Earthquakes are usually associated with areas of the Earth where continental plates meet, such as British Columbia, but Eastern Canada, which is in what should be a tectonically stable region, has more earthquakes than models predict, and the reason for this is still uncertain. Five of the region’s seven major (greater than 6.0 on the Richter Scale) earthquakes since 1663 have been near Charlevoix, Quebec; this is thought to be due to weakening of the earth’s crust due to a meteor impact 342 million years ago.
Video: Monthly earthquakes in Eastern Canada of magnitude 2 or greater, 1975 to 2003.
Dangerous Quake Almost Every 3 Years On Avg
Eastern Canada typically experiences 400-600 seismic events per year, of which about 30 are greater than magnitude 3 on the Richter scale, and thus can be felt. About three times a decade, earthquakes of magnitude 5 or more, powerful enough to cause injury and property damage, occur in the region. Although Eastern Canada has fewer earthquakes than areas near fault lines, they travel further, because it is fault lines that contain seismic events to a localized area.
7.1 Magnitude In Eastern Canada Plausible Within Next Few Years
A Study released in October 2013, commissioned by the Insurance Bureau of Canada, suggests that a 7.1-magnitude earthquake occurring anywhere between Quebec City and Ottawa in the next few years is “a plausible scenario”, and would entail property losses of $61 billion and “significant” loss of life, as people and buildings in this region are particularly unprepared for quakes of this magnitude. The Bureau noted that insurance claims from such an event would be difficult for the Canadian insurance industry to meet.
The above animation shows all earthquakes of greater than magnitude 2, i.e. those that can be felt at their epicenter without instruments, since 1975. These earthquakes cluster in a line from Ottawa through the Saint Lawrence Valley, as well as central New Brunswick. After the year 2000, better technology allowed for more minor earthquakes to be detected even if the seismographs were far removed from the epicentre.
Eastern Canadian earthquakes of the past decade felt in major cities:
|Mar. 6, 2005||5.4||Notre-Dame-du-Portage, QC (100 km from Quebec City)|
|Feb. 25, 2006||4.5||Thurso, ON (20 km from Ottawa)|
|June 23, 2010||5||Â Val-des-Bois, QC (50 km from Ottawa, also felt in Montreal and Toronto)|
|Mar. 16, 2011||4.3||Hawkesbury, QC (30 km from Montreal)|
|Sept. 18, 2011||4.1||Thurso, ON (20 km from Ottawa)|
|Oct. 10, 2012||4.5||Verchres, QC (20 km from Montreal)|
|May 17, 2013||5.2||Shawville, ON (50 km from Ottawa, also felt in Toronto)|
- Earthquake zones in Eastern Canada (Natural Resources Canada)
- Why East Coast Earthquakes Travel Far (Scientific American)
- Microseismicity in the mid-St. Lawrence Valley Charlevoix zone, QuÃ©bec (Bulletin of the Seismological Society of America)