There is also the very real possiblity that the 9.0 plus mega earthquake might trigger one of the many active volcanoes in Washington or Oregon.According to seismologists, the entire Pacific coastal area of North America is at risk, because of the instability posed by the Pacific plate subducting the North American plate all along the Pacific coast. But, as you have mentioned, the Cascadia Subduction Zone is particularly vulnerable, it seems. It is part of the remnant of the huge Farallon Plate that has apparently already subducted under the North American plate. One of the concerns is that the failure of the Cascadia fault could set off a much larger quake up and down the entire coastal area. Such may be the case in the lead up to the Lord's return in judgment.