This diagram shows the March 11 fault motion sequence. 1. Rupture of the fault plane begins at the epicenter. 2. Rupture travels westward, down the fault plane towards Honshu. The island suffers violent shaking for 40 seconds. 3. The upward sloping east side of the fault plane begins to rupture, continuing for 30 to 35 seconds. The sediments overlying the east side expand up the fault plane in response to the force of the rupture. 4. The water above the sediments is pushed into an unstable dome that then flows out in all directions as a tsunami.