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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. ...

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That infiltrability is the ease of infiltration [16].?

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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 mass-balance (Keyword) returned 23 results for the whole karstbase:
Showing 16 to 23 of 23
Concepts and models of dolomitization: a critical reappraisal, 2004, Machel Hans G. ,
Despite intensive research over more than 200 years, the origin of dolomite, the mineral and the rock, remains subject to considerable controversy. This is partly because some of the chemical and/or hydrological conditions of dolomite formation are poorly understood, and because petrographic and geochemical data commonly permit more than one genetic interpretation. This paper is a summary and critical appraisal of the state of the art in dolomite research, highlighting its major advances and controversies, especially over the last 20-25 years. The thermodynamic conditions of dolomite formation have been known quite well since the 1970s, and the latest experimental studies essentially confirm earlier results. The kinetics of dolomite formation are still relatively poorly understood, however. The role of sulphate as an inhibitor to dolomite formation has been overrated. Sulphate appears to be an inhibitor only in relatively low-sulphate aqueous solutions, and probably only indirectly. In sulphate-rich solutions it may actually promote dolomite formation. Mass-balance calculations show that large water/rock ratios are required for extensive dolomitization and the formation of massive dolostones. This constraint necessitates advection, which is why all models for the genesis of massive dolostones are essentially hydrological models. The exceptions are environments where carbonate muds or limestones can be dolomitized via diffusion of magnesium from seawater rather than by advection. Replacement of shallow-water limestones, the most common form of dolomitization, results in a series of distinctive textures that form in a sequential manner with progressive degrees of dolomitization, i.e. matrix-selective replacement, overdolomitization, formation of vugs and moulds, emplacement of up to 20 vol% calcium sulphate in the case of seawater dolomitization, formation of two dolomite populations, and -- in the case of advanced burial -- formation of saddle dolomite. In addition, dolomite dissolution, including karstification, is to be expected in cases of influx of formation waters that are dilute, acidic, or both. Many dolostones, especially at greater depths, have higher porosities than limestones, and this may be the result of several processes, i.e. mole-per-mole replacement, dissolution of unreplaced calcite as part of the dolomitization process, dissolution of dolomite due to acidification of the pore waters, fluid mixing (mischungskorrosion), and thermochemical sulphate reduction. There also are several processes that destroy porosity, most commonly dolomite and calcium sulphate cementation. These processes vary in importance from place to place. For this reason, generalizations about the porosity and permeability development of dolostones are difficult, and these parameters have to be investigated on a case-by-case basis. A wide range of geochemical methods may be used to characterize dolomites and dolostones, and to decipher their origin. The most widely used methods are the analysis and interpretation of stable isotopes (O, C), Sr isotopes, trace elements, and fluid inclusions. Under favourable circumstances some of these parameters can be used to determine the direction of fluid flow during dolomitization. The extent of recrystallization in dolomites and dolostones is much disputed, yet extremely important for geochemical interpretations. Dolomites that originally form very close to the surface and from evaporitic brines tend to recrystallize with time and during burial. Those dolomites that originally form at several hundred to a few thousand metres depth commonly show little or no evidence of recrystallization. Traditionally, dolomitization models in near-surface and shallow diagenetic settings are defined and/or based on water chemistry, but on hydrology in burial diagenetic settings. In this paper, however, the various dolomite models are placed into appropriate diagenetic settings. Penecontemporaneous dolomites form almost syndepositionally as a normal consequence of the geochemical conditions prevailing in the environment of deposition. There are many such settings, and most commonly they form only a few per cent of microcrystalline dolomite(s). Many, if not most, penecontemporaneous dolomites appear to have formed through the mediation of microbes. Virtually all volumetrically large, replacive dolostone bodies are post-depositional and formed during some degree of burial. The viability of the many models for dolomitization in such settings is variable. Massive dolomitization by freshwater-seawater mixing is a myth. Mixing zones tend to form caves without or, at best, with very small amounts of dolomite. The role of coastal mixing zones with respect to dolomitization may be that of a hydrological pump for seawater dolomitization. Reflux dolomitization, most commonly by mesohaline brines that originated from seawater evaporation, is capable of pervasively dolomitizing entire carbonate platforms. However, the extent of dolomitization varies strongly with the extent and duration of evaporation and flooding, and with the subsurface permeability distribution. Complete dolomitization of carbonate platforms appears possible only under favourable circumstances. Similarly, thermal convection in open half-cells (Kohout convection), most commonly by seawater or slightly modified seawater, can form massive dolostones under favourable circumstances, whereas thermal convection in closed cells cannot. Compaction flow cannot form massive dolostones, unless it is funnelled, which may be more common than generally recognized. Neither topography driven flow nor tectonically induced ( squeegee-type') flow is likely to form massive dolostones, except under unusual circumstances. Hydrothermal dolomitization may occur in a variety of subsurface diagenetic settings, but has been significantly overrated. It commonly forms massive dolostones that are localized around faults, but regional or basin-wide dolomitization is not hydrothermal. The regionally extensive dolostones of the Bahamas (Cenozoic), western Canada and Ireland (Palaeozoic), and Israel (Mesozoic) probably formed from seawater that was pumped' through these sequences by thermal convection, reflux, funnelled compaction, or a combination thereof. For such platform settings flushed with seawater, geochemical data and numerical modelling suggest that most dolomites form(ed) at temperatures around 50-80 {degrees}C commensurate with depths of 500 to a maximum of 2000 m. The resulting dolostones can be classified both as seawater dolomites and as burial dolomites. This ambiguity is a consequence of the historical evolution of dolomite research

Linear model describing three components of flow in karst aquifers using O-18 data, 2004, Long A. J. , Putnam L. D. ,
The stable isotope of oxygen, 180, is used as a naturally occurring ground-water tracer. Time-series data for 5 180 are analyzed to model the distinct responses and relative proportions of the conduit, intermediate, and diffuse flow components in karst aquifers. This analysis also describes mathematically the dynamics of the transient fluid interchange between conduits and diffusive networks. Conduit and intermediate flow are described by linear-systems methods, whereas diffuse flow is described by mass-balance methods. An automated optimization process estimates parameters of lognormal, Pearson type III, and gamma distributions, which are used as transfer functions in linear-systems analysis. Diffuse flow and mixing parameters also are estimated by these optimization methods. Results indicate the relative proximity of a well to a main conduit flowpath and can help to predict the movement and residence times of potential contaminants. The three-component linear model is applied to five wells, which respond to changes in the isotopic composition of point recharge water from a sinking stream in the Madison aquifer in the Black Hills of South Dakota. Flow velocities as much as 540 m/d and system memories of as much as 71 years are estimated by this method. Also, the mean, median, and standard deviation of traveltimes; time to peak response; and the relative fraction of flow for each of the three components are determined for these wells. This analysis infers that flow may branch apart and rejoin as a result of an anastomotic (or channeled) karst network. Published by Elsevier B.V

Organic pollutants in stream sediments of Kupa River drainage basin, 2005, Franciskovicbilinski S, Bilinski H, Sirac S,
This paper presents the first results of distribution of organic pollutants in 44 sediment samples (fraction < 63 mu m) of Kupa River drainage basin, which is a significant water resource for Croatia, Slovenia and BiH (Bosnia and Herzegovina). The investigated region aimed to be used as a model for future studies, necessary to meet Decision No. 2455/2001/EC. Some parts of the drainage basin are national parks (Risnjak and Plitvice Lakes). Also, a great part was affected by war 1991-1995 and is still under mines, what makes it difficult to sample. Sediments have shown a good record of pollution. Concentrations of total polychlorinated biphenyls (PCBs) were found above toxic levels (> 0.02 ppm) for 7 sediment samples. Total phenols were determined above 0.65 ppm for 23 sediment samples, which was characterized as heavily polluted sites. Mineral oils above 100 ppm were found in 13 sediment samples, which are, therefore, moderately polluted. Total lindane isomers in all sediments were below the detection limit of 0.0004 ppm, and, therefore, far below the toxic level of 0.0009 ppm. Results have shown unexpectedly that the western part of Kupa River drainage basin, with karst aquifers of high risk located in the boarder area of Croatia and Slovenia, has sediments, which were more polluted with organic contaminants from those affected by the war in the middle and eastern part of the basin. Further studies of sediments and protection of karst aquifers in this region is suggested

Ice caves as an indicator of winter climate evolution: a case study from the Jura Mountains, 2005, Luetscher Marc, Jeannin Pierre Yves, Haeberli Wilfried,
Subsurface ice fillings were first described in the Jura Mountains at the end of the sixteenth century. In order to assess the impact of climate change on low-altitude cave ice a detailed inventory has been drawn up and more than 50 objects have been identified. Comparisons between older cave maps, photographic documents and present-day observations outline a negative trend in ice mass balances, a trend that increased at the end of the 1980s. As most of these ice caves act as cold air traps, this negative mass balance is mainly attributed to higher winter temperatures and to reduced snow precipitation at low altitudes. The equilibrium line altitude of ice caves is believed to have increased several hundred metres between AD 1978 and 2004. Photographic comparisons and proxy records in some of the caves studied provide evidence of a rapid mass turnover. Ice ages range between less than a few decades and a millennium. Climatic records in these ice fillings will therefore present only short time series compared with other cave sediments. However, indications of former ice fillings have been found in different caves of the Jura Mountains and outline their potential role as palaeoclimatic markers

Hydrogeochemical balance sheet of natural and anthropogenic impacts onto Orleans valley karstic network performed with major elements : the 'dynamic confinement' model quantification, 2006, Le Borgne Francois, Treuil Michel, Joron Jean Louis, Lepiller Michel,
The Orleans valley aquifer comprises both the alluvia of the Loire river and its underlying calcareous stratum. This aquifer is fed by river recharge, thanks to a substantial karstic network in its calcareous part. The main outlets of the aquifer are the Loiret springs, including the famous 'le Bouillon' spring. As a result, entries and exits of Orleans valley watertable make a natural observatory, allowing study of the transit of the chemical species inside the aquifer. Since 1997, this natural observatory has been improved with the installation of 52 piezometers (37 in the alluvial aquifer and 15 in the carbonate aquifer) within an alluvial quarry located in the middle of Orleans valley. Tracer experiments, carried out in this extended observatory, have shown that the porous calcareous and alluvial part of the aquifer constitute a 'dynamically confined system'. As a result, the hydrochemical input of the porous domain of the aquifer to the karstic flow must be negligible. The aim of this study is to confirm this theory with the use of major elements as large-scale temporal and spatial tracers of these exchanges. At 'le Bouillon' karstic spring, the Na, K, Mg2, Cl- and SO42- concentrations are closely correlated to those of the Loire river if a 3-4 day time lag is considered. This indicates a quasi-conservative transit of these elements in the karst. Conversely, calcite dissolution accompanying the organic matter biodegradation induces significant enrichments in Ca2, HCO3- and NO3- (mean annual concentrations of which are, respectively, 27.0, 87.8 and 4.9 mg.L-1 in the Loire river and 37.3, 127 et 7.3 mg.L-1 at 'le Bouillon' spring). After fertiliser spreading, the alluvial waters are highly enriched in NO3-, Cl-, SO42- (respectively 67.2, 24.0, 57.5 mg.L-1) compared to the Loire river (respectively 5.5, 12.7, 17.5 mg.L-1). The anthropogenic input is insignificant for Na, of which the average concentration in the alluvial watershed (11.7 mg.L-1) remains close to the Loire river (12.9 mg.L-1). The alluvial watershed is depleted in K (1.3 mg.L-1) with respect to the Loire river (3.7 mg.L-1) and correlatively enriched in Mg2 (17.0 mg.L-1 against 5.0 mg.L-1). High major element concentrations are measured in several calcareous piezometers confirming that vertical flows occur between the alluvial and calcareous parts of the aquifer. Furthermore, enrichment heterogeneity in those two strata is induced by a dynamic redistribution, with no significant leaching of anthropogenic inputs which were previously homogeneously spread. This redistribution is pulsed by ascents of the Loire river, impacts of which on the watershed are clearly identified on Mg/K-Na/K diagrams showing a main K {leftrightarrows} Mg exchange between Loire water and clays minerals. Taking into account average K and Mg concentrations in the different parts of Orleans valley's watershed, the volume of porous aquifer water brought to the karstic network flow mean estimated is 2.4 % of the total volume which transits between the Loire and the 'le Bouillon' spring, showing the dynamic confining action of the aquifer porous domain. Taking into account more precisely seasonal river Loire and spring composition variation, these inputs can be more precisely established : 1.6% during winter and 1.2% during summer at 'Le Bouillon' spring; 2.4% during winter and 3.9% during summer at 'La Pie' spring. But such a weak global contribution of the porous domain accounts for 10% nitrate composition of the karstic springs. Seasonal spring nitrate composition balance is clearly explained by 60% river Loire, 30 % organic matter oxydation - carbonate dissolution and 10% porous domain inputs during winter, and 30% river Loire, 60% organic matter, - carbonate dissolution and 10% porous domain inputs. Same calcium mass balance calculations point out the necessity of CO2 winter complementary input by local rain fall penetrations

IDENTIFYING PALEO WATER-ROCK INTERACTION DURING HYDROTHERMAL KARSTIFICATION: A STABLE ISOTOPE APPROACH, 2009, Dublyansky Y. , Spotl C.

Haloes of altered oxygen isotope values ranging in size from < 1 m to several km have been reported around hydrothermal ore deposits. We have found that similar alteration zones could be induced by lukewarm to thermal cave-forming waters. A paleo wall in Entrische Kirche cave (Gastein Valley, Austrian Alps) preserved a 5 cm-thick brownish zone behind a thick flowstone. Across this zone the O isotope values gradually increase by 11 ‰, until they reach values characteristic of the unaltered marble. The isotope composition in the alteration zone is very different from that of the ?owstone above but is similar to phreatic calcite spar from hypogene (thermal) karst cavities in surface outcrops in the area. We interpret this isotopic pro?le as re?ection of the water-rock interaction in a low-temperature hydrothermal karst system. Similar alteration pro?les were found around solutional cavities at Hllenstein (Tux Valley, Austrian Alps), lined with hydrothermal calcite. Sigmoid shapes of isotope profiles suggest that the most-altered bedrock was isotopically equilibrated with paleo waters. This allows use of isotope mass-balance calculations to assess the temperature of the paleo waters. Isotope profiles acquired from a number of other hypogene caves in Austria failed to show any isotopic signals of bedrock alteration.


Geochemical and statistical evidence of recharge, mixing, and controls on spring discharge in an eogenetic karst aquifer, 2009, Moore Paul J. , Martin Jonathan B. , Screaton Elizabeth J.

Information about sources of recharge, distributions of flow paths, and the extent of water–rock reactions in karst aquifers commonly result from monitoring spring chemistry and discharge. To investigate the relationship between spring characteristics and the complexities of karst aquifers, we couple variations in surface- and groundwater chemistry to physical conditions including river stage, precipitation, and  evapotranspiration (ET) within a sink-rise system through a 6-km portion of the Upper Floridan aquifer (UFA) in north-central Florida. Principal component analysis (PCA) of time series major-element compositions suggests that at least three sources of water affect spring discharge, including allogenic recharge into a swallet, diffuse recharge through a thin vadose zone, and water upwelling from deep within the aquifer. The deep-water source exerts the strongest influence on water chemistry by providing a majority of Na+, Mg2+, K+, Cl, and SO2 4 to the system. Anomalously high temperature at one of several monitoring wells reflects vertical flow of about 1 m/year. Mass-balance calculations suggest diffuse recharge and deep-water upwelling can provide up to 50% of the spring discharge; however, their contributions depend on head gradients between the conduit and surrounding aquifer matrix, which are influenced
by variations in precipitation, ET, and river stage. Our results indicate that upwelling from deep flow paths may provide significant contributions of water to spring discharge, and that monitoring only springs limits interpretations of karst systems by masking critical components of the aquifer, such as water sources and flow paths. These results also suggest the matrix in eogenetic aquifers is a major pathway for flow even in a system dominated by conduits.


Holocene glacier history from alpine speleothems, Milchbach cave, Switzerland, 2011, Luetscher M. , Hoffmann D. L. , Frisia S. , Spö, Tl C.

Mountain glaciers and their sediments are prominent witnesses of climate change, responding sensitively to even small modifications in meteorological parameters. Even in such a classical and thoroughly studied area as the European Alps the record of Holocene glacier mass-balance is only incompletely known. Here we explore a novel and continuous archive of glacier fluctuations in a cave system adjacent to the Upper Grindelwald Glacier in the Swiss Alps. Milchbach cave became partly ice-free only recently and hosts Holocene speleothems. Four coeval stalagmites show consistent petrographic and stable isotopic changes between 9.2 and 2.0ka which can be tied to abrupt modifications in the cave environment as a result of the closing and opening of multiple cave entrances by the waxing and waning of the nearby glacier. During periods of Holocene glacier advances, columnar calcite fabric is characterized by 18O values of about 8.0 indicative of speleothem growth under quasi-equilibrium conditions, i.e. little affected by kinetic effect related to forced degassing or biological processes. In contrast, fabrics formed during periods of glacier minima are typical of bacterially mediated calcite precipitation within caves overlain by an alpine soil cover. Moreover, 18O values of the bacterially mediated calcite fabrics are consistent with a ventilated cave system fostering kinetic fractionation. These data suggest that glacier retreats occurred repeatedly before 5.8ka, and that the amplitudes of glacier retreats became substantially smaller afterwards. Our reconstruction of the Upper Grindelwald Glacier fluctuations agrees well with paleoglaciological studies from other sites in the Alps and provides a higher temporal resolution compared to traditional analyses of peat and wood remains found in glacier forefields.


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