Could Glen be asking about the San Andreas fault? Last large break was 1857 - on the section from Cajon pass to Parkfield - quakes average 140 years.. - we're past due.

The last large break of the area of the fault from the Salton Sea to Wrightwood was 1680 - with an average on this part of the fault at 220 years - we're past due.

This is from a paper done in 1995 (linked below) - They may have come up with some other data since then.. but.. we're past due.

Canie

• Seismic Hazards in Southern California