It was January 26, 1700 when a 9.0 magnitude quake struck along the Cascadia subduction zone between California and Vancouver Island causing massive destruction
On Sunday a magnitude 7.1 earthquake rocked Alaska, knocking items off shelves and walls — four homes were destroyed by explosions or fire following the quake, which occurred along the Alaskan subduction zone.
Because the earthquake was deep, there was no tsunami — one expert says it will be a much different story when the next megathrust earthquake strikes along the Cascadia subduction zone.
The last megathrust quake here was a 9.0 magnitude exactly 316 years ago— the quake generated a tsunami that spread across the Pacific, causing massive damage.
“Oral records from First Nations suggest that communities living close to the shoreline were quite decimated from this event,” said Dr. Trevor Allen, a seismologist with Natural Resources Canada.
Allen says earthquakes that large happen every 500 years or so, so there’s a roughly 10% chance one will strike in the next 50 years.
When it does he says it will be similar to the 8.8 magnitude that struck Chile in 2010.
The violent shaking there lasted about three minutes, Allen says here it would be closer to five minutes.
And like Chile, it’s falling debris that will be the most dangerous.
As for the ensuing tsunami, the west coast would be most at risk.
“We estimate they probably have in the order of 15 to 20 minutes time from when the earthquake occurs to evacuate to higher land,” said Allen.
Emergency planners say it’s important to be prepared for the first few days after the earthquake strikes.
“So you may see a bit of a gap in services being provided, that’s why we recommend a 72 hour kit so people have their initial few days of needs met,” said Kulpreet Munde, Deputy Emergency Coordinator for the City of Victoria.
And Munde says get that kit ready now because there is no knowing if the next megathrust quake will hit in 200 years or tomorrow.