These are just a thing of beauty. Look at the beautiful trenches! They can only be achieved by M9+s every few hundred years. Otherwise, they would get all goopy.
No fault plane solution on this, but it will be pure downthrust. This whole curve could go in a big M9.3, which is three times longer than that little M9 by Japan. We won't talk about that, because the tsunami would make that other one look like a dog puddle. As we know, these things are much more common than a meteor strike!