3 ms·eh...the timing is from that quake in 1700, tsunami from which devastated Edo Japanby caycep 4y agoeh...the timing is from that quake in 1700, tsunami from which devastated Edo Japanmwest217 4y agoThe timing is actually based on seafloor cores, and finding 41 earthquakes in the last 10,000 years.bee_rider 4y agoMy comment was a joke (random intervals don't work that way).