According to Earthquakes Canada, three earthquakes struck off the coast of Vancouver Island between 2:58 a.m. and 8:18 a.m. Pacific Daylight Time (PDT) on Sunday morning. The magnitude 5.5 quake, the strongest in the series, struck at a depth of eight kilometers, about 213 kilometers west of Port Hardy.
There is no fear of a tsunami following these three earthquakes and no damage has been reported, Earthquake Canada adds.
Marine mammal ecology researcher Lyne Morissette explains that a quake of this magnitude is usually felt where the epicenter is. However, since it is located under the ocean and far from land, the likelihood that the slightest vibration was felt is slim.
“We have a beautiful system of sensors that can sense or count these types of tremors offshore,” she explains.
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The approximate location of the epicenter of the earthquake.
Photo: Earthquake Canada
The series of earthquakes in British Columbia came more than a week after the catastrophic earthquake in Morocco that killed thousands of people. Can a connection to the activities of the earth’s crust be established here as elsewhere?
At the moment it seems to be a matter of chance. Unlike other major environmental issues, it is very difficult to draw correlations. “This is the case when we talk about hurricanes that have a connection with climate change, but what is happening on the earth’s crust is so far in the realm of chance, it is not correlated,” replies the researcher.
A system for the advance detection of earthquakes
Lyne Morissette has just returned from a mission in Victoria, where a team of scientists from the University of Victoria developed technology that enables early underwater detection of earthquakes. The project was announced by the provincial government last January.
Ocean Networks Canada uses an arsenal of 105 instruments to detect tremors between 30 seconds and 4 minutes before they occur.
It may not seem like much, but it can make a big difference in the number of deaths, the number of injured and the material losses, says Lyne Morissette. This can, for example, result in trains slowing down and stopping traffic on bridges or in tunnels or interrupting landings in air traffic.
This system uses sensors located hundreds of meters underwater in the subduction zone, where tectonic plates collide, often causing earthquakes.
Why there? Because when we are in British Columbia, we are near the Pacific Ring of Fire: it is a seismic region that is very active. There are thousands of earthquakes, most of them very small, she says. There are more than 3,000 earthquakes every year in British Columbia alone.
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A tsunami warning sign in Tofino, Vancouver Island.
Photo: Radio-Canada / Geneviève Lasalle
She adds that this technology allows for better preparation for the famous “Big One”, the devastating earthquake that has been expected for several years on the west coast of the continent.
Lyne Morissette points out that the shaking on Sunday morning does not allow us to make predictions for this expected major earthquake. These are not linear models. “It is not because we have one shock today that we will have another one next week,” she emphasizes.