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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. ...

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. ...

Speleology in Kazakhstan

Shakalov on 11 Jul, 2012
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. ...

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That contamination is the addition to water of any substance or property preventing the use or reducing the usability of the water. there is no specific limits, since the degree of permissible contamination depends upon the intended end use, or uses, of the water [6]. sometimes considered synonymous with pollution.?

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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 coastal mixing zone (Keyword) returned 6 results for the whole karstbase:
Concepts and models of dolomitization: a critical reappraisal, 2004, Machel Hans G. ,
Despite intensive research over more than 200 years, the origin of dolomite, the mineral and the rock, remains subject to considerable controversy. This is partly because some of the chemical and/or hydrological conditions of dolomite formation are poorly understood, and because petrographic and geochemical data commonly permit more than one genetic interpretation. This paper is a summary and critical appraisal of the state of the art in dolomite research, highlighting its major advances and controversies, especially over the last 20-25 years. The thermodynamic conditions of dolomite formation have been known quite well since the 1970s, and the latest experimental studies essentially confirm earlier results. The kinetics of dolomite formation are still relatively poorly understood, however. The role of sulphate as an inhibitor to dolomite formation has been overrated. Sulphate appears to be an inhibitor only in relatively low-sulphate aqueous solutions, and probably only indirectly. In sulphate-rich solutions it may actually promote dolomite formation. Mass-balance calculations show that large water/rock ratios are required for extensive dolomitization and the formation of massive dolostones. This constraint necessitates advection, which is why all models for the genesis of massive dolostones are essentially hydrological models. The exceptions are environments where carbonate muds or limestones can be dolomitized via diffusion of magnesium from seawater rather than by advection. Replacement of shallow-water limestones, the most common form of dolomitization, results in a series of distinctive textures that form in a sequential manner with progressive degrees of dolomitization, i.e. matrix-selective replacement, overdolomitization, formation of vugs and moulds, emplacement of up to 20 vol% calcium sulphate in the case of seawater dolomitization, formation of two dolomite populations, and -- in the case of advanced burial -- formation of saddle dolomite. In addition, dolomite dissolution, including karstification, is to be expected in cases of influx of formation waters that are dilute, acidic, or both. Many dolostones, especially at greater depths, have higher porosities than limestones, and this may be the result of several processes, i.e. mole-per-mole replacement, dissolution of unreplaced calcite as part of the dolomitization process, dissolution of dolomite due to acidification of the pore waters, fluid mixing (mischungskorrosion), and thermochemical sulphate reduction. There also are several processes that destroy porosity, most commonly dolomite and calcium sulphate cementation. These processes vary in importance from place to place. For this reason, generalizations about the porosity and permeability development of dolostones are difficult, and these parameters have to be investigated on a case-by-case basis. A wide range of geochemical methods may be used to characterize dolomites and dolostones, and to decipher their origin. The most widely used methods are the analysis and interpretation of stable isotopes (O, C), Sr isotopes, trace elements, and fluid inclusions. Under favourable circumstances some of these parameters can be used to determine the direction of fluid flow during dolomitization. The extent of recrystallization in dolomites and dolostones is much disputed, yet extremely important for geochemical interpretations. Dolomites that originally form very close to the surface and from evaporitic brines tend to recrystallize with time and during burial. Those dolomites that originally form at several hundred to a few thousand metres depth commonly show little or no evidence of recrystallization. Traditionally, dolomitization models in near-surface and shallow diagenetic settings are defined and/or based on water chemistry, but on hydrology in burial diagenetic settings. In this paper, however, the various dolomite models are placed into appropriate diagenetic settings. Penecontemporaneous dolomites form almost syndepositionally as a normal consequence of the geochemical conditions prevailing in the environment of deposition. There are many such settings, and most commonly they form only a few per cent of microcrystalline dolomite(s). Many, if not most, penecontemporaneous dolomites appear to have formed through the mediation of microbes. Virtually all volumetrically large, replacive dolostone bodies are post-depositional and formed during some degree of burial. The viability of the many models for dolomitization in such settings is variable. Massive dolomitization by freshwater-seawater mixing is a myth. Mixing zones tend to form caves without or, at best, with very small amounts of dolomite. The role of coastal mixing zones with respect to dolomitization may be that of a hydrological pump for seawater dolomitization. Reflux dolomitization, most commonly by mesohaline brines that originated from seawater evaporation, is capable of pervasively dolomitizing entire carbonate platforms. However, the extent of dolomitization varies strongly with the extent and duration of evaporation and flooding, and with the subsurface permeability distribution. Complete dolomitization of carbonate platforms appears possible only under favourable circumstances. Similarly, thermal convection in open half-cells (Kohout convection), most commonly by seawater or slightly modified seawater, can form massive dolostones under favourable circumstances, whereas thermal convection in closed cells cannot. Compaction flow cannot form massive dolostones, unless it is funnelled, which may be more common than generally recognized. Neither topography driven flow nor tectonically induced ( squeegee-type') flow is likely to form massive dolostones, except under unusual circumstances. Hydrothermal dolomitization may occur in a variety of subsurface diagenetic settings, but has been significantly overrated. It commonly forms massive dolostones that are localized around faults, but regional or basin-wide dolomitization is not hydrothermal. The regionally extensive dolostones of the Bahamas (Cenozoic), western Canada and Ireland (Palaeozoic), and Israel (Mesozoic) probably formed from seawater that was pumped' through these sequences by thermal convection, reflux, funnelled compaction, or a combination thereof. For such platform settings flushed with seawater, geochemical data and numerical modelling suggest that most dolomites form(ed) at temperatures around 50-80 {degrees}C commensurate with depths of 500 to a maximum of 2000 m. The resulting dolostones can be classified both as seawater dolomites and as burial dolomites. This ambiguity is a consequence of the historical evolution of dolomite research

Solutional features and cave deposits related to hypogene speleogenetic processes in a littoral cave of Mallorca Island (western Mediterranean) , 2010, Fornó, S J. J. , Merino A. , Giné, S J. , Giné, S A. , Grà, Cia 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.


Solutional features and cave deposits related to hypogene speleogenetic processes in a littoral cave of Mallorca Island (western Mediterranean), 2011, 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.


CAVITATS SUBAQUTIQUES DE LA FRANJA LITORAL DE MALLORCA, 2011, 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.


LA COVA DES PAS DE VALLGORNERA (Llucmajor, Mallorca). LA CAVITAT DE MAJOR DESENVOLUPAMENT DE LES ILLES BALEARS, 2011, 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


Uplifted flank margin caves in telogenetic limestones in the Gulf of Orosei (Central-East Sardinia—Italy) and their palaeogeographic significance, 2015, D'angeli Ilenia Maria, Sanna Laura, Clazoni Claudio, De Waele Jo

Thiswork reports the results of geomorphological observations carried out in the coastal Fico Cave and surrounding areas (Baunei, Central East Sardinia) in the Gulf of Orosei. A tidal notch, generally believed to be of Eemian (MIS 5e) age, is barely visible at 8.5 above present sea level (asl), some metres below the main entrance of the cave. Old cave passages, now partially opened by cliff retreat and parallel to the coastline, are clearly visible at around 14 m asl and correspond to the main level of Fico Cave. Two more notches are located higher, at 22 and 50 m asl. Fico Cave itself is composed of at least 6 clearly distinguished more or less horizontal levels (−10 m below present sea level (bsl), and +14, +22, +40, +50, and +63 m asl), independent of the stratal dip, arguing for a sea-level, and hence, fresh-water lens control. Cave passages develop along main fractures more or less parallel to the coastline and never extend landward for more than 150 m, mostly ending blindly, or diminishing in their dimensions progressively landward. Most passages only contain clay deposits, lacking fluvial or marine sediments or typical fluvial erosion morphologies (i.e. scallops).

It is suggested from this body of evidence that Fico Cave was formed in the coastal mixing zone along major discontinuities during several Quaternary interglacial periods, when sea level was high and relatively stable for enough time to develop large dissolutional voids. The geomorphological observations indicate the main +14 m asl level of the cave to have formed during MIS 9, and was heavily reworked during MIS 5, while the higher levels are relative to older interglacial highstands that occurred between 1 Ma and 325 ka. The small active branch developed below present sea level has formed during MIS 7 (225 ka). These observations shed new light on the position of the MIS 5e highstand markers in this area of the coast, much higher than previously thought.


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