Seismologists say aftershocks should continue for some time in the wake of three strong quakes off Vancouver Island last night.
At least three aftershocks have been recorded since the quakes hit more than 200 kilometers off the west coast.
John Cassidy with Natural Resources Canada says the quakes, measuring 6.6, 6.8 and 6.5 respectively, were side-slip quakes as two plates of the earth's crust rubbed sideways against each other.
" It's not unusual to see earthquakes of that magnitude. It is a little bit unusual to see 3 earthquakes of that size within a 35 minute time window."
Cassidy says the latest shakers were not subduction events where one plate slips under another, dropping the ocean floor and creating the potential for a huge tsunami.
" The subduction earthquakes tend to be some of the largest earthquakes in the world, and they are also the um, they are certainly rare earthquakes off of our coast. The really large subduction earthquakes occur hundreds of years apart so they're rare events, but they are also amongst the world's biggest earthquakes.
Cassidy says all three quakes were barely felt on Vancouver Island because they were so shallow and so far off shore, but he says they are a reminder that residents should be prepared for something much more serious.