Twenty months ago I reported in the Huffington Post on the tsunami generated by the Chile 8.8 MM earthquake. Hilo, in particular, was concerned because the 1960 Great Chilean Earthquake of MM 9.5 (the greatest in recorded history) generated a 35 foot tsunami and killed 61. Interestingly enough, I posted this article from my hotel room in Amsterdam, for CNN fed me the unfolding story, including live webcam views of both Waikiki Beach and Hilo Harbor. Many of my friends in Hawaii fled to the hills and were out of communication.
Should Hawaii have been concerned about this 7.7 MM from Canada, their largest since 1700? My first thought was that the epicenter sounded awfully close to that feared Cascadia Subduction Zone (CSZ), and, in fact, when I Google-checked, that 1700 quake was called the Cascadia Earthquake. How imminent and serious is a mega-earthquake from the CSZ? Oregon and Washington would be crippled. However, all indications are that the Queen Charlotte Fault is not connected to the CSZ.
Anyway, about this latest, I suspected the tsunami would not amount to much because the energy released by this 7.7 tremor was all of 45 times weaker than the 8.8 of 2010 and 500 times less energetic than that world record 9.5 of 1960. Scientific sense told me that that the tsunami would be no more than a foot or two.
But you never know, for Canada is closer to us than Chile, so it would have been idiocy to go for any late night swim or await the incoming surf on a board, which, of course, some did. Certainly, it was only smart to keep away from beaches and the coastline.
However, signs from early deep ocean gauges, called DART buoys, seemed to indicate that the tsunami height might be higher than what would normally be expected from a 7.7. How high? Four to six feet on the newscasts, which is significant and potentially damaging. It was almost like some Hollywood screenwriter expanding the truth for the sake of drama. The later explanation is that there are so few earthquakes from this location that the only gauges they could refer to were peripheral.
Well, it is the following morning. No one died, there was minimal damage and some excitement. BUT, COULD THIS 7.7 CANADIAN EARTHQUAKE JUST BE A TEASER FOR A 9.0 CSZ, as this fault is very similar to that of the 2004 Indian Ocean tragedy and 2011 Tohoku cataclysm? To quote:
...a 10% to 14% probability that the Cascadia Subduction Zone will produce an even or magnitude 9 or higher in the next 50 years.