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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 glacial till is an unassorted mixture of glacial drift [16]. synonym: boulder clay; till.?

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Chemistry and Karst, White, William B.
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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 isotopic (Keyword) returned 276 results for the whole karstbase:
Showing 1 to 15 of 276
Speleothems and paleoglaciers, , Spotl Christoph, Mangini Augusto,
Ice and speleothems are widely regarded as mutually exclusive as the presence of liquid water is a fundamental prerequisite for speleothem deposition. Here we show that speleothems may form in caves overlain by a glacier, as long as the temperature in the cave is above freezing and the conduits are not completely flooded by melt water. Carbonate dissolution is accomplished via sulfide oxidation and the resultant speleothems show high [delta]13C values approaching and locally exceeding those of the parent host rock (lack of soil-derived biogenic C). The [delta]18O values reflect the isotopic composition of the melt water percolating into the karst fissure network and carry an atmospheric (temperature) signal, which is distinctly lower than those of speleothems formed during periods when soil and vegetation were present above the cave. These `subglacial' speleothems provide a means of identifying and dating the former presence of warm-based paleoglaciers and allow us to place some constraints on paleotemperature changes

Paleoclimate and location of the border between Mediterranean climate region and the Saharo-Arabian Desert as revealed by speleothems from the northern Negev Desert, Israel, , Vaks A. , Barmatthews M. , Ayalon A. , Matthews A. , Frumkin A. , Dayan U. , Halicz L. , Mogilabin A. , Schilman B. ,
Speleothem bearing karstic caves of the northern Negev Desert, southern Israel, provides an ideal site for reconstructing the paleoclimate and paleo-location of the border between Mediterranean climate region and the Saharo-Arabian Desert. Major periods of speleothem deposition (representing humid periods) were determined by high resolution 230Th-U dating and corresponding studies of stable isotope composition were used to identify the source of rainfall during humid periods and the vegetation type. Major humid intervals occurred during glacials at 190-150[no-break space]ka, 76-25[no-break space]ka, 23-13[no-break space]ka and interglacials at 200-190[no-break space]ka, 137-123[no-break space]ka and 84-77[no-break space]ka. The dominant rainfall source was the Eastern Mediterranean Sea, with a possible small contribution from southern tropical sources during the interglacial periods. When the interglacial interval rainfall was of Eastern Mediterranean origin, the minimum annual rainfall was ~ 300-350[no-break space]mm; approximately twice than of the present-day. Lower minimum amounts of precipitation could have occurred during glacial periods, due to the cooler temperatures and reduced evaporation. Although during most of the humid periods the vegetation remained steppe with mixed C3 C4 vegetation, Mediterranean C3 type steppe-forest vegetation invaded southward for short periods, and the climate in the northern Negev became closer to Mediterranean type than at present. The climate was similar to present, or even more arid, during intervals when speleothem deposition did not occur: 150-144[no-break space]ka, 141-140[no-break space]ka, 117-96[no-break space]ka, 92-85[no-break space]ka, 25-23[no-break space]ka, and 13[no-break space]ka-present-day.Precipitation increase occurred in the northern Negev during the interglacial monsoonal intensity maxima at 198[no-break space]ka, 127[no-break space]ka, 83[no-break space]ka and glacial monsoonal maxima at 176[no-break space]ka, 151[no-break space]ka, 61[no-break space]ka and 33[no-break space]ka. However, during interglacial monsoonal maxima at 105[no-break space]ka and 11[no-break space]ka, the northern Negev was arid whereas during glacial monsoonal minima it was usually humid. This implies that there is not always synchroneity between monsoonal activity and humidity in the region.Oxygen isotopic values of the northern Negev speleothems are systematically lower than contemporaneous speleothems of central and northern Israel. This part is attributed to the increased rainout of the heavy isotopes by Rayleigh fractionation processes, possibly due to the farther distance from the Mediterranean coast

Environmental isotopic and hydrochemical study of water in the karst aquifer and submarine springs of the Syrian coast, , Al C, Abdul R,

Isotopic variations in meteoric waters, 1961, Craig H.

The isotopic geochemistry of speleothems - I. The calculation of the effects of different modes of formation on the isotopic composition of speleothems and their applicability as palaeoclimatic indica, 1971, Hendy C. H.

Donnees geomorphologiques sur la region de Fresh Creek, Ile Andros (Bahama), 1974, Bourrouilh F,
A geomorphological study of the east coast of Andros (Fresh Creek area) shows the existence of a paleotopography represented by low-altitude hills (few metres). This paleotopography is protected by the presence of a calcitic Quaternary crust which covers Pleistocene calcarenite.In the western part of the area, there are long woody axes, oriented NE-SW, parallel to the channels of the creek. They end at two kilometres from the coast, along which is a second kind of lower hills, orthogonal to the first.The first axes can be interpreted as megaripples as seen at the present time on modern deposits (on the Great Bahama Bank) and fossilized by the upper crust. The second direction is made by accretion ripples along the coast.The surface of the Bahamian calcarenite has been studied. The Bahamian karst presents two topographical forms: “blue holes” like those outside the island, which are 60-80 m in diameter and both sparse and deep; and “washtub” dolines; these are numerous and shallow, and, from low altitude, exhibit a honeycombed aspect on the surface. This karstic topography with dolines and blue holes is also seen through the water of the Creek the hard bottom of which is covered only here and there with a few centimetres of sediments. Hence, there is a submerged karstic topography, made of the same elements as the aerial karst, but submerged by the Holocene transgression. The present karstic relief, in relation with the different eustatic levels of the Quaternary, has begun 120,000 years ago, according to the isotopic ages, and might be composed by different steps, difficult to show now, in the topography.The blue holes in the interior of the island of young and little evolved karst, were formed more by solution than by collapse of the karstic caves, because of the absence of a real river to drain the Andros shelf at the time of low sea levels. Blue holes of the inside of the island, as they are called, with submarine openings, have the same salinity as the water of the creek (17.5 g/l). The dolines with very low salinity (0.7 g/l to 3.8 g/l) are filled with stromatolites and charophytes, slowly forming sediments made up essentially of high-magnesian calcite.It seems that the Andros Island karst can be compared with that of the Yucatan, where there are round and deep open pits, called cenote, of which the Bahamian equivalent would be the blue holes which were drowned by the Holocene transgression.ResumeSur l'ile Andros, zone emergee du Grand Banc de Bahama, l'auteur montre l'existence d'une paleotopographie comprenant deux categories de rides d'orientation differente et semblant fossilisee par une croute calcitique recente et l'existence d'un karst aux formes jeunes, bien qu'heritage d'un karst holocene en voie de submersion. Ces formes sont des “blue holes” ou trous bleus circulaires (60 a 80 m de diametre) et peu nombreux, et des dolines, dites en baquet. Dans ces dolines se deposent actuellement des croutes stromatolithiques calcitiques dont l'etude est faite par diffractometrie de rayons X et microscopie electronique a balayage

Continental Pleistocene Climatic Variations from Speleothem Age and Isotopic Data, 1974, Thompson Peter, Schwarcz Henry P. , Ford Derek C. ,
Speleothems from continental North American caves have been dated by means of the 230Th/234U method. Oxygen isotopic variations in the dated samples and phases of speleothem deposition can be interpreted in terms of climatic change. A glacial chronology constructed from the age and isotopic data lends support to the astronomical theory of climatic change

Identification of the origin of oreforming solutions by the use of stable isotopes, 1977, Sheppard S. M. F. ,
SynopsisThe four major different types of water -- magmatic, metamorphic, sea water and/or connate, and meteoric water -- have characteristic hydrogen (D/H) and oxygen (18O/16O) isotope ratios. Applied to the analysis of isotopic data on hydrothermal minerals, fluid inclusions and waters from active geothermal systems, these ratios indicate that waters of several origins are involved with ore deposition in the volcanic and epizonal intrusive environment. Water of a single origin dominates main-stage mineralization in some deposits: magmatic -- Casapalca, Peru (Ag-Pb-Zn-Cu); meteoric -- Butte, Montana (Cu-Zn-Mn), epithermal deposits, e.g. Goldfield, Tonopah, Nevada (Ag-Au), Pachuca, Mexico (Ag-Au), San Juan Mountains District, Colorado (Ag-Au-Pb-Zn); sea water -- Troodos, Cyprus (Fe-Cu), Kuroko, Japan (Fe-Cu-Pb-Zn). Solutions of more than one origin are important in certain deposits (magmatic and meteoric -- porphyry copper and molybdenum deposits) and are present in many. In the porphyry Cu-Mo deposits the initial major ore transportation and alteration processes (K-feldspar-biotite alteration) are magmatic-hydrothermal events that occur at 750-500{degrees}C. These fluids are typically highly saline Na-K-Ca-Cl-rich brines (more than 15 wt % equivalent NaCl). The convecting meteoric-hydrothermal system that develops in the surrounding country rocks with relatively low integrated water/rock ratios (less than 0.5 atom % oxygen) subsequently collapses in on a waning magmatic-hydrothermal system at about 350-200{degrees}C. These fluids generally have moderate to low salinities (less than 15 wt % equivalent NaCl). Differences among these deposits are probably in part related to variations in the relative importance of the meteoric-hydrothermal versus the magmatic-hydrothermal events. The sulphur comes from the intrusion and possibly also from the country rocks. Deposits in which meteoric or sea water is the dominant constituent of the hydrothermal fluids come from epizonal intrusive and sub-oceanic environments where the volcanic country rocks are fractured or well jointed and highly permeable. Integrated water/rock ratios are typically high, with minimum values of 0.5 or higher (atom % oxygen) -- the magmatic water contribution is often drowned out'. Salinities are low to very low (less than 10 wt % equivalent NaCl), and temperatures are usually in the range 350-150{degrees}C. The intrusion supplies the energy to drive the large-scale convective circulation system. The sulphur comes from the intrusion, the country rocks and/or the sea water. Argillic alteration, which occurs to depths of several hundred metres, generated during supergene weathering in many of these deposits is isotopically distinguishable from hydrothermal clays

Cave and Landscape Evolution At Isaacs Creek, New South Wales, 1979, Connolly M. , Francis G.

Isaacs Creek Caves are situated in the Hunter Valley of New South Wales and form a distinct unit within the Timor karst region. The larger caves such as Man, Helictite and Belfry all show evidence of early development under sluggish phreatic conditions. Nevertheless later phases of dynamic phreatic and vadose development occurred in Belfry and Helictite caves. In the case of Helictite Cave sluggish phreatic, dynamic phreatic and vadose action may have operated simultaneously in different parts of the same cave. After each cave was drained through further valley incision by Isaacs Creek, extensive clay fills derived from surface soil were deposited in it. There has been considerable re-excavation of the fills; in Main Cave younger clay loams have partially filled the resulting cavities and thus underlie the older clays. The earliest speleogenesis took place in Main Cave which pre-dates the valley of Isaacs Creek. This cave now lies in the summit of Caves Ridge about 100m above the modern valley floor. Helictite and Shaft Caves formed when the valley had been cut down to within 30m of its present level and some early phreatic development also took place in the Belfry Cave at this time. Later phases of dynamic phreatic and vadose development in Belfry Cave occurred when the valley floor lay about 12m above its present level and can be correlated with river terraces at this height. Evidence from cave morphology, isotopic basalt dates and surfaces geomorphology indicates that Main Cave formed in the Cretaceous and that Helictite Cave, Shaft Cave and the early development in Belfry Cave date from the Palaeogene. Although the dynamic phreatic and vadose action in Belfry Cave is more recent, it may still range back into the Miocene. This is a much more ancient and extended chronology than has hitherto been proposed for limestone caves and is in conflict with widely accepted ideas about cave longevity. Nevertheless evidence from Isaacs Creek and other parts of the Hunter Valley indicates that the caves and landforms are ancient features and thus notions of cave longevity developed in younger geological environments of the northern hemisphere do not apply in the present context.


A possible mechanism for growth of calcite speleothems without participation of biogenic carbon dioxide, 1982, Dreybrodt W,
Using Plummer et al.'s [11] rate equations on the dissolution and deposition of CaCO3 in H2O---CO2 systems, we have calculated deposition rates of CaCO3 to stalagmites in caves which are covered by glaciers or bare karst. In this case no biogenic CO2 from vegetated soil is available and the deposition of CaCO3 involves only atmospheric CO2. The mechanism of deposition proceeds by a temperature effect. Cold melting waters of about 0[deg]C dissolve CaCO3 under open system conditions at the surface of the rock. When this solution saturated with respect to CaCO3, flows through the limestone rock its temperature increases by several degrees. Therefore, it becomes supersaturated, and CaCO3 is deposited under open system conditions in the warmer cave. Maximal growth rates of about 10-3 cm/year are possible. From the kinetics of the deposition of CaCO3 from the thin water films present at the surface of stalagmites we are able to estimate the isotopic composition of carbon in the CaCO3 deposited on the stalagmites to be approximately [delta]13C = %, which is close to some observed values.From our data we conclude that substantial growth of stalagmites is possible during glacial periods as well as in areas of bare karst, a question which was not resolved up to now

Isotopic composition of precipitation, cave drips and actively forming speleothems at three Tasmanian cave sites., 1982, Goede A. , Green D. C. , Harmon R. S.

Hydrogeological conditions in the Middle East, 1982, Burdon Dj,
The geology of Middle East is summarized under the subheadings: Precambrian basement, epicontinental sediments, geosynclinal and shelf deposits, Tertiary volcanics and Quaternary cover. The main tectonic episodes including epeirogenic movements, rifting and the Tertiary orogeny, are reviewed. The imposition of hydrometeorolocal and climatic conditions upon the regional geology provides the setting for the hydrogeological discussion. Five factors which influence infiltration to aquifers under conditions of low precipitation and high potential evaportranspiration are discussed. The predominance of fossil groundwater is the most striking hydrogeological phenomenon occurring on a regional scale in the Middle East. Its mode of formation during the pluvials is outlined and the isotopic evidence is reviewed. The main physical and chemical characteristics of fossil ground-waters are described. It is conservatively estimated that some 65 000 km3 of good- to medium-quality groundwater are stored in the great artesian basins of the Near East. These fossil ground-waters are a non-renewable natural resource. Current annual abstraction is, as yet, a small percentage of the total reserves but economic factors rather than the volume of reserves will determine the ultimate extent of their exploitation. The renewable groundwater resources of the Middle East tend, by comparison, to be of local rather than regional significance. Some originate outside the Middle East, coming in as surface flows in the Nile and Tigris-Euphrates and infiltrating into the sediments in and adjacent to the flood plains. Other renewable resources accumulate within the region where high precipitation and mountainous relief are associated. Such areas include the Djebel Akhdar of Cyrenacia, the Tertiary fold mountains from the Taurus through the Zagros to the Oman ranges, and the volcanic and basement highlands of Yemen, Asir and Ethiopa. Locally, in areas of lower precipitation, lenses of recent fresh groundwater float on regional more saline groundwater. In some areas subsurface flows towards and through wadi systems are also of importance

Isotopic Composition of Precipitation, Cave Drips and Actively Forming Speleothems at Three Tasmanian Cave Sites, 1982, Goede A. , Green D. C. , Harmon R. S.

Monthly samples of precipitation and cave drips were collected from three Tasmanian cave sites along a north-south transect and their 18O/16O ratios determined. At one station D/H ratios were also measured and the relationship between delta 18O and delta D values investigated. The 18O/16O and D/H ratios of monthly precipitation show marked seasonality with values correlating strongly with mean monthly temperatures. The effect of temperature on 18O/16O ratios appears to increase as one goes southwards and is at least twice as strong at Hastings (.61 deg /oo SMOW/ deg C) as it is shown at Mole Creek (.28 deg /oo SMOW/ deg C). Irregularities in the seasonal pattern of 18O/16O change are particularly pronounced at Hastings and in the Florentine Valley and can be attributed to the amount effect. For delta 18O values > -5.5 deg /oo the combined data from the three Tasmanian stations show an amount effect of .026 deg /oo SMOW/mm. Cave drips show apparently random, non-seasonal variation in the 18O / 16O isotopic compostion but the weighted mean of the 18O/16O isotope composition of precipitation provides a good approximation to their mean 18O/16O isotopic composition. In contrast to their D/H ratios for a cave drip site in Little Trimmer Cave, Mole Creek, show a distict seasonal pattern. The 18O/16O and 13C/12C ratios have been determined for a number of actively forming speleothems. With respect to 18O/16O it is found that speleothems the three sites are being deposited under conditions approaching isotopic equilibrium. The 13C/12C ratios of these speleothems are highly variable but the generally less negative values found in Frankcombe Cave (Florentine Valley) compared with the other two sites may reflect the effects of recent clearfelling in the area.


Etudes rcentes sur le karst de Niaux-Lombrive-Sabart (Arige), 1983, Renault, Ph.
RECENT INVESTIGATIONS ABOUT THE NIAUx-LOMBRiVE-SABART KARST (Arige, France) - Several recent investigations concerne this important system (14km). The P. Sorriaux sedimentologi-cal thesis (1982) establishes that the ancient troughflows have inverted their direction during an evolution of at least 400,000 years (isotopic dating from calcite) under glacial conditions. The C. Andrieux, J. Brunet and Ph. Renault speleometeorological studies (1974-1983) concerning the thermic equilibrium pattern and the carbon dioxide distribution suggest an atmospheric model. The closing or opening of some the locks (sumps, doors) induces the changing of a barometric causality into a thermic one with the production of a general air flow.

The stable isotopic composition of modern soil carbonate and its relationship to climate, 1984, Cerling O. A.

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