Fig. 11

Interpretation of the velocity structures a for two depth slices and b along two across-arc vertical cross sections. The Wakayama swarm is shown by an orange circle in the depth slices and an orange ellipse in the vertical cross section. Green areas are interpreted to be rigid and impermeable materials. See the text for further details. c Distribution of the air-corrected ³He/⁴He ratios (Sano and Wakita 1985; Matsumoto et al. 2003; Umeda et al. 2007; Sano et al. 2009; Morikawa et al. 2016). The purple ellipse denotes an area of uplift at > 4 mm/year (Yoshida et al. 2011)