[eigenform]

No reason that the rate of subduction has to be the same everywhere. Some of the plate boundaries might be moving into each other in different directions too, the coupling between plates is not necessarily the same everywhere.

Anyway, in the case of Cascadia, remember that the lack of big earthquakes over the past 100 years is probably telling you that we just happen to live in a time where strain is accumulating (D:)

[floxy]

Yes, I guess we should hope for a lot of M6 quakes in the near term. Or hope that in 100 years the infrastructure will be much more quake resilient than today.