Aftershock distribution of the February 27, 2010 Okinawa-honto Kinkai earthquake (Japan) using sP depth phase

► The aftershocks of the 2010 Ryukyu earthquake trend toward the ENE-WSW direction. ► Double seismic structure exists in the Philippine Sea plate of the central Ryukyu. ► The earthquakes with compression stress occur in the crust of the subducted plate. ► The aftershocks with extension stress occur in the mantle of the subducted plate.