A Magnitude 8.0 Major Earthquake hit an island chain in the south Pacific at 5:12pm Portland time on Tuesday February 5, 2013.
Weird, second quake in the last week that’s disrupted my weather forecast during the 5pm news!
Even stranger, the idea that I’ve talked more about quakes bigger than 8.0 — some bigger than 9.0 — in the last few years than I ever have in my career. The fact is, large earthquakes ‘cluster in time’. In other words, a bunch of them hit in a ‘short’ time as far as history goes, then it seems the world’s largest quakes become surprisingly dormant.
It’s amazing to me — and spooky — that according to the USGS, 35% of the world’s largest recorded earthquakes have happened in the last 13 years. That’s right: 35% of them since the year 2000. And geologists have been recording earthquakes for about 100 years now. So, yes, that’s what I would consider ‘clustering in time’ when it comes to the world’s most powerful earthquakes.
And here in the Northwest, we are in the window of time where it seems plausible that the big one could happen anyday. The last major subduction zone mega-quake off the Oregon and Washington Coasts was back in 1700. And researchers believe the southern portion (off the southern Oregon coast and northern California) goes off every 200 years or so. So that part may be overdue.
And every 300-500 years it appears the full length of the Cascadia Subduction Zone ruptures. We’re currently at 313 years and counting. Experts believe this one could create a quake up to about 9.1 magnitude. I’ve written about the Cascadia Subduction Zone before–and done interviews on this and other faults many times.
And on the same day that the 8.0 hit the South Pacific, a new study predicts widespread loss of life and destruction here in the northwest after our next mega quake off the coast.