Don,

Thanks. But, not really what I was talking about. And, I don't want to analyse data...this is just a hobby for me. What I was talking about is to look at the M8+ earthquakes that occurred on this part of the subduction zone, see when the last one was, and see if there was anything interesting before (like, M7s with shallow hypocenters out by the trench). You could go back 100 years. Or, you could use historical records and go back 1000 years. This has most likely already been done, so you can just use your Japanese and find out who has done this (OK, Japanese seismologists would read English, and the person who has done this work need not be Japanese. Only do this if it interests you....I'm not going to do anything with your results.
Chris, back in suburbia.