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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 blind valley is 1. a karst valley abruptly terminated by the passage underground of the watercourse which has hitherto resisted the karst processes and remained at the surface. an intermediate type, the half-blind valley, exists in which the valley form continues downstream from the sinkhole used under conditions of normal river flow. the watercourse only flows here intermittently and the valley may (except for its use as a flood conduit) be fossil in that it represents the section abandoned by the river as it sought progressively higher swallow holes [19]. 2. a karst valley with no evident downstream continuation, and one in which the water drains and disappears underground into one or more ponors [20]. 3. a valley that terminates abruptly at a point where its stream sinks, or once sank, underground. as sinks develop higher up the blind valley, the original valley termination may be dry under most flow conditions [9]. related to marginal polje. synonyms: (french.) vallee aveugle; (german.) blindtal, (kesseltal); (greek.) kliste karstike kilas; (italian.) valle cieca, valle chiusa; (russian.) slepaja dolina; (spanish.) valle ciego; (turkish.) kor vadi; (yugoslavian.) slijepa dolina, sepa dolina. see also half-blind valley; marginal polje.?

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Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
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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 delta-o-18 (Keyword) returned 10 results for the whole karstbase:
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

Petrography of the Lower Ordovician Ellenburger Group, both in deeply-buried subsurface cores and in outcrops which have never been deeply buried, documents five generations of dolomite, three generations of microquartz chert, and one generation of megaquartz. Regional periods of karstification serve to subdivide the dolomite into 'early-stage', which predates pre-Middle Ordovician karstification, and 'late-stage', which postdates pre-Middle Ordovician karstification and predates pre-Permian karstification. Approximately 10% of the dolomite in the Ellenburger Group is 'late-stage'. The earliest generation of late-stage dolomite, Dolomite-L1, is interpreted as a precursor to regional Dolomite-L2. L1 has been replaced by L2 and has similar trace element, O, C, and Sr isotopic signatures, and similar cathodoluminescence and backscattered electron images. It is possible to differentiate L1 from L2 only where cross-cutting relationships with chert are observed. Replacement Dolomite-L2 is associated with the grainstone, subarkose, and mixed carbonate-siliciclastic facies, and with karst breccias. The distribution of L2 is related to porosity and permeability which focused the flow of reactive fluids within the Ellenburger. Fluid inclusion data from megaquartz, interpreted to be cogenetic with Dolomite-L2, yield a mean temperature of homogenization of 85 6-degrees-C. On the basis of temperature/delta-O-18-water plots, temperatures of dolomitization ranged from approximately 60 to 110-degrees-C. Given estimates of maximum burial of the Ellenburger Group, these temperatures cannot be due to burial alone and are interpreted to be the result of migration of hot fluids into the area. A contour map of delta-O-18 from replacement Dolomite-L2 suggests a regional trend consistent with derivation of fluids from the Ouachita Orogenic Belt. The timing and direction of fluid migration associated with the Ouachita Orogeny are consistent with the timing and distribution of late-stage dolomite. Post-dating Dolomite-L2 are two generations of dolomite cement (C1 and C2) that are most abundant in karst breccias and are also associated with fractures, subarkoses and grainstones. Sr-87/Sr-86 data from L2, C1, and C2 suggest rock-buffering relative to Sr within Dolomite-L2 (and a retention of a Lower Ordovician seawater signature), while cements C1 and C2 became increasingly radiogenic. It is hypothesized that reactive fluids were Pennsylvanian pore fluids derived from basinal siliciclastics. The precipitating fluid evolved relative to Sr-87/Sr-86 from an initial Pennsylvanian seawater signature to radiogenic values; this evolution is due to increasing temperature and a concomitant evolution in pore-water geochemistry in the dominantly siliciclastic Pennsylvanian section. A possible source of Mg for late-stage dolomite is interpreted to be from the dissolution of early-stage dolomite by reactive basinal fluids

The hydrology of a small karst drainage basin in Jamaica, the Martha Brae River basin, was examined using stable isotopes. Variations in the isotopic composition of the groundwaters sampled and their positions relative to the local meteoric water line on a delta-D/delta-O-18 diagram permitted the identification of two distinct groundwater types. The isotopic data also provided evidence that the most productive portion of the aquifer is divided by a major fault, which impedes groundwater flow. Information regarding the mechanisms and elevation of recharge was inferred from the delta-D versus delta-O-18 relationships and differences in isotopic composition, respectively

Changes in the isotopic and chemical composition of ground water resulting from a recharge pulse from a sinking stream, 1998, Katz B. G. , Catches J. S. , Bullen T. D. , Michel R. L. ,
The Little River, an ephemeral stream that drains a watershed of approximately ss km(2) in northern Florida, disappears into a series of sinkholes along the Cody Scarp and flows directly into the carbonate Upper Floridan aquifer, the source of water supply in northern Florida. The changes in the geochemistry of ground water caused by a major recharge pulse from the sinking stream were investigated using chemical and isotopic tracers and mass-balance modeling techniques, Nine monitoring wells were installed open to the uppermost part of the aquifer in areas near the sinks where numerous subterranean karst solution features were identified using ground penetrating radar. During high-flow conditions in the Little River, the chemistry of water in some of the monitoring wells changed, reflecting the mixing of river water with ground water. Rapid recharge of river water into some parts of the aquifer during high-flow conditions was indicated by enriched values of delta O-18 and delta deuterium (-1.67 to -3.17 per mil and -9.2 to -15.6 per mil, respectively), elevated concentrations of tannic acid, higher (more radiogenic) Sr-87/Sr-86 ratios, and lower concentrations of Rn-222, silica, and alkalinity compared to low-how conditions. The proportion of river water that mixed with ground water ranged from 0.10 to 0.67 based on binary mixing models using the tracers O-18, deuterium, tannic acid, silica, Rn-222, and Sr-87/Sr-86. On the basis of mass-balance modeling during steady-state how conditions, the dominant processes controlling carbon cycling in ground water are the dissolution of calcite and dolomite in aquifer material, and aerobic degradation of organic matter. (C) 1998 Elsevier Science B.V. All rights reserved

Determination of the sources of nitrate contamination in karst springs using isotopic and chemical indicators, 2001, Panno S. V. , Hackley K. C. , Hwang H. H. , Kelly W. R. ,
The sources of nitrate (NO3-) in groundwater of the shallow karst aquifer in southwestern Illinois' sinkhole plain were investigated using chemical and isotopic techniques. The groundwater in this aquifer is an important source of potable water for about half of the residents of the sinkhole plain area. Previous work has shown that groundwater from approximately 18% of the wells in the sinkhole plain has NO3- concentrations in excess of the USEPA's drinking water standard of 10 mg N/1 Relative to background levels, the NO3- concentrations in water from 52% of the wells, and probably all of the springs in the study area, are anomalously high, suggesting that sources other than naturally occurring soil organic matter have contributed additional NO3- to groundwater in the shallow karst aquifer. This information, and the dominance of agriculture in the study area, suggest that agrichemical contributions may be significant. To test this hypothesis, water samples from 10 relatively large karst springs were collected during four different seasons and analyzed for inorganic constituents, dissolved organic carbon, atrazine, and delta (15) N and delta O-18 of the NO3- ions. The isotopic data were most definitive and suggested that the sources of NO3- in spring water are dominated by N-fertilizer with some possible influence of atmospheric NO3- and, to a much lesser extent, human and/or animal waste. Differences in the isotopic composition of NO3- and some of the chemical characteristics were observed during the four consecutive seasons in which spring water samples were collected. Isotopic values for delta N-15 and delta O-18 of the NO3- ranged from 3.2%o to 19.1%o and from 7.2%o to 18.7%o respectively. The trend of delta N-15 and delta O-18 data for NO3- also indicated that a significant degree of denitrification is occurring in the shallow karst hydrologic system (within the soil zone, the epikarst and the shallow karst aquifer) prior to discharging to springs. (C) 2001 Elsevier Science B.V. All rights reserved

Differences in the C-14 age, delta C-13 and delta O-18 of Holocene tufa and speleothem in the Dinaric Karst, 2003, Horvatincic N. , Bronic I. K. , Obelic B. ,
We studied Holocene speleothems and tufa samples collected in numerous caves and rivers in the Dinaric Karst of Croatia, Slovenia, Bosnia and Herzegovina, as well as Serbia and Montenegro. Differences in the formation process of tufa and speleothems are discussed in the context of their isotopic composition (C-14, C-13 and O-18), as well as the chemistry of surface water (rivers, lakes) and drip water (in caves). The physical and chemical parameters monitored in the surface water (tufa precipitation) and drip water (speleothem precipitation) show that more stable conditions accompany speleothem rather than tufa formation. This is particularly obvious in the water temperature variations (2-22degreesC in surface water and 7-12degreesC in drip water) and in saturation index variation (3-11 in surface water and 1-6 in drip water). The range of C-14 ages recorded by Holocene speleothems (similar to 12 000 yr) is wider by several thousands years than that of Holocene tufa samples (similar to 6000 yr). delta(13)C values for tufa samples range from -12parts per thousand to -6parts per thousand and for speleothem samples from -12parts per thousand to ?? per thousand reflecting higher soil carbon and/or vegetation impact on the process of tufa than on speleothem formation. The differences in delta(18)O values of tufa and speleothem samples from different areas reflect different temperature conditions and differing isotopic composition in the water. The study shows that speleothems from the Dinaric Karst can be used as global palaeoclimatic records, whereas tufa records changes in the local palaeoenvironment. (C) 2003 Elsevier Science B.V. All rights reserved

Use of stable isotopes to quantify flows between the Everglades and urban areas in Miami-Dade County Florida, 2004, Wilcox W. M. , Sologabriele H. M. , Sternberg L. O. R. ,
An isotopic study was performed to assess the movement of groundwater for a site located in Miami-Dade County, Florida. The site encompasses portions of a protected wetland environment (northeast Everglades National Park) and suburban residential Miami, incorporating municipal pumping wells and lakes formed by rock mining. Samples of ground, surface, and rainwater were analyzed for their isotopic composition (oxygen-18 and deuterium). Various analytical and graphical techniques were used to analyze this data and two conceptual box models were developed to quantify flows between different regions within the site. Results from this study indicate that the aquifer underlying the study site (the Biscayne aquifer) is highly transmissive with the exception of two semi-confining layers of reduced hydraulic conductivity. Everglades surface water infiltrates into the aquifer and migrates east toward residential areas. In these urban areas, 'shallow' groundwater (above the deeper semi-confining layer) is substantially affected by urban rainfall while 'deep' groundwater (below the deeper semi-confining layer) maintains a composition similar to that of Everglades water. Rock mining lakes in the area provide 'breaks' in the semi-confining layers that allow for mixing of shallow and deep groundwater. As water travels eastward, municipal well intakes, screened to a depth below the deeper semi-confining layer, draw upon not only shallow urban water (predominantly comprised of urban rainfall) and lake water (having influences from both urban rainfall and Everglades water) but also deep water that originated in the Everglades. Results from one of the box models estimate that over 60% of the water being removed by municipal pumping originated in the Everglades. These conclusions suggest that Everglades water, both directly through deep groundwater flow and indirectly through mixing with rock-mining lakes, is being drawn into the operating municipal wellfield.

Stable isotope study of cave percolation waters in subtropical Brazil: Implications for paleoclimate inferences from speleothems, 2005, Cruz Fw, Karmann I, Viana O, Burns Sj, Ferrari Ja, Vuille M, Sial An, Moreira Mz,
We analyze the interannual monthly variability of oxygen isotope ratios in data from IAEA stations along the Atlantic coast of South America between 23 degrees and 34 degrees S to evaluate the influence of parameters such as temperature, rainfall amount and moisture source contribution on meteoric water recharging two karst systems in subtropical Brazil. In addition, a 2 year monitoring program performed on soil and cave drip and rimstone pool waters from sampling sites with contrasting discharge values and located at 100 and 300 m below the surface in the Santana Cave System (24 degrees 31' S; 48 degrees 43' W), is used to test the influence of hydrologic and geologic features on the temporal variations of seepage water delta(18)O. Interannual monthly variations in delta(18)O of rainfall reflect primarily regional changes in moisture source contribution related to seasonal shifts in atmospheric circulation from a more monsoonal regime in summer (negative values of delta(18)O) to a more extratropical regime in winter (positive values of delta(18)O). Variations in groundwater delta(18)O indicate that the climatic signal of recent rainfall events is rapidly transmitted through the relatively deep karst aquifer to the cave drip waters, regardless of location of collection in the cave. In addition, the data also suggest that water replenishment in the system is triggered by the increase in hydraulic head during periods when recharge exceeds the storage capacity of the soil and epikarst reservoirs. Significant perturbations in the groundwater composition, characterized by more positive values of delta(18)O, are probably connected to an increased Atlantic moisture contribution associated with extratropical precipitation. This implies that the delta(18)O of speleothems from caves in this region may be a suitable proxy for studying tropical-extratropical interactions over South America, a feature that is intrinsically related to the global atmospheric circulation. (c) 2005 Elsevier B.V. All rights reserved

Modification and preservation of environmental signals in speleothems, 2006, Fairchild Ij, Smith Cl, Baker A, Fuller L, Spotl C, Mattey D, Mcdermott F, Eimp,
Speleothems are primarily studied in order to generate archives of climatic change and results have led to significant advances in identifying and dating major shifts in the climate system. However, the climatological meaning of many speleothem records cannot be interpreted unequivocally, this is particularly so for more subtle shifts and shorter time periods, but the use of multiple proxies and improving understanding of formation mechanisms offers a clear way forward. An explicit description of speleothem records as time series draws attention to the nature and importance of the signal filtering processes by which the weather, the seasons, and longer-term climatic and other environmental fluctuations become encoded in speleothems. We distinguish five sources of variation that influence speleothem geochemistry, i.e. atmospheric, vegetation/soil, karstic aquifer, primary speleothem crystal growth and secondary alteration, and give specific examples of their influence. The direct role of climate diminishes progressively through these five factors. We identify and review a number of processes identified in recent and current work that bear significantly on the conventional interpretation of speleothem records, for example: (1) speleothem geochemistry can vary seasonally and hence a research need is to establish the proportion of growth attributable to different seasons and whether this varies over time; (2) whereas there has traditionally been a focus on monthly mean delta O-18 data of atmospheric moisture, current work emphasizes the importance of understanding the synoptic processes that lead to characteristic isotope signals, since changing relative abundance of different weather types might control their variation on the longer-term; (3) the ecosystem and soil zone overlying the cave fundamentally imprint the carbon and trace element signals and can show characteristic variations with time; (4) new modelling on aquifer plumbing allows quantification of the effects of aquifer mixing; (5) recent work has emphasized the importance and seasonal variability Of CO2-degassing leading to calcite precipitation upflow of a depositional site on carbon isotope and trace element composition of speleothems; (6) although much is known about the chemical partitioning between water and stalagmites, variability in relation to crystal growth mechanisms and kinetics is a research frontier; (7) aragonite is susceptible to conversion to calcite with major loss of chemical information, but the controls on the rate of this process are obscure. Analytical factors are critical in generating high-resolution speleothem records. A variety of methods of trace element analysis is available, but standardization is a common problem with the most rapid methods. New stable isotope data on Irish stalagmite CC3 compares rapid laser-ablation techniques with the conventional analysis of micromilled powders and ion microprobe methods. A high degree of comparability between techniques for delta O-18 is found on the millimeter to centimeter scale, but a previously described high-amplitude oxygen isotope excursion around 8.3 ka is identified as an analytical artefact related to fractionation of the laser-analysis associated with sample cracking. High-frequency variability of not less than 0.5 parts per thousand may be an inherent feature of speleothem delta O-18 records. (c) 2005 Elsevier B.V. All rights reserved

Dolomite formation in breccias at the Musandam Platform border, Northern Oman Mountains, United Arab Emirates, 2006, Breesch L, Swennen R, Vincent B,
The presence of dolomite breccia patches along Wadi Batha Mahani suggests large-scale fluid flow causing dolomite formation. The controls on dolomitization have been studied, using petrography and geochemistry. Dolomitization was mainly controlled by brecciation and the nearby Hagab thrust. Breccias formed as subaerial scree deposits, with clay infill from dissolved platform limestones, during Early Cretaceous emergence. Cathodoluminescence of the dolostones indicates dolomitization took place in two phases. First, fine-crystalline planar-s dolomite replaced the breccias. Later, these dolomites were recrystallized by larger nonplanar dolomites. The stable isotope trend towards depleted values (delta O-18: -2.7 parts per thousand to - 10.2 parts per thousand VPDB and delta C-13: -0.6 parts per thousand to -8.9 parts per thousand VPDB), caused by mixing dolomite types during sampling, indicates type 2 dolomites were formed by hot fluids. Microthermometry of quartz cements and karst veins, post-dating dolomites, also yielded high temperatures. Hot formation waters which ascended along the Hagab thrust are invoked to explain type 2 dolomitization, silicification and hydrothermal karstification. (C) 2006 Elsevier B.V, All rights reserved

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