The Global Map has been divided into 16 zones according to each area's characteristic location. The Global Map only shows Big Earthquakes (Magnitud > 8.0). Taking into account seismicity > 7.0 (major and Big Earthquakes) for the period 1973 01 01 thru 2006 12 31, zones number 9 (Sumatra 20.5%) and number 6 (Tonga 18%) are the most seismic zones in the world. Next come zones number 5 (Japan and Philipines 10.3 %) , number 1 (Nazca Plate Subduction Zone 9.5 %) and number 4 (Alaska and Kamtchaka 8.2%). Zone number 10 accounts for 5.6%, and zones number 2, number 3, number 8, number 11 and number 12 account for around 3 % of total global seismicity.
Taking into account a longer period of time, 1940 thru 2006, some positions change, but overall, the pattern of seismicity holds. Extrangely enough, this same pattern of seismicity that you see in the Global Map for Big Earthquakes in 30 or 60 years, you see for a period of 30 to 60 days if you take into account earthquakes of magnitude > 4.0 or > 5.0.
The Global Map shows four Big Earthquakes of magnitude = or > 8.4. These are Sumatra (9.0), Antartic Plate (8.8), Alaska (8.5) and Southern Peru (8.4).
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