抄録
Lithospheric deformation at a subduction zone due to the collision and the consequent interaction between a trench and a seamount on the oceanic plate is examined using numerical simulation of the motion of viscous fluid. The results show that the slab-pull force at the trench cannot disappear even if a seamount collides against it. In the case of a small seamount the subduction motion continues, while in the case of a large seamount the motion of subduction terminates temporarily and another subduction takes place at the seaward edge of the seamount.