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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 dolomitic flour (sand) is a loose mealy rock or residuum, produced by the disintegration of dolomitic limestones under the processes of karstification [20]. synonyms: (french.) sable dolomitique; (german.) dolomitsand, dolomitasche; (greek.) dholomitikon alevron; (spanish.) arena dolomitica; (turkish.) dolomit kumu; (yugoslavian.) dolomitni pijesak, d. pesak, d. pesek.?

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 oxygen isotope (Keyword) returned 78 results for the whole karstbase:
Showing 1 to 15 of 78
The marine oxygen isotope record in Pleistocene coral, Barbados, West Indies, 1978, Fairbanks R. G. , Matthews R. K.

Oxygen isotopes and sea level, 1986, Chappell J. , Shackleton N. J.

La karstification de l'le haute carbonate de Makatea (Polynsie franaise) et les cycles eustatiques et climatiques quaternaires, 1991, Dessay J. , Pouchan Y. , Girou A. , Humbert L. , Malezieux J.
THE KARST 0F MAKATEA ISLAND (FRENCH POLYNESIA) AND THE CLIMATIC AND GLACIO-EUSTATISM SETTING - Located in the Central Pacific, in the northwestern part of the Tuamotu Archipelago, Makatea island (148 15 W - 15 50 S) is an uplifted, karstic, carbonate construction of Early Miocene age, which reaches 113m in height. From 1906 to 1966, phosphate deposits were exploited on Makatea Island. These phosphate deposits (apatite) overlaid the Miocene series and filled the karstic cavities in the higher regions of the island. Several traces of ancient shorelines can be observed on Makatea: 1/ three different reef formations, which reach about +27m, +7m, +1m above the present mean sea level and respectively dated 400,000 100,000 yr BP, 140,000 30,000 yr BP, between 4,470 150 yr BP and 3,720 13O yr BP; 2/ four distinct marine notch lines on the Early Miocene cliff at about +1m, +7m, +27m and +56m (or +47m on the west coast caused by tilt) above the present mean sea level; 3/ two exposed marine platforms respectively at +29m and +7m above the present mean sea level. The ages of the former makatean shores are inferred by using: (1) the Pacific glacio-eustatic sea-level curve for the last 140,000 yr BP, (2) the Pacific oxygen isotope curve for the last 900,000 yr BP, and (3) a constant uplift rate during the Pleistocene. In this way, according to their age and elevation, the sea-level indicators at about +1m, +7m and +27m (+29m) above the present mean sea level can be respectively related to the Holocene transgression (Flandrian) dated between 6,000 and 1,500 yr BP, to the last Pleistocene interglacial period (Sangamon) dated between about 130,000 and 110,000 yr BP, and to a Middle Pleistocene interglacial period (Yarmouth) dated between about 315,000 and 485,000 yr BP. If we assume that a sea level similar to the present occurred during the Yarmouth inter-glacial period, the uplift rate is valued at 0.085 mm/yr to 0.056 mm/yr. Thus the sea-level associated with the marine notch at about +56m (+47m) may be about 650,000 yr to 1 M.y. old and can be associated with another Pleistocene interglacial period (Aftonian). Consequently, as indicated by the former shores, the sea level fluctuations can be related to the major glacio-eustatic quaternary events. This climatic and eustatic setting is used to explain the karst observed on the Makatea island. Carbonate dissolution and essentially vertical karst genesis were the result of the superposition of several cycles. Each cycle was initially composed of a solution of the carbonates during an interglacial period, followed by a drainage of the saturated solutions during the marine regression associated with the consecutive glacial period. Nevertheless, this scheme is not enough to explain the specific morphology of the makatean karstic cavities and we suggest using insular phosphatisation to explain this karst genesis. It is generally accepted that phosphate rock deposits on coral reef islands are the result of chemical reaction between seabird guano and reef limestone. Furthermore, petrographic and stable isotope studies suggest several generations of phosphorite formation and reworking episodes in the history of these deposits. The primary deposition of phosphates must have begun during a glacial period. This deposition was followed by some redistribution of phosphorites during the interglacial period and by additional precipitation of apatite from meteoric waters. This assumed process of phosphogenesis is consistent with both the field observations and the geodynamic evolution of Makatea. Thus, the particular morphology of the makatean karst can be the result of the dissolution of the carbonates caused by phosphoric acid etching. This acid is derived from the evolution of the phosphorites during the pleistocene interglacial periods.

Oxygen isotopes in meteoric calcite cement as indicators of continental paleoclimate., 1991, Hays P. D. , Grossman E. L.

Correlated strontium, carbon and oxygen isotopes in carbonate gangue at the Nanisivik zinc-lead deposits, northern Baffin Island, Canada., 1992, Ghazban F. , Schwarcz H. P. , Ford D. C.

Several kinds of base metal deposits occur in the lower Paleozoic of southwest Sardinia (Iglesiente-Sulcis mineral district). This paper deals with those deposits which are generally referred to as Permo-Triassic, because they accompany and postdate the Hercynian orogeny and are related to magmatic activity. A large number of previously published geochemical data, integrated with additional new data (Sr, Pb, O, C, and S isotopes), are reviewed and discussed in the frame of the late to post-Hercynian geologic evolution of southwest Sardinia. According to geological and mineralogical characteristics, three types of deposits can be distinguished: (1) skarn ores related to late Hercynian leucogranitic intrusions, (2) high-temperature veins, and (3) low-temperature veins and karst filling. Pervasive epigenetic dolomitization phenomena are geochemically related to the low-temperature deposits. Sr and Pb isotopes of the first and second types (0.7097-0.7140 Sr-87/Sr-86; 17.97-18.29 Pb-206/Pb-204; 38.11-38.45 Pb-208/Pb-204) are distinctly more radiogenic than those of the third type (0.7094-0.7115 Sr-87/Sr-86; 17.86-18.05 Pb-206/Pb-204; 37.95-38.19 Pb-208/Pb-204) which, in turn, are closer to Paleozoic ores and carbonates. Fluid inclusion data indicate that the fluids responsible for mineralization of the first and second types of deposits were hot and dilute (T(h)= 370-degrees-140-degrees-C; <5 wt % NaCl equiv). In contrast, relatively colder and very saline fluids (T(h)= 140-degrees-70-degrees-C; >20 wt % NaCl equiv) were responsible for the third type of mineralization, as well for epigenetic dolomitization of the Cambrian host rocks. O isotopes measured in minerals from the first two types (deltaO-18SMOW = 12.8-18.9 parts per thousand) are O-18 depleted with respect to the third type (deltaO-18SMOW = 15.9-22.1 parts per thousand). These data, coupled with fluid inclusion formation temperatures, indicate that the fluids responsible for the first two types of mineralization were O-18 enriched with respect to those of the third type and related hydrothermal phenomena. The deltaS-34CDT in sulfides of the first two types vary between 3.7 and 10.73 per mil, whereas the values of the third type range from 12.0 to 17.9 per mil. Late to post-Hercynian mineralization is thus explained as the result of three distinct, though partly superimposed, hydrothermal systems. System 1 developed closer to the late Hercynian leucogranitic intrusions and led to the formation of the first and subsequently the second type of mineralization. The relatively hot and diluted fluids had a heated meteoric, or even partly magmatic, origin. Metals were leached from an external, radiogenic source, represented either by Hercynian leucogranites or by Paleozoic metasediments. Sulfur had a partly magmatic signature. System 2 was characterized by very saline, colder fluids which promoted dolomitization, silicification, and vein and karst mineralization. These fluids share the typical characteristics of formation waters, even though their origins remain highly speculative. The hydrothermal system was mainly rock dominated, with only a minor participation of the external radiogenic source of metals. Sulfur was derived by recirculation of pre-Hercynian strata-bound ores. System 3 records the invasion of fresh and cold meteoric waters which precipitated only minor ore and calcite gangue. It may represent the further evolution of system 2, possibly spanning a time well after the Permo-Triassic. The timing of all these phenomena is still questionable, due to the poor geologic record of the Permo-Triassic in southwest Sardinia. Nevertheless, the hypothesized scenario bears many similarities with hydrothermal processes documented throughout the Hercynian in Europe and spanning the same time interval. A comparison with the latter mineralization and hydrothermal activities leads to the hypothesis that the first two types of mineralization are linked to late Hercynian magmatic activity, whereas the third type may be related to either strike-slip or tensional tectonics which, throughout Europe mark the transition from the Hercynian orogeny to the Alpine cycle

The astronomical theory of climate and the age of the Brunhes-Matuyama magnetic reversal, 1994, Bassinot Fc, Labeyrie Ld, Vincent E, Quidelleur X, Shackleton Nj, Lancelot Y,
Below oxygen isotope stage 16, the orbitally derived time-scale developed by Shackleton et al. [1] from ODP site 677 in the equatorial Pacific differs significantly from previous ones [e.g., 2-5], yielding estimated ages for the last Earth magnetic reversals that are 5-7% older than the K/Ar values [6-8] but are in good agreement with recent Ar/Ar dating [9-11]. These results suggest that in the lower Brunhes and upper Matuyama chronozones most deep-sea climatic records retrieved so far apparently missed or misinterpreted several oscillations predicted by the astronomical theory of climate. To test this hypothesis, we studied a high-resolution oxygen isotope record from giant piston core MD900963 (Maldives area, tropical Indian Ocean) in which precession-related oscillations in [delta]18O are particularly well expressed, owing to the superimposition of a local salinity signal on the global ice volume signal [12]. Three additional precession-related cycles are observed in oxygen isotope stages 17 and 18 of core MD900963, compared to the composite curves [4,13], and stage 21 clearly presents three precession oscillations, as predicted by Shackleton et al. [1]. The precession peaks found in the [delta]18O record from core MD900963 are in excellent agreement with climatic oscillations predicted by the astronomical theory of climate. Our [delta]18O record therefore permits the development of an accurate astronomical time-scale. Based on our age model, the Brunhes-Matuyama reversal is dated at 775 10 ka, in good agreement with the age estimate of 780 ka obtained by Shackleton et al. [1] and recent radiochronological Ar/Ar datings on lavas [9-11]. We developed a new low-latitude, Upper Pleistocene [delta]18O reference record by stacking and tuning the [delta]18O records from core MD900963 and site 677 to orbital forcing functions

The exposed carbonates of the Bahamas consist of late Quaternary limestones that were deposited during glacio-eustatic highstands of sea level. Each highstand event produced transgressive-phase, stillstand-phase, and regressive-phase units. Because of slow platform subsidence, Pleistocene carbonates deposited on highstands prior to the last interglacial (oxygen isotope substage 5e, circa 125,000 years ago) are represented solely by eolianites. The Owl's Hole Formation comprises these eolianites, which are generally fossiliferous pelsparites. The deposits of the last interglacial form the Grotto Beach Formation, and contain a complete sequence of subtidal intertidal and eolian carbonates. These deposits are predominantly oolitic. Holocene deposits are represented by the Rice Bay Formation, which consists of intertidal and eolian pelsparites deposited during the transgressive-phase and stillstand-phase of the current sea-level highstand. The three formations are separated from one another by well-developed terra-rossa paleosols or other erosion surfaces that formed predominantly during intervening sea-level lowstands. The karst landforms of San Salvador consist of karren, depressions, caves, and blue holes. Karren are small-scale dissolutional etchings on exposed and soil-covered bedrock that grade downward into the epikarst, the system of tubes and holes that drain the bedrock surface. Depressions are constructional features, such as swales between eolian ridges, but they have been dissolutionally maintained. Pit caves are vertical voids in the vadose zone that link the epikarst to the water table. Flank margin caves are horizontal voids that formed in the distal margin of a past fresh-water lens; whereas banana holes are horizontal voids that developed at the top of a past fresh-water lens, landward of the lens margin. Lake drains are conduits that connect some flooded depressions to the sea. Blue holes are flooded vertical shafts, of polygenetic origin, that may lead into caves systems at depth. The paleokarst of San Salvador is represented by flank margin caves and banana holes formed in a past fresh-water lens elevated by the last interglacial sea-level highstand, and by epikarst buried under paleosols formed during sea-level lowstands. Both carbonate deposition and its subsequent karstification is controlled by glacio-eustatic sea-level position. On San Salvador, the geographic isolation of the island, its small size, and the rapidity of past sea level changes have placed major constraints on the production of the paleokarst

Ancient helictites and the formation of vadose crystal silt in upper Jurassic carbonates (Southern Germany), 1998, Reinhold C. ,
Speleothems and vadose crystal silt are effective indications for karstification processes in the fossil record. Upper Jurassic limestones in Southern Germany that have undergone vadose diagenesis contain on crystal margins and tips of coarse bladed calcites numerous fibrous calcite crystals, formed by abnormal growth conditions, and internal sediment within fractures and vugs, Fibrous calcite crystals grew as crusts, in fence and mesh-like arrangements. Fibrous crystals, which have a length:width ratio of greater than 1:10, are made up of stacked subcrystals composed of an alternation of hexagonal prisms and rhombohedra, They exhibit a central to somewhat eccentric capillary. Electron probe microanalysis shows low-Mg calcite mineralogy with negligible amounts of Fe, Mn, and Sr as well as dis seminated clay and metal hydroxide impurities. Stable-isotope data show relatively C-13-enriched and O-18-depleted values (delta(13)C similar to parts per thousand PDB, delta(18)O similar to -6 parts per thousand PDB), suggesting a meteoric environment and CO2 degassing as the main process of formation, Fibrous calcite crystals form from capillary fluids that are highly supersaturated with respect to calcium carbonate, contaminated with alien mineral impurities. The abnormal growth pattern is suggested to be substrate-controlled and attributed to mineral impurities that produce numerous crystallization nuclei. Fibrous calcite crystals are comparable to helictites of the filiform type that are reported only from Quaternary caves. Nevertheless, the diagenetic sequence and oxygen isotope data suggest a Late Cretaceous to early Tertiary age for their formation. The internal sediment consists exclusively of silt-size fragments of fibrous crystals and therefore is comparable to vadose crystal silt. Crystal silt is generated by the erosion of fibrous crystals both by va dose seepage and air currents. This study is the first observation of ancient helictites and related vadose crystal silt, documenting the close relationship between pore ceiling vadose cements and the generation of crystal silt

Isotopic Stratigraphy of a Last Interglacial Stalagmite from Northwestern Romania: Correlation with the Deep-sea Record and Northern-latitude Speleothem, 1999, Lauritzen, S. E. , Onac, B. P.
LFG-2, a 39.5 cm tall stalagmite from northwestern Romania, has been dated by U-series a-spectrometric dating, and analyzed for stable isotope variations (d18O, d13C) along its growth axis. The sample grew all the way through oxygen isotope stage 5(a-e), and perhaps for some time into stage 4. In spite of a rather low uranium content and therefore imprecise chronology, the sample provides an interesting stable isotope record with high temporal resolution that correlates favorably with other speleothems and with the deep-sea record. Termination II is well defined in the record as a rapid shift from light (cold) to heavier (warm) d18O values, when C3 vegetation seemed to dominate. The d13C in a slow growth zone, corresponding to oxygen isotope stage 5d, as well after the stage 5/4 transition, suggests that C4 plants possibly dominated the surface environment. The d18O record also correlate quite well with the a-dated FM-2 record from northern Norway

Continental oxygen isotope record of the last 170,000 years in Jerusalem., 1999, Frumkin A. , Ford D. C. , Schwarcz H. P.

Speleothem evidence for Holocene fluctuations of the prairie-forest ecotone, north-central USA, 1999, Denniston Rf, Gonzalez La, Baker Rg, Asmerom Y, Reagan Mk, Edwards Rl, Alexander Ec,
Carbon and oxygen isotopic trends from seven Midwestern speleothems record significant offsets in the timing of middle-Holocene vegetation change. Interactions of dry Pacific and moist Gulf of Mexico air masses maintained a sharp moisture gradient across Iowa, Minnesota, and Wisconsin such that the arrival of prairie was offset by 2000 years between caves and pollen sites located only 50 km apart. Oxygen isotopes shift concomitantly with carbon in most cases, although these changes are believed to represent increased evaporative enrichment of 18O prior to infiltration during the prairie period

A review of the last interglacial sea-level highstand (oxygen isotope substage 5e): Duration, magnitude and variability from Bahamian Data, 1999, Carew J. L. , Mylroie J. E.

Karst processes on Cayman Brac, a small oceanic carbonate island, PhD Thesis, 1999, Tarhulelips, Rozemarijn Frederike Antoinette

Cayman Brac is a good example of a small oceanic carbonate island which has undergone several periods of submergence and emergence since the Tertiary, resulting in the geological formations being well karstified. This study investigated several karst phenomena on the island including the occurrence and morphology of caves, the water chemistry and microclimate inside the caves, periods of speleothem growth and dissolution, and bell holes. Caves occur throughout the island at various elevations above sea level. Using elevation as a criterion, the caves were divided into Notch caves, located at, or one-two metres above, the Sangamon Notch, and Upper caves, located at varying elevations above the Notch. Analysis of the morphology, age and the relative abundance of speleothem in the caves further supports this division. The close proximity of the Notch and the Notch caves is coincidental: speleothem dating by U-series methods shows that the caves predate the Notch. They are believed to have formed between 1400 and 400 ka, whereas a late Tertiary to Early Quaternary age is assigned to the Upper caves. Speleothem on the island has suffered minor, moderate and major dissolution. Minor dissolution is due to a change in the degree of saturation of the drip water feeding the speleothem, whereas the last two are caused by flooding or condensation corrosion. Many of the speleothems in fact experienced several episodes of dissolution followed by regrowth. The latest episode appears to be caused by condensation corrosion rather than flooding. Eleven speleothems containing growth hiatuses were dated by U-series methods. The results indicate that growth cessation did not occur synchronously. Furthermore, the timing of the hiatuses during the Quaternary is not restricted to glacial or interglacial periods. Oxygen and carbon stable isotope analyses of seven of the samples reveal an apparent shift towards a drier and warmer climate around 120 ka. However, more data and further collaborative evidence is desirable. Of six samples with hiatuses, five show a bi-modal distribution of stable isotope values: before and after the hiatus. Oxygen isotope analyses of modern drip water found inter-sample variations of over 2[per thousand]. This is due to cave environmental factors such as evaporation, infiltration velocity and roof thickness. Inside the caves δ 18 O of drip water decreases with increasing distance from the entrance and thus decreasing external climatic influence. This distance-climatic effect is also reflected in the δ18 O calculated for modern calcite: -5.3, -6.5 and -7.6[per thousand] VPDB at 3, 10 and 20 m respectively. The morphology of bell holes, found only in certain Notch caves, was studied in detail. It is proposed that the bell holes are formed by condensation corrosion, probably enhanced by microbiological activity. The study represents a comprehensive and thorough analyses of karst features on a small oceanic island, and provides information useful for climatic reconstruction during the Quaternary

Isotopic, geochemical and biological tracing of the source of an impacted karst spring, Weldon Spring, Missouri, 2001, Criss Re, Fernandes Sa, Winston We,
Weldon Spring is consistently enriched in O-18 relative to other karst springs in east-central Missouri and western Illinois, suggesting an evaporated source component. Regional potentiometric head maps of the shallow aquifer suggest that Prairie Lake, an artificial lake built between 1954 and 1982, could represent this component. Isotopic, biological and chemical tracing of the spring conclusively verify the hypothesis that this lake has impacted Weldon Spring. Mixing calculations indicate that Weldon Spring is now comprised of approximately 80% lake water and 20% groundwater. Recent measurements indicate that the discharge rate of the spring is now approximately 10 times the rate prior to the construction of the lake, confirming the augmentation of flow by a new source. Analysis of the isotopic trends indicates that the subsurface travel time is short, and suggests that the conduits connecting the lake and the spring may be progressively enlarging. (C) 2001 AEHS

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