Rounding, this was an M7 shallow thrust. What we don't know is if it was a subduction thrust with the 'hammer' going down, or a compressive thrust going up.
The earthquake was on the big subduction zone, but in the sea. Had this been a compressive thrust, the the ground motions would have exceeded 1 m/s PGV. Everything falling down, if the hanging wall was on land. As it was, some some tourists got the thrill of their lives, and life goes on.
ps. the aftershocks show the size of the fault, and a spread probably due to the sea location and poor seismometer coverage.