Below is a list of terms used in this project. You can learn their definition in the context of this project by clicking on them.
The map below describes three types of plate boundaries found at the western edge of North America: the San Andreas Fault, the Cascadia subduction zone and the Juan de Fuca Ridge, which carries the ocean floor of the Juan de Fuca Plate down the Cascadia subduction zone. These plate tectonic characteristics are the plate boundaries responsible for Vancouver’s high risk of an earthquake and its resulting tsunami/floods that could occur. The three different types of plate boundaries are the unique triple junctions associated with the Cascadia subduction zone.
Why is Vancouver at risk?
Vancouver’s densely populated city lies in the worst seismic hazard zone in Canada, and the potential damage to bridges during a major quake could isolate the city. The area immediately west of Vancouver is considered one of the most vulnerable in the country. In the Juan de Fuca Strait, two tectonic plates – the North American Plate and the Juan de Fuca Plate – rub against each other. The North American Plate is gradually sliding underneath its neighbor, building pressure along the plate boundary. Eventually, scientists say, this will cause a "subduction earthquake," an incredibly powerful event that could measure up to a magnitude of 9.
Based on geological evidence in the region, it's believed that such quakes strike every 300 to 500 years. Canada is a veritable hotbed of seismic activity. The country averages three to four earthquakes a day – more than 1,200 a year. The sensitive equipment that measures seismic activity can only detect the vast majority of them. But – a few times a year – Canadians do feel the earth move. The most active parts of the country are the western and southwestern regions of British Columbia, including Vancouver Island and the Queen Charlotte Islands, which are struck more than 200 times a year.
A disaster can be any large-scale natural hazard such as an earthquake or tsunami. The Vancouver area has been expecting a large seismic event to occur for a period of hundreds of years. This is referred to as the return period of an earthquake. In general there is a logarithmic linear relationship between the intensity of an earthquake and the return period. The last record of a major earthquake was approximately 400 – 500 years ago. This means that the upcoming earthquake is expected to be fairly large, considering the size of the seismic gap. Therefore the Vancouver area has high potential for experiencing damage and the need for disaster routes for the public is necessary.
The above maps and their plotted points indicate the recent earthquakes in the last 1 year (first map), and the last 30 days (second map). The legend indicates the magnitude of the earthquakes and the yellow point on both maps is the most recent earthquake recorded. These maps are updated on a daily basis on the Natural Resources Canada website – www.nrcan.gc.ca
Current disaster response planning in Vancouver
Emergency Management BC is a governmental organization. The Provincial Emergency Program (PEP) is a division of the Ministry of Public Safety and Solicitor General, Emergency Management BC. PEP works with local governments year round, providing training and support before, during and after emergencies.
Emergency Management BC offers easily accessible information online and downloadable PDF’s of various Hazard plans:
