What is a megathrust earthquake? Subduction zone megathrust earthquakes, the most powerful earthquakes in the world, can produce tsunamis through a variety of structures that are missed by simple models. These include fault boundary rupture, deformation of overlying plate, splay faults and landslides. In this animation, we explore the three different tsunami-producing mechanisms by examining three famous earthquakes: Japan 2011, Chile 2010, and Alaska 2014. From a hazards viewpoint, it is critic