[9] The magnitude 7.3 shock generated a small tsunami, with waves up to 1 m high, that hit Ishinomaki in Miyagi Prefecture.

[10] It occurred at a depth of 36 km within the Pacific plate and was the result of reverse faulting, about 20 kilometres (12 mi) east of the Japan Trench.

The 1 metre (3.3 ft) tsunami caused a mountain of sandbags to collapse in Ishinomaki.

[7] An old man went missing and was found dead on December 14 after he sailed out to sea to try to evacuate from the tsunami in Kuji.

According to studies, the shocks moved from the outer and deeper limits into the mainshock epicenter.