Earthquakes in Pacific Canada
Authors:   Natural Resources Canada
Published: March 2017

Major earthquakes in Japan, New Zealand and Chile have made many Canadians wonder if the same thing could happen here. Those events remind us that earthquakes can cause major damage and possibly loss of life.

Earthquake activity, is common across much of Canada. Each year, seismologists record and locate approximately 5,000 mostly small earthquakes across the country.

Although scientists canmp;gt;'t predict when an earthquake will occur, research can help us take steps to prepare for, and reduce losses from, future earthquakes. Scientists with Natural Resources Canada study earthquakes around the world. That research helps us understand what could happen here and
learn how we can better protect our homes and communities. Earthquake research is important to modern building codes, helping us create structures to withstand earthquake hazards. This is particularly important on the coast of British Columbia. The Pacific Coast is part of the Pacific Ring of Fire.

and is the most earthquake-prone region in Canada. In fact, earthquakes occur every day on the west coast. In the offshore region to the west of Vancouver Island, more than 100 earthquakes of magnitude 5 or greater have occurred during the past 70 years. If these are near land, the shaking would be
quite unsettling with dishes falling off shelves and minor damage occurring. Every 250 to 850 years, there is evidence of giant earthquakes of approximately 9 occurring off the west coast.

These large mega thrust earthquakes can cause extensive damage to urban areas and are similar to the one that struck Japan in March 2011. In February 2010 a subduction earthquake hit the coast of Chile. Chile presents a compelling case study, and not only because its quake produced the kind of
shaking that may affect Vancouver and Victoria. It also has in place similar building standards to those in Canada. John Cassidy of Natural Resources Canada had a chance to visit the area. That earthquake was a magnitude 8.8 and it occurred when an ocean plate just offshore of Chile was pushed
beneath the continent. It moved about 20 meters, and it caused very strong shaking that people felt for two or three minutes. Here in British Columbia we have exactly the same type of tectonic setting. An ocean plate offshore is being pushed beneath Vancouver Island, Washington, and Oregon, and we
have exactly the same type of earthquakes along our coast. We also know that our building codes are very similar to those in Chile, and so shortly after the earthquake I travelled with a group of earthquake engineers to Chile and we travelled through the hardest hit regions of the country to look at
damage patterns and to learn what we can apply here in British Columbia. What we found was that the area of impact of that earthquake was huge -- 600 kilometres long, and going about 100 kilometres inland. It damaged buildings, and bridges, and highways, and seriously impacted the economy. In the
coastal areas where there was very strong shaking there was also a tsunami 2 to 3 meters high, but in some areas ten or fifteen meters high and that tsunami came in twenty or thirty minutes after the earthquake, and in some cases a few hours, after the earthquake. What we found specifically was the
oldest buildings were the hardest hit, those buildings that were constructed before modern building codes. Modern buildings in general did well, but there was still damage to the interior of those buildings, and there was a lot of damage to the outside with windows and bricks coming down. Modern
building codes in Chile, the result of a lot of earthquake research, saved thousands and thousands of lives NRCanmp;gt;'s earthquake research helps us understand seismic activity and supports efforts across Canada to minimize damage to our roads, bridges, houses and communities. No one can say for
sure when the next big earthquake will hit the Pacific coast, but by knowing what could happen, we better equip Canadians with the information they need to prepare. For more information, visit our website at EarthquakesCanada.ca and follow us on Twitter at Twitter.com slash Canadaquakes, to get the
latest information on magnitude, location, and time of earthquakes in Canada.