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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 anisotropic steering is anisotropic structures (anisotropies) in the rock like schistosity, inclusions and fractures which can deviate or 'steer' the direction of fractures subsequently developed.?

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 ratios (Keyword) returned 116 results for the whole karstbase:
Showing 1 to 15 of 116
Origin of the sedimentary deposits of the Naracoorte Caves, South Australia, , Forbes Ms, Bestland Ea,
The origin of the sediments located in the Naracoorte Caves (South Australia) was investigated via the analysis of strontium isotope ratios (87Sr/86Sr), elemental geochemistry, and mineralogy. Sedimentary deposits located in Robertson, Wet, Blanche and several other chambers in Victoria Cave are all variable mixes of fine sand and coarse silts, which display similar and consistent strontium isotope ratios (0.717-0.725). This suggests that over the 400[no-break space]ka time frame that these deposits span there has been minimal variation in the source of the clastic sediments. Increased strontium concentrations for these cave sediments correspond with increasing silt content, yet there is no correlation between 87Sr/86Sr ratios and silt content. This implies that the silt-sized component of the sediments is the main contributor of strontium to the cave sediments. Comparisons of 87Sr/86Sr with regional surficial deposits show a significant correlation between the cave sediments (avg: 0.7228; n = 27), the fine silt lunettes of the Bool Lagoon area (avg: 0.7224; n = 4), the sandy A horizons of the Coonawarra Red Brown Earths (RBEs; avg: 0.726; n = 5), and Holocene age podsolic sand deposits (0.723). These data suggest that there has been substantial flux from this group of deposits to the caves, as would be expected considering prevailing winds. This relationship is further supported by a strong correlation between many trace elements, including Ti, Zr, Ce, and Y; however, variations in clay mineralogy suggest that the fine silt-dominated lunettes and Padthaway RBEs were not significant contributors to the cave deposits. Hence, the detritus entering the caves was more than likely from areas proximal to the cave entrance and was dominated by medium grain-sized materials. Major regional deposits, including the coarser-grained, calcite-rich Bridgewater Formation sands, basalts from the lower SE, Padthaway Horst granites, Gambier limestone, and metamorphics from the Adelaide geosyncline show minimal correlation in 87Sr/86Sr ratios, elemental geochemistry, and mineralogy with the cave sediments, and are discounted as significant sources. In comparison, 87Sr/86Sr ratios for the Coorong silty sands (0.717-0.724), Lower Murray sands (0.727-0.730), and the medium size silt component of the Murray-Darling River system (0.71-0.72), compare favourably with the cave sediments. This relationship is further supported by similarities in elemental chemistry and mineralogy. Thus, much of the strontium-rich silt that is now located in the Naracoorte Cave sediments likely originated from the Murray-Darling basin. Over time, this material has been transported to the SE of South Australia, where it mixed with the medium sand component of the regressive dune ridge sequence, locally derived organic matter, limestone fragments, and fossil material to produce the unique deposits that we see evident in many of the chambers of the Naracoorte Cave system today

Sex Ratios in Hibernating Bats, 1950, Hitchcock, Harold B.

The use of Saturation Index and Potassium/Sodium ratios as indicators of Speleological potential with special reference to Derbyshire, 1975, Christopher N. S. J.

A study of fresh water lens configuration in the Cayman Islands using resistivity methods, 1976, Bugg Sf, Lloyd Jw,
The problems of identifying the base of fresh water lenses in oceanic islands are discussed. A study carried out in the Cayman Islands is described in which the lens base is defined in relation to potable water standards and mapped using surface resistivity measurements with salinity profile controls in boreholes. Using depth-salinity ratios the piezometric surface is then determined. The technique is considered to provide a reliable cheap and rapid method of obtaining lens geometry in oceanic islands particularly where fairly homogeneous lithologies are present

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

Some practical considerations in the use of K/Na ratios in spelaeological reconnaissance, 1978, Manley D. B. , Taylor G. S.

Variation among Populations of the Troglobitic Amphipod Crustacean Crangonyx antennatus Packard (Crangonyctidae) Living in Different Habitats, III: Population Dynamics and Stability., 1981, Dickson Gary W. , Holsinger John R.
Populations of the troglobitic amphipod Crangonyx antennatus from caves in Lee Co., Virginia (U.S.A.) were investigated on both a short and long term basis. The dynamics of populations living in two distinct aquatic cave habitats (mud-bottom pools and gravel-bottom streams) were compared seasonably for one year. Sex ratios indicated a larger number of females in both pool and stream habitats. The majority of males in both habitats were found to be sexually mature throughout the year investigated. Seasonal fluctuations in female maturity were observed in both habitats, with larger numbers collected in June and August. In addition, a larger number of ovigerous females were observed in the spring, indicating the possibility of a circannian reproductive cycle in both pools and streams. The structure of populations from the caves studied appears to reflect a controlled recruitment of females from immature to mature stages. In order to determine the stability of population structure, collection data from a pool and a stream habitat for a l0-year period were analyzed. Population structures were found to be relatively stable over long periods in both habitats, with immature females comprising the dominant population class.

Lithification of peritidal carbonates by continental brines at Fisherman Bay, South Australia, to form a megapolygon/spelean limestone association, 1982, Ferguson J, Burne Rv, Chambers La,
Lithification, which commenced less than 3000 yrs BP is still active, and has formed a cavernous limestone containing megapolygons, tepees, and speleothems including pisoliths, floe aragonite, and aragonite pool deposits. The emerging waters evolved from low alkalinity waters of Pleistocene sand and clay coastal plain aquifers which passed through an underlying Tertiare marine carbonate aquifer, have high P CO2 , total carbonate, Ca, and sulfate concentrations. They are close to saturation with respect to aragonite, and their mMg (super 2) /mCa (super 2) ratios approach or exceed the critical aragonite precipitation value. Features which diagnose ancient examples of this process: primary aragonitic cements with high mSr (super 2) /mCa (super 2) values; nonmarine delta 34 S values in gypsum; two superimposed networks of surface polygons, one delineated by extensional boundaries, the other by tepees; high-water vadose-zone isopachous grain cements; interconnected, speleothem-lined cavities; and the presence of evaporites only in surface sediments. Possible ancient examples are recognized in West Texas, Lombardy, and the Atlas Mountains. The areal extent of each of these deposits suggests that the process may be a geologically important feature, and its products may be diagnostic of semi-arid or arid-zone paralic sedimentation.--Modified journal abstract

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.

Strontium geochemical evidence for the origin of the barite deposits from Sardinia, Italy, 1984, Barbieri M, Masi U, Tolomeo L,
Sr content of 137 samples of barite, 81 samples of fluorite, and 65 samples of calcite from 27 post-Cambrian karst and hydrothermal deposits. Karst calcites have an average Sr content of 26 ppm, quite similar to that of the hydrothermal calcites. Hydrothermal fluorites show an average content of 56 ppm. Forty-five percent of the karst barites have an Sr content over 6,000 ppm, while as much as 83.8 percent of the hydrothermal barites contain more than 6,000 ppm Sr. The Sr isotope composition of the Cambrian stratiform barites (0.70867 or - 3) is similar to that of Cambrian seawater, suggesting that the bulk of the Sr was provided by this source. The Sr isotope ratios of the karst barite (average 87 Sr/ 86 Sr = 0.70947 or - 1) indicate that Sr was not only derived by recycling of the stratiform barite but was also provided by the noncarbonate fraction of the Cambrian wall rocks. The Sr isotope composition of the hydrothermal barites ranges from 0.70990 or - 4 to 0.71837 or - 4, suggesting that the Sr derived mainly from a high 87 Sr/ 86 Sr ratio source.--Modified journal abstract

Groundwater chemistry and cation budgets of tropical karst outcrops, Peninsular Malaysia, I. Calcium and magnesium, 1989, Crowther J,
The discharge and chemical properties of 217 autogenic groundwaters were monitored over a 1-yr period in the tower karsts of central Selangor and the Kinta Valley, and in the Setul Boundary Range. Because of differences in soil PCO2, calcium concentrations are significantly higher in the Boundary Range (mean, 82.5 mg l-1) than in the tower karst terrain (44.6 mg l-1). Local differences in both source area PCO2 and amounts of secondary deposition underground cause marked intersite variability, particularly in the tower karst. Dilution occurs during flood peaks in certain conduit and cave stream waters. Generally, however, calcium correlates positively with discharge, since the amount of secondary deposition per unit volume of water decreases at higher flows. Magnesium concentrations and Mg:Ca Mg ratios of groundwaters are strongly influenced by bedrock composition, though bedrock heterogeneity and the kinetics and equilibria of carbonate dissolution reactions preclude extremely low or high Mg:Ca Mg values. Net chemical denudation rates range from 56.6 to 70.9 m3km2yr-1.The results are considered in relation to cation fluxes in surface runoff, soil throughflow and nutrient cycling. Preliminary calcium and magnesium budgets show that (1) dissolutional activity is largely confined to the near-surface zone; and (2) the annual uptake of calcium and magnesium by tropical limestone forests is similar in magnitude to the net solute output in groundwaters

The stable isotopic ratios of drip water, pool water and water vapor collected in remote areas of Carlsbad Cavern, New Mexico, were used to develop a conceptual model of the hydrologic conditions of the cave pools. When considered in terms of open and closed pool systems, the data indicate that the pools in Carlsbad Cavern appear to leak more water than they evaporate. The pools in Carlsbad Cavern range between -43 and -31% in delta-D, -7.4 and -5.9% in delta-O-18, and have EC-values of 365-710 mu-S cm(-1). The water vapor is consistently 80-82% more depleted in D than associated pool water and appears to be under direct isotopic control by the pools. Most of the drip water ranges between -51 and -44% in delta-D, between -8.0 and -6.9% in delta-O-18, and have EC-values of 310-350 mu-S cm(-1), regardless of location of collection in the cave. Drip water collected on popcorn formations (which in this case are formed by evaporation of wall seep) have stable isotopic compositions similar to local pool water; however, they have EC-value of up to 1060 mu-S cm(-1). In addition, a small, closed pool near the Lake of the Clouds has stable isotopic compositions similar to those of the Lake and elevated EC-values of up to 9500 mu-S cm(-1). The degree of stable isotopic enrichment that evaporating waters can obtain in the Cavern is limited by exchange with the water vapor which, in turn, appears to be controlled by the pools

Formation of 13C/12C isotope ratios in speleothems: a semi-dynamic model, 1990, Dulinski M. , Rosanski K.

The lead-zinc ore deposits of the Siding-Gudan mineral subdistrict Guangxi are part of the large Nanling district of South China, and hosted in Devonian carbonate rocks. The ore bodies occur significantly along main faults and fault zones, and concentrate up to 300 meters above the Cambrian/Devonian unconformity. Connected with hydrothermal karst, size and volume of the ore bodies increase in proximity to this unconformity. Moving from the unaffected host rocks to the center of the ore bodies, four zones can be discriminated by the mineral assemblage (pyrite, sphalerite, galena) as well as by the degree of ordering, Ca/Mg, and Fe/Mn ratios of different dolomites. Homogenization temperatures range from 80-100-degrees-C (Presqu'ile dolomite) to 230-260-degrees-C (massive sphalerite). The sulfides reveal delta-S-34 = -20 to parts per thousand, and fluid inclusions display a salinity of 5-12 wt % equivalent NaCl. The diagenetic and hydrothermal history is similar to that of classic Mississippi Valley Type (MVT) sulfide mineral deposits as, for example, Pine Point in Canada. Mineralization and remobilization of the sulfides took place during a wide time span from late Paleozoic through Mesozoic. Both processes are considered as an interaction of saline basinal brines ascended from the adjoining dewatering trough, and magmatic-hydrothermal fluids of several magmatic-tectonic events

Distribution of the rare earth elements (REE, including La-Lu, Y) along vertical profiles is presented for four well-studied karst-bauxite deposits from Yugoslavia and Greece. For one deposit from Jamaica, La and Y contents are given. All deposits display a downward enrichment of the REE culminating at the base, where authigenic REE minerals have been formed. This REE pattern is characteristic for karst-bauxites formed in situ through the bauxitization of argillaceous material collected in karstic depressions. In this way, the highest enrichment of the REE in the sedimentary cycle has been achieved. Both light REE (LREE) and heavy REE (HREE) were 'mobile' during the bauxitization process and were concentrated at the alkaline barrier of the carbonate footwall. In four out of five studied deposits, the ratios SIGMA-LREE/SIGMA-HREE and La/Y in bauxites decrease downwards, showing an enrichment of the HREE relative to LREE. A further fractionation of the REE took place in the formation of authigenic REE minerals, which exhibit a very high enrichment of LREE relative to HREE. In spite of this, these minerals and bauxites in four studied deposits have a general similarity of the REE distribution patterns, which indicate a close genetic relationship

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