The magnitude 7.5 quake did generate a small tsunami, but the Alaska Tsunami Warning Center said the waves didn’t pose a threat.
The U.S. Geological Survey said the quake struck at about 1 a.m. Pacific Time about 100 kilometres west of Craig, Alaska and about 10 kilometres deep.
A tsunami warning quickly followed for about 1,125 kilometres of coastline from Cape Fairweather, Alaska, to the northern tip of Vancouver Island, and an advisory was issued for the B.C. coast as far south as Victoria.
A warning means an area is likely to be hit by a wave, while an advisory means there may be strong currents without widespread inundation.
Seismologist Jana Pursley of the U.S. Geological Survey said the quake was followed by six aftershocks, the strongest of which registered a 5.1 and came nearly four hours after the initial quake.
The Alaska Tsunami Warning Center had initially warned that “significant widespread inundation” of land was expected along with possible coastal flooding.
But it later cancelled the warning, saying the waves were too small to pose a threat, reaching just 15 centimetres above normal sea level.
The Alaska Earthquake Information Center said the quake was widely felt but it received no reports of any damage.
Many people took to Twitter to express their surprise as they got news of the tsunami warning.
"Seriously? Just arrived in BC; heading to Victoria tomorrow and there's a tsunami warning?" Ayelet Tsabari of Toronto tweeted.
"Wake up, check iPhone ... Slept through #Tsunami warning..." tweeted Keith Benjamin of Bella Bella, B.C.
Alex Godin, who was working at a Tim Hortons in Prince Rupert, B.C. when the quake struck, said the tremor was barely noticeable and “felt like a bump.”
This earthquake was centred not far from the Haida Gwaii region of B.C., where a magnitude 7.7 quake struck last October but caused no damage.<
A brief tsunami alert had been issued, but no giant waves materialized.
— with files from The Associated Press
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