carbonate deposits (not only limestones but also dolomites) constitute the most important lithologies. The main structure consists of thrust sheets imbricated in a NW transport direction. Such deformation took place during the alpine orogeny. Furthermore, the existence of impervious materials from the Keuper at the base of the thrust sheets, added to the imbricate thrusts system structure, cause permeable zones to remain isolated by areas of impervious material. The development during the post-orogenic phase (Late Miocene) of a carbonate reef deposition, forms a large tabular slab where the phenomena related to coastal karst have its maximum expression. Menorca, can be divided into two very distinct parts. The northern half or Tramuntana, well structured, but dominated by the presence of siliceous material from the Devonian with a couple of large slabs of Mesozoic limestones and dolomites, quite different from Migjorn, in the south, where the Late Miocene calcarenites and calcisiltites clearly dominate. Eivissa can be assimilated to the same structure of the Tramuntana mountains of Mallorca, which are almost exclusively dominated by carbonate materials, particularly the dolomites, but the limestones from the middle Triassic and the marls (Cretaceous and lower Miocene) are very abundant. Formentera is dominated at both ends of the island by sea cliffs cut on Miocene reefal limestones joined by an isthmus where Pleistocene aeolian calcarenites outcrops.

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Grcia F. , Clamor B. , Gamund P. , Forns J. J. , Watkinson P.

The explorations in the caves with underwater extensions, existing along the littoral fringe of Mallorca Island, are firstly documented in 1972 due to the activities of Catalan cavers. During the end of 1980 decade and the early 1990 different campaigns were conducted by British cave divers. The year 1994 is formed the embryo of what would be, years later, the Diving Section of Grup Nord de Mallorca, a team of young Mallorcan cavers dedicated to the investigation of underwater cavities. The fruits of these researches have involved the exploration of the most extensive cave systems of the island, placing the underwater cavities of Mallorca at a remarkable position regarding coastal caves in Spain and in Europe. The cavities of littoral areas can be divided into: caves of the coastal mixing zone, littoral phreatic networks with hypogenic influences, and marine-karstic captures. Most of the caves are located in the littoral eogenetic karst developed within the post-orogenic platform of southern and eastern Mallorca, the so-called Migjorn karst region. The lithological conditionings have a decisive influence on the morphological features of the investigated caves. So, while in the front-reef facies of the Upper Miocene the collapse morphologies are dominant, related to the extensive dissolution of coral buildings, in the facies corresponding to lagoon environments the permeability associated to fractures becomes more important, due to the significantly lower rock porosity of these back-reef facies. The 12 most important caves have been selected, which are mainly located in the eastern coast of Mallorca (10). Regarding their distribution in the municipalities, Manacor (6) is the best represented, followed by Felanitx (3). The data corresponding to each cave, always subject to the availability of information, is structured in different sections: toponymy, geographical and geological location, history of explorations, cave description, hydrology, sediments, speleogenesis and evolutionary stage, paleontology, aquatic fauna and archeology.

Morfologies de corrosio de la zona de mescla a les cavitats subaquatiques de la franja litoral del Llevant i Migjorn de Mallorca, 2011,
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Gracia F. , Clamor B. , Gamundi P. , Fornos J. J.

In Mallorca Island,  the genesis of caves and  solutional  morphologies that characterize the eogenetic endokarst of the littoral fringe attain particular  intensity within the Upper Miocene  carbonate rocks.  Dissolution processes occur preferentially  in the  mixing zone  between freshwater –of meteoric  origin– and  marine  waters, all along  the  coastal areas. The submerged passages and  chambers, existing  in the caves of Migjorn and  Llevant regions  of the island, show a high diversity of solutional  features that are  categorized into four groups  according to their dimensions, the forms they present and the genetic  processes involved. The resulting morphologies are conditioned by the existence of significant lithological differences, of textural character, within the Upper Miocene  calcarenites where  caves develop, due  to environmental variations  between the reef front facies  and  those  corresponding to lagoon  facies.  The difficul­ ties encountered when cataloguing and systematizing the primary morphologies should  be, so often, attributed  to the difficulty in ascribing solutional features to a certain typology, as there are juxtapositions of different classes, with inter­ mediate forms and different degrees of intensity in the process of dissolution.  At the same time, variations  in the size of solutional morphologies also increase their difficulty of classification. The inventory of forms has been structured into 4 different categories: megaforms (organization of the  cave  systems), macroforms (morphologies from hectometric to decametric order), mesoforms (morphologies from decametric to metric order) and microforms (morphologies from metric by centimetric  order). Some  of the morphologies can be found simultaneously in two different categories.

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Merino A. , Mulet A. , Mulet G. , Croix A. , Kristofersson A. , Grcia F, Gins J. , Forns J. J.

Cova des Pas de Vallgornera is located in the Llucmajor municipality, Mallorca island, being the longest cave in the Balearic archipelago: currently its surveyed length is over 65.000 metres. It is a really unique cave within the endokarst of the Migjorn region of the island, not only because its development but also for the great deal of uncommon speleothems and solution morphologies. Regarding geological and geomorphologic aspects, this exceptional site clearly shows a very strong control imposed by the lithologic factors –the architecture of the Upper Miocene reef– on the pattern and the morphological features of the system. Furthermore, the cave supplies evidences of a multi-folded speleogenesis that includes besides the coastal mixing zone dissolution, a noticeable epigenic recharge as well as a possible basal recharge of hypogenic origin. All this together, makes the cave certainly outstanding even at an international level. The cave is under the protection of Conselleria de Medi Ambient, Govern de les Illes Balears (the Regional Environmental Authority) and was declared Site of Community Importance, within the Natura 2000 Network (European Council Directive 92/43/EEC). Access to the cave is highly restricted and only surveying and investigation tasks are authorized by the Regional Authority

Lechuguilla Cave, New Mexico, U.S.A., 2012,
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Kambesis, Patricia

Lechuguilla Cave in Carlsbad Caverns National Park, Guadalupe Mountains, New Mexico, has a 2010 surveyed length of 130 km. It is a hypogene cave, formed by uprising H2S-bearing fluids which oxidize to form sulfuric acid when they reach oxygen-bearing meteoric water. The cave is formed in the Permian Capitan Reef Complex. Argon-argon dating suggests that the cave is on the order of 5 million years old. Lechuguilla Cave exhibits dramatic mineralization, particularly gypsum chandeliers, native sulfur, and many massive calcite speleothems. Of particular interest is the microbiology of the cave where microbes, present and past, formed without surface interactions.

Karst hierarchical flow systems in the Western Cordillera of North America, 2013,
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Ford, Derek

By definition, karstic flow systems are networks of solutional conduits. Their spatial patterns and hierarchical organisation are strongly affected by differing lithology and geologic structure, and by the location and modes of recharge – unconfined, confined, interformational. For purposes of discussion, this paper will review six examples rang-ing across platform and reefal limestones and dolostones, dolostone breccias, gypsum and salt, in widely differing structural, geomorphic and hydrologic settings: (1) The Carcajou River karst at Lat. 65° N in the Mackenzie Mountains, where leaky permafrost superimposes a frozen ground hierarchy on those due to lithology, structure and topog-raphy: (2) The S Nahanni River karst at Lat. 62° N, with an intrusive-derived local thermal system and lengthy, strike-oriented meteoric flow systems that contribute to an outlet H2S thermal system at the basin topographic low: (3) Castleguard Mountain Karst (Lat. 52° N) in massive Main Ranges structures of the Rocky Mountains, with a complex alpine hierarchy of base-flow and overflow springs: (4) Crowsnest Pass, in steep thrust structures in the Rocky Mountain Front Ranges, where regional strike-oriented flow systems extending between Lats. 49° and 50° N and paired above and below a major aquitard have been disaggregated by glacial cirque incision: (5) The Black Hills geologic dome at Lat. 44° N in South Dakota, USA, with a sequence of hot springs at low points around the perimeter, discharging through sandstones but with some of the world’s most extensive hypogene maze caves formed in a limestone karst barré setting behind them: (6) The Sierra de El Abra, at Lat. 23° N in Mexico, a deep and lengthy (100 km) reef-backreef limestone range being progressively exposed and karstified by stripping of a cover of clastic rocks; the springs are few but amongst the largest known in karst anywhere, located at the northern and southern low extremities along the strike of the reef, plus breaches (windows) in the cover further south.

Geologic constraints and speleogenesis of Cova des Pas de Vallgornera, a complex coastal cave from Mallorca Island (Western Mediterranean), 2014,
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Ginés J. , Fornós J. J. , Ginés A. , Merino A. , Gràcia F.

The flat areas of eastern and southern Mallorca host a remarkable coastal karst, where Cova des Pas de Vallgornera stands out due to its length (more than 74 km) and its special morphological suite. The pattern of the cave is quite heterogeneous showing sharp differences produced by the architecture of the Upper Miocene reef: spongework mazes and collapse chambers dominate in the reef front facies, whereas joint-guided conduits are the rule in the back reef carbonates. Regarding the speleogenesis of the system, a complex situation is envisaged involving three main agents: coastal mixing dissolution, drainage of meteoric diffuse recharge, and hypogene basal recharge related to local geothermal phenomena. The cave system is disposed in two main tiers of passages, of which geomorphologic interpretations are derived from their elevation data. The evolutionary trends as well as the chronology of the different cave sections are difficult to establish owing to the frequent shifting of the coastal base level during the Plio-Quaternary. In this respect, the genesis and evolution of the cave were fully controlled by sea-level fluctuations in the Western Mediterranean basin, with the main phases of cave formation, based on vertebrate paleontological data, going back to mid-Pliocene times.

Speleothems in Cova des Pas de Vallgornera: their distribution and characteristics within an extensive coastal cave from the eogenetic karst of southern Mallorca (Western Mediterranean)., 2014,
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Merino A. , Ginés J. , Tuccimei P. , Soligo M. , Fornós J. J.

The abundance and variety of speleothems are undoubtedly among the remarkable features of Cova des Pas de Vallgornera, the longest cave system in Mallorca Island developed in the eogenetic karst of its southern coast. Due to the monotonous carbonate lithology of the area, most of the speleothems are composed of calcite and in a few cases aragonite, although other minerals are also represented (e.g., gypsum, celestine, barite.). However, in spite of the rather common mineralogy of the speleothems, its distribution results strongly mediated by the lithologic and textural variability linked to the architecture of the Upper Miocene reefal rocks. Apart from a vast majority of speleothem typologies that are ubiquitous all along the cave system, some particular types are restricted to specific sections of the cave. In its landward inner passages, formed in the low permeability back reef facies, a great variety of speleothems associated to perched freshwater accumulations stands out, as well as some non frequent crystallizations like for example cave rims. On the other hand, the seaward part of the cave (developed in the very porous reef front facies) hosts conspicuous phreatic overgrowths on speleothems (POS), which are discussed to show their applications to constrain sea level changes. The factors controlling the distribution of speleothems found in Cova des Pas de Vallgornera are discussed along the paper, focusing the attention on the lithologic, hydrogeologic and speleogenetic conditionings; at the same time some uncommon speleothems, not found in any other cave in Mallorca, are also documented from this locality. Finally, a cognizant endeavour has been undertaken to illustrate with photographs the most remarkable speleothem types represented in the cave.

Linking mineral deposits to speleogenetic processes in Cova des Pas de Vallgornera (Mallorca, Spain)., 2014,
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Onac B. P. , Fornós J. J. , Merino A. , Ginés J. , Diehl J.

Cova des Pas de Vallgornera (CPV) is the premier cave of the Balearic Archipelago. Over 74 km of passages develop within two carbonate lithofacies (reef front and back reef), which ultimately control the patterns of the cave and to some degree its mineral infilling. The diversity of speleothem-forming minerals is four times greater around or within hypogene-related features (vents, rims, cupolas), compared to any other vadose passages in the cave. The mineralogy of speleothems (crusts, nodules, crystals, earthy masses) associated with hypogene features in the seaward upper maze of Sector F is characterized by the presence of aragonite, ankerite, huntite, clay minerals, and quartz. In the Tragus and Nord sectors, however, the dominant mineral is dolomite, along with aragonite, celestine, huntite, clay minerals, and quartz. Calcite is by far the most ubiquitous mineral throughout the cave. Detailed macroscopic and scanning electron microanalysis and imaging have permitted the investigation of textural relationships between the minerals associated with vents, rims, and vent’s roof and walls. These studies along with morphological and stable isotope analyses confirm that not all minerals are connected with a hypogene stage in the cave evolution, and furthermore, none of them appears to be sulfuric acid by-products. Instead, the mineral assemblages documented in speleothems from CPV clearly support at least three speleogenetic pathways, namely seacoast mixing, ascending of warm groundwaters, and meteoric recharge (vadose). Thus, cave minerals in Cova des Pas de Vallgornera hold the keys to reconstruction and understanding of processes and conditions under which they precipitated, allowing to establish their relationship with various speleogenetic pathways

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