Ok-I'll try, but I'm not sure where you are going with this:
LA 6.8: Nothing to do with volcanos
SF 7.2: Nothing to do with volcanos
Seattle 7.1-could be an earthquake within the subducting slab, or could be a devastating shallow earthquake on one of the surface faults. Only indirectly has anything to do with volcanos-the Pacific northwest is a subduction zone plate boundary, which is why volcanos like Mt St Helens and Mt Ranier are there. But, the volcanic zome is east of Seattle.

Hawaii 6.6 Since the island of Hawaii has active volcanos, you might expect me to say this would be a volcanic earthquake. But, an earthquake this large (and they do have earthquakes this large) is most likely to be related to a gravitational collapse of the side of the volcano. But, such an earthquake might affect the volcanism....so, depends on the context what you might call such an earthquake.... Chris

How would you classify the quakes? All "just earthquakes" or separate Hawaii and possibly Seattle from LA & SF?