The Geospatial Information Authority of Japan said their survey of the sea floor, between 40km to 130km off Miyagi Prefecture, moved 5.6 meters to 15 meters towards the east-southeast.

The Japanese Coast Guard says they confirmed sea floor movement with their seabed observation points. They say the sea floor moved 23 meters (75 feet) east-southeast, and it rose by 3 meters (9.8 feet).