The Mj 7.3 (Mw 7.0) mainshock produced extensive and complex surface ruptures in and around the active Futagawa-Hinagu fault zone, including primary right-lateral faulting, slip-partitioned normal faulting, and distributed and triggered surface breaks, as well as minor surface ruptures associated with the foreshocks of up to Mj 6.5 (Mw 6.2).