Hi Diane. You should expect an M=6.0 to M=7.0, but you could also get an M=7.0 to M=8.0. No one really truly knows what the magnitude of the next major quake will be. They can only give probabilities and that largely depends on where the quake occurs and when.

Damage during a quake depends a lot on the type of quake (strike-slip, thrust, or normal) and the type of construction used in building.

It could occur tomorrow or 20 years from now or even 30 years from now, or next year. At present time there is no way of knowing. This is why you prepare for the worst quake which in this case could be up to about M=7.6 using the known quake history of the area as a guide. Take Care…Don in creepy town