Sorry for not posting earlier or often. I have noticed a pattern, but I am not sure it really is a pattern or if it’s something I am projecting onto the data so more data required.
In the Japan area where the 9.0 happened last year, if you remove all of the after shocks but not the fore-shocks you see something interesting. Before each large quake there is a fore-shock. Or there seems to be. I may be removing more quakes as aftershocks than I should be. But here goes. 2 days before the 9.0 in march of last year there was a fore-shock, a 7.2. And this last week they had a ,6.9 in the same fault, north of the position of the 9. And it too was preceded by a fore-shock.
The fore-shocks are interesting in that they don’t produce aftershocks .That is right a large earthquake that normally would produce aftershocks but didn’t. I saw the quake right around 6 that should have produced at least 3 or 4 5+ aftershocks, but no aftershocks until the 6.9 hit which immediately produced aftershocks.
But 2 quakes do not mean there is actually something there but it warrants deeper study and I will be doing that in the next days. What I think could be happening is, since this new set of quakes is slightly north of the area the 9 was in it may have had the stress from the ground deformation caused by the 9 passed north to it and not south to Tokyo. This added stress finally pushed the fault to move but then it caught and you have a fault that wants to go and had a lot of stress on it still so the fault locks, no aftershocks but the stress is building and it lets go again but this time not re-catching and you get the larger quake with aftershocks.
Anyway we will see what the data tells us, after I get my definition of aftershock nailed down tight.