Seminar Matteo Masotta

Abstract

The analysis of minerals in volcanic rocks is a key passage for deciphering the physico-chemical conditions at which magmas form, evolve, mix and erupt. From this perspective, basaltic magmas are probably the most interesting, as their crystallisation kinetics can result into a variety of mineral textures and compositions. At the same time, basaltic volcanism is characterised by a broad range of eruptive styles and typically short (hours to days) timescales of pre-eruptive processes. The experimental investigation of crystal nucleation, growth, dissolution and reaction with the silicate liquid, allows to put physico-chemical constraints for the parametrisation of magmatic processes, thereby enabling to read the information contained in minerals of volcanic rocks.

Mt. Etna and Stromboli are famous examples of high-risk basaltic volcanoes, being persistently active and periodically experiencing changes of eruptive style (from strombolian explosions to lava fountaining) and abrupt shifts in explosion energy (paroxysmal eruptions). Given their characteristics, these volcanoes represent natural laboratories to test empirical models derived from laboratory experiments performed at high pressure and high temperature, and simulating the conditions at which basaltic magmas crystallise, ascend and erupt. The seminar will summarise the results obtained in nearly a decade of experiments performed using natural and synthetic basaltic melts and their application to reconstruct magma dynamics at Mt. Etna and Stromboli volcanoes.