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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 cave-in is 1. the collapse of the ceiling or side walls of a cave or of the land surface into a subterranean passage as a result of undermining or of pressure from above [10]. 2. the partial or complete collapse of earth material into a large underground opening, such as an excavation or a mine. 3. the sudden slumping of wall material into a pit. 4. a place where material has collapsed or fallen in or down.?

Checkout all 2699 terms in the KarstBase Glossary of Karst and Cave Terms

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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 suspension (Keyword) returned 20 results for the whole karstbase:
Showing 1 to 15 of 20
Karst du Rawyl (Hautes Alpes calcaires de Suisse occidentale), matires dissoutes et en suspension emportes par les sources, 1984, Wildberger, A.
HIGH ALPINE KARST OF RAWYL (SOUTHWESTERN SWITZERLAND): DISSOLVED AND SUSPENDED MATERIALS IN THE WATER OF KARSTIC SPRINGS - The karst of the Rawyl area is located between 1200 and 3250m elevation, at an average height of 2500m. The mean annual rainfall is about 2m. The output of dissolved and suspended material was measured at various important springs, subjected to a glacial to nivo-glacial discharge pattern. The dissolution rate is around 0,06 to 0,075 mm/year of which 1 to 25% are suspended materials, the rest being transported under dissolved form. The flushed material does not correspond exactly with the lithology of the aquifer: for the dissolved material, Mg is in excess compared to the Mg in the carbonates (exchange of cations Ca-Mg); for the suspended material, the clay minerals clearly out-weight the quartz (selection by different sizes and forms).

Alpine karsts. Genesis of large subterranean networks. Examples : the Tennengebirge (Austria) - the Ile de Crémieu, the Chartreuse and the Vercors (France), PhD Thesis, 1993, Audra, Philippe

This work, based on the study of several underground alpine networks, aims to propose some milestone in the history of these karstic regions.

The first part of the work is made up of three regional studies.

The Tennengebirge mountains are a massif of the limestone High Alps in the region of Salzburg in Austria. A cone karst close to the base level developed in the Neogene. Streams from the Alps fed the karst, resulting in the huge horizontal networks of which the Eisriesenwelt provides evidence. During the successive phases of upthrust, the levels of karstification, whether on the surface or deeper down, settled into a tier pattern, thus descending in stages from the base level. From the Pliocene era onwards, thanks to an increase in potential, alpine shafts replace the horizontal networks. The formation of these shafts is more pronounced during glaciation. The study of the Cosa Nostra - Bergerhöhle system developing 30 km of conduits on a gradient reaching almost 1 500 m provides a fairly full view of the karstification of this massif. It includes the horizontal levels developed in the Miocene and the Plio-Pleistocene, joined together by vertical sections. The most noteworthy features of the Tennengebirge, as in the neighboring massifs, lie first and foremost in the extreme thickness of the limestone which has recorded and immunized the differents steps of karstification. Secondly, the size of the networks can be, for the most part, accounted for by the contribution of allogenous waters from the streams of the Neogene and the glaciers of the Pleistocene. Generally sudden and unexpected, these flows of water engendered heavy loads (up to 600 m), simultaneously flooding several levels. To a lesser extent, the situation is similar today.

The Ile de Cremieu is a low limestone plateau on the western edge of the Jura. Due to its location in the foothills, the lobes of the Rhône glacier have covered it up, obliterating the surface karst. However, widespread evidence of anteglacial morphologies remains : paleokarst, cone karst, polygenic surface. Because of glacial plugging, access to the underground karst is limited. The main cavity is the cave of La Balme. Its initial development dates back to an early period. The morphological study has permitted the identification of several phases which go back to the Pleistocene and which are related to the Rhône glacier. The latter brought about modifications in the base level by supplying its merging waters as well as moraine material. These variations in the base level shaped the drainage structure. The underground glacial polishes are one of the noteworthy aspects recorded.

The massives of the Moucherotte and dent de Crolles belong to the northern French Prealps. They conceal large networks, respectively the Vallier cave and the Dent de Crolles. They were formed in the early Pliocene after the final orogenic phase and are in the form of horizontal conduits. The upthrust, which brought about the embanking of the Isère valley, left them in a perched position by taking away the basin which fed them. They were later, however, able to take advantage of waters from the Isère glacier during a part of the Pleistocene. The Vallier cave contains particularly glacio-karstic sediments of the lower Pleistocene, representing unique evidence of glaciation during this period. The vertical networks were put in place at the end of the Pliocene with the increase in karstification potential ; they underwent changes in the Pleistocene due to the effect of autochton and allogenous glaciers.

The second part of the work deals in general with the various forms and processes of karstification, sometimes going beyond the Alps. The study of cave deposits is a privileged tool in the understanding and reconstruction not only of the history of the networks but also the regional environment. The dating of speleothems by the U / Th method has very ofen given an age of over 350 000 years. The age of the networks is confirmed by the use of paleomagnetism which has yielded evidence of speleothems and glacio-karstic sediments anterior to 780 000 years. Anisotropic measurements of magnetic susceptibility have been used to distinguish the putting into place of glacio-karstic deposits by decantation.

Measurements of calcite rates lead to a typology of sediments based on their nature and carbonate content (rehandled weathered rocks, fluvial sands, carbonated varves, decantation clays). Granulometry confirms this differenciation by supplying precise details of transport and sedimentation modes : suspension and abrupt precipitation of clay, suspension and slow decantation of carbonated varves, suspension and rolling together with a variable sorting of sand and gravel. Mineralogical analyses oppose two types of detrital deposits. On the one hand, the rehandling of antequaternary weathered rocks extracted by the karst as a result of scouring during environmental destabilization and on the other hand, sediments characteristic of the ice age of the Pleistocene. The latter are not highly developed and their arrival in the karst is always later. Examination of heavy minerals, the morphoscopy of quartz grains and study of micromorphologies on thin blades provide precise details of conditions of evolution. The use of these methods of investigation allows for an accurate definition of the features of the evolution of the differents types of fillings, particularly speleothems, rehandled weathered rocks as well as carbonated varves. This wealth and complexity are emphasized by a detailed study of the sedimentary sequences of the Vallier cave and of the Bergerhöhle.
Speleogenesis is approached last of all in the light of above study. Emphasis is placed on the major part played by corrosion in the temporarily phreatic zone and on its many consequences (multi-level concept, simultaneous evolution of levels, origin of deep waterlogged karsts…).
Varia tions in the base level have induced karstification in contexts in which the potential was weak. These were followed by periods of increased potential to which were added the effects of glaciation. Perched horizontal levels belong to the first stages which ended in the early Pliocene, whereas alpine shafts developed in the second context. The role of structure and the parameters governing the shape of conduits (pits, meanders, canyons) are also dealt with. The different parts of the karst are borne in mind when dealing with the strength of karstic erosion during the ice age. It notably appears that it is weak on the crests and more or less non-existent in the deep parts of the karst which are liable to flooding. Finally, a preliminary analysis of an observation of neotectonic traces is presented.


Convolution a debit variable a partir des reponses de tracages artificiels; application a un systeme karstique (Causse de Gramat, Lot, France): Convolution in time-dependent system from artificial tra, 1995, Dzikowski M, Delay F, Sauty Jp, Crampon N, De Marsily G,
ResumeLa realisation de tracages artificiels dans des conditions hydrodynamiques differentes sur le systeme karstique de I'Ouysse (Causse de Gamat, France) ainsi que de mesures physicochimiques portant entre autres sur les chlorures, nitrates et matieres en suspension ont permis d'exploiter les possibilites de l'analyse des systemes-tracages dependant du temps. Pour des tracages artificiels realises a des periodes hydrologiques differentes (basses-eaux et hauteseaux), les relations entre les reponses impulsionnelles a l'injection instantanee de traceur et les debits d'ecoulement variables associes sont mises en evidence sur un systeme a deux entrees (pertes de Themines et Theminettes) et une sortie (gouffre de Besaces). Ces relations etablissent une independance entre l'espace occupe par le traceur au cours de son transfert et les conditions hydrodynamiques dans la gamme de debits interessant chaque tracage. Des operations de convolutions d'entrees en chlorures, nitrates et matieres en suspension, basses sur l'hypothese d'un systeme a volume constant dependant du temps ont donc pu etre realisees. Les resultats sont compares au mesures experimentales au point de sortie (Besaces).AbstractArtificial tracer tests conducted under different hydrodynamic conditions on the karst system of Ouysse (Causse de Gramat, France) and chemical measurements have permitted the use of the time-dependent tracer test analysis. For artificial tracer experiments in different hydrologic periods (water rise and high flow), the relationships between the responses to an instantaneous injection are improved in a system defined by two inputs (losses of Themines and Theminettes). They show that the space occupied by the mass of tracer during its transfer can be considered as independent of the discharge according to the range of flow rate in which the tracer experiments have been conducted. Therefore, convolutions on chlorides, nitrates and suspended sediments are simulated under the hypothesis of a constant-volume and time-dependent system. The computed results are compared with the experimental data at the output (cave of Besaces)

Lanthanide-labeled clay: A new method for tracing sediment transport in karst, 1998, Mahler B. J. , Bennett P. C. , Zimmerman M. ,
Mobile sediment is a fundamental yet poorly characterized aspect of mass transport through karst aquifers. Here the development and field testing of an extremely sensitive particle tracer that may be used to characterize sediment transport in karst aquifers is described. The tracer consists of micron-size montmorillonite particles homoionized to the lanthanide form; after injection and retrieval from a ground water system, the lanthanide ions are chemically stripped from the clay and quantified by high performance liquid chromatography, The tracer meets the following desired criteria: low detection limit; a number of differentiable signatures; inexpensive production and quantification using standard methods; no environmental risks; and hydrodynamic properties similar to the in situ sediment it is designed to trace. The tracer was tested in laboratory batch experiments and field tested in both surface water and ground water systems. In surface water, arrival times of the tracer were similar to those of a conservative water tracer, although a significant amount of material was lost due to settling. Two tracer tests were undertaken in a karst aquifer under different flow conditions. Under normal flow conditions, the time of arrival and peak concentration of the tracer were similar to or preceded that of a conservative water tracer. Under low flow conditions, the particle tracer was not detected, suggesting that in low flow the sediment settles out of suspension and goes into storage

Processes controlling colloid composition in a fractured and karstic aquifer in eastern Tennessee, USA, 1998, Mccarthy J. F. , Shevenell L. ,
Groundwater was sampled from a number of wells along recharge pathways between fractured shale and karstic formations to evaluate the chemical and hydrologic mechanisms controlling the nature and abundance of groundwater colloids. The colloids recovered using low flow rate purging and sampling exhibited a composition and abundance consistent with lithology, flow paths, and effects of hydrology and aqueous chemistry on colloid mobilization and stability. In general, the larger-size colloids and Ca-containing colloids were more abundant in the karstic lithologies, while Na-containing colloids were more important in the shales. The composition of the colloids reflected recharge pathways from the fractured shale and dolomite formations on the ridges into the limestone in the valley floor. The Mg-colloids in the limestone reflect the possible contributions from the dolomite, while the Na, K, and Si reflect possible contributions from the shale, However, it was not possible to use the colloid composition as a signature to demonstrate colloid transport from one lithology to another. Mixing of recharge water from the shale with groundwater within the limestone formation and precipitation/dissolution reactions could account for the colloids present in the limestone without invoking transport of specific shale-derived colloids into the limestone formation. The abundance of colloids in groundwater appears to be controlled by both chemical factors affecting colloid stability, as well as physical factors related to hydrology (storm-driven recharge and water velocities). In general, colloids were more abundant in wells with low ionic strength, such as shallow wells in water table aquifers near sources of recharge at the top of the ridges, Increases in cation concentrations due to dissolution reactions along Bow paths were associated with decreases in colloid abundance. However, in spite of elevated ionic strength, colloid concentrations tended to be unexpectedly high in karstic wells that were completed in cavities or water-bearing fractures. The higher levels of colloids appear to be related to storm-driven changes in chemistry or flow rates that causes resuspension of colloids settled within cavities and fractures. Published by Elsevier Science B.V

DETRITAL ORIGIN OF A SEDIMENTARY FILL, LECHUGUILLA CAVE, GUADALUPE MOUNTAINS, NEW MEXICO, 2000, Foos Am, Sasowsky Id, Larock Ej, Kambesis Pn,
Lechuguilla Cave is a hypogene cave formed by oxidation of ascending hydrogen sulfide from the Delaware Basin. A unique sediment deposit with characteristics suggesting derivation from the land surface, some 285 m above, was investigated. At this location, the observed stratigraphy (oldest to youngest) was: bedrock floor (limestone), cave clouds (secondary calcite), calcite-cemented silstone, finely laminated clay, and calcite rafts. Grain-size analysis indicates that the laminated clay deposits are composed of 59-82% clay-size minerals. The major minerals of the clay were determined by X-ray diffraction analysis and consist of interstratified illite-smectite, kaolinite, illite, goethite, and quartz. Scanning electron microscopy observations show that most of the clay deposit is composed of densely packed irregular-shaped clay-size flakes. One sample from the top of the deposit was detrital, containing well-rounded, silt-size particles. Surface soils are probably the source of the clay minerals. The small amount of sand- and silt-size particles suggests that detrital particles were transported in suspension. The lack of endellite and alunite is evidence that the clays were emplaced after the sulfuric-acid dissolution stage of cave formation. Fossil evidence also suggests a previously existing link to the surface

Function feeding groups of macroinvertebrates in the Reka river (Slovenia), 2000, Pipan, Tanja

This ecological study deals with the structure of the fauna in a Karst river, classified into different feeding. From the source to the swallow hole the proportion of suspension feeders, filterer-collectors and shredders diminished, but the proportion of deposit feeders and grazers increased. The proportion of predators was roughly the same at all sampling sites. Biological research showed that in the Reka river optimal food exchange with slightly increased trophic activity takes place, but it does not have a negative effect on the community structure of macroinvertebrates.


Mise en vidence du phnomne du renard : exemple des crues exceptionnelles des sources du Boulet-Blagour (Causse de Martel, Lot), 2001, Fabre Jeanpaul, Perrineau Alain
hydraulicians (dam construction) and ignored until now by hydrologists.

Water-upwelling pipes and soft-sediment-deformation structures in lower Pleistocene calcarenites (Salento, southern Italy), 2001, Massari F. , Ghibaudo G. , D'alessandro A. , Davaud E. ,
A thin sedimentary blanket, consisting mostly of subtidal, unconformity-bounded calcarenite units, was deposited in the small Novoli graben (Apulian foreland, southern Italy) in Pliocene-Pleistocene time. In a limited part of the study area the lower Pleistocene 'Calcarenite di Gravina,' forming the thicker part of this blanket, is crossed by continuous to discontinuous cylindrical pipes as much as 12 m high, most commonly consisting of stacked concave- upward laminae, locally grading upward into soft-sediment-deformation features and large dishes. The evidence favors an origin linked to upwelling of overpressured groundwater from a large karstic reservoir hosted in the Mesozoic carbonate rocks; the reservoir periodically developed a relatively high hydrostatic head due to Tertiary to Pleistocene cover acting as an aquitard or aquiclude. As a result, submarine springs were generated, the activity of which was primarily controlled by relative sea-level fluctuations. It is suggested that the pipes were located in those points where the hydrostatic pressure was sufficient to fluidize the overlying sediment and could be released without notably affecting the surrounding sediments. Some pipes cross calcarenitic infills of karstic sinkholes developed in the underlying units, whereas others follow the course of vertical to high-angle extensional synsedimentary tectonic fractures generated when the calcarenites were still in an unconsolidated to semiconsolidated state. The former relationships suggest that vertical routes of water upwelling during highstand of base level commonly coincided with axes of vadose solution during base-level lowstand; the latter suggest that opening of fractures enhanced the connection of the deep aquifer with the surface, hence intensifying water upwelling. We think that fluidization along the fractures was not hindered by the partially coherent state, and that pipes with a cylindrical geometry could form in spite of the planarity of the fractures. The formation of the pipes and their internal structure of stacked concave-upward laminae is thought to be consistent with a process of fluidization due to through-flowing waters. We believe that essential in this process is the role of upward-migrating transient water-filled cavities, akin to the voidage waves (Hassett's [1961a, 1961b] parvoids) experimentally reproduced by several authors in liquid fluidized beds, and regarded as true instability phenomena of a fluidized suspension occurring above minimum fluidization velocity. It is suggested that the process is akin to the production of the dish structure. It consists of the filling of transient, upward-migrating, water-filled cavities through steady fallout of particles from the cavity roof, their redeposition in a more consolidated state, and subsidence of the roof due to water seepage upward from the cavity. The process was accompanied by segregation of grains according to their size and density, as well by elutriation of finest particles, and led to a new pattern of sediment texture, packing, and fabric with respect to the surrounding calcarenites

Contaminant transport in karst aquifers., 2001, Vesper D. J. , Loop C. M. , White W. B.
Contaminants are easily injected into karst aquifers through sinking streams, sinkholes, or through open fractures and shafts in the carbonate rock. Transport of the contaminants through the aquifer is by a variety of mechanisms depending on the physical and chemical properties of the contaminant. Contaminants consist of (1) water soluble compounds, both organic and inorganic, (2) slightly soluble organic compounds, less dense than water (LNAPLs), (3) slightly soluble organic compounds, more dense than water (DNAPLs), (4) pathogens, (5) metals, and (6) trash. Water soluble compounds (e.g. nitrates, cyanides, carboxylic acids, phenols) move with the water. But rather than forming a plume spreading from the input point, the contaminated water forms linear stringers migrating down the conduit system toward the discharge point. LNAPLs (e.g. petroleum hydrocarbons) float on the water table and can migrate down the water table gradient to cave streams where they tend to pond behind obstructions. DNAPLs (e.g. chlorinated hydrocarbons), in contrast, sink to the bottom of the aquifer. In the conduit system, DNAPLs pond in low spots at the bottom of the conduit and infiltrate sediment piles. Transport of both LNAPL and DNAPL is dependent on storm flow which can force LNAPL through the system as plug flow and can move DNAPLs by mobilizing the sediment piles. Pathogens (viruses, bacteria, parasites) are transported through the karstic drainage system because of the absence of filtration and retain their activity for long distances. Metals (e.g. chromium, nickel, cadmium, mercury, and lead) tend to precipitate as hydroxides and carbonates in the neutral pH, carbonate rich water of the karst aquifer. Metal transport is mainly as particulates and as metal adsorbed onto small particulates such as clays and colloids. Metal transport is also episodic. Metals migrate down the flow path under flow conditions that take small particulates into suspension. Trash is carried into karst aquifers through sinkholes and sinking streams. It is, in effect, a form of clastic sediment, and can be carried deep into the conduit system where it can act as a source term for other contaminants leached from the trash.

Contaminant transport in karst aquifers, 2003, Vesper D. J. , Loop C. M. , White W. B.

Contaminants are easily injected into karst aquifers through sinking streams, sinkholes, or through open fractures and shafts in the carbonate rock. Transport of the contaminants through the aquifer is by a variety of mechanisms depending on the physical and chemical properties of the contaminant. Contaminants consist of (1) water soluble compounds, both organic and inorganic, (2) slightly soluble organic compounds, less dense than water (LNAPLs), (3) slightly soluble organic compounds, more dense than water (DNAPLs), (4) pathogens, (5) metals, and (6) trash. Water soluble compounds (e.g. nitrates, cyanides, carboxylic acids, phenols) move with the water. But rather than forming a plume spreading from the input point, the contaminated water forms linear stringers migrating down the conduit system toward the discharge point. LNAPLs (e.g. petroleum hydrocarbons) float on the water table and can migrate down the water table gradient to cave streams where they tend to pond behind obstructions. DNAPLs (e.g. chlorinated hydrocarbons), in contrast, sink to the bottom of the aquifer. In the conduit system, DNAPLs pond in low spots at the bottom of the conduit and infiltrate sediment piles. Transport of both LNAPL and DNAPL is dependent on storm flow which can force LNAPL through the system as plug flow and can move DNAPLs by mobilizing the sediment piles. Pathogens (viruses, bacteria, parasites) are transported through the karstic drainage system because of the absence of filtration and retain their activity for long distances. Metals (e.g. chromium, nickel, cadmium, mercury, and lead) tend to precipitate as hydroxides and carbonates in the neutral pH, carbonate rich water of the karst aquifer. Metal transport is mainly as particulates and as metal adsorbed onto small particulates such as clays and colloids. Metal transport is also episodic. Metals migrate down the flow path under flow conditions that take small particulates into suspension. Trash is carried into karst aquifers through sinkholes and sinking streams. It is, in effect, a form of clastic sediment, and can be carried deep into the conduit system where it can act as a source term for other contaminants leached from the trash


Transfer of bacteria-contaminated particles in a karst aquifer: evolution of contaminated materials from a sinkhole to a spring, 2003, Dussartbaptista L, Massei N, Dupont Jp, Jouenne T,
The transport of particle-associated bacteria during rain events in karst waters has been investigated. In this aim, we studied the correlations between water turbidity and enumerations of sessile (attached) and planktonic (non-attached) bacteria. We monitored physicochemical, i.e. turbidity, electrical conductivity, size and nature of the transported particles, and bacteriological properties of waters since their infiltration on a karst plateau to their discharge at a karstic spring. Results showed a decrease of the concentration of sessile bacteria at the sinkhole for high turbidities. This phenomenon might be explained by the arrival of lower contaminated material. On the other hand, the amount of sessile bacteria at the spring was not influenced by the turbidity values. These data demonstrated that slightly contaminated larger particles were not recovered, whereas small-size particles, which exhibited a higher bacterial contamination, were directly transferred (i.e. not affected by intra-karstic deposition) through the aquifer. Our study highlighted some significant differences between the bacteriological time series at the sinkhole and at the spring, which characterizes the storage/resuspension function of the considered karst system. Moreover, we show a decrease of the concentration of planktonic bacteria after transport through the system whereas no reduction of the sessile population occur-red. The present data confirm that turbidity does not constitute a good indicator for bacterial contamination: if high turbidity corresponds to high bacterial contamination, low turbidity does not systematically exclude a risk of contamination by sessile organisms. (C) 2003 Elsevier B.V. All rights reserved

Assessment of direct transfer and resuspension of particles during turbid floods at a karstic spring, 2003, Massei N. , Wang H. Q. , Dupont J. P. , Rodet J. , Laignel B. ,
Turbid water can be the source of important sanitary problems in karstic regions. It is the case of the Pays de Caux, in Haute Normandie, where the main resource in drinking water is provided by the chalk aquifer. In the case of the typical binary karst of the Pays de Caux, turbidity results from the input in sinkholes of turbid surface water induced by erosion on the plateaus. At some spring tappings, water may be very turbid in period of intense rainfall. The turbidity observed at a karstic spring is a complex signal which contains a part of direct transfer and a part of resuspension of the particles being transported. The aim of this study is turbidigraph separation, which would permit to distinguish the direct transfer and resuspension components of the turbidigraph. These two components are separated by comparing the elementary surface storm-derived water fluxes and elementary turbidity signals at the spring. The procedure takes place in three phases: (i) spring hydrograph separation by means of a two components mixing model (surface water and karstic groundwater) using specific electrical conductivity, (ii) decomposition of storm-derived water flux and turbidity thanks to the second-derivative method, (iii) comparison of the transfer times (approximate tomodal times) of the elementary turbidity and surface water flux signals, respectively. The mass corresponding to direct transfer, computed after signal decomposition, is then used to re-calculate a particle recovery rate, which passes so from 514 to 373%. Relations between particle flux and hydrodynamics show that resuspension can be either the fact of the dynamics of the introduction system, or that of the chalk karstic aquifer in general (case of resuspension not associated to surface water flux). In this sense, evolution of particle flux (and consequently of turbidity) can be also a marker of the karst structure. (C) 2003 Elsevier Science B.V. All rights reserved

Escherichia coli survival in mantled karst springs and streams, northwest Arkansas Ozarks, USA, 2005, Davis Rk, Hamilton S, Van Brahana J,
Recent studies indicate fecal coliform bacterial concentrations, including Escherichia coli (E. coli), characteristically vary by several orders of magnitude, depending on the hydrology of storm recharge and discharge. E. coli concentrations in spring water increase rapidly during the rising limb of a storm hydrograph, peak prior to or coincident with the peak of the storm pulse, and decline rapidly, well before the recession of the storm hydrograph. This suggests E. coli are associated with resuspension of sediment during the onset of turbulent flow, and indicates viable bacteria reside within the spring and stream sediments. E. coli inoculated chambers were placed in spring and stream environments within the mantled karst of northwest Arkansas to assess long term (> 75 days) E. coli viability. During the 75-day study, a 4-log die-off of E. coli was observed for chambers placed in the Illinois River, and a 5-log die-off for chambers placed in Copperhead Spring. Extrapolation of the regression line for each environment indicates E. coli concentration would reach 1 most probable number (MPN)/100 g sediment at Copperhead Spring in about 105 days, and about 135 days in the Illinois River, based on a starting inoculation of 2.5 x 107 MPN E. coli/100 g of sediment. These in situ observations indicate it is possible for E. coli to survive in these environments for at least four months with no fresh external inputs

The Genesis of the Hope Downs Iron Ore Deposit, Hamersley Province, Western Australia, 2006, Lascelles Desmond F. ,
The banded iron formation (BIF)-hosted Hope Downs high-grade hematite ore deposits are situated within the Marra Mamba Iron Formation with subsidiary deposits in the Brockman Iron Formation of the Archean to Proterozoic Hamersley Group of Western Australia. The main orebody extends to 260 m below the surface and is unusually rich in martite (pseudomorphous hematite after magnetite) and poor in limonite and goethite compared to other ore deposits of the Marra Mamba Iron Formation. The high-grade hematite ore is mainly within the Newman Member but also occurs in parts of the Nammuldi Member together with low-grade limonitic ore that becomes high grade after calcining. Karst erosion of the overlying Wittenoom Formation has produced steep-sided buried valleys adjacent to the in situ orebodies that contain thick deposits (<160 m) of goethitic and sideritic sediments, including remnants of Robe Pisolite Formation, bedded siderite, hematite gravels, red ochreous detrital material, and enriched scree deposits that are additional sources of ore. The ore consists of low phosphorous martite-limonite-goethite derived from chert-free BIF by supergene weathering. No evidence of the complete carbonate replacement of chert has been found at Hope Downs nor were any traces of preexisting chert bands seen in the ore, despite the abundance of chert bands in BIF elsewhere. A variety of textures and composition shown by cherty BIF adjacent to the orebodies is described from which the origin of the chert-free BIF is inferred, including sedimentary structures consistent with density-current deposition. A model is presented for the origin of the host iron formation and the ore deposits, in which density currents transported reworked iron silicates and hydroxides in colloidal suspension onto an unstable sea floor. The amorphous silica produced during diagenesis of Al-poor iron silicates formed the characteristic chert bands of BIF but some of the hydrous amorphous silica was lost prior to lithification to form chert-free BIF. Weathering of the chert-free BIF produced the high-grade hematite ore that is exposed today

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