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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 aquifer system is a body of permeable and poorly permeable material that functions regionally as a water-yielding unit; it comprises two or more permeable beds separated at least locally by confining beds that impede ground-water movement but do not greatly affect the regional hydraulic continuity of the system; includes both saturated and unsaturated parts of permeable material [22].?

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Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
See all featured articles
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 input (Keyword) returned 185 results for the whole karstbase:
Showing 31 to 45 of 185
Bacteria in the Castleton karst, Derbyshire, England, 1997, Tranter J. , Gunn J. , Hunter C. , Perkins J. ,
The Castleton area contains an extensive and complex karst drainage system. Recharge is provided by allogenic stream sinks and by infiltration into a soil covered autogenic catchment. Concentrations of the sanitary indicator bacteria faecal coliform (FC) were measured weekly over a 84-week period at three stream-sinks (P6, P7 and P8) and at two contrasting springs (Russet Well and Peak Cavern Rising). Russet Well drains the allogenic catchment, but also receives some autogenic recharge whereas Peak Cavern Rising receives only autogenic recharge except at high stage when it functions as an overflow spring for the Russet Well system. Over the year as a whole and during each three-month season, median FC concentrations at P6 were significantly higher than at Russet Well. The difference was greatest during summer/autumn and was lowest in winter/spring and it appears that FC concentrations at the rising are a complex function of faecal inputs and flow-through time. The relationship between FC concentrations at Russet Well and at Peak Cavern Rising proved to be complex. Over the sampling period as a whole and during the spring and autumn there was no significant difference between median FC concentrations at the two risings; during the winter, when discharge was highest, median FC concentrations at Russet Well were significantly higher than at Peak Cavern Rising; and during the summer FC concentrations at Peak Cavern Rising were significantly higher than at Russet Well. The high FC concentrations in the sinking streams and at the risings suggest that there could be a health risk to cavers, especially during storm events and the summer. Furthermore, the fact that the waters from both springs contain significant concentrations of FC bacteria indicates that even soil covered karat systems are unable to filter out potentially harmful micro-organisms

Groundwater Geochemistry of Isla de Mona, Puerto Rico, 1998, Wicks C. M. , Troester Jo. W.
In this study, we explore the differences between the hydrogeochemical processes observed in a setting that is open to input from the land surface and in a setting that is closed with respect to input from the land surface. The closed setting was a water-filled passage in a cave. Samples of groundwater and of a solid that appeared to be suspended in the relatively fresh region of saline-freshwater mixing zone were collected. The solid was determined to be aragonite. Based on the analyses of the composition and saturation state of the groundwater, the mixing of fresh and saline water and precipitation of aragonite are the controlling geochemical processes in this mixing zone. We found no evidence of sulfate reduction. Thus, this mixing zone is similar to that observed in Caleta Xel Ha, Quintana Roo, also a system that is closed with respect to input from the land surface.The open setting was an unconfined aquifer underlying the coastal plain along which four hand-dug wells are located. Two wells are at the downgradient ends of inferred flowpaths and one is along a flowpath. The composition of the groundwater in the downgradient wells is sulfide-rich and brackish. In contrast, at the well located along a flow line, the groundwater is oxygenated and brackish. All groundwater is oversaturated with respect to calcite, aragonite, and dolomite. The composition is attributed to mixing of fresh and saline groundwater, CO2 outgassing, and sulfate reduction. This mixing zone is geochemically similar to that observed in blue holes and cenotes.

An investigation, using the chalk karst of Haute-Normandie (France), as an example of the relationships between the surface and endokarst using a granulometric method, 1998, Lacroix M. , Leboulanger T. , Wang H. Q. , Feeny V. , Dupont J. P. , Meyer R. ,
Karst, by definition, is the result of rock dissolution. Ii the rock is not completely soluble, residues will remain ('acquired' particles). This insoluble material, present in the springs issuing From the karst body after some time lag, provides information regarding karst processes taking place within the rock body. The presence of pathways between the surface and the endokarst is reflected by an increase in the suspended particulate material (SPM) that may be considered to be 'inherited' from outside of the karst system, By the study of microgranulometric spectra the origins of the particles are differentiated and, on this basis, a classification of karst systems is proposed. The technique was applied to the chalk karat of Haute Normandie (France) by obtaining characterisations of the microgranulometric fraction of the main surface formations (clay-with-flints and loess) and that produced by dissolution of the chalk. By the comparison of these spectra with those of the SPM contained in ten karst springs, it was possible to define two types of karsts ('open' and 'closed') and their intermediates. In 'closed' karst a majority of the particles originated from the dissolution of the chalk itself, while in the 'open' karst, the majority of the particles are derived from the surface formations. This notion of 'aperture' is quite different from the conventional allogenic/authigenic karst classification which implies the formation of an impermeable residual soil that focuses surface water inputs

Mise en evidence des relations surface-endokarst par la microgranulometrie, exemple du karst crayeux haut-normand, 1998, Lacroix Michel, Leboulanger Thierry, Wang Huaqing, Feeny Veronique, Dupont Jean Paul, Meyer Robert,
Karst, by definition, is the result of rock dissolution. If the rock is not completely soluble, residues will remain ('acquired' particles). This insoluble material, present in the springs issuing from the karst body after some time lag, provides information regarding karst processes taking place within the rock body. The presence of pathways between the surface and the endokarst is reflected by an increase in the suspended particulate material (SPM) that may be considered to be 'inherited' from outside of the karst system. By the study of microgranulometric spectra the origins of the particles are differentiated and, on this basis, a classification of karst systems is proposed. The technique was applied to the chalk karst of Haute Normandie (France) by obtaining characterisations of the microgranulometric fraction of the main surface formations (clay-with-flints and loess) and that produced by dissolution of the chalk. By the comparison of these spectra with those of the SPM contained in ten karst springs, it was possible to define two types of karsts ('open' and 'closed') and their intermediates. In 'closed' karst a majority of the particles originated from the dissolution of the chalk itself, while in the 'open' karst, the majority of the particles are derived from the surface formations. This notion of 'aperture' is quite different from the conventional allogenic/authigenic karst classification which implies the formation of an impermeable residual soil that focuses surface water inputs

Precipitation and alteration of late Cretaceous sedimentary apatites and siderites (Leonie Trough, Bavaria, Germany), 1998, Sattler C. D. , Halbach P. ,
Late Cretaceous sedimentary siderites and fluorapatites of the iron ore deposit 'Leonie' (Bavaria, Germany) have been investigated by geochemical and mineralogical methods to define their origin. The siderites consist to more than 90 mol% of FeCO3. This elemental composition relates to an early diagenetic fresh water depositional environment. The stable isotope geochemistry of carbon and oxygen (delta(18)O: parts per thousand SMOW; delta(13)C: -12 parts per thousand PDB) also supports a siderite genesis in meteoric waters, with carbon originating from oxidation of organic matter. The chemical composition of the fluorapatites is relatively pure and shows a very low elemental substitution for calcium and phosphate. This is the result of an intense epigenetic alteration of the primary carbonate fluorapatite and, thus, cannot be related to specific source aspects. Microscopic investigations and thermodynamic calculations reveal a precursory apatite precipitation before siderite was formed. This process is thought to have removed calcium from karst waters to a level which enables siderite to be precipitated. Because of the data and observations a siderite formation in a stagnant fresh water basin is postulated, while the apatite formation probably was initiated during a connection to the open ocean (Tethys) with temporary marine ingressions. The input of iron and partly of phosphorus and fluorine into the karst basins resulted from the draining of the uplifted easterly mountains of the igneous Bohemian Massif under the influence of a humid warm climate. During the postulated marine ingressions especially phosphorus and fluorine were brought into the system whereas most of the calcium and carbonate reached the karst troughs by dissolution of the Late Jurassic Maim limestones

Monitoring of percolation water to discriminate surficial inputs in a karst aquifer, 1998, Covelli S, Cucchi F, Mosca R,

Contribution of correlation and spectral analyses to the regional study of a large karst aquifer (Charente, France), 1998, Larocque M. , Mangin A. , Razack M. , Banton O. ,
The purpose of the study is to demonstrate that correlation and spectral analyses can contribute to the regional study of a large karst aquifer. An example is presented for the La Rochefoucauld karst aquifer (Charente, France). Different types of spatially distributed time series provide valuable spatio-temporal information for the karat aquifer. The available time series consist of the spring flow rates, the flow rates at different locations in sinking streams, the piezometric levels, the electrical conductivity and temperature of the water, the atmospheric pressure and the precipitation The analysis of the flow rates at the springs shows that the aquifer empties very slowly and has a large storage capacity. Hydrodynamic links were established between three of the four rivers flowing on the aquifer and the springs. The results also demonstrate the important spatial heterogeneity of the aquifer and indicate that the most rapid flow occurs in the northern part of the aquifer. Hourly piezometric and electrical conductivity time series indicate that the transmissivity of the aquifer varies when some conductive channels become desaturated during the low water period. The delays between the distributed recharge and the piezometric level, between the localized river input and the how rates at the springs and between the electrical conductivities in rivers and the main spring provide information on the travel times in the aquifer, The observation of earth tides and barometric effects indicate that this apparently unconfined aquifer has a confined behaviour. (C) 1998 Elsevier Science B.V. All rights reserved

Seasonal Effects on the Geochemical Evolution of the Logsdon River, Mammoth Cave, Kentucky., 1998, Anthony, Darlene M. , Ms

The following research describes the collection and evaluation of geochemical data from the Logsdon River, an open-flow conduit that drains a portion of the Turnhole Spring drainage basin within the Mammoth Cave karst aquifer of south-central Kentucky. This spatial survey of nearly 10 km of continuous base-level conduit included seasonal sampling of carbon dioxide partial pressures (PCO2), dissolved ions, and saturation indices for calcite (SIcal). The highest PCO2 are found at the upstream site closest to the Sinkhole Plain recharge area, which creates undersaturated conditions. Rapid outgassing of CO2 into the cave atmosphere creates oversaturated conditions for several thousand meters. This change in chemistry results in the accumulation of travertine in these areas. A boost in PCO2 roughly half-way through the flow path returns the water to slightly undersaturated conditions. The most likely source for additional CO2 is in-cave organic decay, as the boost also occurs during winter months when microbial activity in the soil is at a minimum. A general decline in Ca2+, Mg2+, and HCO3- concentrations occurred over the distance through the Logsdon River conduit. This decline may reflect a diluting of water by localized inputs from the Mammoth Cave Plateau and precipitation of travertine along the flow path. Although values for all parameters are greater in summer than winter, the trend in evolution is similar for both seasonal extremes.
The nature of the transition from summer to winter conditions in the aquifer was investigated by way of an intensive study of the geochemistry at the Logsdon River monitoring well. The relationship between conductivity (spC) and pH was evaluated during both seasons in an attempt to predict the activity of hydrogen for any given water sample, based on continuous spC measurements at the well. Data collected during the 1997-98 seasonal transitions supported a single, nonlinear regression equation that may represent two distinct seasonal regimes.


Contribution to knowledge of gypsum karstology, PhD thesis, 1998, Calaforra Chordi, J. M.

The objective of this study was not to establish a definitive judgement regarding a topic for which very little previous information was available, but rather to open new routes for research into karst by means of a particularized analysis of some of the factors involved in the speleogenesis of gypsiferous materials. The main obstacle to the attainment of this goal has been the scientific community's lack of interest in karst in gypsum, particularly in our country, until the nineteen eighties. To overcome this neglect it was decided, in my opinion quite correctly, to extend the bounds of the study as far as possible, so that the information obtained from the contrast found between the most important worldwide zones of karst in gypsum could be applied to the gypsiferous karst in our country, and in particular, to the most significant, the karst in gypsum of Sorbas.
This is the justification for the numerous references in the text to the gypsiferous karst and cavities in gypsum that are most relevant in Spain (Sorbas, Gobantes, Vallada, Archidona, Estremera, Baena, the Ebro Basin, Estella, Beuda, Borreda, etc.) and also to the best-known gypsiferous karsts worldwide (Podolia, Secchia, Venna del Gesso Romagnolo, Sicily and New Mexico). By means of these comparisons, the initial lack of information has been overcome.
The study is based on three central tenets, which are interrelated and make up the first three chapters of this report. The first consideration was to attempt to characterize the particular typology of gypsiferous karst from the geological (both stratigraphic and structural) point of view. This chapter also provides an introduction to each of the gypsiferous karsts examined. The second chapter is dedicated to the geomorphology of gypsiferous karst, under both superficial and subterranean aspects. It is important to note that the study of a gypsiferous karst from the speleological point of view is something that may seem somewhat unusual; however, this is one of the points of principle of this paper, the attempt to recover the true meaning of a word that has historically been unfairly condemned by a large part of the Spanish scientific community. Thirdly, a detailed study has been made of the hydrochemistry of the most important gypsiferous karsts in our region, together with the presentation of a specific analytical methodology for the treatment of the hydrochemical data applicable to the gypsiferous karst.
Geological characterization of gypsum karst
In the characterization of karst in gypsum, the intention was to cover virtually all the possibilities from the stratigraphic and structural standpoints. Thus, there is a description of widely varying gypsiferous karsts, made up of Triassic to Miocene materials, some with a complex tectonic configuration and others hardly affected by folding. The gypsiferous karsts described, and their most significant geological characteristics, are as follows:
Karst in gypsum at Sorbas (Almeria): composed of Miocene gypsiferous levels with the essential characteristic of very continuous marly interstrata between the layers of gypsum, which decisively affect the speleogenesis of the area. The gypsum layers have an average thickness of about 10 m and, together with the fracturing in the zone, determine the development of the gypsiferous cavities. These are mainly selenitic gypsum - occasionally with a crystal size of over 2 m - and their texture also has a geomorphologic and hydrogeologic influence. This area is little affected by folding and so the tectonic influence of speleogenesis is reduced to the configuration of the fracturing.
The Triassic of Antequera (Malaga): this is, fundamentally, the gypsiferous outcrop at Gobantes-Meliones, originating in the Triassic and located within the well-known "Trias" of Antequera. It is made up of very chaotic gypsiferous materials containing a large quantity of heterometric blocks of varied composition; the formation may be defined as a Miocene olitostromic gypsiferous breccia that is affected by important diapiric phenomena. The presence of hypersoluble salts at depth is significant in the modification of the hydrochemical characteristics of the water and in the speleogenetic development of the karst.
The Triassic of Vallada (Valencia): Triassic materials outcrop in the Vallada area; these mainly correspond to the K5 and K4 formations of the Valencia Group, massive gypsum and gypsiferous clays. The influence of dolomitic intercalations in the sequence is crucial to the speleogenesis of the area and this, together with intense tectonic activity, has led to the development in this sector of the deepest gypsiferous cavity in the world: the "Tunel dels Sumidors". As in the above case, the presence of hypersoluble salts at depth and the varied lithology influence the variations in the hydrodynamics and hydrochemistry of the gypsiferous aquifer.
Other Spanish gypsum karsts: this heading covers a group of gypsiferous areas and cavities of significant interest from the speleogenetic standpoint. They include the area of Estremera (Madrid), with Miocene gypsiferous clays and massive gypsum arranged along a large horizontal layer; this has produced the development of the only gypsiferous cavity in Spain with maze configuration, the Pedro Fernandez cave. The study of this cave has important hydrogeological implications with respect to speleogenesis in gypsum in phreatic conditions. The Baena (Cordoba) sector, in terms of its lithology, is comparable to the "Trias de Antequera". Here, the cavities developed in gypsiferous conglomerates, following structural discontinuities have enabled contact between carbonate and gypsiferous levels, and so we may speak of a mixed karstification: a karst in calcareous rocks and gypsum. The karst of Archidona (Malaga) is similar to that of the Gobantes-Meliones group and is significant because of the geomorphologic evolution of the karst, which is related to the diapiric ascent of the area and the formation of karstic ravines. The karst in the Miocene and Oligocene gypsum of the Ebro Basin (Zaragoza), has been taken as a characteristic example of a gypsiferous karst developed under an alluvial cover, with the corresponding geomorphological implications in the evolution of the surface landforms. In the gypsiferous area of Borreda (Barcelona), the presence of anhydritic levels in the sequence might have influenced the speleogenesis of its cavities. The cavity of La Mosquera, in Beuda (Girona), developed in massive Paleogene gypsum. This is the only Spanish example of a phreatic gypsiferous cavity developed in saccaroid gypsum, which is related to the particular subterranean morphology discovered. Finally, this group includes other Spanish gypsiferous outcrops visited during the preparation of this report, the references to which may be found in the relevant chapters.
Karst in gypsum in Europe and America: In order to complete the study of karst in gypsum, and with the idea of using all the available data on the karstology of gypsiferous materials for comparative studies of data for our country, a complementary activity was to define the most significant geological characteristics of the most important gypsiferous karsts in the world. An outstanding example is the gypsiferous karst at Podolia (Ukraine), developed in microcrystalline Miocene gypsum which has undergone block tectonics related to the collapse of the Precarpatic foredeep. This gypsum provides interesting data on speleogenesis in gypsiferous materials, as its evolution is related to the confining of the only gypsiferous stratum (of 10 to 20 m depth) producing interconnected labyrinthine galleries of over 100 km in length. Another well-known karst in gypsum is the one located at "Venna del Gesso Romagnolo" (Italy), in the Bologna region, with a lithology that is very similar to that which developed at Sorbas, but with the difference that it underwent more intense tectonics with folding and fracturing of the Tertiary sediments of the Po basin. In the same Italian province, in "L'alta Val di Sec-chia", there are outcrops of karstified Triassic materials which correspond to the formation of Burano, composed of gypsum and anhydrite with hypersoluble salts at depth and very notable diapiric phenomena. The study of this area has been used for a comparative analysis - geomorphology and hydrogeochemistry - with the Spanish gypsiferous karsts developed in Triassic levels. The third Italian gypsiferous karst to be considered is the one developed in Sicily, which has extensive Messinian outcrops of microcrystalline and selenitic gypsum as well as a great variety of lithologic types within the gypsiferous sequence, which we term the "gessoso solfifera" sequence. This gypsiferous karst is especially interesting from the geomorphologic standpoint due to the great quantity and variety of present superficial karstic forms. This has also served as a guide for the study of Spanish gypsiferous karsts. Finally, considering the relation between climatology and the development of karstic forms, we have also studied the karst in gypsum in New Mexico, where there is an extensive outcrop of Permian gypsum, both micro and macrocrystalline, situated on a large platform almost unaffected by deformation, and where the conditions of aridity are very similar to those found in the gypsiferous karst of Sorbas.
Geomorphological characterization of gypsum karst
From the geomorphological standpoint, the intention is to give an overview of the great variety of karstic forms developed in gypsum, traditionally considered less important than those developed in carbonate areas. This report shows this is not the case.
The theory of Convergence of Forms has been shown to be an efficient tool for the study of the morphology of karst in gypsum. Here, its principles have been used to provide genetic explanations for various gypsiferous forms derived from carbonate studies, and for the reverse case. In fact, studying a karst in gypsum is like having available a geomorphological laboratory where not only are the processes faster but they are also applicable to the karstology of carbonate rocks.
A large number of minor karstic forms (Karren) have been identified. The most important factors conditioning their formation are the texture of the rock, climatology and the presence of overlying deposits. The first, particularly, is largely responsible for determining the abundance of certain forms with respect to others. Thus, Rillenkarren, Trittkarren and small "kamenitzas" are more frequently found in microcrystalline and sandstone gypsum (for example, karst in gypsum in Sicily (Italy) and Va-llada (Valencia, Spain). Others seem to be more exclusive to selenitic gypsum, such as exfoliation microkarren, or are closely related to the climatology of the area (Spitzkarren develops from the alteration of gypsum in semiarid conditions). Others are related either to the presence of developed soil cover (Rundkarren, using Convergence of Forms), or to their specific situation (candelas and Wallkarren around dolines and sinkholes) or to the microtexture of the gypsum and the orientation of the 010 and 111 crystalline planes and twinning planes for the development of nanokarren.
The tumuli are the most peculiar forms of the Sorbas karst in gypsum, though they have also been identified in other gypsiferous karsts (Bolonia, New Mexico, Vallada, etc.). These are subcircular domes of the most superficial layer of the gypsum. Their formation has been related to processes of precipitation-solution and of capillary movement through the gypsiferous matrix. Their extensive development is largely determined by the climatology of the area and by the structural organization. It is therefore clear that the best examples are found in the karst of Sorbas due to the abrupt changes in temperature and humidity that occur in a semiarid climate, and because of the horizontality of the gypsiferous sequence.
Karst in gypsum and its larger exokarstic forms, apart from being climatically determined, also depend on the structural state and lithological determinants of the area. Thus, it is possible to differentiate between gypsiferous karsts where the lithology, together with erosive breakup, is more important (Sorbas and New Mexico) and others where confining hydraulic conditions persist (Estremera and Podolia). In other cases, tectonics has played a significant modelling role, and there is a clear possibility of an inversion of the relief (Bolonia or Sicily) or of the effect of diapiric processes (Secchia, Vallada, Antequera). The typological diversity of the dolines is obviously also related to these premisses. Another example is the relation existing between carbonate precipitation and gypsum solution, as evidenced in contrasting examples (Bolonia versus Sorbas).
Subterranean karstic forms have been examined from a double perspective: the morphology of the passages and the mineralization within the cavities. With respect to the former, a noteworthy example is the interstratification karst of Sorbas, where subterranean channels have developed during two well-differentiated phases, the phreatic and the vadose. The first was responsible for the formation of the small proto-galleries, currently relicts that are observable as false dome channels in the bottom of the gypsiferous strata. The second, with an erosive character, enabled the breakup of the marly interstrata and the formation of the large galleries found today. Other aspects considered include the speleogenetic influence of the presence of calcareous intercalations in the gypsiferous sequence (Vallada karst), gypsiferous agglomerates (Baena karst), anhydrite (Rotgers karst), suffusion processes (Sorbas karst) and the importance of condensation.
Spelothemes in gypsiferous cavities have been approached with special concern for gypsiferous speleothemes, in particular those which, due to their genetic peculiarity or to the lack of previous knowledge about them, are most significant. Among these are gypsum balls, with phenomena of solution, detritic filling, capillarity and evaporation; gypsum hole stalagmites, where the precipitation-solution of the gypsum controlling the formation of the central orifice is related to the previous deposit of carbonate speleothemes; gypsum trays that mark the levels of maximum evaporation; gypsum dust, determined by abrupt changes in temperature and humidity in areas near the exterior of gypsiferous cavities. All of these are characteristic of, and practically exclusive to, gypsiferous karsts in semiarid ztenes such as Sorbas and New Mexico.
Karst in gypsum has been morphologically classified with reference to the previously-mentioned criteria: the presence and typology of epigean karstic forms, both macro and microform; the typology of hypogean karstic forms (passages) and the type of speleothemes within the cavities (gypsiferous or carbonate). All these variables are clearly influenced by climatology, and so a study of the geomorphology of gypsiferous karst is seen to be an efficient tool for the analysis of the paleoclimatology of an area.
Hydrogeochemical characterization of gypsum karst
The hydrogeochemical characterization of karst in gypsum was approached in two stages. The first one was intended to establish themodels to be applied to the hydrochemistry approach, while the second provided various examples of hydrochemical studies carried out in gypsiferous karsts.
The theoretical framework which has been shown to be most accurate with respect to the formulation of chemical equilibria in water related to gypsiferous karst is the Virial Theory and the Pitzer equations.
For this study, we used a simplification of these equations as far as the second virial coefficient by means of a simple, polynomial variation to obtain the equilibrium state of the water with respect to the gypsum, for an ionic strength value greater than 0.1 m and temperatures of between 0.5 and 40 "C. This was the case of the gypsiferous karsts found to be related to hypersaline water at depth (Vallada, Gobantes-Meliones, Poiano). In the remaining situations, where the ionic strength was below 0.1 m, only the theory of ionic matching was used.
The hydrochemical study of the gypsiferous karst of Gobantes-Meliones (Malaga) led to the hypothesis of the possible influence of hypersaline water on karstification in gypsum. Using theoretical examples of the mixing of water derived both from hypersaline water and from water related only to the gypsiferous karst, it was shown that above a percentage content of 0.1:0.9 of saline and sulphated water, the mixture is subsaturated with respect to gypsum and other minerals. On reaching percentages greater than 0.5:0.5, values of oversaturation are again found. This could mean that the contact between sulphated and hypersaline water is a karstification zone in gypsum at depth.
In the gypsiferous karst at Salinas-Fuente Camacho (Granada), a study has been made of the hydrochemical influence of dolomitic levels in the sequence by means of the analysis of the hydrochemical routes between hydraulically-connected points. The generic case of mass transfer in this gypsiferous aquifer implies a precipitation of calcite which is in-congruent with dolomitic solution, proving that the process of dedolomitization in gypsiferous aquifers with an abundance of dolomitic rocks can be an effective process. In situations of high salinity, with contributions of hypersaline water, the process may be inverted, such as occurs in coastal carbonate aquifers influenced by the fresh-saltwater interface.
The gypsiferous aquifer of Sorbas-Tabernas (Almeria) provides the best case of karstification in gypsum in Spain; the hydrochemical study carried out has been used as an example of karstification in gypsum completely uninfluenced by sodium-chloride facies. It is shown, from the hydrochemical similarities between the different sectors, that the uniformity of the flow from the system main spring (Los Molinos) responds to the delayed hydraulic input through the overlying post-evaporitic materials and to the pelitic intercalations of the gypsiferous sequence. The aquifer is partially semiconfined, a situation which is comparable to the onset of the karstification stage, while the area of the Sorbas karst, strictly speaking, bears no hydriaulic relation to the rest of the system, behaving like a free aquifer intrinsically related to the epikarstic zone. This fact is demonstrated by the hydrochemical differences between the main spring and those related to gypsiferous cavities.
Apart from the general study of the Sorbas-Tabemas aquifer, a study was also made of the hydrochemical-time variations within cavities, and in particular within the Cueva del Agua, where it is possible to observe particular processes affecting karstification in gypsum, such as the precipitation of carbonates on the floor of the cavity which produce, in that area, a greater solution of gypsum (the phenomenon of hyperkarstification). Furthermore, the temporal evolution of the chemistry of the cavity, along 800 m of subterranean flow through its interior, shows the existence of inertial sectors where the variations were less abrupt. Only in the case of particular sectors, related to sporadic hydriaulic contributions or to the proximity to points of access., was a notable seasonal influence detected.
A similar hydrochemical study was carried out in the karst of Vallada (Valencia), along the cavity of the Tunel dels Sumidors. The chemistry here was compared with that of the springs of Brolladors (whose water rapidly infiltrates into the cavity) and Saraella (a saline resurgence of the whole system). Unexpected increases in the ionic content of certain salts (sulphates and chlorides) were detected during periods of increased flow; these were interpreted as the effect of the recharging of the Saraella spring arising from the immediate contribution of rapidly circulating sulfated water coming from the cavity and the subsequent mobilization of interstitial water with an ionic content higher than the characteristic level of the spring.
We present as a hypothesis the idea that, in addition to the hydrogeochemical processes described that can affect the evolution of a gypsiferous karst, the processes of sulphate reduction also influence karstification in gypsum, at least during the earliest stages. Some examples such as the presence of gypsum with abundant organic matter reprecipitated into phreatic channels (Sorbas) or veins of sulphur related to gypsiferous karsts (Podolia, Sicily) lend support to this idea.
Studies of the solution-erosion of gypsum have been performed by physical methods (tablets and M.E.M.) showing that the solution-erosion of gypsum within cavities is minimal (0.03 mm/ year) compared to that existing in the exterior (0.3 mm/year). The speleogenetic effect of condensation within the cavities has also been shown, with solution-erosion rates of 0.005 mm/year to be like the equivalent surface lowering. These data correspond to the karst in gypsum at Sorbas, where, additionally, a study about the time variation of the solution-erosion was carried out. It was found that the process is not continuous but clearly sporadic. During periods of torrential rain, the solution-erosion ranges from a weight loss of 400 mg/cm2/year on the surface of the karst to 75 mg/cm2/year inside the caves, while during the rest of the year the weight loss was barely 1 mg/cm2/year. The physical methods were compared with the results obtained from chemical methods, and it was found that, in general, higher values were obtained with the former (10-20% higher when weighted for the rainfall during the measuring periods). Thus it is reasonable to consider that the erosive process is more marked than was at first assumed.
In total, three cavity tracing experiments were carried out, all with fluoresceine, two of them in Cueva del Agua in Sorbas (during periods of high and low water levels) and the other in Tunel dels Sumidors in Vallada. At the first site, the comparison of the two tracing tests reveals a differential hydrodynamic behaviour of the cavity for the two contrasting situations; periods of high water input and periods of low rainfall. This behaviour is characteristic of well developed karstic aquifers, where the hydrodynamic effect of the circulation of water through small channels or, in this case, through the gypsiferous matrix and interbedded marly layers, seems to be more important under conditions of low hydraulic input than when rainfall is abundant. The two situations tested seem to confirm that the Cueva del Agua system, an epikarstic aquifer, which is representative of karstification in gypsum, has scarce retentive power and so large volumes of precipitation are totally discharged via the spring within a few days. However, the explanation of the small but continuous flow from the base of the cavity requires the inclusion of other factors in the interpretation. In this case, the flow seems to be fairly independent of rainfall and attributable to other processes, in addition to the previously described ones, such as the retentive power of the gypsiferous matrix and the marly interstrata. These might include the high degree of condensation measured over long periods, both on the surface of the karst in gypsum and within the cavities. In the case of the Tunel dels Sumidors, a highly irregular response was found, despite the fact that the coefficient of dispersivity was found to be 0.4. This value is similar to that obtained for the karst in gypsum at Sorbas in response to low water conditions, and so, here too, one might assume the influence of greater than expected flow-retaining processes, between the entry and exit points. Doubtless the karstic system of the Tunel dels Sumidors is more complex than was initially expected and in fact, the irregularity reflected by the fluoresceine concentration curve over time implies the existence of other factors to explain the diversity of the relative maxima obtained. Firstly, the presence of numerous Triassic clay intercalations might delay the flow, in addition to retaining a certain quantity of fluoresceine by ionic exchange. There is also a possibility that the flow is dispersed through a network of small conduits and pores, due to the permeability of the gypsiferous matrix. Finally, we cannot discount the possible existence of a deep-level input which, in this case, would be responsible for the variation in the flow and the chemical composition. This set of suppositions, as a whole, would explain the fact that the response of the spring to tracing is so irregular, even though we cannot achieve a definition of the qualitative influence of each one on the hydrodynamics of the system.
In order to verify some of the above hypotheses, particularly those referring to the process of condensation within cavities, an experiment was designed, consisting of a microtracing test at some points where condensation had been detected within the Cueva del Agua at Sorbas. The test produced a range of condensation flow speed values of 0.2 to 30 cm/hour and shows that, in those sections where the presence of condensation flow is visually apparent, there is a rapid dispersion of the colourant. However, it also shows that at points where there is no apparent condensation the process also occurs, but at a lower rate of efficiency. The importance of condensation within cavities has two aspects; firstly, speleogenetic, with the development of solution forms (cupolas) and deposit forms (capillarity boxwork); and secondly, hydrogeological, as this is the reason why certain processes (strong changes in temperature and humidity, multiple routes of airflow exchange with the exterior) may in themselves constitute a hydraulic contribution, of slight importance, but sufficient to explain a large part of the base flow (0.2 - 0.8 L/s) of a whole cavity system such as the Cueva del Agua in semiarid conditions.
With the intention of completing the analyses carried out in various karsts in gypsum, instruments were installed in the Cueva del Agua at Sorbas to measure, by continuous registration, some important physico-chemical parameters that might provide additional data on the hydro-geologic behaviour of this gypsiferous karst, especially at the level of the epikarstic zone. The parameters of temperature and water conductivity were considered most important, due to their singular behaviour patterns. During the experiment there were two periods of rainfall that modified the chemistry of the cavity, one of 30 mm in two days and another of 200 mm (almost the annual total) in four days. In the second case, which was much more extreme, a very significant increase in water temperature (up to 7 °C during the initial period of high water flow) was detected, while conductivity fell. But suddenly, when the minimum conductivity was reached, the temperature dropped sharply by 6-7 °C to return to the base temperature of the cavity. Subsequently, the temperature again stabilized at about 7 °C above the data recorded during the dry period. This behaviour pattern was not detected when the rainfall was slight. The explanation for this dual behaviour observed is fundamentally based on the quantity of rainfall and on the differences between the exterior air temperature, the temperature of interstitial water and the temperature recorded in the spring during high water flow. When water temperature in the cavity during high water flow is higher than the base temperature recorded in the period immediately before, it means that the interstitial water does not mobilize. However, when at any time the two temperatures coincide, one might suppose that there might have existed a process of mobilization of the water previously resident in the rock, by a piston effect, but in the unsaturated zone. On the other hand, the temporal variations of these parameters during the months following periods of high rainfall have enabled us to detect the existence of distinct periods during the return to normal cavity conditions. By carefully examining the decrease curve of water temperature inside the cavity while conductivity regained its maximum stable value, two periods may be differentiated. The first may be termed the "inertial influence period", when the rainfall occurring removes all signs of natural variation in the cavity. Thus, the daily external influences are not clearly detectable and the curve is downward-sloping and asymptotic with no significant oscillations. In the second period, which ends with the total stabilization of the parameter at the level of the initial conditions, the asymptotic descent is seen to be affected by daily temperature variations. This is termed the "inertial recovery period", during which external variations start to have an effect on the interior of the cavity such that there is a progressive increase in the amplitude of the daily variation in water temperature, air temperature and relative humidity. This behaviour pattern of variation of these parameters during periods of high rainfall, might be extended to all karstic systems, varying only in magnitude and temporal extent.


Limestone ordinances of New Jersey and Pennsylvania: a practitioner's experiences, 1999, Fischer Ja,
Ordinances promulgating land use procedures related to construction in areas underlain by carbonate rocks have been under discussion since the mid-1970s in Pennsylvania and since the mid-1980s in New Jersey. At first, the proposed ordinances only considered ground water contamination then, later included the safety- (or stability) related concerns of constructing in karst areas. The first ordinance addressing both concerns as well as not being so restrictive as to eliminate development is believed to have been passed in Clinton Township, New Jersey in May, 1988. Recently, several other nearby townships have passed ordinances based (either loosely or tightly) upon the 'Model Ordinance' developed by the 'Limestone Committee' of the North Jersey Resource Conservation and Development Council. The Model Ordinance has its roots in the Clinton Township Ordinance. Other ordinances, with little to no geotechnical input, have also been passed (and sometimes repealed) by well-meaning municipalities. As the subsurface conditions are complex and erratic (folded and faulted carbonates), an appropriate site evaluation is difficult to define and generally more costly to perform than a conventional site investigation. With this mix of ordinances, the variability in subsurface conditions and the diverse experience levels of the regional practitioners, the resulting effectiveness of these ordinances is mixed, from the humorous to the very positive. In general, the Clinton Township and Model Ordinance-based legislation, which specify procedures to be used in an investigation, work well. Other ordinances refer to standards which do not exist, have requirements which cannot be met in the real world, or appear poorly related to any realistic geotechnical concepts. This paper will describe some typical examples of projects from the viewpoint of both the reviewer and the submitter. A state-of-the-practice presentation, not necessarily state-of-the-art. (C) 1999 Elsevier Science B.V. All ri hts reserved

Tectonic network as the initial factor of karstification of the chalk limestones in the Perche hills (Orne, Normandy, France), 1999, Rodet J. ,
Tectonics has been known to be the initial factor of karstification for a long time, but this has never been demonstrated because of the progressive nature of karstification, which destroys evidence of the preliminary phases. Because of its dual hydrological quality, chalk limestone has conserved a great variety of specific forms illustrating various steps in evolution, from the initial primokarst to the classic well-developed drain. In the Perche hills, very recent research has shown specific endokarstic galleries, filled up by sands and clays. Physical, chemical and X-ray analyses have shown that such infillings result not from a classical fluviatile deposit process, but on the contrary, from an alteration process, underlining the progress of a weathering front into the limestone mass down to the watertable. The infillings are not sedimentary deposits, but represent a kind of 'shadow rock', a chemical in situ transformation of limestone, without any transport of the solid fraction, The genesis results from the progression of weathering fronts located on the tectonic pattern into the input karst. When the weathering front crosses the watertable, the resulting water mixing produces a chemical reaction capable of opening the original joint. This results in infilled galleries, similar to classical karst drains, which have never known fluviatile drainage. This illustrates the first step in normal karstic evolution, just before a water flux drains the gallery, resulting in a new karstification step: the drained passage. The specificity of the region of the Perche hills is this karat evolution stopped in the first step, illustrating the 'primorkarst' modelling by the researcher, which has never been described before. The conditions for this genesis are a well-developed tectonic pattern, an absence of thick superficial layers, a high soil permeability, and an absence of superficial drainage (lack of sinkholes). (C) Elsevier, Paris

Muddy waters: temporal variation in sediment discharging from a karst spring, 1999, Mahler B. J. , Lynch F. L. ,
Karst aquifers are capable of transporting and discharging large quantities of suspended sediment, which can have an important impact on water quality. Here we present the results of intensive monitoring of sediment discharging from a karst spring in response to two storm events, one following a wet season and the other following a dry season; we describe temporal changes in total suspended solids (TSS), mineralogy, and particle size distribution. Peak concentrations of suspended sediment coincided with changes in aqueous chemistry indicating arrival of surface water, suggesting that much of the discharging sediment had an allochthonous origin. Concentrations of suspended sediment peaked 14-16 h after rainfall, and the bulk of the sediment (approximately 1 metric ton in response to each storm) discharged within 24 h after rainfall. Filtered material included brightly colored fibers and organic matter. Suspended sediments consisted of dolomite, calcite, quartz, and clay. Proportions of each mineral constituent changed as the aquifer response to the storm progressed, indicating varying input from different sediment sources. The hydraulic response of the aquifer to precipitation was well described by changes in parameters obtained from the particle size distribution function, and corresponded to changes seen in TSS and mineralogy. Differences between storms in the quantity and mineralogy of sediment transported suggest that seasonal effects on surface sediment supply may be important. The quantity of sediment discharging and its potential to sorb and transport contaminants indicates that a mobile solid phase should be included in contaminant monitoring and contaminant transport models of karst. Temporal changes in sediment quantity and characteristics and differences between responses to the two storms, however, demonstrate that the process is not easily generalized. (C) 1999 Elsevier Science B.V. All rights reserved

Dedolomitization and other early diagenetic processes in Miocene lacustrine deposits, Ebro Basin (Spain), 1999, Arenas C, Zarza Ama, Pardo G,
A variety of meteoric diagenetic features reveal the development of a syngenetic karst on lacustrine deposits of the Ebro Basin. Diagenetic processes that operated on lacustrine laminated and stromatolitic carbonates include the following. (1) A first syndepositional stage with processes such as dolomitization, desiccation and related breccia formation and sulphate precipitation, either as lenticular gypsum crystals or nodules. This stage took place under progressive evaporation due to lake level fall, when the previous carbonate deposits became exposed as a supra-littoral fringe surrounding saline mud flats of adjacent sulphate depositional environments. (2) A second early diagenetic stage in which processes such as sulphate dissolution and collapse brecciation, dedolomitization, calcite spar cementation and silicification occurred as a result of meteoric water input that caused a progressive rise in lake level. Light isotopic compositions (delta(13)C and delta(18)O) of diagenetic calcites, versus heavier compositions in primary laminated and stromatolitic limestones, confirm a meteoric influence. The syngenetic karst is best developed at the boundary between two allostratigraphic units and coincided with one of the extensive stages of sulphate deposition at the end of the Early Miocene. The karst facies occurred in an area that was a low-relief barrier that separated two sites of sulphate deposition during low lake levels, This indicates that the karat development was controlled by topographic changes within the basin and record a shift from arid to wetter climatic conditions, as suggested by the overlying freshwater carbonate deposits. The presence of diagenetic features such as those described in the central Ebro Basin affecting saline lacustrine carbonates is relevant because they can be used as indicators of subaerial exposure periods in terrestrial environments and they also reveal important palaeogeographic and palaeoclimatic events of basinal extent.

Linear and nonlinear input/output models for karstic springflow and flood prediction at different time scales, 1999, Labat D. , Ababou R. , Mangin A. ,
Karstic formations function as three-dimensional (3D) hydrological basins, with both surface and subsurface flows through fissures, natural conduits, underground streams and reservoirs. The main characteristic of karstic formations is their significant 3D physical heterogeneity at all scales, from fine fissuration to large holes and conduits. This leads to dynamic and temporal variability, e.g, highly variable flow rates, due to several concurrent flow regimes with several distinct response times. The temporal hydrologic response of karstic basins is studied here from an input/output, systems analysis viewpoint. The hydraulic behaviour of the basins is approached via the relationship between hydrometeorological inputs and outputs. These processes are represented and modeled as random, self-correlated and cross-correlated, stationary time processes. More precisely, for each site-specific case presented here, the input process is the total rainfall on the basin and the output process is the discharge rate at the outlet of the basin (karstic spring). In the absence of other data, these time processes embody all the available information concerning a given karstic basin. In this paper, we first present a brief discussion of the physical structure of karstic systems. Then, we formulate linear and nonlinear models, i.e. functional relations between rainfall and runoff, and methods for identifying the kernel and coefficients of the functionals (deterministic vs. statistical; error minimisation vs. polynomial projection). These are based mostly on Volterra first order (linear) or second order (nonlinear) convolution. In addition, a new nonlinear threshold model is developed, based on the frequency distribution of interannual mean daily runoff. Finally, the different models and identification methods are applied to two karstic watersheds in the french Pyrenees mountains, using long sequences of rainfall and spring outflow data at two different sampling rates (daily and semi-hourly). The accuracy of nonlinear and linear rainfall-runoff models is tested at three time scales: long interannual scale (20 years of daily data), medium or seasonal scale (3 months of semi-hourly data), and short scale or 'flood scale' (2 days of semi-hourly data). The model predictions are analysed in terms of global statistical accuracy and in terms of accuracy with respect to high flow events (floods)

Bridging the gap between real and mathematically simulated karst aquifers, 1999, Groves C. , Meiman J. , Howard A. D.
Although several numerical codes have been developed to study the patterns of karst aquifer evolution and behavior, in the current generation of models simplifying assumptions must be made because of incomplete quantitative understanding of key processesA one-year, high-temporal-resolution study of carbonate chemistry with Mammoth Cave's Logsdon River, designed to investigate details of these processes, reveals that limestone dissolution rates vary appreciably over storm and seasonal time scales due to variations in the flux of CO2-rich waters that wash through, and flood, conduits during storm eventsThis undersaturated storm water dissolves rock within a flood zone 25-30 m thickThrough the year, waters were undersaturated only 31% of the timeTime scales of actual karst development may thus be impacted by time-varying processes different from the constant-input chemistry assumed in current published numerical codesA dual approach, coupling quantitative modeling and refinement of the models by careful measurement of processes within real karst aquifers, provides a framework for developing a comprehensive understanding of karst system behavior

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