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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. ...

Did you know?

That compaction is a decrease in the volume of a mass of sediments from any cause. in general, compaction may be regarded as the decrease in the thickness of sediments, as a result of an increase in vertical compressive stress, and is synonymous with 'one-dimensional consolidation,' as used by engineers. the term compaction is applied both to the process and to the measured change in thickness. in thick fine-grained beds, compaction is a delayed process involving the slow escape of pore water and the gradual transfer of stress from neutral to effective. until sufficient time has passed for excess pore pressure to decrease to zero, measured values of compaction are transient [21]. see also compaction, residual; compaction, specific.?

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.
Engineering challenges in Karst, Stevanović, Zoran; Milanović, Petar
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Featured articles from other Geoscience Journals
Geochemical and mineralogical fingerprints to distinguish the exploited ferruginous mineralisations of Grotta della Monaca (Calabria, Italy), Dimuccio, L.A.; Rodrigues, N.; Larocca, F.; Pratas, J.; Amado, A.M.; Batista de Carvalho, L.A.
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
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Your search for phreatic (Keyword) returned 370 results for the whole karstbase:
Showing 1 to 15 of 370
The role of tributary mixing in chemical variations at a karst spring, Milandre, Switzerland, , Perrin J. , Jeannin P. Y. , Cornaton F. ,
SummarySolute concentration variations during flood events were investigated in a karst aquifer of the Swiss Jura. Observations were made at the spring, and at the three main subterraneous tributaries feeding the spring. A simple transient flow and transport numerical model was able to reproduce chemographs and hydrographs observed at the spring, as a result of a mixing of the concentration and discharge of the respective tributaries. Sensitivity analysis carried out with the model showed that it is possible to produce chemical variations at the spring even if all tributaries have constant (but different for each of them) solute concentrations. This process is called tributary mixing. The good match between observed and modelled curves indicate that, in the phreatic zone, tributary mixing is probably an important process that shapes spring chemographs. Chemical reactions and other mixing components (e.g. from low permeability volumes) have a limited influence.Dissolution-related (calcium, bicarbonate, specific conductance) and pollution-related parameters (nitrate, chloride, potassium) displayed slightly different behaviours: during moderate flood events, the former showed limited variations compared to the latter. During large flood events, both presented chemographs with significant changes. No significant event water participates in moderate flood events and tributary mixing will be the major process shaping chemographs. Variations are greater for parameters with higher spatial variability (e.g. pollution-related). Whereas for large flood events, the contribution of event water becomes significant and influences the chemographs of all the parameters. As a result, spring water vulnerability to an accidental pollution is low during moderate flood events and under base flow conditions. It strongly increases during large flood events, because event water contributes to the spring discharge

Recharge of Phreatic Aquifers in (Semi-)Arid Areas, ,
Groundwater use is of fundamental importance to meet the rapidly expanding urban, industrial and agricultural water requirements in (semi) arid areas. Quantifying the current rate of groundwater recharge and define its variability in space and time are thus prerequesites for efficient groundwater resource managment in these regions, where such resources are often the key to economic development. Attention focuses on recharge of phreatic aquifers, often the most readily-available and affordable source of water in (semi) arid regions. These aquifers are also the most susceptible to contamination, with the recharge rate determining their level of vulnerability. (Semi) arid zone recharge can be highly variable, the greater the aridity, the smaller and potentially more variable the natural flux. Its determination is an iterative process, involving progressive data collection and resource evaluation; there is also a need to use more than one technique to verify results. Direct, localised and indirect recharge mechanisms from a spectrum of known sources are addressed in the framework of recharge from precipitation, intermittant flow and permanent water bodies. The approach taken for each of these reflects the nature and current understanding of the processes involved. The volume also reviews current recharge estimation challenges, outlines recent developments and offers guidance for potential solutions.

Vadose and phreatic features of limestone caves, 1942, Bretz J. H

Phreatic Floor Slot in Model Cave, Nevada, 1954, Lange Arthur L. ,

Terminations of Passages in Appalachian Caves as Evidence for a Shallow Phreatic Origin, 1960, White, William B.

Corrosion by mixing of waters., 1964, Bogli Alfred
Karst caves are prior to all due to corrosion. According to the well-known formula a CO2 supply is always needed. This type of dissolution explains only the corrosion in free circulation and, under reserve, the one in pressure conducts in the vadose zone. All corrosion in the phreatic domain is excluded, except for some rare cases in the upper levels. The corrosion by mixing of waters of different content in bicarbonates is effective in the entire karst, from the lowermost to the uppermost parts. Also the corrosion due to the lowering of temperature and by mixing of waters at different temperature has to be take into account. Excpet for some exceptional cases (e.g. thermal waters), this effect is very reduced.

The presence of Bogidiella albertimagni Hertzog 1933 in Romania and some remarks on the European species of this Genus., 1965, Dancau Dan, Serban Eugne
Studying several Bogidiella individuals collected from the phreatic biotope of Cerna Valley (Oltenia region) using Karaman-Chappuis method, authors announce the presence of Bogidiella albertimagni Hertzog in Romania. After a description of the studied individuals, the authors talk about some problems concerning the taxonomic value of B. albertimagni and B. skopljensis Karaman (this second species being formerly known in Romania) and the validity of B. denticulata Mestrov described from Yugoslavia.

Phreatobiological researches II., 1965, Motas Constantin, Serban Eugne
The present note calls into question the opinion of different authors concerning the presence or lack of adult Niphargus near the phreatic table (superior layer of phreatic water) in zones prospected by Karaman-Chappuis method. Our investigations have proved the reason for which Niphargus adults were less frequent in the superior layer of the phreatic water is rather concerned with our investigation means; which are very approximate -, than with the ecological or ethological requirements of these animals. The assertion that the phreatic fauna performs downward migrations during the floods must be considered as doubtful. During floods it is impossible to dig into the alluvial deposits immediately near the stream, these being completely flooded; so, we are obliged to dig in regions more distant from the riverside, which are not flooded. It is well known that in this zone the biocoenosis contains always a greater number of phreatobius elements. One of the authors (C. Motas) introduce the terms: rithrobios; for the fauna inhabiting the epigean streams, phreatobios; for that inhabiting the phreatic water, and geobios; for the terrestrial world.

Murray Cave, Cooleman Plain, New South Wales, 1966, Jennings, J. N.

Murray Cave is an almost horizontal former outflow cave, which is now on the brink of inactivity. A heavily decorated upper branch functioned during the first outflow phase and the present inactive entrance succeeded it as the outlet point. Both are at the level of a low aggradational terrace of the North Branch of Cave Creek outside the cave; this probably belongs to a Pleistocene cold period. An undecorated lower branch provided the third phase outlet, which still functions occasionally when water rises up a water trap at the inner end of the main passage and flows along that passage into it. The entrance chamber has angular gravel fill due to frost shattering, which post-dates the development of the lower branch passage and belongs to a late Pleistocene cold period. Evidence of free surface stream action predominates in the cave but shallow phreatic conditions must have contributed to its development.


Further Remarks on the Big Hole, Near Braidwood, New South Wales, 1967, Jennings, J. N.

The new data from the Big Hole and its vicinity give some further support to the view maintained previously as to its origin, though an approach through water chemistry proved non-committal. Difficulties attaching to an origin by true phreatic solution of underlying limestone through circulations of groundwater of meteoric provenance remain however. Nevertheless, the possibility, not considered previously, that the Big Hole is due to hydrothermal solution in the manner of many collapse structures associated with uranium ore bodies in southwestern U.S.A. finds no support in the regional geology of the Shoalhaven valley, though it could produce features of the right dimensions. Previous lack of a complete parallel to the Big Hole has been removed by reference to the furnas of southern Brazil where a similar origin to the one proposed here is also inferred.


Drought and Murray Cave, Cooleman Plain, 1969, Jennings J. N. , Nankivell I. , Pratt C. , Curtis R. , Mendum J.

The drought culminating in 1967-68 opened water-traps in Murray Cave, thus permitting the re-exploration and survey in January 1968, of a further 1,000 feet of the main passage. Previous explorations, of which oral tradition persisted, are known to have taken place in 1902-3 and some details of the early visitors are presented. The characteristics of the extension are predominantly shallow phreatic in nature and about half of it episodically functioning in this way at the present time; the water-traps along it are inverted siphons in the strict sense and located at the sharpest changes in cave direction. The exploration limit consists of a rockfall beneath a doline, which appears, therefore, to be at least in part a collapse doline. Beneath two other dolines the cave has no sign of collapse, though tall avens reach towards the surface; these dolines are due to surface solution only. The forward part of the cave is overlain by a short, steep dry valley; the relationship between the two remains problematic but there is good reason not to regard the dry valley as the determinant of the cave's location. The evidence is now stronger for an earlier hypothesis that the cave was formerly the outflow cave of nearby River Cave, a perennially active stream cave. It also seems likely that the episodic activity of Murray Cave is due to flood overflow from River Cave. The hydrological regime of the cave is compared with precipitation records of the nearby stations. The episodic flow through the cave does not require an abnormally wet winter; it can follow fairly quickly after complete emptying of the water-traps and approaches an annual event. Draining of the water-traps is a much less frequent event, but whether a series of low rainfall years is necessary, or a single pronouncedly dry year is sufficient to achieve this, cannot be determined from available data. On either count, it seems probable that the cave opened up two or more times between the known occasions of 1902-3 and 1968 in the period 1909-53 when the cave was visited infrequently.


River Cave, Cooleman Plain, Kosciusko National Park, And Its Hydrological Relationships, 1969, Jennings, J. N.

River Cave is a Zwischenhohle (between-cave) in which the active river passage is reached through a former tributary stream passage from a dry valley. Now vadose in character, it is of gentle gradient, with some normally and some temporarily water-filled reaches of shallow phreatic nature. There is only a single level of development. Water tracing has confirmed previous inferences that it is mainly fed from the South Branch watersink, that its normal flow goes to the Blue Waterholes, the main rising of the Plain, and that there is flood overflow to Murray Cave, which is shown to have been formerly the normal outflow cave of the system. In the changeover from one outflow point (Vorfluter) to another, a shorter, steeper cave and longer surface course has been replaced by a longer cave of shorter gradient. Ev's Cave, a flood inflow cave of the South Branch, may also feed River Cave and Keith's Faint Cave is inferred to be part of the link between South Branch Sink and River Cave. It has the aspect of an early stage of vadose development from phreatic conditions. Previous interpretation of Glop Pot as a true phreatic relic is maintained in the light of new facts. Evidence is lacking with which to date the caves at all reliably. Glop Pot possibly belongs to a phase of surface planation of Tertiary age whereas the other caves are likely to be consequent on Pleistocene dissection. The tributary passage of River Cave and its associated dry valley may have lost their stream in the Holocene when Murray Cave became intermittent in action also. The Murray Cave event is due to subterranean piracy associated with rejuvenation whereas the loss of the tributary stream is probably in part due to increasing warmth and less effective precipitation.


The Origin and Development of Mullamullang Cave N37, Nullarbor Plain, Western Australia, 1970, Hunt, G. S.

Mullamullang Cave N37 is the longest and most complex cave on the Nullarbor Plain, Southern Australia. Unlike the other caves, it possesses extensive levels of phreatic solution tube passages which permit stronger inferences to be made on the development of the collapse passages constituting the bulk of Mullamullang Cave and other deep Nullarbor caves. These passages have been formed by collapse through overlying belts of solution tube networks along an elongated zone of cavitation in the limestone. Massive breakdown was probably initiated at depth within the zone, at least 50 feet below the present watertable level. Upward stoping of the collapse would have been facilitated by the higher network levels in the zone, such as the Ezam and Easter Extension. Channelling of groundwater flow under the Plain is suggested by the belt-like nature of the networks. An epiphreatic origin is proposed for the network levels though convincing morphological evidence is wanting. Eustatic changes in sea level have been of fundamental importance in the development of the multiple levels. Wetter periods in the past were probably important as little development is taking place under present-day dry conditions. Correlation of wetter periods with Pleistocene glacials would help explain the development of huge collapse passages, but such correlatien cannot be assumed on present evidence. Massive collapse and doline formation were followed by subaerial weathering and vadose activity which modified the cave - especially near the entrance. Correlation of levels in Mullamullang with those in other Nullarbor deep caves is attempted. However, Mullamullang Cave is unique probably due to the lithology of the Abrakurrie Limestone in which it is developed.


Studies on the Biology of Oligochaetes from the phreatic water of an exposeds gravel bed., 1971, Ladle Michael.
More than twenty species of oligochaeta belonging to the families Enchytraeidae, Naididae, Tubificidae and Lumbriculidae were found in the phreatic water of the river bank gravels. Psammoryctes barbatus, Rhyacodrilus coccineus and Styludrilus heringianus were found throughout the year, attaining maturity in the spring. These three species may be univoltine under these conditions. The family Naididae and a few species of Tubificidae show well marked seasons of abundance, chiefly in the summer and autumn.

The living environment of Stenasellus virei Dollfus, 1897 (Asellote troglobe Crustacean): preliminary results., 1971, Magniez Guy
Stenasellus virei is now known from 77 localities (caves, phreatic waters and underflow of some rivers) of the eastern Aquitanian basin, central and eastern Pyrenees, and of Spain. A classification of the different biotopes of the species is attempted herein, and some of their characteristics are summarily described. This cavernicolous species can now be viewed in a new light, as much ecological as systematic or biogeographic.

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