Figure 9: P-wave velocity structure of a typical intra-oceanic arc, measured by detailed OBS studies across the IBM arc at 32° 15' N. Contours represent lines of constant velocity (C.I. = 0.1 km/s; drawn thicker at 0.5 km/s intervals). Velocity structure is color-coded (after Suyehiro et al., 1996). See Figure 14 for approximate location.