It's been 40 years since a tsunami hit Canada's pacific coast when an earthquake in Alaska unleashed waves on B.C. and killed 100 people down the coast to California. However, scientists say another tsunami may not be that far off.

"We would definitely see a tsunami if we had a large earthquake, a great earthquake along this fault line," said geologist Dr. John Clague from the Centre for National Hazard Research.

An earthquake off Canada's coast, he said, could produce a tsunami similar to the one which began beneath the ocean floor off the tip of Sumatra in Indonesia, and devastated several nearby Asian countries.

"This would require a very large earthquake but we have had these earthquakes in the recent past, the pre-historic past," Clague said.

A similar quake measuring 9.0 rocked the Pacific Ocean off the coast of B.C. in 1700 creating tsunamis that covered coastal regions with water.

Earthquakes, Clague explained, are triggered when two crustal plates collide with one another along fault lines.

A tsunami then occurs when an earthquake causes the ocean floor to rise or sink, displacing water and creating a series of large waves.

"In our case and in the case of Indonesia, two plates are coming into contact along a very long fault, in both cases, a fault that's about a thousand-kilometres long," he said.

Canada's fault line lies 100 km off Vancouver Island and extends down to northern California.

"Energy is stored up along that fault as a result of these two plates coming together both off our coast and in Indonesia," Clague told Canada AM.

"Eventually the rocks and the fault cannot hold that accumulated energy and all the energy is released in a very short period of time in one of these tremendous magnitude eight or larger earthquakes," he said.

Unlike the countries that were affected by the Indian Ocean quake, major Pacific Rim nations receive alerts from an international tsunami warning system, which was created in 1965.

Member states include all the major Pacific Rim nations in North America, Asia and South America, as well as the Pacific islands, Australia and New Zealand.

While the warning system would allow some advance notice of an approaching tsunami, Clague said it will only be a matter of minutes until tidal waves pound the shore.

"If we had an earthquake right off our coast on our own zone, the lead time would be very short. It would only be about 15 to 20 minutes."