It struck at 8:10 p.m. PDT and the epicentre was located about 91 km south off the coast, at a depth of about 11 km. It was originally recorded as a 6.7 but has been downgraded to a 6.6 magnitude earthquake.
Residents in Port Hardy said the ground shook for about 35 to 40 seconds during the preliminary earthquake. Groceries were knocked off the shelves at the local Overwaitea store.
People are saying they felt it as far away as Langley and Kelowna.
Earthquakes Canada is reporting the earthquake was a 5.9 magnitude.
The National Weather Service says there is no risk of a tsunami.
However, the USGS says to expect aftershocks. Two aftershocks, magnitude 5.0 and 4.2 struck the same region at about 8:20 and 8:41 p.m. PDT. These secondary shockwaves are usually less violent than the main quake but can be strong enough to do additional damage to weakened structures and can occur in the first hours, days, weeks, or even months after the earthquake.
Mayor of Port Hardy, Bev Parnham, said she was actually at a reception when the earthquake struck.
We were just in the process of welcoming the lieutenant-governor to the community, and the earth started to shake and the building started to shake, she said. It was up there with one of those ones that you do feel and that you do remember.
However, everyone remained very cool. I think by the time we realized what had happened we were all just sort of looking at each other and [said] Oh, that was an earthquake, said Parnham.
Were not hearing of any reports [of damage]. Our own infrastructure has been checked and things are fine. We havent heard any reports from any communities in the North Island. So, were not expecting to hear that there is any great deal of damage, she added.
Emergency services in Port Hardy are on alert, but Parnham said they are always prepared as they live in a seismic area.
Simon Fraser University Geologist Brent Ward said this was quite a large earthquake. Very lucky that its off the coast and its not that close to high population centres, he said. Because this is actually bigger than one of the earthquakes that hit Christchurch in New Zealand and that caused extensive damage.
This was quite shallow.
Ward said he is not surprised many people across the Lower Mainland could feel the shaking. In certain situations where people are living or on top of thick, soft, sediments, the earthquake waves actually become stronger so I would expect that people in Richmond, Delta, parts of Langely, where theyre on the thick, Fraser River sediments, would feel the earthquake, whereas someone like me, whose on sort of a bedrock area with thin sediments, I didnt feel anything.
Global BC anchor Sophie Lui felt it in downtown Vancouver. I was sitting on my couch and I heard my vertical blinds shaking, she said. And thought at first that maybe the rain had started, but they kept shaking and I looked back and my chandelier or light fixture was shaking as well. And then I realized that the shaking kept going and kept going and I thought ok I think were going through this again.
She said she did not feel the building shaking too much, but it did last about 20 to 30 seconds.
Most people around Vancouver who felt it seemed to be up high in high rises, she said.