Temperature evolution during magma ascent in basaltic effusive eruptions: A numerical application to Stromboli volcano

The dynamics of magma ascent are controlled by the complex, interdependent processes of crystallisation, rheological evolution, gas exsolution, outgassing, non-ideal gas expansion and temperature evolution. Temperature changes within the conduit, in particular, play a key role on ascent dynamics, since temperature strongly controls the crystallisation process, which in turn has an impact on viscosity and thus on magma ascent rate. The cooling produced by gas expansion is opposed by the heat produced by crystallisation, and therefore the temperature profile within the conduit is quite complex. This complexity means that unravelling the dynamics controlling magma ascent requires a numerical model. Unfortunately, comprehensive, integrated models with full thermodynamic treatment of multiple phases and rheological evolution are challenging to produce, due to the numerical challenges involved. Until now, models have tended to focus on aspects of the problem, without a holistic approach in which petrological, thermodynamic, rheological and degassing processes, and their interactions, were all explicitly addressed and quantified.