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Enviroscan Ukrainian Institute of Speleology and Karstology


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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 Kluftkarren is (german.) see grike.?

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 indexes (Keyword) returned 36 results for the whole karstbase:
Showing 16 to 30 of 36
Groundwater vulnerability map of the Chrzanow karst-fissured Triassic aquifer (Poland), 2003,
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Witkowski A. J. , Rubin K. , Kowalczyk A. , Rozkowski A. , Wrobel J. ,
A map shows intrinsic vulnerability to pollution of the Chrzanow karst-fissured aquifer (273 km(2)) in the southern part of Poland. This aquifer is intensively drained by numerous intakes and Zn-Pb ore mines. A DRASTIC-type parametric system was applied for groundwater vulnerability evaluation. Vulnerability assessment is based on six factors (depth to groundwater table, lithology of the unsaturated zone, net recharge, hydraulic conductivity of the aquifer, groundwater flow velocity, aquifer thickness). For the final vulnerability map construction at the scale of 1:50,000, a combination of the aquifer simulation model (using MODFLOW) and a geographical information system was applied. Maps of the net recharge, hydraulic conductivity of the aquifer and groundwater flow velocity were derived by aquifer modelling. Based on the vulnerability index (21-182), six relative vulnerability classes were selected. Reliability of the map has been verified

Unraveling the Origin of Carbonate Platform Cyclothems in the Upper Triassic Durrenstein Formation (Dolomites, Italy), 2003,
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Preto Nereo, Hinnov Linda A. ,
Facies analysis of the Durrenstein Formation, central-eastern Dolomites, northern Italy, indicates that this unit was deposited on a carbonate ramp, as evidenced by the lack of a shelf break, slope facies, or a reef margin, together with the occurrence of a 'molechfor' biological association. Its deposition following the accumulation of rimmed carbonate platforms during the Ladinian and Early Carnian marks a major shift in growth mode of the Triassic shallow marine carbonates in the Dolomites. The Durrenstein Formation is characterized by a hierarchical cyclicity, with elements strongly suggestive of an allocyclic origin, including (a) subaerial exposure features directly above subtidal facies within meter-scale cyclothems, (b) purely subtidal carbonate cyclothems, (c) symmetric peritidal carbonate cyclothems, and (d) continuity of cyclothems of different orders through facies boundaries. The Durrenstein cyclothems are usually defined by transgressive and regressive successions, and so most of them probably originated from sea-level oscillations. Their allocyclic origin allows their use for high-resolution correlations over distances up to 30 km. A stratigraphic section in the Tre Cime di Lavaredo area, encompassing the upper part of the Durrenstein Formation and the lower part of the overlying Raibl Formation (Upper Carnian) was studied using time-frequency analysis. A strong Milankovitch signal appeared when interference arising from a variable sedimentation rate was estimated and removed by tuning the short precession line in a spectrogram. All of the principal periodicities related to the precession index and eccentricity, calculated for 220 Ma, are present: P1 (21.9 ky); P2 (17.8 ky); E1 (400 ky), E2 (95 ky), and E3 (125 ky), along with a peak at a frequency double that of the precession, which is a predicted feature of orbitally forced insolation at the equator. Components possibly related to Earth's obliquity at ca. 35 ky and ca. 46 ky are present as well. The recovery of Milankovitch periodicities allows reconstruction of a high-resolution timescale that is in good agreement with published durations of the Carnian based on radiometric ages. The recognition of a Milankovitch signal in the Durrenstein and lower Raibl formations, as well as in other Mesozoic carbonate platforms, strongly supports a deterministic and predictable--rather than stochastic--control on the formation of carbonate platforms. Carbonate platforms might thus be used in the future for the construction of an astronomical time scale for the Mesozoic

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

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

Geochemical exploration for gold in Jamaica: a comparison of stream sediment and soil surveys, 2004,
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Garrett Rg, Lalor Gc, Vutchkov M,
The geology of Jamaica is reviewed with reference to gold. Two geochemical surveys, one employing stream sediments for mineral exploration in selected regions of Jamaica considered a priori to have greater mineral potential, and the other an island-wide low-density soil survey to meet agro-environmental objectives, were undertaken in 1986 and 1988, respectively. The paper presents an interpretation of the previously unpublished soil data for gold, and undertakes a comparison of the two surveys in terms of their effectiveness for gold exploration. The stream sediment survey (1 site per 1 km2) led to the discovery of three new gold occurrences, one of which became a producing mine in 2001, and the recognition of two previously known auriferous districts. The low-density soil survey (1 site per 64 km2) identified the host rocks of three of these auriferous districts as having gold potential, including those of the producing mine, demonstrating its value as a broad-scale regional mineral reconnaissance tool. Geochemical studies of gold in Jamaica are complicated by the presence of transported palaeo-anomalies, related to Miocene ash-falls, in terra rossa soils in karst terrain. The Fe/Na ratio is an index of soil maturity and increases over two-and-a-half orders of magnitude with increasing soil age and mature. The plotting of Au versus the Fe/Na ratio in soils offers a simple procedure for identifying samples most likely to be related to gold occurrences in bedrock, i.e. high Au and low Fe/Na ratio. It is concluded that in the specific instance of Jamaica's high relief terrain and the apparent limitation of gold occurrences to the Cretaceous Inliers and Eocene Wagwater Trough underlying those high relief areas, stream sediment sampling is the most effective mineral exploration tool

South China karst aquifer storm-scale hydrochemistry, 2004,
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Liu Z. H. , Groves C. , Yuan D. X. , Meiman J. ,
The peak cluster and peak forest karst regions of Southeast Asia form one of the earth's most extensive karst regions. Although there exists a rich, descriptive tradition of geomorphic work performed there, little quantitative study has been made of carbonate hydrochemistry and related aquifer/landscape behavior and evolution. In this paper, high-resolution measurements of ground water carbonate chemistry and flow were made and analyzed at two adjacent locations within the subtropical peak cluster karst of the Guilin Karst Experimental Site in Guangxi Province, China. While waters from a large, perennial spring represent the exit for the 2 km(2) catchment's conduit flow, a nearby well (within 5 m) measures water in the conduit-adjacent, fractured media. Results indicate that within peak cluster karst aquifer flow systems, spatially heterogeneous flow conditions can exist with respect to timing, magnitude, and, in some cases, direction of responses, as different controls can operate in the different flow system components. Stormscale chemical responses are controlled by dilution from rapid infiltration of rain water, CO2 gas sources and sinks, and water-carbonate rock interactions. At this particular location, there is also an influence from high pH recharge, apparently buffered by atmospheric limestone dust. An example of the varying controls on storm-scale responses within the flow system is that within the fractured medium, variations in the ground water calcite saturation index, a key parameter influencing rates of aquifer/landscape evolution, are small and controlled by CO 2 gas, while in the conduit they are more significant and dominated instead by dilution with rain water

Storm pulse chemographs of saturation index and carbon dioxide pressure: implications for shifting recharge sources during storm events in the karst aquifer at Fort Campbell, Kentucky/Tennessee, USA, 2004,
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Vesper D. J. , White W. B. ,
Continuous records of discharge, specific conductance, and temperature were collected through a series of storm pulses on two limestone springs at Fort Campbell, western Kentucky/Tennessee, USA. Water samples, collected at short time intervals across the same storm pulses, were analyzed for calcium, magnesium, bicarbonate, total organic carbon, and pH. Chemographs of calcium, calcite saturation index, and carbon dioxide partial pressure were superimposed on the storm hydrographs. Calcium concentration and specific conductance track together and dip to a minimum either coincident with the peak of the hydrograph or lag slightly behind it. The CO2 pressure continues to rise on the recession limb of the hydrograph and, as a result, the saturation index decreases on the recession limb of the hydrograph. These results are interpreted as being due to dispersed infiltration through CO2-rich soils lagging the arrival of quick-flow from sinkhole recharge in the transport of storm flow to the springs. Karst spring hydrographs reflect not only the changing mix of base flow and storm flow but also a shift in source of recharge water over the course of the storm

Hydrochemical variations during flood pulses in the south-west China peak cluster karst: impacts of CaCO3-H2O-CO2 interactions, 2004,
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Liu Z. H. , Groves C. , Yuan D. X. , Meiman J. , Jiang G. H. , He S. Y. , Li Q. A. ,
High-resolution measurements of rainfall, water level, pH, conductivity, temperature and carbonate chemistry parameters of groundwater at two adjacent locations within the peak cluster karst of the Guilin Karst Experimental Site in Guangxi Province, China, were made with different types of multiparameter sonde. The data were stored using data loggers recording with 2 min or 15 min resolution. Waters from a large, perennial spring represent the exit for the aquifer's conduit flow, and a nearby well measures water in the conduit-adjacent, fractured media. During flood pulses, the pH of the conduit flow water rises as the conductivity falls. In contrast, and at the same time, the pH of groundwater in the fractures drops, as conductivity rises. As Ca2 and HCO3- were the dominant (>90%) ions, we developed linear relationships (both r(2) > 0.91) between conductivity and those ions, respectively, and in turn calculated variations in the calcite saturation index (SIc) and CO2 partial pressure (PCO2) of water during flood pulses. Results indicate that the PCO2 of fracture water during flood periods is higher than that at lower flows, and its SIc is lower. Simultaneously, PCO2 of conduit water during the flood period is lower than that at lower flows, and its SIc also is lower. From these results we conclude that at least two key processes are controlling hydrochemical variations during flood periods: (i) dilution by precipitation and (ii) water-rock-gas interactions. To explain hydrochemical variations in the fracture water, the water-rock-gas interactions may be more important. For example, during flood periods, soil gas with high CO2 concentrations dissolves in water and enters the fracture system, the water, which in turn has become more highly undersaturated, dissolves more limestone, and the conductivity increases. Dilution of rainfall is more important in controlling hydrochemical variations of conduit water, because rainfall with higher pH (in this area apparently owing to interaction with limestone dust in the lower atmosphere) and low conductivity travels through the conduit system rapidly. These results illustrate that to understand the hydrochemical variations in karst systems, considering only water-rock interactions is not sufficient, and the variable effects of CO2 on the system should be evaluated. Consideration of water-rock-gas interactions is thus a must in understanding variations in karst hydrochemistry. Copyright (C) 2004 John Wiley Sons, Ltd

River backflooding into a karst resurgence (Loiret, France), 2004,
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Alberic P,
The group of springs located in the west part of the Val d'Orleans exemplifies a type of karstic emergence which has the particularity to get most of its recharge water from a single surface water source, which in this particular case is the River Loire. Hence the flow of this group of springs is known to fluctuate in a close relationship with the water level of the River Loire. Since the second half of the 1990s, the conduit of the upstream spring of the Loiret river (so-called Le Bouillon) has been periodically seen to be invaded by the turbid waters of a small surface tributary (Le Dhuy) flowing back from the confluence to the spring, which then functioned as a swallow-hole. Plotted in a Dhuy versus River Loire diagram, stages of backflooding days describe a domain limited by a curve of the form HDhuy = c e((aH Loire)). The exponential form of the relation corresponds to the increasing resistance of the emerging flow of the spring to the backflooding of the tributary waters, as the River Loire stages rise. The equation above was used to compute a daily backflow index enabling the effective reconstruction of all occurrences effectively counted during the regular period of observation of the spring. Extended to 1985, one can observe that the early 1990s do not appear as a favorable period to backflow events but some may have occurred during the years 1986 to 1989. The observation of rainfall intensity preceding backflooding shows that in a short time span there is no necessity to evoke intrinsic changes inside the Val d'Orleans basin to explain what might appear as a troublesome new phenomenon. In conclusion backflooding has probably existed for a long time and is simply under the control of local heavy rainfall during low River Loire stages. (C) 2003 Elsevier B.V. All rights reserved

Floating Rafts of Calcite Crystals in Cave Pools, Central Texas, U.S.A.: Crystal Habit vs. Saturation State, 2004,
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Taylor Penny M. , Chafetz Henry S. ,
Calcite precipitation at the air-water interface in cave pools in central Texas (U.S.A) produces floating rafts of interconnected, low-Mg calcite crystals with individual crystal habits that range from equant (length to width = 1:1) to prismatic (4:1). Saturation state for the waters ranges from -0.19 to .35 (SIc = log IAP/K). Equant crystals precipitate from waters with a lower saturation index (SIc) and form rafts with a fused fabric whereas prismatic crystals precipitate from higher-SIc waters and form rafts with an interlaced fabric. The pools contain low-magnesium (molal Mg/Ca < 0.6), calcium-bicarbonate, and calcium-bicarbonate-nitrate type waters with temperatures that range from 13.8{degrees}C to 20.7{degrees}C and pH readings from 6.7 to 8.4. Equant euhedral crystals precipitate from water with saturation states close to equilibrium. Visible defects in the equant crystals include incomplete edges between faces and nearly circular (mean diameter 9 {micro}m) to angular holes in faces. The holes apparently result from crystallite growth around foreign objects on the crystal surface such as gas bubbles. Prismatic crystals precipitate from supersaturated water. Faces of these subhedral crystals are smaller in area than the faces of the equant crystals. No intrafacial circular holes are seen, but trigonal intercrystallite pores are common in the prismatic crystals. The variety in crystal habits, from equant to prismatic, is due to preferential growth along one crystallographic axis. Thus, in these cave pools crystal habit is related to the saturation state of the water

Intrinsic vulnerability assessment of the south-eastern Murge (Apulia, southern Italy), 2004,
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Marsico A. , Giuliano G. , Pennetta L. , Vurro M. ,
Maps of areas with different vulnerability degrees are an integral part of environmental protection and management policies. It is difficult to assess the intrinsic vulnerability of karst areas since the stage and type of karst structure development and its related underground discharge behaviour are not easy to determine. Therefore, some improvements, which take into account dolines, eaves and superficial lineament arrangement, have been integrated into the SIN-TACS R5 method and applied to a karst area of the southeastern Murge (Apulia, southern Italy). The proposed approach integrates the SINTACS model giving more weight to morphological and structural data; in particular the following parameters have been modified: depth to groundwater, effective infiltration action, unsaturated zone attenuation capacity and soil/overburden attenuation capacity. Effective hydro-geological and impacting situations are also arranged using superficial lineaments and karst density. In order to verify the reliability of the modified procedure, a comparison is made with the original SINTACS R5 index evaluated in the same area. The results of both SINTACS index maps are compared with karst and structural features identified in the area and with groundwater nitrate concentrations recorded in wells. The best fitting SINTACS map is then overlaid by the layout of potential pollution centres providing a complete map of the pollution risk in the area

Lithuanian karst region rivers' water ecology: hydrochemical and hydrobiological evaluation, 2004,
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Tumas R. ,
The Lithuanian karst region covers about 1000 km(3) in the northern part of the country. This is the most vulnerable area from a pollution point of view. The structure of the total dissolved solids (TDS) shows that the flow of rivers in the karst region is from hydraulically interconnected aquifers. For the last decade (1991-2000) TDS has varied considerably, from 529 to 732 mg/l. The predominant sources of nitrogen and phosphorus within the headwaters of the monitored rivers were diffuse and agricultural in nature. Downstream from the towns nitrogen and especially phosphorus showed both diffuse and point source signals. Contributions of point sources to the stream pollution by nutrients prevail. The time series of monthly dissolved oxygen (O-2) in the main karst region river - the Musa - shows the existence of multiplicative seasonality. The trend cycle (1991-1999) shows low levels of dissolved oxygen in 1991-1993, with a similar fluctuation in 1994, 1995 and 1996 (due to point pollution from the town of Siauliai) and a gradually improving situation since 1997. The general multiplicative trend of dissolved oxygen in the lower reaches of the Musa river (near the border with Latvia) is decreasing (within the accuracy limits). The abundance and species of zoo benthos are suitable criteria (biotic index - 131) for evaluation of a river's biological water quality. Zoo benthos demonstrates tolerances that vary among species, the oxygen regime and the pollution with nitrogen. The best living conditions for invertebrates are in the riverhead of the karst region rivers - 131 = 5.62-6.74 (1991-1999), where pollution with nutrients is caused mostly by agricultural activity. Rare and asynchronous data of biological water quality shows up tendencies that invertebrates prefer less contaminated reaches of rivers

Stable isotope (H-2, O-18 and Sr-87/Sr-86) and hydrochemistry monitoring for groundwater hydrodynamics analysis in a karst aquifer (Gran Sasso, Central Italy), 2005,
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Barbieri M, Boschetti T, Petitta M, Tallini M,
This paper deals with chemical and isotope analyses of 21 springs, which were monitored 3 times in the course of 2001; the monitoring program was focused on the groundwater of the Gran Sasso carbonate karst aquifer (Central Italy), typical of the mountainous Mediterranean area. Based on the hydrogeological setting of the study area, 6 groups of springs with different groundwater circulation patterns were distinguished. The hydrogeochemistry of their main components provided additional information about groundwater flowpaths, confirming the proposed classification. The spatial distribution of their ion concentrations validated the assumptions underlying the hydrogeological conceptual model, showing diverging groundwater flowpaths from the core to the boundaries of the aquifer. Geochemical modelling and saturation index computation elucidated water-carbonate rock interaction, contribution by alluvial aquifers at the karst aquifer boundaries, as well as impacts of human activities. The analysis of O-18/O-16 and H-2/H values and their spatial distribution in the aquifer substantiated the hydrogeology-based classification of 6 groups of springs, making it possible to trace back groundwater recharge areas based on mean isotope elevations; the latter were calculated by using two rain monitoring stations. Sr-87/Sr-86 analyses showed seasonal changes in many springs: in winter-spring, the changes are due to inflow of new recharge water, infiltrating into younger rocks and thus increasing (87)sr/Sr-86 values; in summer-autumn, when there is no recharge and spring discharge declines, changes are due to base flow groundwater circulating in more ancient rocks, with a subsequent drop in Sr-87/Sr-86 values. The results of this study stress the contribution that spatio-temporal isotope monitoring can give to the definition of groundwater flowpaths and hydrodynamics in fissured and karst aquifers, taking into account their hydrogeological and hydrogeochemical setting. (c) 2005 Elsevier Ltd. All rights reserved

Speleothem organic matter content imaging. The use of a Fluorescence Index to characterise the maximum emission wavelength, 2005,
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Perrette Y. , Delannoy J. J. , Desmet M. , Lignier V. , Destombes J. L. ,
The study of palacoenvironments, especially pedologic and biologic environments, is fundamental to a complete understanding of continental climate changes. Many types of sediment contain organic molecules (OM) that were trapped during the depositional process, with the quantity and the nature of these organic molecules being strongly influenced by climate and other local factors. The quantity of organic matter in sediment can be measured by fluorescence intensity, but its nature is more difficult to determine. For this research, the organic molecules in stalagmites were analysed using emission fluorescence spectroscopy. The analysis of carbonated karst sediments was complemented by studies of clay, soil and seepage water samples. The main objective of this paper is to describe a method for the continuous imaging of the spectroscopic features of stalagmite organic molecules. Continuous imaging provides a means of circumventing the nonlinearity, both in space (of the sediment) and in time (of the sedimentation process), of the trapping of organic matter. This methodological report presents a protocol for calculating a Fluorescence Index (FI) that can be used in palaeoenvironmental studies of sediment. A similar approach to that used for determining E4/E6 ratios was used to determine the ratio of the fluorescence intensities of a sample at 514 nm and at 456 nm. This Fluorescence Index is strongly correlated to the wavelength of the maximum intensity of the organic matter spectrum. Due to the relatively stable chemical environment of calcite growth, changes in the Fluorescence Index can be interpreted as being due to changes in the nature of the organic molecules rather than to pH or quenching effects. As an illustration of how this index can be used, we present some examples of fluorescence indices for speleothem samples that show short-term and long-term environmental changes. To allow fuller palaeoenvironmental interpretations to be made, fluorescence indices need to be calibrated to environments and samples need to be dated. (C) 2004 Elsevier B.V. All rights reserved

A Disturbance Index for Karst Environments, 2005,
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Van Beynen Philip, Townsend Kaya,

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