There isn't enough information and data to come to any conclusions, but the possibilities are frightening to consider. Even if the two faults did not go off simultaneously, the one-two punch of two West Coast mega earthquakes would produce a double whammy on the economy of the nation as a whole.
I can also tell you that we in the Northwest are expecting help to pour in from Southern California to help with the disaster response to a Cascadia event.
If you are writing a disaster movie script, this might be a good place to start. You can pick up where the TV mini series 10.5 left off where the FEMA director is lowered into the Earth to manually set off an atomic bomb that is expected to stop more earthquakes from happening.
Sorry, Pete Gaynor, FEMA administrator — the earthquake gods demand human sacrifice!
Claire Rubin shared the link above.
