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Author Cardenal, J.; Benavente, J.; Cruz-Sanjulián, J.J. doi  openurl
  Title Chemical evolution of groundwater in Triassic gypsum-bearing carbonate aquifers (Las Alpujarras, southern Spain) Type Journal Article
  Year 1994 Publication Journal of Hydrology Abbreviated Journal  
  Volume 161 Issue 1 Pages 3-30  
  Keywords (up)  
  Abstract A hydrochemical study employing modelling techniques, was carried out using samples taken at 65 points (springs and wells) in Triassic carbonate aquifers (Lújar-Gádor Unit, Alpujárride Complex, Betic Cordillera). These aquifers are made up of limestones and dolomites with some gypsum scattered or interbedded. Though the area is semi-arid, recharge is relatively high because of their mountainous nature. The carbonate rocks contain dense microfissuration; the groundwater flow regime is predominantly diffuse. The karstic forms are in general poorly developed. Two main hydrochemical processes have been identified in these aquifers. One is incongruent dissolution of dolomite that determines the chemical composition of the less mineralised water. The other is dedolomitisation (dolomite dissolution together with calcite precipitation caused by dissolution of gypsum), which becomes predominant when the flow encounters interbedded gypsum. This reaction is also frequently associated with low temperature thermalism, and can play a part in more intense local karstification (cavities, sinkholes, high transmisivity in wells) observed in the sectors of these aquifers where gypsum is more abundant. A reaction path model has been used to simulate the geochemical processes through a hypothetical aquifer (with similar lithology to the Alpujárride carbonate aquifers). Successive stages of evolution through the carbonate sequence, represented by different saturation states with respect to calcite, dolomite gypsum and CO2, have been modelled and then compared with the field data.  
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  ISSN 0022-1694 ISBN Medium  
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  Notes Approved no  
  Call Number THL @ christoph.kuells @ Cardenal1994 Serial 18  
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Author Daniele, L.; Vallejos, Á.; Corbella, M.; Molina, L.; Pulido-Bosch, A. url  doi
openurl 
  Title Hydrogeochemistry and geochemical simulations to assess water–rock interactions in complex carbonate aquifers: The case of Aguadulce (SE Spain) Type Journal Article
  Year 2013 Publication Applied Geochemistry Abbreviated Journal  
  Volume 29 Issue Pages 43-54  
  Keywords (up)  
  Abstract The hydrogeological unit of Aguadulce (Campo de Dalías aquifers, SE Spain) has a complex geometry. This fact, together with a continuous rise in water demand due to intensive agriculture and tourism create problems for groundwater quantity and quality. In this paper classic geochemical tools managed by means of GIS software and geochemical simulations are combined to delineate, identify and locate the possible physicochemical processes acting in the Aguadulce groundwater. Two main aquifers can be distinguished: the carbonate or lower aquifer of Triassic age, and the calcodetritic or upper aquifer of Plio-Quaternary age. Groundwaters from the latter are more saline and, assuming all chlorinity originates from seawater intrusion, the seawater contribution to their composition would be up to 7%. Nevertheless the carbonate aquifer appears not to be homogeneous: it is compartmentalised into 4 zones where different processes explain the different groundwaters compositions. Zone 4 samples (E margin of the carbonate aquifer) resemble those of the Plio-Quaternary aquifer, where calcite precipitation, dolomite and gypsum dissolution and some cation exchange (water–rock interaction) together with seawater–freshwater mixing occur. In contrast, water–rock interaction predominates in zones 1 and 3 of the carbonate aquifer. Moreover, zone 2 samples, located between zones 1 and 3, are explained by water–rock interaction in addition to mixing with Plio-Quaternary aquifer waters. The combination of geochemical simulations with GIS and hydrogeochemical analyses has proven to be effective in identifying and locating the different physicochemical processes in the aquifer areas, thus improving understanding of hydrogeochemistry in complex aquifers.  
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  ISSN 0883-2927 ISBN Medium  
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  Notes Approved no  
  Call Number THL @ christoph.kuells @ Daniele2013 Serial 19  
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Author Edmunds, W.M. url  doi
openurl 
  Title Bromine geochemistry of british groundwaters Type Journal Article
  Year 1996 Publication Mineralogical Magazine Abbreviated Journal  
  Volume 60 Issue 399 Pages 275-284  
  Keywords (up)  
  Abstract \textlessp\textgreater The concentrations of Br in potable groundwaters in the United Kingdom range from 60 to 340 µg 1 \textlesssup\textgreater-1\textless/sup\textgreater . The occurrence of Br is described in terms of the Br/Cl weight ratio which enables small changes in bromide concentrations to be assessed in terms of salinity. Median values of Br/Cl in groundwaters range from 2.60 to 5.15 × 10 \textlesssup\textgreater−3\textless/sup\textgreater compared with a sea water ratio of 3.47× 10 \textlesssup\textgreater−3\textless/sup\textgreater . In recent shallow groundwaters the Br/Cl ratio is rather variable in response to a range of natural and anthropogenic inputs (marine and industrial aerosols, industrial and agricultural chemicals including road salt). Some slight enrichment in Br/Cl also occurs naturally during infiltration as a result of biogeochemical processes. \textless/p\textgreater  
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  ISSN 0026-461x ISBN Medium  
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  Notes Approved no  
  Call Number THL @ christoph.kuells @ Edmunds1996 Serial 20  
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Author El Yaouti, F.; El Mandour, A.; Khattach, D.; Benavente, J.; Kaufmann, O. url  doi
openurl 
  Title Salinization processes in the unconfined aquifer of Bou-Areg (NE Morocco): A geostatistical, geochemical, and tomographic study Type Journal Article
  Year 2009 Publication Applied Geochemistry Abbreviated Journal  
  Volume 24 Issue 1 Pages 16-31  
  Keywords (up)  
  Abstract Hydrogeological and geochemical data, in conjunction with the results of an electrical imaging tomographic survey, were examined to determine the main factors and mechanisms controlling the groundwater chemistry and salinity of the unconfined aquifer of Bou-Areg, on the Mediterranean coast of NE Morocco. In addition, statistical and geochemical interpretation methods were used to identify the distribution of the salinity. Multivariate statistical analysis (cluster and principal component factors) revealed the main sources of contamination. Groups A, B, and C in the cluster analysis and Factors 1–3 (Factor 1: CE, Cl−, K+, SO42-, and Mg2+; Factor 2: Ca2+, HCO3-, and pH; Factor 3: NO3-) represent the ‘signature’ of seawater intrusion in the coastal zone, the influence of marly-gypsum outcrops in the upstream zone, and anthropogenic sources, respectively. The ionic delta, the ionic ratio, the saturation index, and Stuyfzand’s method were applied to evaluate geochemical processes. The results obtained indicate, on the one hand, the phenomenon of salinization in both the coastal and the upstream zones, and on the other, the dilution of groundwater by recharge. Cation exchange is shown to modify the concentration of ions in groundwater. Locally, with respect to salinization processes in the coastal zone, the results of electrical imaging tomography show that salinity increases both with depth and laterally inland from the coastline, due to seawater intrusion.  
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  ISSN 0883-2927 ISBN Medium  
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  Notes Approved no  
  Call Number THL @ christoph.kuells @ ElYaouti2009 Serial 21  
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Author Gat, J.R. url  doi
openurl 
  Title The relationship between surface and subsurface waters: water quality aspects in areas of low precipitation / Rapport entre les eaux de surface et les eaux souterraines: aspects des propriétés caractéristiques de l’eau dans les zones à précipitation faible Type Journal Article
  Year 1980 Publication Hydrological Sciences Bulletin Abbreviated Journal  
  Volume 25 Issue 3 Pages 257-267  
  Keywords (up)  
  Abstract In the temperate and semiarid environment the salinity of both surface and subsurface(meteoric) waters is dominated by the weathering products of soil and aquifer minerals, since even surface waters have a history of subsurface flow. In the desert environment, in contrast, surface flows are more superficial and their chemistry dominated by the aeolian salinity. This has both a marine input and

a contribution from recycled salinity from surface accumulation of evaporitic minerals. Both these sources have chloride (and to a lesser extent sulphate) as the dominant anion.
 
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  ISSN 0303-6936 ISBN Medium  
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  Notes Approved no  
  Call Number THL @ christoph.kuells @ Gat1980 Serial 22  
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