Subduction zone earthquakes may have recurrence times of 500-1000 years, so human memory is really of little use. (dotearth.blogs.nytimes.com)
The southern Hayward fault, which produced a magnitude 6.8 earthquake in 1868, is now approaching its mean recurrence time based on paleoseismic studies. (sciencedaily.com)
During this process small tremors of the same signature, so - called «repeaters,» occur at distinct recurrence times. (sciencedaily.com)