Analysis for the line chart of epicenter(Lat/Lng)-1

To predict future phenomenon, time series graph is very important.

For the analysis of Great East Japan Earthquake(M9), the time series graph of the epicenter in Sanriku-oki (1919/1-2011/3) Area as below,

Even just before Great East Japan Earthquake,it seems there is no previous indication of it in these above graphs. The some increase of occurrence has been seen, but data in 1969 was far more. So, I tried to classified the data per the depth level per 10km. As I showed, 0km(treated as 1km) is the main data. In this case, 1km data showed the most remarkable results as below,

There is long silent term before M9. For easy finding, these charts are for in 1919-2025. Unfortunately, the end of this long silent term was just after about 3hours. But, in other cases, the end times are before big earth quakes. Anyway,long silent term can show the possibility of great earthquakes as far as I have checked other data.The same pattern before M9 can be found along Japan Trench in many area.

There is another long silent term in 2012-2025 also.The outer-rise earthquake against M9 has not been confirmed.