Fig. 4
Frequency distribution of b-values in each region. a Frequency distribution of b-values in the southern Okinawa Trough. b-values were calculated using MV. The numbers with arrow show the b-value for the entirety of the box. b The same as a but in the central Okinawa Trough. c The same as a but in the southern Ryukyu arc. d The same as a but in the central Ryukyu arc. e The area of each region is shown. The b-values are shown in color. The location of the plate boundary is from Bird (2003)