>Giant earthquakes: not as random as thought
>Larger earthquakes recur more periodically: New insights in the megathrust earthquake cycle from lacustrine turbidite records in south-central Chile
A known repeat cycle of anomalistic/draconic/synodic/annual lunisolar periodic variations is
353372 years. Within that span, there is a single maximal gravitational forcing that the moon and sun apply to the earth.
From Keeling Whorf
[The Super Blue Blood Moon Wednesday Is Something the US Hasn't Seen Since 1866](https://www.space.com/39532-super-blue-blood-moon-occurs-wednesday.html)
[Tides, and the pull of the moon and sun](http://earthsky.org/earth/tides-and-the-pull-of-the-moon-and-sun)