The tectonic plates at the surface of the Earth are not static but in motion and it is this motion that is responsible, for instance, for most of the energy radiated by earthquakes. I am a geodynamicist and geophysicist who studies this motion of plates and their reorganizations. To do this, I am interested in the structure and the tectonic evolution of oceanic transform faults. I collect and analyse marine geophysical data in order to better understand the structure and the dynamics of these objects. The second half of my research focuses on a more global approach using numerical modelling, including three-dimensional mantle convection models as well as the development of new quantitative methods for their analysis. The originality of my research lies in linking several scales of time and space to study plate motion, and in adopting a multidisciplinary approach at the crossroads of geodynamics, kinematics, applied mathematics and computer sciences.