Apollaro,C., Accornero,M., Marini,L., Barca,D. and De Rosa,R.(2009): The impact of dolomite and plagioclase weathering on the chemistry of shallow groundwaters circulating in a granodiorite-dominated catchment of the Sila Massif (Calabria, Southern Italy). Applied Geochemistry, 24, 957-979.

『（南部イタリアのカラブリアの）シラ山脈の花崗閃緑岩が優勢な集水域を循環する浅い地下水の化学的性質に与えるドロマイトと斜長石の風化の影響』

『Abstract
　This work is aimed at investigating the weathering processes of the granodiorites cropping out in a small catchment of the Sila Massif. The mineral constituents in this granodiorite are plagioclase, often zoned with a Ca-rich core and a Na-rich rim, quartz, chlorite, K-feldspar, white mica and epidote. During this study, dolomite was discovered in local stream sediments, as separate monomineralic grains, probably resulting from erosion of veins cutting the crystalline rocks. Prevailing dissolution of foreign dolomite and a Ca-rich plagioclase is suggested by the Ca-Mg-HCO3 chemical composition of local groundwaters and stream waters, which is rather unexpected for waters interacting with granitoid rocks. These qualitative observations are quantitatively confirmed by reaction path modelling of the weathering processes occurring in the study area, which was carried out using the EQ3/6 software package, version 8.0, and the Double Solid Reactant Method. Indeed, it was possible to ascertain that the release of both major dissolved constituents and several trace elements (Ba, Co, Cr, Fe, Mn, Ni, Pb, Sr, V and Zn), from rocks to waters, is chiefly controlled by the dissolution of foreign dolomite and the Ca-rich core of zoned plagioclases.』

1. Introduction
2. Geological and pedological background
3. Methodology
　3.1. Waters: sampling and analytical methods
　3.2. Rocks and stream sediments: sampling and analytical methods
4. Results
　4.1. Rock and mineral chemistry
　4.2. Water chemistry
5. Reaction path modelling
　5.1. Refurbishing the thermodynamic database
　5.2. The solid reactants
　5.3. The initial aqueous solution
　5.4. The T-fCO2-redox conditions
6. Results of reaction path modelling
　6.1. The choice of alkalinity as proxy for the reaction progress variable
　6.2. The solid reactants
　6.3. The solid products
　6.4. The aqueous solution
　　6.4.1. Magnesium
　　6.4.2. Calcium
　　6.4.3. Silica
　　6.4.4. Strontium, barium and lead
7. Considerations on the stoichiometry of plagioclase dissolution
8. Conclusions and implications
Acknowledgements
References

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