Pro- vs. Retro-Foreland Basins
Collisional mountain belts are inherently asymmetric; defined by the convergence of a subducting slab towards a static over-riding slab. This drives an asymmetric topographic form and first order differences in the boundary conditions that drive evolution in the bounding foreland basins.
The basin which overlies the subducting slab is continually translated towards the mountain belt generating new accommodation space. In contrast, the retro-side basin primarily grows with an increasing topographic load and ages when the topography finds a steady state.
