Hi Canie. I will have to dig through what I have here. I do think that the article might lure some into a false sense of security because I specifically remember reading that there was evidence from the last 13 such events.

"The timing of the earthquakes is again difficult to determine accurately, but an important
marker is present near the base of some of the cores that gives the average interval between events. This layer contains volcanic ash from the eruption of Mt. Mazama in Oregon (now known as Crater Lake) dated at 7700 years ago, a huge explosion of the type of the recent Mt. St. Helens eruption. The inferred chronology for great earthquakes, assuming a constant rate of mud deposition, is similar to that obtained from the coastal marshes.The most recent turbidite event in the cores was about 300 years ago. The intervals for the last 13 events range from 300 to 900 years with an average of 590 years."

• History of Giant Megathrust events