Controls on slab detachment and subsequent topography evolution

Slab detachment causes a reorganization of the forces acting on orogenic systems and can have a distinctive signature in the geological record that may be identified through the structural,  metamorphic and topographic evolution of the orogen. However, this signature is hidden within other signals relating to the general complexity of the mountain building processes. In addition, slab detachment (or slab tearing in 3D) is a complex process that occurs on different timescales as a function of the inherent rheological properties of the lithosphere and the weakening mechanism occurring within the slab (viscous, plastic or thermal weakening).

How these properties affect the slab detachment process and to which extent these controls are reflected in the topograhic evolution of the orogenetic system is not yet fully understood. As slab detachment may occur at different depths and rates, it has different effects on the overall pull force acting on the orogen and on its post-detachment response.

Here, we employ 2D numerical experiments to systematically explore first order controls on slab detachment (slab rheology, geometry and weakening mechanisms) and the corresponding topographic evolution. Apart from the effect of lithosphere rheology and weakening mechanisms, we put particular focus on the effects of plate coupling and breakoff depth.