Lucas,Y., Schmitt,A.D., Chabaux,F., Clement（最初のeの頭に´）,A., Fritz,B., Elsass,Ph. and Durand,S.(2010): Geochemical tracing and hydrogeochemical modelling of water-rock interactions during salinization of alluvial groundwater (Upper Rhine Valley, France). Applied Geochemistry, 25, 1644-1663.

『沖積世地下水（フランスのアッパーラインバレー）の塩水化の間の水−岩石相互作用の地球化学的追跡と水文地球化学的モデル化』

『Abstract
　In the southern Upper Rhine Valley, groundwater has undergone intensive saline pollution caused by the infiltration of mining brines, a consequence of potash extraction carried out during the 20th century. Major and trace elements along with Sr and U isotopic ratios show that groundwater geochemical characteristics along the saline plumes cannot reflect conservative mixing between saline waters resulting from the dissolution of waste heaps and one or more unpolluted end-members. The results imply the occurrence of interactions between host rocks and polluted waters, and they suggest that cationic exchange mechanisms are the primary controlling process. A coupled hydrogeochemical model has been developed with the numerical code KIRMAT, which demonstrates that cationic exchange between alkalis from polluted waters and alkaline-earth elements from montmorillonite present in the host rock of the aquifer is the primary process controlling the geochemical evolution of the groundwater. The model requires only a small amount of montmorillonite (between 0.75％ and 2.25％), which is in agreement with the observed mineralogical composition of the aquifer. The model also proves that a small contribution of calcite precipitation/dissolution takes places whereas other secondary mineral precipitation or host rock mineral dissolution do not play a significant role in the geochemical signature of the studied groundwater samples. Application of the model demonstrates that it is necessary to consider the pollution history to explain the important Cl, Na and Ca concentration modifications in groundwater samples taken over 2 km downstream of waste heaps. Additionally, the model shows that the rapidly of the cationic exchange reactions insures a reversibility of the cation fixation on clays in the aquifer.』

1. Introduction
2. Study area
　2.1. Geological and hydrogeological setting
3. Materials and methods
　3.1. Sample location
　3.2. Analytical techniques
　3.3. Hydrogeochemical modelling
　　3.3.1. Hydrodynamical parameters
　　3.3.2. Geochemical parameters
4. Geochemical data
　4.1. Major element concentrations
　4.2. Trace element concentrations and U-Sr isotope ratios
　4.3. Chemical variations with time
5. Discussion
　5.1. Origin of water masses
　5.2. Water-rock interaction mechanisms
　　5.2.1. Geochemical evidence
　　5.2.2. Thermo-kinetic modelling
　5.3. Modelling the evolution of pollution fluxes and its consequences
6. Conclusions
Acknowledgements
Appendix A
References

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