Influence of the length on the cohesive wedge stability and comparison with the cohesionless case (dashed curve). The ratio of the least upper bounds (mechanisms 2 and 1) is presented in (a) and the extent of the activated décollement in (b). The jump for the cohesionless wedge at the critical taper slope is replaced by a smooth transition of the thrust fold root from the back to the front if cohesion is accounted for.