The 5.8-magnitude earthquake recorded Thursday morning 170 kilometres west of Vancouver Island is a good reminder — especially during Tsunami Awareness Week — that we live in an earthquake zone, says a seismologist.
The “fairly large” earthquake, detected at 8:54 a.m., was recorded on seismometers all across North America, said Natural Resources Canada seismologist John Cassidy.
The quake was too far offshore to be really felt, although a few people may have felt very weak shaking, said Cassidy.
“It was sort of at that threshold where if it had been a little bit larger, it would have been felt on northern Vancouver Island. But it’s not the type of fault that generates tsunamis typically. So there were no impacts from this event. There was no damage, no tsunami.”
Earthquakes occur off our coast and small ones are happening every day, said Cassidy, who notes the region west of Vancouver Island is one of the most seismically active in Canada.
An even larger earthquake — magnitude 6.6 — occurred in 2004. In 2014, a magnitude-6.5 quake struck the area.
“We have tectonic plates that are moving, which is what caused today’s earthquake, and they are moving all the time — about the same speed as your fingernails grow. You can’t see it, but over 50 years, over 100 years, significant amounts of movement take place.”
Earthquakes cause damage in southwestern B.C. every decade or so. Really large earthquakes occur offshore centuries apart, he said.
“Even earthquakes like the one today, if it had occurred beneath a city, that would be a pretty big one,” said Cassidy.
A magnitude-6 or 6.2 earthquake directly beneath the city is a potentially devastating event, “so it’s important to be aware and be prepared,” he said.
Thursday’s earthquake is a reminder that earthquakes have happened in the past and will happen in the future, he said.
People can take simple precautions to minimize the impacts of significant earthquakes, such as not having a a heavy picture frame over a bed or big cabinets that might fall over and block the exit from a room, said Cassidy.
It’s also important to have an earthquake kit, a flashlight and a charger for your cellphone to keep communicating in an emergency.