Surface deformation resulting from subduction and slab detachment

Abstract

Convergence of lithospheric plates is accommodated at active margins by one plate moving beneath the other into the Earth's mantle. Changes in this subduction process may cause variations in the topography of the Earth's surface near a convergent plate margin. The focus of this thesis lies on surface displacements which occur during ongoing subduction and in the final stages of a subduction process. During continuing subduction, surface displacements may, for example, be due to changes in buoyancy or plate velocity. In the last phase of a subduction process, surface uplift may result from detachment of subducted lithosphere from the lithosphere at the surface. This study was motivated by indications of slab detachment in regional tomographic images of the Mediterranean region. In general, study of the dynamics of subduction may add to understanding the origin of processes at the Earth's surface, for example, the formation of mountains and basins. Vice versa, analysis of surface data may contribute to insight in the physics of subduction.