A mild earthquake rumbled under Vancouver Island on Wednesday night.

The U.S. Geological Survey says the 4.7 magnitude quake occurred at 10:37 p.m. Pacific Time, about 145 kilometres west of Ucluelet, B.C.

It came one day after a 4.2 magnitude quake hit in the same region, although neither was strong enough to cause damage or injuries.

Several earthquakes have rattled the northwestern coast of North America since Monday, including a magnitude 6.0 shaker that occurred in the Pacific Ocean, about 300 kilometres west of the coast of Oregon on Tuesday morning.

The remote quake passed almost unnoticed, as did a very deep, very small, 2.5 magnitude temblor off the coast of Oregon on Wednesday and a couple of modest quakes in Northern California on Monday and Tuesday.

British Columbia occupies one of the most earthquake-prone areas of Canada, with the San Juan fault, just west of Vancouver Island, marking where a section of the Pacific plate of the earth's crust is sliding underneath the North American plate.