Experimental and Computational Modeling in Petrology

Course objective:
The aim of the course is to provide the methodological foundations and analytical tools needed to quantitatively address processes involving crystalline materials, both natural and synthetic, starting from the basic principles of petrology. The course covers a series of topics focused on crystalline rocks, with particular emphasis on magmatic and metamorphic environments, as well as experimental petrology.

Principles of phase petrology:
I) Compositional space: Cartesian and barycentric coordinates, selection of components, units of compositional space (mass, atoms, oxygen, cations, and oxides), conservative and non-conservative units. Transformation of components and main applications: projections in AFM diagrams; calculation of the composition of solid solution minerals based on end members; reaction stoichiometry.

II) Phase diagrams and phase equilibria: Lever rule, phase rule, binary and ternary diagrams (complete miscibility, partial miscibility, complete immiscibility, solvus, eutectic, peritectic, and intermediate compounds); thermodynamics of homogeneous and heterogeneous systems, thermodynamic properties of solid solutions, Gibbs stability criterion and Gibbs free energy, G-X, T-X, P-T-X diagrams, sections, and projections.

The metamorphic process:
Thermodynamic modeling of phase equilibria, P-T-X relationships, use of thermodynamic software and databases; applications to geothermobarometry. Study of symplectites. Case studies.

The magmatic process:
This part of the course focuses on the petrology of the Earth's mantle and its derived melts. In particular, it aims to provide a comprehensive and updated overview of petrological processes occurring in the mantle during partial melting and melt ascent in mid-ocean ridge and hotspot settings. Special attention is given to how the chemical and isotopic composition of basalts produced in these geodynamic contexts can provide insights into the composition of the mantle source.

Practical sessions:

Experimental petrology: preparation of an experiment and textural and compositional characterization of experimental products;
Thermodynamic modeling: construction of phase diagrams under subsolidus and supersolidus conditions.
Fieldwork: excursions to sites of particular petrological interest are also planned.