Fig. 5

Relocated hypocenters in the present study plotted on the horizontal cross-sections of P and S wave velocities estimated by Kita et al. (2012). Green dots indicate the hypocenters of aftershocks within 2.5 km in the depth direction, and the white stars in i and l indicate the mainshock. The P wave velocities are shown at depths of 10, 15, 20, 25, 30, and 25 km in a–c and g–i, respectively. The S wave velocities at these depths are shown in d–f and j–l. Note that the color scales for a–f are different from those for g–l. Contours indicate P and S wave velocity values at intervals of 0.6 and 0.4 km/s, respectively. Green and green dashed ellipses indicate the location of intrusion of the high-velocity materials. Gray lines indicate the locations of thrust faults. The black area and thick black lines indicate the locations of the Hidaka metamorphic belt and the coast line, respectively. White-shaded areas indicate portions of DWS < 500