  We study the birth and propagation of a delamination front in the peeling of
a soft, weakly adhesive layer. In a controlled-displacement setting, the layer
partially detaches via a subcritical instability and the motion continues until
arrested, by jamming of the two lobes. Using numerical solutions and scaling
analysis, we quantitatively describe the equilibrium shapes and obtain
constitutive sensitivities of jamming process to material and interface
properties. We conclude with a way to delay or avoid jamming altogether by
tunable interface properties.
