Fig. 1

Location and geology of the studied area. a Regional map showing major plate boundaries, the distribution of accretionary complexes of the Japan island arc, and the locations of the two study areas of this paper. EUR Eurasia plate, NAM North America plate, PHS Philippine Sea plate. Maps showing simplified geologic structure in b the area of outcrop of the Emi Group, modified from Hirono et al. (2008b), and c OSTs around the Kure Mélange, modified from Honda et al. (2011)