Monday is the eighth anniversary of the devastating March 11, 2011 Japanese earthquake and tsunami, caused by an undersea subduction zone very similar to the nearby Cascadia, where the Pacific and Juan de Fuca plates meet.
The shaking from the 9.0 magnitude earthquake — which shifted the earth on its axis, and shortened the length of a day by about a microsecond — lasted nearly six minutes.
In the year following the event, there were more than 5,000 aftershocks, the biggest being magnitude 7.9.
Honshu, Japan’s main island, moved 8 feet eastward; the island’s north coast dropped two feet.
The Pacific Plate slid 79 feet westward near the epicenter of the earthquake.
The tsunami wave reached a height of almost 128 feet at Miyako City in Iwate Prefecture, and flooded inland for 6 miles in Sendai, a city on Honshu. In all, approximately 217 square miles were flooded. A Hokusai wave drawing is shown.
An estimated 5 million tons of debris was swept out to sea in the tsunami’s aftermath.
And, one last note: The earthquake’s infrasound (low frequency rumble) was actually picked up by a satellite orbiting in space.
Is your “go bag” ready?