Contact Information

Division of Biogeoscience
Division of Geology and Geochemistry
Division of Urban Geograpahy and Regional Studies
Study Office

P.O. Box 64
(Gustaf Hällströmin katu 2a)
FI-00014 University of Helsinki

Department Office
Institute of Seismology

P.O. Box 68
(Gustaf Hällströmin katu 2b)
FI-00014 University of Helsinki

phone +358 294 1911 (university exchange)
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GEM-Selektor is a multi-purpose geochemical modeling computer code based on the Gibbs free energy minimization method. The code is particularly suited for hydrothermal and petrological applications, because it features an unmatched choice of equation of state and activity models for minerals, aqueous and non-aqueous fluids, gases and melts.

The code has been developed since 2000 by the PSI-LES (Paul-Scherrer-Institut, Laboratory for Waste Management) team and since 2008 it is jointly developed by both the PSI (D. Kulik) and the ETH (T. Wagner) teams. This builds on earlier collaboration that evolved since 2004.

The focus of our current work is the improvement and extension of existing activity and equation of state models and related data bases, with emphasis on modeling high-temperature fluid-rock interaction and ore deposit formation processes. We use an unique approach that allows to model very complex systems involving the full aqueous speciation and many non-ideal mineral solid-solution phases over wide ranges of temperature and pressure.

It is foreseen that core parts of the thermodynamic data bases that we develop and some application examples will eventually become available for download on this website. Stay tuned ...


Simulation results of progressive fluid-granite interaction at 400 °C and 100 MPa (Dolejs and Wagner, 2008)