Physical modelling of lava flows

Abstract

Lava flows are not only a fascinating scientific problem, involving many branches of continuum mechanics and thermodynamics, but are natural events having a strong social impact. A reliable evaluation of volcanic hazard connected with lava flows depends on the availability of physical models allowing us to predict the evolution of these phenomena. In this regard, the rheological properties of lavas are of major importance in controlling the dynamics of lava flows. Lava is a multi-phase and chemically heterogeneous system. This entails a characteristic, non-Newtonian behaviour of lava flows, which is emphasized by the fact that the rheological parameters are strongly temperature dependent and are therefore affected by the progressive cooling of lava after effusion. Physical models of lava flows show us the complex relationships between the many quantities governing this process and in the near future they may allow us to predict the dynamics of lava flows and to take effective measures for the reduction of volcanic risk.