VICTORIA - Scientists are warning that if B.C.'s south coast is going to be hit by an earthquake soon, it's likely to happen during the next week.
A series of tremors that started in Puget Sound along the U.S. West Coast three days ago are working their way up Vancouver Island and are being tracked by seismologists at the Geological Survey of Canada.

The low-level shaking, which can be picked up only by sensitive equipment installed up the coast by U.S. and Canadian governments, rumbled through southern Vancouver Island Thursday, said seismologist Garry Rogers at the Pacific Geoscience Centre in Sidney, B.C..

The tremors are caused by a tear in the bottom plate of the Cascadia fault. Pacific Geoscience Centre scientists discovered in 2003 that the tremor activity happens regularly every 14 months, and so can be accurately forecasted.

"Vancouver Island, the edge of the continent, is usually storing up energy like a giant spring. Vancouver Island is usually moving towards Ottawa, and now it is moving towards Japan," Rogers said.

Scientists believe the direction change of the sticking and slipping will continue for about a week, after which the plates will start behaving normally again.

The question, however, is how much extra stress the episodes add to the plates, and how much closer it brings B.C. to the "big one."
The next window of high earthquake risk will be about April 2008.