Foto del docente

Michele Dragoni


Department of Physics and Astronomy

Academic discipline: GEO/10 Solid Earth Geophysics

Director of Second Cycle Degree of Physics of the Earth System


Keywords: seismology fault mechanics physics of volcanism lava flows rheology geomagnetism

The research activity of Michele Dragoni is in the field of geophysics and in particular in seismology and physics of volcanism. Such an activity is devoted to the development of mathematical models of processes occurring inside the Earth and controlling the seismic and volcanic activity of our planet. The models are mainly based on the application of the theory of elasticity, fluid mechanics, rheology, thermodynamics and the theory of dynamical systems. The main topics are fault mechanics, the rheological behaviour of rocks, the strains and stresses in the lithosphere and their role in tectonic processes, earthquake occurrence, the evolution of magma chambers, the dynamics of lava flows. The results of such researches have applications in the evaluation of seismic and volcanic hazards.

In the field of seismology, Michele Dragoni has been mainly interested in fault mechanics and in the state of stress in the Earth's lithosphere. The main research topics have been: - the dislocations in elastic, viscoelastic or poroelastic media as models of the seismic sources; - the mechanisms of stress concentration in the lithosphere; - the slow propagation of dislocations and the emission of very long period seismic waves (slow eathquakes); - the recurrence properties of earthquakes on faults in homogeneous or layered elastic media; - the global post-seismic deformation and its effects on the Chandler wobble; - fault slip in the presence of friction heterogeneities (barriers and asperities); - the effects of the viscoelastic asthenosphere on the seismicity along microplate boundaries; - the rheological behaviour of plate boundaries and its effects on seismicity; - the post-seismic evolution of strain and stress in the lithosphere; - the asperity models of fault surfaces, with applications to recent earthquakes; - the aseismic slip of faults; - the depth of the brittle-ductile transition in the lithosphere; - the frictional heat production on faults and its effects on the rheological properties of rocks; - the interaction between seismic and aseismic slip of faults as a model for seismic sequences; - the deformation produced by dislocations with nonuniform slip; - the coseismic stress transfers and fault interaction; - the role of fluid diffusion in controlling the stress transfers in the Earth's crust.

In the field of the physics of volcanism, M. Dragoni has been mainly interested in magma chambers and lava flows. The main research topics have been: - the strains and stresses induced by pressurization of magma chambers; - the thermal evolution of magma chambers; - the deformation produced by solidification of magma chambers; - fracturing induced by the pressurization of magma chambers; - the formation of dikes and magma ascent through the Earth's crust; - the relationships between the rheological properties and the dynamics of lava flows; - the cooling of lava flows and its effects on lava flow dynamics; - the mechanisms of formation of lava tubes; - the dynamics of lava flows in open channels and in tubes; - the shape of the front of lava flows; - the thermoelastic deformation associated with lava tubes.

In the field of geomagnetism, M. Dragoni has been mainly interested in crustal magnetism. The main research topics have been: - the calculation of the piezomagnetic coefficients of crustal rocks; - the magnetic anisotropy produced by lava flows; - the piezomagnetic effects associated with seismic dislocations in the Earth's crust.