Earthquake and tsunami question?

It depends a lot on where the focus of the earthquake happens and certain other factors. Tsunami occur because earthquakes can dislodge material that causes a displacement of water. the big one in the indian ocean happened because part of the seafloor lifted up (about 15 feet if I recall) and forced all that water above it to try and level out again. that is a lot of water and a lot of energy and the real damage occurs when the deep water displacement gets crowded into shallower water and rolls up onto land

Since there is a subduction zone where Japan is, there are likely to be reverse or thrust faults. where one of the blocks, the hanging block, goes upward and pushes the water up, and when the water comes down, it causes waves. So I assume the bigger the earthquake, the more the water will be pushed up, so there probably has to be a sizable earthquake for a big tsunami to happen. Since California has a transform fault, it is unlikely a tsunami will originate here, but waves from nearby in Japan might be an issue for cities like San Francisco. Oh yea, there might be other things that can cause tsunamis like volcanoes or landslides as well

nah, i don't think so. it's just an island in japan right? since the crustal plates there are small, the possibility of having a tsunami is kinda small too. i'm not an expert on this but that's what i think.