text:  An eight magnitude quake in the islands? Yeah, on the big island. That's about the only place that's still shaking really strongly. Well, I know, but wouldn't something like that potentially produce a tsunami? It could. A tsunami requires up and down motion on the seafloor. So the San Andreas Fault isn't going to give you much of a tsunami. It's like if you have a big dishpan full of water and there's a big platter in the bottom.