How Big Will it Be?

My friend asked me if all long intervals (say 320 years or more) result in 9.0 earthquakes. Remember, only 8 of the past 46 CSZ intervals have been longer than 320 years.

At the bottom of this page is a list of the intervals displayed in chronological order. Those in yellow represent the intervals that preceded Segment A Full-Rips (9.0s).

(Visit the Segment page to see more about the difference between partial & full rips.)

As you can see, there have been two times during our 10,000-year history in which intervals longer than 320 years preceded partial-rip earthquakes (8.0-8.9). 

T15a (Section D): Preceded by a 447-year interval
T10c (Section C): Preceded by a 344-year interval

During our 10,000-year history, 8 intervals were longer than 320 years, so: 

  • 1/4 of the time, intervals greater than 320 years produced partial ruptures
  • 3/4th of the time, they resulted in FULL-RIPS. That’s 75% of. the. time!

Definitely something to consider… Check out our CSZ History page for other magnitude possibilities!