Large scale characteristic distance between strong earthquake

The global seismicity shows a characteristic distance of about 23°. The middle-deep and deep earthquakes in the European and Asian blocks concentrate on several zones which separate about 23° away from earch other. The shallow strong earthquakes (M ^sub s^7) form belts of over 20°, the ends of these belts are near the concentration points of middle-deep and deep earthuakes. The Circular Pacific island arcs, volcanoes, shallow earthquakes, middle deep and deep earthquakes also show the characteristic distance of about 23°.[PUBLICATION ABSTRACT]