Two new studies suggest parts of Metro Vancouver could experience much greater shaking than previously thought if the area is hit by a large earthquake.
Researchers have said in the past that the B.C. coast is 'in the risk zone' for a major earthquake.
Lead author Sheri Molnar from the University of British Columbia says that's because of the Georgia Basin, which causes seismic waves that pass through it to amplify as they make their way to the surface.
The basin lies beneath the Georgia Strait, between the Lower Mainland and Vancouver Island, and is filled with silt, sediments and glacial deposits.
TOP 5: Biggest earthquakes to hit B.C. (CBC)
Molnar says seismologists have always known that basins can increase ground shaking, but this is the first time in Canada that a study on a basin has been conducted.
Molnar and her colleagues simulated magnitude 6.8 earthquakes hitting Metro Vancouver, and found that when the waves pass through the Georgia Basin, areas in the southwestern part of Metro Vancouver shook three or four times more than if the basin were not there.
Natural Resources Canada researcher John Cassidy supervised the study, and he says the findings are important for upgrading building codes, bridge codes and other infrastructure to make them more structurally sound.
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